EP0692377B2 - Method and device for the synchronous driving of printing machine components - Google Patents

Description

The invention relates to a method and a device for the synchronous driving of printing press components by means of coupled drive motors.

Known printing machines for printing web-like materials are equipped with a longitudinal shaft extending along the machine, which ensures precise synchronous operation of one or more drive motors. The drive of the individual components of this machine, e.g. Printing units, folders, Bahnzugorgane and the like., About mechanical transmission and clutches of this longitudinal shaft. Although a synchronous operation of the individual printing press components is achieved, the elastic compliance of the mechanical transmission elements can have an effect on the print quality of the printed product during acceleration or deceleration. Such a mechanical transmission chain with a longitudinal shaft for synchronization is on the one hand very expensive, since many items are required, the transmission chain impeded on the other hand, the accessibility to the individual printing machine components and also makes autonomous use of machine components during set-up operation.

From DE-A 41 38 479 a printing machine without longitudinal shaft is known. The actuators of the printing press components are driven individually with directly mounted drive motors. In this case, while the mechanical transmission chain for synchronization of the printing machine components is saved, but a large number of directly driving motors must be used with correspondingly high-precision controls. This solution is therefore complicated and expensive.

Furthermore, solutions are known in which the elastic compliances of the mechanical transmission elements during acceleration and deceleration of the machine are stabilized by monitoring the position of individual monitoring elements. Examples of this are known from DE 42 10 988 A1 and EP 0 446 641 A2. Although the elastic compliances of the mechanical transfer elements between the printing machine components during acceleration and deceleration can be better controlled with these solutions, the disadvantages of a relatively complex assembly, the poor accessibility and the restrictions on the autonomous operation of printing press components are not eliminated.

DE 33 18 250 A1 teaches a control and regulating device for the synchronous drive of a web-fed rotary printing press with mechanically uncoupled main drive motors. The main drive motors, i. their motor controller, are coupled together for this purpose via a common control line. Via the control line, the engine governors receive their desired value in the form of a so-called reference frequency for setting the desired setpoint speed. At a location in the power transmission path between each of a main drive motor and the driven load, i. the printing machine component, a rotary encoder for detecting the actual speed value is arranged. Its output signal is also routed to the motor controller. The individual engine controllers thus receive a setpoint control signal and an on-site suitable for the engine control actual value from which the engine controller forms the output signal for controlling the respective drive motor according to a suitable control algorithm. Problems will occur in this known engine control when the printing machine components acting as loads have different elasticities. The differences between the measured actual values and the setpoint value supplied via the control line due to the different elasticities of the loads or the transmission elements from the drive motors increase in the unfavorable case from one press component to another, which inevitably leads to distortions and pressure quality-reducing deviations, in particular when accelerating or decelerating the machine leads.

The object of the invention is to enable the synchronous running of printing press components at any time, in particular also during an acceleration phase, for example during the startup of the machine, but also after longer times of the continuous printing.

This object is solved by the subject matters of independent claims 1 and 10.

The respective subordinate claims are directed to advantageous, not completely self-evident embodiments of the invention.

The invention is based on a method for the synchronous driving of printing machine components in which drive motors of printing machine components are coupled to one another by a setpoint control signal and the drive motors coupled in this manner are regulated as a function of a deviation between the setpoint control signal and a suitable actual value signal. The set point control signal may be a speed signal or a position signal, for example an angular position to be set, for the loads, namely the press components, or the drive motors. The actual value signal, referred to as suitable, can be taken off the motor, at a point in the transmission path from the motor to the driven load, or preferably at the torque-free end of this load.

According to the setpoint specification signal is at certain operating conditions, eg. B. Speed changes during startup of the printing press or after plant component inrun operations not easily generated, but is adjusted by an actual value signal of a printing press component. Since the adjusted setpoint control signal assumes the function of coupling between the drive motors and is not simply predetermined from the outside, for example by a corresponding generator of the system control, but is changed depending on the actual, adjusting itself to the press machine actual values according to a suitable control algorithm , the drive motors can be controlled and controlled optimally load-dependent and according to the required accuracy.

