JP2512645B2 - Drawing machine with multi-die cushion - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressing machine for drawing a material to be drawn into an arbitrary shape. More specifically, in the drawing process, the pressure can be delicately controlled at each position of the wrinkle holding portion. The present invention relates to a draw forming press machine having an NC type multi-die cushion.

[0002]

2. Description of the Related Art Conventionally, a press machine can be used to select a material to be drawn.
When drawing in the shape of
Supply pressure oil that outputs a constant wrinkle holding pressure.
Ordinary throttle control method in which the presser foot pressure is kept constant
However, as the shape becomes more complicated in recent years, the molding process
The wrinkle holding pressure of multiple die cushion cylinders
Means to control the force are employed.

[0003]

[SUMMARY OF THE INVENTION The conventional drawing system
In the control method, the material to be drawn is drawn into an arbitrary shape.
During the molding process, the operator
The wrinkle holding pressure of the cylinder cannot be quantitatively recognized.
Therefore, depending on the feeling of the operator, each die cushion
Is it necessary to set the wrinkle holding pressure of the Linda?
, Plastic may be broken during the plastic deformation, or wrinkles may occur.
There is a problem of rinsing. Therefore, in the present invention, the operator
However, it can be used depending on the material, plate thickness, shape, etc. of the drawn product.
Select the optimum position of the die cushion cylinder to be used
It also corresponds to the moving position of the blank holder.
Hold down pressure to the above die cushion cylinders
Set for each die cushion mold during the molding process.
The operator quantitatively recognizes the actual wrinkle holding pressure of the Linda.
Be aware that the actual wrinkle presser pressure and set pressure
If there is a deviation between the
To improve the quality of drawing products.
This is a technical issue.

[0004]

[Means for Solving the Problems ] Techniques for Solving the Problems
The operative means is a block that moves up and down in conjunction with the die cushion pin.
Place the drawn material supported by the rank holder on the upper die and
When molding by squeezing with the lower mold attached to the bolster
To, said through the die cushion pin Blanc Kuhoru
Multiple die cushion cylinders that drive the daugers up and down,
Multi-selectable according to the characteristics of draw-formed products
In addition to arranging in a formula, each die cushion series
Equipped with a pressure control valve that controls the pressure of the pressure oil to the
For drawing presses with multi-die cushions
And used according to the characteristics of the draw-formed product
Die cushion to select and set die cushion cylinder
Selection input section and its die cushion selection input section.
Select the set position of the die cushion cylinder.
Die cushion array monitor to display and drawing process
Corresponding to the moving position of the blank holder in
Hold down pressure to the above die cushion cylinders
The pressure setting section set for each
The pressure of each cylinder is detected and the detected pressure is handled.
Pressure sensor for outputting a signal, and the blank holder
Position and outputs the signal corresponding to the detected position.
Blank holder-position detector and its blank holder
-By inputting the signal from the position detector,
Recognize the actual position and
The wrinkle holding set pressure by the cushion cylinder
After reading from the pressure setting unit,
And output the drive signal corresponding to the set pressure for wrinkle holding
Input the signal from the valve control means and the pressure sensor
The actual pressure of each die cushion cylinder.
It is equipped with a pressure monitor that monitors and displays.
It

[0005]

According to the present invention, before forming the material to be drawn,
The optimum die for the material, plate thickness, shape, etc.
The position of the cushion is selected and the die cushion array model is
The input part selected in the die cushion selection input part
The position of the die cushion cylinder is displayed.
For each selected die cushion cylinder.
To meet the material, plate thickness, shape, etc. of draw-formed products.
Set the presser foot pressure for each arbitrary movement position of the blank holder.
When the press machine is operated with
The die descends and at the same time the die cushion cylinder descends.
The blank holder descends, the upper mold and the blank holder
When the material to be drawn supported by and contacts the lower mold
Molding starts from. The valve control means is the blank holder
Blank holder position by inputting a signal from over the position detector
Position is recognized and the recognition position is set by the pressure setting unit.
When the position where the presser foot pressure is output,
The force is read from the pressure setting section and applied to each pressure control valve.
On the other hand, drive current corresponding to the wrinkle presser set pressure is applied. So
Each die cushion cylinder receives pressure oil from the pressure control valve.
Wrinkle presser pressure equal to the set pressure
When the pressure sensor outputs
The actual wrinkle holding pressure output by the
Output to the pressure monitor and display that pressure.
The pelletizer is used for each die cushion cylinder in the molding process.
The actual wrinkle presser pressure output by the
It

