JPH05213505A - Roller drive control method - Google Patents

Abstract

PURPOSE:To perform electrical adjustment without requiring intervention of a continuously variable transmission and the like when a peripheral speed change is generated. CONSTITUTION:An upper and a lower roller 1a, 1b are respectively provided with servomotors 11a, 11b for individual drive. One of the rollers is phase- controlled with a high gain and the other roller is speed-controlled by means of proportional control with a low gain, and the speed-control side roller is used as a helper of a drooping characteristic so as to prevent a machinery damage due to decrease of torque competition between both the servomotors. Total phase-control is accomplished by the phase-controlled roller, and in the case of a printing roller and a punching cutter, for example, a proportional gain of the speed-controlled roller is further decreased only in the section wherein the upper and the lower roller 1a, 1b are in contact with each other, so that effect of simultaneous phase synchronization can be further enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roll stand on the final stage which has a mechanism such as a rotary punching cutter which does not slip with each other and may have different diameters in the process of manufacturing a corrugated box. The lower rolls are individually driven by the motors, and all rolls are synchronized phase control at the same speed of the upper and lower rolls of the printing machine such as the roll stand up to the preceding stage. The present invention relates to a roll drive control method for speed adjustment.

[0002]

2. Description of the Related Art In contrast to the conventional line shaft system of this type, a servo motor is installed for each roll stand,
A so-called "electronic shaft" sectional drive method that allows accurate operation while maintaining the phase relationship between the roll stands has already been developed and put into practical use.
No. 90680 [Title of Invention / Tuning Phase Control Device for Servo System, Filing Date / July 20, 1990] is proposed [hereinafter, referred to as "prior example"].

FIG. 3 is a block diagram showing the circuit configuration of this prior art example. Between the upper roll 2b and the lower roll 2a of the rotary punching cutter 2, the printed sheet 4 [which is a corrugated board for a corrugated cardboard box] of the work piece whose surface is printed via the printing rolls 1a and 1b [ Although illustration is omitted,
When the sheet to be printed 4 has a gap when it is not bitten], the blade provided on the lower roll 2a bites into the resin surface coated on the outer peripheral surface of the upper roll 2b to be embedded in the sheet to be printed 4 Punched out and conveyed to the next step. Printing roll 1a for the first and second roll stands
1b is driven by servomotors 11a and 11b, respectively, and rotations from the drive shafts of the motors 11a and 11b are directly transmitted to one roll shaft and transmitted to the other roll shaft through the continuously variable transmission 3. It The rotational positions of the servo motors 11a and 11b are taken out as speed / position pulses by the pulse encoders 12a and 12b. The printed sheet 4 is shown as a short single sheet for the sake of understanding, but it is continuous up to the rotary punching cutter 2 of the final roll stand, and is synchronized with the rotational phase of each rotor. Transferred between the rotors. Further, one of the upper roll 2b and the lower roll 2a of the rotary punching cutter 2 of the final stage roll stand is directly connected and driven by the servo motor 11c,
The other is indirect connection drive via the continuously variable transmission 3. The rotation position of the servo motor 11c is the pulse encoder 12c.
Are extracted as velocity / position pulses. These servo motors 11a, 11b and 11c are
The speed is controlled by the drivers 13a, 13b and 13c, and it is equipped with an automatic torque controller (Automatic TorqueController) and an automatic speed controller (Automatic Speed Controller). Speed servo control is performed by negatively feeding back the position pulse.

Further, the speed to each roller set by the speed setting digital switch (DSW) is given to the controller 21a through the switch 22a, and the soft starter 22 [takes time on the horizontal axis and speed on the vertical axis]. It is a means that can automatically control the speed if only the steady speed, start signal, and stop signal are given so that the characteristic diagram starts smoothly, moves to the steady speed, and stops smoothly.]
The speed command Vref is output to each servo driver that drives each servo motor. In the position command generating circuits 26a, 26b and 26c to which this speed command Vref is input, the speed command Vref
convert ref to position commands Xref1, Xref2 and Xref3,
Position pulses 15a, 15b and 15c from the previous pulse encoders 12a, 12b and 12c are counted by the counter (CTR), and the position command Xref is used as feedback position signals 27a, 27b and 27c.
1, Deviations from Xref2 and Xref3 are calculated, and proportionally integrated (PI) to obtain the speed command V from the soft starter 22.
In addition to ref, the digital amount of the operation result output in these controllers 21a is determined by the servo drivers 13a, 13b and 13a.
It is converted into an analog quantity suitable for the calculation of c, and the rotation speed command (Nref) 14a, 14b of each servo motor 11a, 11b and 11c.
And 14c for each servo driver 13a, 13b and
Given to 13c. In such a control system, the servo motors 11a, 11b and 11c driven by the servo drivers 13a, 13b and 13c respectively operate via the continuously variable transmission 3 connected to the motor rotation shaft to print roller 1a, 1
The rotary punching cutter 2 provided with b and a blade are respectively rotated in the directions of the arrows shown in the drawing, the sheet 4 to be printed is printed, and punched into the required shape.