The actual value of a printing machine component or a drive motor can be used. At the same time, an actual value signal of a printing machine component and a corresponding actual value signal of an associated drive motor are preferably used to form the setpoint control signal. Together, these two feedback signals contain nearly complete information about the drive-load system of the press engine component and associated drive motor. If, in addition, the differences in the actual value signals of the individual printing machine components are compared with one another and monitored for limit values in continuous printing at constant speed, then, in the case of pure speed control over a longer continuous printing time, accumulating phase position errors can be avoided by suitable control processes.

By forming differential signals between the actual values of the printing machine components to be synchronized and their coupled motors, the different elasticities can be taken into account and corrected as far as possible. By using not only an actual value on the drive motor or on the press component, but both actual values assigned to one another, preferably the phase angle between the two corresponding actual values, a good tooth flank arrangement of the individual links of a multi-part press component, for example a printing group comprising a plurality of cylinders and rollers, can be used. be ensured. The inventive consideration of such an actual-actual difference ensures that never too much elastic energy in the motor load route is.

It proves to be advantageous to use a predetermined master frequency signal as setpoint specification signal and to modulate it with the two actual value signals or the differential signal formed from these two actual value signals to form the setpoint control signal.

The use of actual value signals for the formation of the setpoint control signal is particularly advantageous for accelerating and decelerating the machine as well as for all speed limit limits in integral operations, ie in operating phases in which different elasticities of the press components and different engine characteristics are particularly disadvantageous. It takes place due to the invention throughout the acceleration or Verztigerungsvorgangs acceleration or deceleration smoothing and at the end of both phases, the transition to the constant running, a rounding of the ramp speed in the speed-time diagram running speed of the printing press components. An overshoot of the speed due to the stored elastic energy, which acts in the moment further accelerating to the load in which the drive motor has already passed into constant running, can thus be counteracted smoothing. However, especially in the transition phase, otherwise the web to be printed would be clamped in an unpredictable manner between the individual printing press components.

According to the invention, the control unit selects the actual value signal, which has the greatest deviation from the setpoint specification, or the largest actual / actual difference for forming the setpoint control signal. Thus, a pair consisting of a printing machine component and an associated drive motor is always determined as the master for the synchronization. A simplified embodiment of the system is to form the setpoint control signal based on the difference between a printer component actual value load signal and the unadjusted setpoint setpoint signal.

After a long time of printing, errors in each of the regulated driven printing machine components may gradually accumulate inappropriately. It may happen that the errors between the components compensate somewhat, but because of the never completely preventable drifts of the engine controller, but it can also come to the gradual summation and thus to a drift that must be prevented Therefore, the differences of the actual value -Signals of the individual printing machine components to the setpoint control signal or the differences of the individual actual value signals of the Druckmaschirienkomponenten with each other to exceed a maximum allowable difference checked. If one of the two differences is exceeded, it will be readjusted. This can be avoided by rule Drift over time accumulating errors that have a web drift and not just individual drifting of printing press components result. For this purpose, the system component drive motors can be controlled via an individual setpoint correction signal.

While to be used for the Nachsteuerung If actual values are interrogated periodically by the controller during the acceleration and deceleration phase of the machine, it is generally sufficient to randomly query the relevant actual values in the case of continuously running web in the continuous printing of the machine. As a result, the Nachsteuerungsvorgänge be further reduced in the production.

The present invention can be used in such printing machines, in particular rotary printing machines, whose components, namely the printing units, folders and the like, are additionally mechanically connected, for example via corresponding gear trains. Preferably, however, it is used in autonomously driven printing press components. These printing press components can be driven by several drive motors. In a preferred embodiment, the printing engine components are equipped with a single drive motor or with a main drive motor coupled to the drive motor (s) of other printing machine components by the set point control signal.