[0006]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view showing a pre-molding state of the drawing press of this embodiment, and FIG. 2 is a layout drawing of 68 die cushion cylinders. 3, FIG. 4, FIG. 5, and FIG. 6 show the die cushion cylinders used in the case of different molded products by black circles. Further, FIG. 7 shows a state of the press machine after molding and a hydraulic circuit of the press machine. As shown in FIGS. 1 and 7, a main pressurizing cylinder 2 is attached to the upper part of the press body 1, and a slide 4 is attached to the lower end of a rod 3 of the cylinder 2. Further, an upper die 5 is attached to the lower end surface of the slide 4.

On the other hand, for example, 68 die cushion cylinders 6 are attached to the lower portion of the press machine body 1.
A die cushion pin 8 is attached to the upper end surface of each rod 7, and a blank holder 9 is attached to the upper end portion of each die cushion pin 8. A lower die 12 is attached to an upper end surface of a bolster 11 supported by the frame 10 while inserting each die cushion pin 8. Insert the die cushion pin 8 into the lower mold 12,
The blank holder 9 is constructed so that the lower mold 12 can be raised and lowered.

As shown in FIG. 1, the material 13 to be drawn is supported by the upper die 5 and the blank holder 9 and waits for the start of molding. A position sensor is embedded in the rod 7 of each die cushion cylinder 6 for moving the blank holder 9 up and down, and an analog signal output type absolute coder is provided as the position detector 14 of the blank holder 9. . As shown in FIG. 7, the hydraulic source of the hydraulic circuit for supplying required pressure oil to the main pressurizing cylinder 2 and the die cushion cylinder 6 is a main pump 2 driven by a motor M.
1, the pressure oil output from the main pump 21 is used to switch the vertical direction of the main pressurizing cylinder 2 to the main pressurizing cylinder up / down switching valve 22 and the die cushion cylinder 6 to switch the vertical direction. Oil is sent to the cushion cylinder up / down switching valve 23. Further, each of the proportional electromagnetic pressure control valves 24 for controlling the wrinkle holding pressure when the die cushion cylinder 6 generates the wrinkle holding pressure is provided in the bypass circuit 26. Further, each pressure sensor 26 that detects the pressure of each die cushion cylinder 6 and outputs a signal corresponding to the detected pressure is attached.

Next, according to FIG. 8, the die cushion cylinder 6
The selection and the wrinkle presser pressure control configuration will be described. As shown in the same figure, it is assumed that it is the center of both of the above-mentioned controls, for example, a microprocessor CPU is used, and a random access memory RAM and a read-only memory ROM are connected to the microprocessor CPU, and signals from the outside are input. In addition, an input / output interface I / O having an input / output function for outputting a signal to the outside and an output interface OUT having an output function for outputting the signal to the outside are connected.

A press machine control device 31 for controlling the drive of the press machine body 1 is connected to the input / output interface I / O, and signal communication is performed with the microprocessor CPU via the input / output interface I / O. I do. The signals output from the press machine control device 31 to the microprocessor CPU include, for example, an inquiry signal as to whether or not the press machine may start operation, an abnormal signal, and the like. The signals to be output include an operation preparation completion signal. Further, the input / output interface I / O includes a signal converter 32 for exchanging a signal output from the blank holder position detector 14 into, for example, a digital signal, and each of the pressure sensors 2.
An amplifier 33 that amplifies the signal output from 6 and then converts it into a digital signal is connected. On the other hand, each proportional electromagnetic pressure control valve 24 is connected to the output interface OUT.
An amplifier 34 for connecting a drive current for driving each is connected.

