JPH10328899A - Method for slide control of press machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the precision of a product and to prolong the life of a dies by decreasing the impact and vibration generated at the top dead center, bottom dead center and the starting point of forming at the time of ascending or discending of a slide. SOLUTION: The input parameter 3 is normalized by the press starting signal 6 according to the time of transmission from the time-generator 4 and is inputted into an electronic cam 2, and then, by the slide motion command outputted from the electronic cam 2, the descending region from the top dead center S0 to the starting point of forming S1 in the slide motion diagram, the forming region from the starting point of forming S1 to the bottom dead center S2 and the pressurizing retension region, and the ascending region from the bottom dead center S2 to the top dead center S0 are each constituted on a smooth continuous cam curve and the locational control of the slide is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slide control method for a press machine used for position control of a slide, and a method in which a large impact or vibration is generated in a press machine at each turning point such as starting, starting and stopping. Prevent and smooth control,
It is also effective for increasing the accuracy.

[0002]

2. Description of the Related Art In the prior art, slide position control in a slide motion of a press machine has generated a slide motion by combining a plurality of constant velocity lines. The slide motion in the position control of the slide of the hydraulic press in the related art includes, for example, a descending region from a top dead center Z00 to a forming start point Z10 shown in FIG.
From molding start point Z10 to bottom dead center Z20 and bottom dead center Z20
, The forming area and the pressure holding area up to the rising start point, and the rising area from the rising start point of the bottom dead center Z20 to Z30 and the rising area from Z30 to the top dead center Z00 are connected by straight lines, respectively, and a plurality of slide motions are connected. It was generated by a combination of velocity lines.

[0003]

As described above, when the slide motion is generated by combining the constant velocity lines, the velocity change is large and abruptly occurs at each break point of the constant velocity lines. And the accompanying vibration occurs. Further, when the speed change is large, a large power is required, and the slide motion cannot follow the control command value. In addition, at the molding start point, there is a problem that the mold and the blank, and the collision between the mold and the mold via the blank occur, shortening the life of the mold, generating noise and defective products.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, to make the top dead center, the bottom dead center, and the forming start point of the slide motion continuous with a smooth curve, and to prevent the occurrence of shock and vibration in a press machine slide. It is to provide a control method.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a slide control method for a press machine, wherein a position command value of the slide motion is sequentially synthesized with one or more electronic cam curves. Generated by In addition, the descending region from the top dead center to the molding start point of the slide motion, the molding region and the pressure holding region from the molding start point to the bottom dead center, and the ascending region from the bottom dead center to the top dead center, respectively. It is controlled by a slide motion command that is constituted by a smoothly continuous cam curve. Further, the cam curves in the above-mentioned respective regions are respectively set as independent modified sine.

[0006]

1 to 5 show one embodiment of a slide control method of a hydraulic press according to the present invention. FIG.
Indicates a slide motion generating unit 1 according to the present invention, wherein an input parameter 3 set in advance and an output of a time generator 4 are input to an electronic cam 2, and the output is displayed on a display 5 as a slide stroke diagram. . The output t of the time t generator 4 indicates that the press start signal 6 is O
It increases monotonically at N, and is reset every time one stroke ends. In the input parameter 3, a time t from the start of the stroke at the top dead center S0 and a corresponding slide stroke are set. For example, at the molding start point S1, T1 = 3 (seconds) and S1 = 80 ( mm), bottom dead center S
2, T2 = 6 (seconds), S2 = 100 (mm),
After pressing and holding from T2 = 6 (seconds) to T3 = 7 (seconds) at bottom dead center S2, return to top dead center S0, T4 = 10 (seconds), S
One stroke ends at 0 = 0 (mm). The slide stroke diagram displayed on the display 5 sequentially connects a cam curve 7 in a descending area, a cam curve 8 in a forming area, and a cam curve 9 in an ascending area based on a slide motion command generated by the electronic cam 2 described later. It will be combined. In this case, the cam curve 7 in the descending area, the cam curve 8 in the forming area, and the cam curve 9 in the ascending area are each independently deformed sine, but may be another smoothly continuous cam curve. The slide performs a slide motion along the cam curve 7 in the descending area, the cam curve 8 in the forming area, and the cam curve 9 in the ascending area, and slides at respective elapsed times T0, T1, T2, T3, and T4 in the slide motion. The speed of the stroke is zero, and starting and stopping without impact are possible.