It is also advantageous to combine the impression cylinder and its counter-pressure cylinder by mechanical coupling in each case to a pair of cylinders and to drive in pairs by a motor. This is disclosed in the two patent applications P 43 44 896.8-27 and P 44 05 658.3, the teachings of which are related to the combination of cylinders into self-propelled cylinder groups. In this case, the printing press components may also be formed by these cylinder groups. A regulation of such cylinder groups, namely only with a loader, preferably at the torque-free end of the directly driven cylinder is taught by the patent application P 43 44 912.3. This teaching can also be used with advantage in the present invention, it being understood that further actual values of cylinder groups can be used for the synchronization according to the invention.

In the event that in the printing press inking rollers are used, which are not driven by the printing cylinders themselves, but independently, they can be controlled analogous to the system components on the guide frequency and multiplication factors. In this case, the overfeed factors can be predetermined or adapted by the controller as a function of the particular inking roll contact pressure or radius.

The invention will be explained below with reference to a preferred embodiment.

Figur 1

Eine beispielhafte Rotationsdruckmsaschine mit mehreren Druckmaschinenkomponenten;

Figur 2

eine erfindungsgemäße Anordnung zum synchronen Antreiben von in Figur 1 dargestellten Druckmaschinenkomponenten.

In this case, further features and advantages are disclosed. Show it:

FIG. 1

An exemplary rotary printing machine with multiple printing machine components;

FIG. 2

an inventive arrangement for the synchronous driving of printing press components shown in Figure 1.

In Figure 1, a reel changer 2, a biasing unit 3, 4 printing units, a superstructure train 5, a folder 6 and a funnel roller 17 are shown for a conventional web-fed rotary printing press as printing machine components, which are synchronized by a Leitfrequenzkopplung invention. Drive motors 7 with motor encoders 8 and load encoders 9 assigned to these printing press components are also shown.

FIG. 2 shows a regulation and control arrangement for the printing press components 2, 3, 4, 5, 6 and 17. This is a master frequency coupling of the drive motors 7 of the printing press components. For each of the motor controller 10, a motor encoder 8 is provided which outputs a the speed or the position of the respective motor 7 representing the actual value signal I ₁ to the controller 10 of this motor 7 as the second input signal Each engine controller 10 is supplied with a setpoint specification signal V via a line bus 14 from a line frequency generator 12. The speed setpoint command signal V is simultaneously received to all motor controllers 10 via a line bus 14 in real time. From the motor controllers 10, the respective control signal R is formed for each of the drive motors 7 according to a suitable control algorithm. The drive motors 7 then drive their respective printing machine components, in particular the printing units 4, of which only a directly driven blanket cylinder and its impression cylinder are shown in FIG.

At the torque-free end of one of the cylinders of the driven cylinder pair of such a pressure unit 4, preferably at the load-free end of the driven blanket cylinder, the loader 9 is arranged to measure and output a suitable for the control load actual value I ₂ . In the exemplary embodiment, the printing units 4 and the folding unit 6 are equipped with such loaders 9. In principle, it would also be sufficient to provide only the printing units 4 with loaders 9.

Dotted is also the alternative supply of the signal I _{2 of} the load transducer 9 to the respective motor controller 10 located. In this case I ₂ would be used instead of I ₁ for motor control.

In the printing machine components for the web guide, such as reel splitter 2, biasing 3, superstructure roller 5 and hopper roller 17, a play-free direct drive via a corresponding clutch or a toothed belt is possible instead of individual drives. For this reason, one of the donors 8 or 9 can be dispensed with in these components.

The actual values I ₁ and I ₂ of the pairs of motor and load transmitters 8 and 9 are each about Return lines 28 and 29 led to a machine control 13. By the controller 13, the phase shift between the respective pairs of motor encoders 8 and Lastwinkeigebern 9 is monitored.

