JPS63297042A - Ink supply quantity controller per zone - Google Patents

Abstract

PURPOSE:To ensure the detection of step-out to make a control condition with high accuracy and stability, by a method wherein a drive pulse is issued to each stepping motor and the occurrence of error in the control of the stepping motor is detected when a pulse signal is not normally generated from a corresponding waveform shaping circuit according the drive pulse. CONSTITUTION:If the increase/decrease of blade open amount is directed by switches 111-11n, a CPU 21 issues data directing which blade open amount should be increased, decreased, and this data is imparted to a CPU 31. After selecting a DRV 4 to be controlled by sending a selection signal MC through an I/F 36, the CPU 31 sends a forward or reverse rotation pulse PF or PR from an I/F 35 as a pulse number according to the increase or decrease of blade open amount, whereby a stepping motor (STM) 41 rotates to conduct the increase/decrease of blade open amount. A pulse generator 42 also rotates to issue pulse signals phia, phib and a detection signal H according to the drive current conduction through a DV 54. With the normal generation of signals phiA, phiB, the CPU 31 judges a control condition to be normal without the step- out in the STM 41 and judges a drive condition to be also normal according to the detection signal H.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a device for electrically controlling the amount of ink supplied for each zone divided in the horizontal direction of a printing plate mounted on a printing cylinder of a printing press. It is related to.

[Conventional technology]

In a printing press, in order to continuously supply an appropriate amount of ink to the printing plates mounted on the printing cylinder, a blade is provided for each zone of the printing plate, facing the ink roller of the ink fountain, and the connection between the ink roller and each blade is The amount of ink supply is determined for each zone of the printing plate by adjusting the amount of opening between each blade depending on the image pattern on the printing plate.In order to do this by remote control, conventionally, A motor is provided to adjust the opening amount, as well as a potentiometer that converts the opening amount into an electrical signal, and these constitute a DC servo control circuit that uses the opening amount as a feedback signal, thereby controlling the ink supply amount for each zone. I am doing it.

However, with the above-mentioned configuration, the durability of the servo motor and potentiometer, changes in characteristics over time, impedance fluctuations of connection lines, electrical noise, etc. are affected, and control accuracy and stability are insufficient. .

As a countermeasure to this problem, instead of the analog control described above, it is possible to use a step motor control circuit, digitalize the control circuit, and use open-loop control or closed-loop control.

However, in open-loop control, if the step motor does not rotate in accordance with the applied drive pulse and causes a correction, the ink supply amount will not be adjusted as planned, and the control of the ink will be inaccurate or impossible. However, since there is a risk of printing defects, it is necessary to use closed-loop control.

In other words, the control origin is detected by a sensor and control is performed based on this, or the opening is detected as an electric signal by a potentiometer as in the past, or the rotational status of a motor such as a rotary encoder is detected. , it has become common to use these detection outputs as feedback signals.

[Problem that the invention seeks to solve]

However, even in closed-loop control, when the control origin is detected by a sensor, closed-loop control cannot be achieved with control variables other than the control point, and the adjustment of the step motor cannot be detected. When using a p10 encoder, etc., the durability is poor and the detection accuracy is limited, making it impossible to control with high stability and precision. Rounding that generates rotational torque pulsation and punching operation, punching pulses are generated from rotary encoders, etc., and the counting status of this is inaccurate.
This leads to problems such as control errors.

[Means for solving problems]

In order to solve the above-mentioned problem, the present invention is constructed by the following means.

In other words, in the above-mentioned control device, there is a step motor provided for each blade that adjusts the snacking of each blade, and a two-phase pulse motor connected to each step motor and each corresponding to the rotation. A pulse generator that generates signals, a waveform shaping circuit that is provided corresponding to each pulse generator and that shapes two-phase pulse signals into pulse signals using hysteresis characteristics, and sends driving pulses to each step motor. The apparatus also includes a control means for detecting that an error has occurred in the control of the step motor when a pulse signal is not normally generated from the corresponding waveform shaping circuit in response to the driving pulse.

[Effect]

When the step motor rotates in response to the drive pulse, the pulse generator sends out a two-phase pulse signal, which is converted into a two-phase pulse signal by the waveform shaping circuit. In addition to being able to determine whether the motor is rotating accurately, the waveform shaping circuit has hysteresis characteristics, so even if the step motor loses synchronization or hunting occurs in the pulse signal from the pulse generator, the waveform remains unchanged. There is almost no hunting in the output pulse of the shaping circuit, and since it is a two-phase pulse, the direction of rotation can be detected, so it can be accurately determined that the situation in which this occurs is irregular. As a result, it is possible to immediately detect that an error has occurred in the control of the step motor.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to figures showing examples.