FIG. 2 shows an overall configuration of the present invention, in which a slide 11 connected to a piston 10A of a hydraulic cylinder 10 of a hydraulic press has a cap C Pressure release valve 13,
It is driven as pressure oil is supplied and discharged from the hydraulic source 15 via the pilot check valve 14. The stroke of the slide 11 is detected by the slide position detector 16 and fed back to the controller 17. The slide position signal and the slide motion generator 1 in the controller 17
Are compared with each other to obtain a deviation signal e, which is subjected to various calculations by a position controller 17A composed of a PID controller or the like.
2 and slide 11 so that the deviation signal e becomes zero.
Is controlled so that the slide motion follows the command value of the slide motion generation unit 1.

FIG. 3 is a block diagram showing the configuration of the electronic cam 2 shown in FIG. 1. The three-dimensional block includes a deformed sine generating block 19A for the descending region, a deformed sine generating block 19B for the forming region, and a deformed sine generating block 19C for the rising region. The cam curve 7 in the descending region shown in FIG.
Command values corresponding to the cam curve 8 in the forming area and the cam curve 9 in the ascending area are output.

FIG. 4 shows the configuration of the modified sine generation block 19, which outputs a cam displacement s at time t when an arbitrary cam rise time th and a maximum displacement h are set. Here, the block 20 outputs a normalized change S with respect to the normalized time T, and includes a first block ms1 shown in FIG. 5A and a second block ms shown in FIG. 5B.
s2 and the calculation result (normalized change S) of each of the third blocks ms3 shown in FIG. 5C is switched and output according to the normalized time T. Before and after block 20, t →
A conversion process of T, S → s is performed. The modified sine generation block 19A in the descending area, the modified sine generation block 19B in the forming area, and the modified sine block rise 19C in the ascending area shown in FIG.
9 is used.

In the above-described embodiment of the present invention, the press machine is a hydraulic press. However, the present invention is not limited to this.

[0011]

As is apparent from the above description, according to the present invention, from top dead center S0 to molding start point S1, from molding start point S1 to bottom dead center S2, and from bottom dead center S2 to top dead center. Since the cam curves up to the point S0 are generated with independent deformed sine and are made continuous, at the time of starting, stopping, and starting the forming of the slide motion, the state is smoothly continued from the state of zero speed or to the state of zero speed. I can do it. Therefore, the slide motion has almost no impact and vibration, extends the life of the mold, and reduces the noise of the press machine.
The occurrence of product defects can be prevented. Along with this, high-speed operation of the press machine becomes possible, and effects such as improvement in productivity are obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a slide motion generation unit according to an embodiment of the present invention.

FIG. 2 is an overall configuration diagram

FIG. 3 is an electronic cam block diagram.

FIG. 4 is also a modified sine generation block diagram.

FIG. 5A is a diagram showing a first example of the switching unit in FIG. 4;
Block diagram (b) Similarly, second block diagram of the switching unit in FIG. 4 (c) Similarly, third block diagram of the switching unit in FIG.

FIG. 6 is a slide motion diagram in a conventional example.

[Explanation of symbols]

1 is a slide motion generator, 2 is an electronic cam, 3 is an input parameter, 4 is a time generator, 5 is a display, 6
Is a press start signal, 7, 8, 9 are cam curves, 10 is a hydraulic cylinder, 10A is a piston, 11 is a slide, 12 is a servo valve, 13 is a cap pressure release valve, 14 is a pilot check valve, 15 is a hydraulic pressure source, 16 is a slide position detector, 17 is a controller, 17A is a position control controller, 18 is a servo amplifier, 19 is a modified sine generation block, 19A is a modified sine generation block of a descending region, 19B
Is a modified sine generation block for the forming area, 19C is a modified sine generation block for the ascending area, 20 is a switching unit, t is the output of the time t generator, S0 is top dead center, S1 is a molding start point, S
2 is bottom dead center, e is a deviation signal, s is cam displacement, T is normalized time, S is normalized displacement, ms1 is the first block, ms2
Is a second block, and ms3 is a third block.

Claims (3)

[Claims] In a slide control method for a press machine,
A slide control method for a press machine, wherein the position command value of the slide motion is generated by sequentially combining one or more electronic cam curves. 2. A sliding region from a top dead center to a molding start point of a slide motion, a molding region and a pressure holding region from a molding start point to a bottom dead center, and a top dead center from a bottom dead center. A slide control method for a press machine, wherein a rising area up to a point is controlled by a slide motion command for forming a smoothly continuous cam curve. 3. The slide control method for a press machine according to claim 2, wherein the cam curves in each of the regions are independently modified sine.