By the way, each roll
The upper and lower rolls on the stand are paired and driven by the servo motors 11a, 11b and 11c, which are the same drive source.
If the diameter of the lower roll is different, or if the peripheral surface is shaved from the viewpoint of maintenance in the process of use, the change in peripheral speed due to the decrease in diameter may cause a change in the precision continuously variable transmission 3 installed between the upper and lower rolls A mechanical adjustment device is indispensable, it is expensive, the mechanism is complicated, it occupies a large space, and
There was a difficulty that the adjustment work itself was complicated. Here, the present invention is an improved roll drive control method for solving these problems, and of course it can be applied to a printing roll that is a roll stand of the first stage or the intermediate stage, but for example, the final stage When the rotary punch cutter of the roll stand is used, the upper and lower rolls do not slip with each other, and the upper and lower rolls that may have different diameters are individually driven by their servo motors. The purpose is to provide a method.

[0005]

In order to achieve the above objects, the present invention provides a series of roll stand processing lines in which a plurality of upper and lower rolls for biting a workpiece are formed in a line, When the workpieces flowing in the line from the upper and lower rolls of the first roll stand move to the upper and lower rolls of the final roll stand while being processed, the upper and lower rolls of the final roll stand The upper and lower rolls of one or more roll stands follow a constant speed command, and the motors that drive the upper and lower rolls perform high gain phase control all at once, The upper and lower rolls of the remaining roll stands are equipped with servo motors for each of the upper and lower rolls for individual drive, and the servo motors that drive one roll are Servo motor for performing the rotation phase control of the in, the other roll is a roll drive control method characterized by performing speed control by proportional control of low gain, further, in the roll drive control method according to the preceding paragraph. , The upper and lower rolls are driven individually.The servo motor that drives the other roll has a low gain during the fixed time when the work is bitten by the upper and lower rolls of the roll stand and the specific work is performed. It is a roll drive control method characterized in that the gain of speed control by proportional control is further lowered to perform speed control by proportional control.

[0006]

According to the present invention having such a method, slip does not occur between the upper and lower rolls that are individually driven, and the speed control side roll also has a role as a helper having a drooping characteristic in terms of torque with respect to a change in speed. That is, it is used as a means to help lower the speed of the lower roll, prevents damage to the machine due to reduction of torque competition between the motors of both upper and lower rolls, and adjusts when changing the roll diameter by the roll diameter setting switch. This is possible only by changing the settings, and the machine configuration is extremely simple and simple.

[0007]

1 is a block diagram showing the circuit configuration of a printing apparatus equipped with a punching cutter as a specific embodiment of the present invention, and FIG. 2 is a detailed explanatory view of its essential parts.
In all the drawings, the same reference numerals indicate the same or corresponding members. Now, according to the flow of the work process, the printing target sheet (for example, cardboard) 4 printed by the printing rolls 1a and 1b of the first and second roll stands is matched with the pattern of the printing, It is punched in the rotary punching cutter 2 of the stand according to the shape of the box. Therefore, the printing rolls 1a and 1b and the rotary punching roll 2 are based on the tuned phase control that operates while keeping the rotational phase relationship of each servo motor from beginning to end. Here, the lower roll 2a of the rotary punching cutter roll 2 has a blade, and the upper roll 2b is a receiving cylinder. Further, no slip occurs between the upper and lower rolls in the punching section. Servo motors 11d and 11c are respectively installed on the rotary shafts of the upper roll 2b and the lower roll 2a of the rotary punching cutter 2 to drive them individually. And each servo motor 11a,
The rotary axes of 11b, 11c and 11d are each servo driver 13a,
Driven by 13b, 13c and 13d, each servo driver 13a, 13b, 13c and 13d has an automatic torque regulator (ATR) and an automatic speed regulator (ASR) respectively, and
Each servo motor 11a, 11b, 11c and 11d has a pulse encoder for speed and rotational position feedback.
12a, 12b, 12c and 12d are connected. Then, the controller 21 controls each servo driver 13a, 13b, 13c and
Rotation speed command for each motor to 13d 14a, 14b, 14c and 14d
And the function of giving an adjustment command of velocity gain and an acceleration command in the punching section to the upper roll 2b of the rotary punching cutter 2.
As input signal means to the controller 21, a speed setting digital switch (DSW) 31 for instructing the speed of each servo motor, and the rotation of the servo motor 11d corresponding to the change in the diameter of the roll 2b on the rotary punching cutter. In order to keep track of the number, the diameter of the upper roll 2b of the rotary punching cutter can be set. Upper roll diameter (D)
It also has a setting digital switch (DSW). The printing roll 1a and the printing roll 1b, which are the first-stage and second-stage (intermediate stage) roll stands, are the same as the control means shown in FIG.