The microprocessor CPU has the input / output interface I / O and the output interface OU.
T, a random access memory RAM, a read only memory ROM, and a pressure setting unit 35 for setting a wrinkle holding pressure corresponding to the moving position of the blank holder 9.
And a die cushion selection input section 36 for selecting an optimum position from a large number of arranged die cushion cylinders 6, and a pressure monitor section composed of a CRT for graphically displaying the pressure detected by each pressure sensor 26. 37 is connected to a die cushion array monitor unit 38 which is a CRT for graphically displaying the data selected by the die cushion selection input unit 36.

The wrinkle presser pressure setting method in the pressure setting section 35 and the optimal arrangement setting method of the die cushion cylinders 6 in the die cushion selection input section 36 use, for example, a keyboard provided on the operation panel of the press machine. N selected from the die cushion cylinders 6
As shown in FIG. 10, a blank holder position and a wrinkle holding pressure value corresponding to the blank holder position are stored in the random access memory RAM for each piece.

Next, the wrinkle holding pressure control operation will be described with reference to the wrinkle holding pressure control flowchart shown in FIG.
In FIG. 9, when the microprocessor CPU is powered on, an electric control circuit including the microprocessor CPU is initialized as shown in step S1.

Next, in step S2, the microprocessor CPU determines whether the optimum die cushion cylinder 6 has already been selected (1 to n) by the die cushion selection input unit 36 according to the material, plate thickness, shape, etc. of the drawn product. If it is determined that the same selection has already been completed, it is determined in step S3 whether the optimum wrinkle presser pressure has been set for the pressure setting unit 35 for 1 to n, and the same setting has already been completed. If it is determined that the step S
In step 4, it is determined whether or not the press machine body 1 is in an operable state by signal communication with the press machine control device 31. As a result of the determination in step S4, when the microprocessor CPU confirms that the press machine main body 1 side is ready for operation, the microprocessor CPU determines in step S5.
At, the operation signal is output to the press control device 31 to indicate that the wrinkle pressing pressure control can be started. When the main pressurizing cylinder 2 on the press machine body 1 side starts to descend and at the same time the die cushion cylinder 6 descends,
The drawing material 13 to be drawn comes into contact with the lower mold 12 to start drawing. The microprocessor CPU inputs the signal from the blank holder position detector 14 in step S6, recognizes the position of the blank holder 9, and
Whether or not the same position is the position where the wrinkle pressing pressure is changed is determined for each of the die cushion cylinders (1 to n), and when it is determined that the same position is the position where the wrinkle pressing pressure is changed, In step S7, the wrinkle presser pressure set value corresponding to the same position is read from the pressure setting unit 35, the same pressure value is exchanged for a drive signal corresponding to the drive amount of each proportional voltage control valve 24, and the amplifier 34 is replaced. Output to. The amplifier 34 inputs the drive signal and supplies a drive current to the corresponding proportional electromagnetic pressure control valve 24 to supply the required pressure oil to the die cushion cylinders 6 (1 to n).

In the next step S8, the microprocessor CPU inputs the signals from the respective pressure sensors 26, calculates and recognizes the actual wrinkle pressing pressure value, converts it into a pressure monitor signal, and then the pressure monitor section. It is output to 37 and the actual wrinkle pressing pressure is displayed on the monitor. In reality, since the wrinkle holding pressure set point set by the pressure setting unit 35 is multipoint in the blank holder descending range, the routine between step S6 and step S8 is executed for each wrinkle holding pressure set point. When the wrinkle presser pressure control corresponding to the final wrinkle presser pressure set point is completed for all 1 to n of the selected die cushion cylinders 6, the one cycle of the presser foot presser pressure control is completed as shown in step S9. The operation signal is turned off in step S10. Therefore, the actual wrinkle presser pressure and setting
If there is a deviation from the pressure, the operator will
Since it can recognize
As a result, product quality and yield are improved.