FIG. 1 is a block diagram showing the configuration, and an operation panel (hereinafter referred to as 0P) 1 includes switches 111 to 111 for adjusting the blade opening amount corresponding to each zone divided in the left and right direction of the printing plate.
are provided, and above, facing these, is a display 121 such as a bar display that displays the opening of each blade.
12n is provided, and the main control unit (hereinafter referred to as MCT) 2 connected to this is centered around a processor (hereinafter referred to as CPU) 21 such as a microprocessor, and a ROM (Read
0nly Memor)', ) and RAM (Rand
om Aecesa Memory, > by Meshichiri (
22 (hereinafter referred to as MM) and an interface (hereinafter referred to as
I/F') 23 to 25 are arranged around the bus line 26.
When connected, the CPU 21 uses the ROM of the MM22.
Execute the instruction stored in
Predetermined data processing is performed while accessing the RAM of M22.

In addition, the sub-control unit (hereinafter referred to as 5CT) 3 connected via the I/F 24″Ik of the MCT 2 is also connected to a CPU similar to the CPU 21.
U31 , + MM32 similar to MM22, and I
/Fs 33 to 36, which are connected by a bus 3T, and the CPU 31 performs predetermined control through the same processing operations as the CPU 21.

For these, drive units (hereinafter referred to as DRY) 41 to 4n are provided for each blade of the ink fountain.
switches 111 to 11n and indicators 121 to 12n
A step motor (hereinafter referred to as STM) 41 that adjusts the snacking of each blade of the ink fountain individually, and a pulse generator such as a resolver connected thereto (hereinafter referred to as STM) pc) 42e is provided, and in response to the selection signal MC sent from the I/F 36 of the 5CT3 being applied via the buffer 43t, the gates 46 to 52 of the C are turned on, and the I/F 35t of the 5CT3 turns on.
- According to the forward rotation pulse PF or reverse rotation pulse PR sent through the excitation pattern generator (hereinafter, E
Based on the excitation signal generated by the PG) 53, a driver (hereinafter referred to as DR) 54 drives the 87M41 t-, causing it to rotate in a stepwise manner.

In response to this rotation, the PG42 also rotates at the same time and generates two-phase pulsed signals φa and φb with a 90° phase difference similar to a two-phase rotary encoder. It has hysteresis characteristics and undergoes waveform shaping by 9 AND gates 44 and 45, and after becoming two-phase pulse signals φA and φB, the I/F of 8CT3
Given to 34.

9. A resistor R is inserted in the power return path of the DR54, and the terminal voltage of this generated in accordance with the flow of the drive current of the 87M41 is the excitation detection signal H via the gate 48't of the DR54.
It is sent as 8CT3's I/F34.

Therefore, if you instruct the switches 111 to 11n of the OPl to increase or decrease the opening amount of the blade, this data will be transferred to the I/F2.
3 to the CPU 21, and in response, the CPU
21 sends data on which blade snack should be increased or decreased through the I/F 24t, which is the I/F 24t.
When given to CPU31 via F33t-, CPU31
DRY to be controlled by sending the selection signal MC through the I/F 36t to 41: Upon selection, the forward rotation pulse PF or the reverse rotation pulse PRt is sent from the I/F 35 as the number of pulses according to the amount of increase or decrease in opening. This allows the 87M4 to be sent via the EPG53 and DR54t.
1 is driven, 87M41 rotates in steps according to the number of pulses, and the blade snacking is adjusted.

Then, the PG42 also rotates in synchronization with the rotation of the PG 87M41, and sends out pulse-like signals φa and φbl indicating its status, and also sends out a detection signal H in accordance with the drive current flowing through the DR54. If the pulse signal φB via F34 is generated normally, 87M4
The sub-control unit determines that no step-out has occurred in 1 and that the control status is normal, and also determines that the driving status is normal in response to the 1 detection signal H, and determines whether an error has occurred. , 2- occurs, an error signal is sent to the main control section, and the main control section receives the signal and displays the error.

The blade opening amount display on OPl is shown by switch 11 on OPl.
This is the value commanded from 1 to 11 m.

The above control is repeatedly performed at high speed for each DRY (s to 4n), and each DRY41 to DRY is repeatedly operated at high speed in response to the operation of the switches 111 to 11n of OPl.
4nK is controlled and displayed on the display devices 121 to 12n.

Note that the I/F 25 is used for exchanging data with other parts, and the CPU 21 also performs processing corresponding to this data.

FIG. 2 is a perspective view showing the structure of DRY4.
is fixed, 1 is directly connected to this, and PG4 is
2 is fixed, a gear 63 is engaged with a shaft passing through a mounting plate 61 of a gear box 62, and a gear 64 that engages with the gear 63 is used to adjust the blade opening amount in a known manner (not shown in the figure). It is what drives the mechanism.