The motor controller 10 of the printing units 4 and the folder 6 are equipped with address decoders 10.1 so as to be addressed individually by the machine controller 13 can. The actual value signals I ₁ and I ₂ are each fed via a return line 28 and 29 to the machine controller 13. The actual values I ₁ and I _{2 of} the respective system components with one another or the actual value I ₁ or I _{2 of} a single system component for the setpoint specification signal (V) are monitored to determine the drift in the continuous pressure. From this, a correction signal K for the respective printing unit 4 and the folder 6 is formed in each case exceeding predetermined limits and guided by the controller via a line 16 together with an associated address signal via the address decoder 10.1 in the respective motor controller 10. In addition to the address decoders 10.1, the motor controllers 10 of the printing units 4 and the folding unit 6 each have a desired value / actual value comparator 10.2 and a power unit 10.3. The comparator 10.2 of each printing unit 4 and the Falsapparates 6 three signals are supplied, namely the correction signal K via the line 16 and address decoder 10.1, the actual motor value I ₁ and a line 14, the setpoint input signal V from the frequency generator 12. The individual Control is thus formed depending on the transmitted on line 16 correction signal K and the setpoint input signal V on line 14 for each printing unit 4 and the folder 6 in the respective associated motor controllers 10. The control signals are formed from the setpoint control signals S thus formed individually and the individual actual values I ₁ and supplied to the respective motor 7 as control signals R after amplification in the power sections 10. 3 of the motor controllers 10.

When starting the machine, the frequency generator 12 generates the target value command signal V due to the speed command of the controller 13. With the signal returns 28 and 29, the target value command signal V can then according to the acceleration smoothing to the all-coupled press components supplied target value control signal S on the bus 14th be adjusted. At a constant speed, such a global command value control signal S corresponds to the target value command signal V.

For the web guide organs 2, 3, 5 and 17 it is necessary to ensure the correct web train, turn on the setpoint value signal V Voreilungsfaktoren. This is done by the controller 13 and a line bus 15 via the respective motor controllers 10 associated pre-muxing 11 each with an address decoder 11.2 and the actual multiplier 11.1. Instead of the overfeed control, a web tension control according to the prior art can also be used on these web guiding members.

In a further embodiment of the bus structures, the signals (15, 16) can take place via a single bus connection.

In order to compensate for intolerable error summations between the individual printing press components in the production run, the signals of the individually addressable motor and load transmitters 8 and 9 are checked by the controller 13 in a random sampling procedure. Mechanical register adjustments to the printing cylinders are automatically detected by the controller 13 and taken into account accordingly to a higher-level machine program.

For the drift correction in the continuous printing, a query and correction algorithm is advantageously processed by means of a fuzzy logic.

The desired value control signals can be formed centrally according to a likewise preferred embodiment with correspondingly designed machine generator 12 and machine control 13. In this case, address-encoded setpoint control signals S are fed to the motor controllers 10 via the line bus 14. The formation of the desired value control signals S is thereby shifted by the motor controllers 10 to a central unit formed by the generator 12 and the controller 13. Corresponding adjustments would have to be made with regard to the advance multipliers for the railway train authorities.

According to a further simplified embodiment of the invention, the printing units 4 and the folding apparatus 6 are always supplied with the same setpoint control signal S via the bus 14. In this case, the address decoder 10.1 of the motor controller 10 can be omitted.

Claims (21)

1. A method of synchronously driving a first printing machine component (4) by at least a first drive motor (7), and of synchronously driving a second printing machine component (4) by at least a second drive motor (7), in which method

   (a) a common setpoint input signal (V) is used to form a first setpoint control signal (S) and a second setpoint control signal (S);

   (b) a first closed-loop control signal (R) for the closed-loop control of the first drive motor (7) is formed in dependence upon a variation between the first setpoint control signal (S) and an actual-value signal (I₁, I₂) which is representative of the state of rotation of a first motor/load system comprising the first printing machine component (4) and the first drive motor (7), and