[0016]

As described above, according to the present invention, the aperture is reduced in advance.
Die cushion type used according to the characteristics of molded products
By selecting and setting the Linda, the selected die
The position of the cushion cylinder is the die cushion array monitor
Is displayed on the screen and the moving position of the blank holder
Wrinkle holding pressure corresponding to each die cushion
Selected die cushion to set for each cylinder
For each cylinder, the actual work in the drawing process
The work clamp pressure can be monitored with the pressure monitor.
Therefore, the operator is the selected die cushion cylinder.
Quantitatively recognize each actual wrinkle holding pressure value
The actual wrinkle presser pressure and set pressure can be
If there is a deviation between the
A product of good quality with very few wrinkles.
There is an effect that it can be drawn.

[Brief description of drawings]

FIG. 1 is a schematic front view of a draw forming press having a multi-die cushion.

FIG. 2 is a plan view showing the overall arrangement of a die cushion cylinder.

FIG. 3 is a layout view of a die cushion cylinder used for holding wrinkles.

FIG. 4 is another layout drawing of a die cushion cylinder used for holding down wrinkles.

FIG. 5 is another layout drawing of a die cushion cylinder used for wrinkle pressing.

FIG. 6 is another layout drawing of the die cushion cylinder used for wrinkle pressing.

FIG. 7 is a hydraulic circuit diagram of a drawing machine having a multi-die cushion.

FIG. 8 is a wrinkle press control block diagram.

FIG. 9 is a wrinkle press control flow chart.

FIG. 10 is a wrinkle press control characteristic diagram.

[Explanation of symbols]

 1 Pressing Machine Main Body 2 Main Pressurizing Cylinder 3 Rod 4 Slide 5 Upper Die 6 Die Cushion Cylinder 7 Rod 8 Die Cushion Pin 9 Blank Holder 11 Bolster 12 Lower Die 13 Drawing Material 14 Blank Holder Position Detector 21 Main Pump 22 Main Pressure cylinder up / down switching valve 23 Die cushion cylinder up / down switching valve 24 Proportional electromagnetic pressure control valve 26 Pressure sensor 35 Pressure setting unit 36 Die cushion selection input unit 37 Pressure monitor unit 38 Die cushion array monitor unit CPU microprocessor

Claims (1)

(57) [Claims] 1. Lifting and lowering in conjunction with a die cushion pin.
Use the upper mold to draw the material to be drawn supported by the blank holder.
And when squeezing with the lower mold attached to the bolster
The blank holder via the die cushion pin.
Multiple die cushion cylinders that drive the daugers up and down,
Multi-selectable according to the characteristics of draw-formed products
In addition to arranging in a formula, each die cushion series
Equipped with a pressure control valve that controls the pressure of the pressure oil to the
For drawing presses with multi-die cushions
And used according to the characteristics of the draw-formed product
Die cushion to select and set die cushion cylinder
Selection input section and its die cushion selection input section.
Select the set position of the die cushion cylinder.
Die cushion array monitor to display and drawing process
Corresponding to the moving position of the blank holder in
Hold down pressure to the above die cushion cylinders
The pressure setting section set for each
The pressure of each cylinder is detected and the detected pressure is handled.
Pressure sensor for outputting a signal, and the blank holder
Position and outputs the signal corresponding to the detected position.
Blank holder-position detector and its blank holder
-By inputting the signal from the position detector,
Recognize the actual position and
The wrinkle holding set pressure by the cushion cylinder
After reading from the pressure setting unit,
And output the drive signal corresponding to the set pressure for wrinkle holding
Input the signal from the valve control means and the pressure sensor
The actual pressure of each die cushion cylinder.
It is equipped with a pressure monitor that monitors and displays
Forming press with multi-die cushion
Machine.