By the way, the gist of the present invention is that the speed of each roll of the rotary punching cutter 2 in which the upper and lower rolls 2b and 2a are individually driven by separate servo motors without using a continuously variable transmission. Position control consists in applying a unique means. That is, the servo motor 11c of the lower roll 2a is controlled by the same speed and rotational position as in the case of the preceding example of FIG. 3, but the continuously variable transmission is not mounted.
As one means, the servo motor 11 of the upper roll 2b
c is driven by the servo driver 13d, detects a feedback pulse that is both a speed pulse and a position pulse from the pulse encoder 12d, and this feedback pulse is detected by the servo driver.
Negative feedback to 13d, the rotation speed command from controller 21 14d
Then, the deviation between and is derived to perform closed-loop control of the speed, and this feedback pulse is used separately for rotational position display and the like via the counter 24d. The other means is to add an acceleration command, which is the speed setting digital
When the speed set by the switch 31 is given to the soft starter 22 by turning on the switch 22a, the speed that gradually changes from a slow speed increase to a steady speed at the set speed and then a slow speed is decreased by a stop command Regarding command Vref, positive / negative acceleration command dv when speed is changing
/ dt (v is velocity and t is time) is output. Secondly, regarding the speed gain adjustment, as shown in FIG. 2, the position command X input from the position command generating circuit 26c is input.
According to ref3, the input / output characteristics preset in the speed proportional gain switching circuit 29 [the position signals X1 and X2 corresponding to the position of the lower roll blade are plotted on the horizontal axis and the automatic speed regulator (AS
R) represents the speed proportional gain P]], and as a discrete output signal Do of the speed proportional gain switching circuit 29 composed of the discrete circuit, this is also a servo driver composed of the discrete circuit. As the discrete input signal Di of 13d, the speed proportional gain P of the automatic speed regulator (ASR) of the servo driver 13d is adjusted, and the punching sections X1 to X2 of the print sheet 4 are slightly marked before and after the fear.
The gain P is reduced by a constant value in the range including the gin section. Further, as a third speed adjusting means, the speed command Vref from the soft starter 22 to the servo motor 11d is compared with the initial diameter of the upper roll as a constant value.
It is given once to the division circuit 28 that calculates the ratio with the current diameter set by the upper roll diameter setting setting digital switch 32, and the speed command is proportionally increased to
The rotation speed 14d is applied to the servo driver 13d via the analog converter 23e. In this way, when the diameter of the rotary punching cutter upper roll 2b is reduced due to the peripheral surface cutting or the like, the rotary punching cutter upper roll 2b is cut.
The diameter (D) can be freely set by the digital switch 32 for setting the diameter (D) of the roller, and the increase in the rotation speed of the upper roll driving servo motor 11d is calculated by the ratio of (initial diameter / D),
I try to match the peripheral speed.

However, even if the diameter is artificially set rigorously, due to a subtle difference in peripheral speed, a torque competition occurs between the drive motors 11d and 11c of the upper and lower rolls 2b and 2a of the rotary punching cutter 2. It may occur, causing damage to the blade of the rotary punching cutter lower roll 2a.
In order to prevent the decrease of the roll speed in such a case, the servo drive of one rotary punch lower cutter roll 2a performs speed control by high gain PI control and, as its major loop, controls other print rolls. Equivalent high-gain phase control is performed, and the other roll 2b on the rotary punching cutter is only speed control by low-gain proportional control, and the phase loop major loop is not configured. In addition, acceleration / deceleration compensation (torque / compensation) is added to the rotary punch cutter upper roll 2b side to ensure command followability during line acceleration / deceleration.