9. There is a support 65 on the STM41 side of the mounting plate 61.
7M41 etc. and it is fixed and protrudes a thousand steps, this S
A printed circuit board 66 on which various circuits of the DRV4 shown in FIG. 1 are mounted is secured to the TM41 side.

FIG. 3 is a flowchart of the control situation mainly performed by CPυ31 of 5CT3. First, check the "Set motor error flag? After performing “selection of the relevant motor” 102 by sending out “1
PF or PR transmission for steps 111 sends driving pulses by the number of pulses required for 87M41 to rotate one step, and the pulse signal ``φ person, φB・Regular? J 112
to judge.

When the result of step 112 is Y (YE8), MM3
After carrying out [Updating current position data by 1 step] 121 in 2, when the selection signal MC is stopped, [stopping the relevant motor selection J122t-] is carried out, and from step 101 onwards for the next ranking 8TM41 via r END J. Repeat.

Concerning the above, if step 112 is N, pulse signals φA and φB are not generated normally, 87M41 is out of synchronization, and corresponding to step 101 [the motor error flag-set 4131 t-does not occur] , and MCT2
Data indicating the error is sent to the OPl, and the corresponding display 12 of the OPl is blinked or the display color is changed using the "motor error display" 132 to notify the operator of the occurrence of a control abnormality.

Therefore, the step-out of the 87M41 can be detected immediately and reliably, and appropriate countermeasures can be taken before a large number of printing defects occur due to abnormalities in the control of holes and ink supply. can.

However, PO42 generates a two-phase pulse signal φa.

Even if a hunting pulse occurs during the occurrence of φb'6, the deviation from vA can be accurately detected.

In addition, since the two-phase pulse signals φA and φB are used only to detect step-out, it is not a closed loop control, and there is no control error caused by noise, etc., and the 8TM41 is not forced by some external force. When it is rotated, the rotation direction and rotation angle are indicated by each pulse signal φA and φB, so the position deviation is determined by comparing with the data in MM32, and the position deviation is corrected accordingly. is optional.

Furthermore, 87M41 does not have a brush, and PO22 does not have a mechanical contact such as a potentiometer, which improves overall durability and stability, and provides high reliability.

On the other hand, by using 87M41, opening control is accurate, and if the number of steps of 87M41 is t - 10 times or more for the minimum unit operation command, control accuracy and reproducibility will improve, and DRV4 will have better control performance. There is no mechanical restriction on the origin, and the control origin can be set independently of the adjustment origin of the blade opening amount adjustment mechanism.

In addition, if it is directly combined with PG42tSTM41, 87
There is no delay in the generation of the pulse signals φa and φb corresponding to the rotation of M41, and the detection status based on this is quick.

However, it is also possible to use 8TM41 as an ultrasonic drive motor, or to use PO42t as a photoelectric pulse encoder, omitting the printed circuit board 66 in FIG.
It may be housed integrally in Ta, and as shown in FIGS.
The configuration of the figure can be freely modified in various ways, such as being arbitrarily selected depending on the conditions.

In addition, with some modifications, it can also be applied to plate register adjustment, paper size presetting, etc. in printing machines.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, when controlling the ink supply amount by zone based on the opening of the blade using a step motor, step-out can be reliably detected, and the control status can be controlled with high precision and high accuracy. Because of the stability,
A remarkable effect can be obtained in controlling the ink supply amount by zone of various printing machines.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, with FIG. 1 being a block diagram showing the configuration, FIG. 2 being a perspective view of the drive section, and FIG. 3 being a flowchart of the control situation. 1・Book・-op (operation board), 2 Bone...MCT (main control unit), 3...5CT (subcontrol unit), 41~4n
φ...DRv (drive unit), 21.31...CPU
(processor), 22, 32... Sake MM (memory),
41...Fist/STM (step motor), 42...War/PG (pulse generator), 44~52-...AND gate, MC fist---Selection signal, PF...Forward rotation pulse, PR-φ... Reverse pulse, φa, φb--Pulse signal, φA. φB II m-・Pulse signal.

Claims (1)

[Claims] In a device that controls the ink supply amount for each zone by adjusting the opening amount of each blade provided in each zone divided in the left and right direction of the printing plate by a motor, A step motor that individually adjusts the opening amount, a pulse generator that is connected to each step motor and generates a two-phase pulse signal in accordance with the rotation, and is provided corresponding to each pulse generator. A waveform shaping circuit that shapes the pulsed signal into a pulse signal using a hysteresis characteristic, and a waveform shaping circuit that sends driving pulses to each of the step motors and outputs a pulse signal normally from the corresponding waveform shaping circuit according to the driving pulse. 1. A zone-specific ink supply amount control device, comprising: a control means for detecting that an error has occurred in the control of the step motor when an error does not occur.