In this way, in this embodiment of the present invention, the rotational phase of the punching section of the rotary punching cutter 2 is secured by the high gain phase control of the lower roll 2a.
Meanwhile, the upper roll 2b side plays a role of a helper having a drooping characteristic. Furthermore, in order to ensure this effect, the proportional gain of the speed control on the upper roll 2b side is reduced during the punching section, and after the cutter blade is removed and punching is completed, the proportional gain is increased to accelerate the speed variation due to negative load fluctuation. Raise. The rotation phase of the punching section is the position command X of the lower roll 2a.
It is constantly managed by ref3 and outputs a proportional gain switching signal to the servo controller 13d.

[0011]

As described above, according to the present invention, in a series of roll processing lines formed by arranging a plurality of upper and lower rolls for biting a workpiece, one or more of them are formed. With regard to the roll stand, the upper and lower rolls that do not cause slippage are individually driven by the servo motors, making adjustments when the diameter changes only by setting the upper roll diameter with a digital switch, making it extremely easy. In addition, mechanical structures such as expensive precision continuously variable transmissions can be removed,
The price can be reduced. Furthermore, the reliability is also improved by the simplification of the mechanism and the less secular change compared with the mechanical method.

[Brief description of drawings]

In one embodiment of the present invention, the upper and lower rolls of the roll stand from the first stage to the next stage are driven by one servo motor and a continuously variable transmission, respectively,
The block diagram showing the circuit configuration that performs simultaneous phase tuning control on the roll stands from the first stage to the final stage while individually driving the upper and lower rolls of the stand with separate servo motors without a continuously variable transmission.

FIG. 2 is an explanatory diagram showing details of a main part of FIG.

FIG. 3 is a block diagram showing a circuit configuration to which a sectional drive method of driving a servo motor for each roll stand in which a pair of upper and lower rolls of the preceding example is applied.

[Explanation of symbols]

 1a Printing roll 1b Printing roll 2 Rotary punching cutter 2a Rotary punching cutter Lower roll 2b Rotary punching cutter Upper roll 3 Continuously variable transmission (mechanical) 4 Workpiece (printing sheet) 11a Servo motor 11b Servo motor 11c Servo・ Motor 11d Servo motor 12a Pulse encoder 12b Pulse encoder 12c Pulse encoder 12d Pulse encoder 13a Servo driver 13b Servo driver 13c Servo driver 13d Servo driver 14a Revolution command 14b Revolution command 14c Revolution command 14d Speed command 15a Speed / position (feedback) pulse 15b Speed / position (feedback) pulse 15c Speed / position (feedback) pulse 15d Speed / position (feedback) pulse 16 Acceleration command (analog amount) 21 Controller 21a Controller 22 Soft starter 23a Digital to analog conversion 23b Digital-analog converter 23c Digital-analog converter 23d Digital-analog converter 23e Digital-analog converter 24a Counter 24b Counter 24c Counter 24d Counter 26a Position command generator 26b Position command generator 26c Position command generator 27a Feedback Position signal 27b Return position signal 27c Return position signal 28 Division circuit (initial diameter / current diameter) 29 Speed control proportional gain switching circuit 31 Speed setting digital switch 32 Upper roll diameter setting digital switch

Claims (2)

[Claims] 1. A processing line for a series of roll stands in which a plurality of upper and lower rolls for biting a workpiece are formed side by side in a row, and the workpieces flowing through the line from the upper and lower rolls of the first stage roll stand. One or more roll stands up / down rolls up to the top / bottom rolls of the final roll stand are fixed when the material is transferred to the top / bottom rolls of the final roll stand while being processed. The motors that drive the upper and lower rolls perform high gain phase control all at once according to the speed command, and the upper and lower rolls of the remaining roll stands up to the final roll stand are the upper and lower rolls. Servo motors are installed in each of the above to perform individual drive, and the servo motors that drive one roll perform the simultaneous high-gain rotation phase control of the previous rolls and drive the other roll. Servomotor roll drive control method characterized in that the speed control by proportional control of the low gain. 2. The roll drive control method according to claim 1, wherein the upper and lower rolls are individually driven, and
Within a certain period of time when the work is bitten by the lower roll and a specific work is performed, the servo motor driving the other roll lowers the gain of speed control by proportional control of low gain and lowers it by proportional control. A roll drive control method characterized by performing speed control.