   (c) a second closed-loop control signal (R) for the closed-loop control of the second drive motor (7) is formed in dependence upon a variation between the second setpoint control signal (S) and an actual-value signal (I₁, I₂) which is representative of the state of rotation of a second motor/load system comprising the second printing machine component (4) and the second drive motor (7),
   characterised in that

   (d) the common setpoint input signal (V) isadaptedin dependence upon at least one of the actual-value signals (I₁, I₂).
2. A method according to Claim 1, characterised in that the actual-value signal (I₁) of a printing machine component (4) and the actual-value signal (I₂) of a drive motor (7) of the same printing machine component (4) are used to form the setpoint control signal (S).
3. A method according to Claim 1 or Claim 2, characterised in that the actual-value signal (I₁, I₂) used to form the setpoint control signal (S) and the suitable actual-value signal (I₁, I₂) used for the closed-loop control of a drive motor (7) are identical.
4. A method according to Claim 2 or Claim 3, characterised in that a differential signal (I₁-I₂) between the actual-value signal (I₁) of a printing machine component (4) and the actual-value signal (I₂) of the drive motor (7) is used to form the setpoint control signal (S).
5. A method according to any one of the preceding claims, characterised in that the setpoint input signal (V) is frequency-modulated with the actual-value signal or signals (I₁, I₂) or the differential signal (I₁-I₂) to form the setpoint control signal (S).
6. A method according to any one of the preceding claims, characterised in that a setpoint control signal (S) is formed only if a limit is exceeded for a maximum admissible variation between an actual-value signal (I₁, I₂) and the setpoint input signal (V) or for an actual-value differential (I₁-I₂).
7. A method according to any one of Claims 1 to 6, characterised in that

   (a) the actual values (I₁, I₂) of the printing machine components (4, 6) and/or drive motors (7) are scanned,

   (b) the variations between the setpoint value and the scanned actual values (I₁, I₂), or the actual-value differentials (I₁-I₂) between the plant components are established, and

   (c) the variations are then mutually compared and, if admissible limits are exceeded, individual corrective signals (16) are formed for the corresponding plant components.
8. A method according to Claim 7, characterised in that the actual values (I₁, I₂) are scanned in a sampling procedure.
9. A method according to any one of the preceding claims, characterised in that the suitable actual-value signal (I₁, I₂) used for the closed-loop control of a drive motor (7) is an actual-value signal of this drive motor (7) or is a [lacuna] at a zero-torque extremity of the printing machine component (4) driven by this motor.
10. Apparatus for synchronously driving a first printing machine component (4) by at least a first drive motor (7), and for synchronously driving a second printing machine component (4) by at least a second drive motor (7), with

    (a) at least a first actual-value encoder (8, 9) for the output of a first actual-value signal (I1, I2), which is representative of the state of rotation of a first motor/load system comprising the first printing machine component (4) and the first drive motor (7), and at least a second actual-value encoder (8,9) for the output of a second actual-value signal (I1, I2), which is representative of the state of rotation of a second motor/load system comprising the second printing machine component (4) and the second drive motor (7),

    (b) a first closed-loop motor controller (10) for the closed-loop control of the first drive motor (7) and a second closed-loop motor controller (10) for the closed-loop control of the second drive motor (7),

    (c) a control means (12, 13) for the output of a setpoint input signal (V), which is fed to the first and the second closed-loop motor controller (10),

    (d) the first closed-loop motor controller (10) using the setpoint input signal (V) to form a setpoint control signal (S) and, in dependence upon a variation between this setpoint control signal (S) and the first actual-value signal (I₁, I₂), forming a closed-loop control signal (R) for the closed-loop control of the first drive motor (7), and

    (e) the second closed-loop motor controller (10) using the setpoint input signal (V) likewise to form a setpoint control signal (S) and, in dependence upon a variation between this setpoint control signal (S) and the second actual-value signal (I₁, I₂), forming a closed-loop control signal (R) for the closed-loop control of the second drive motor (7),
    characterised in that

    (f) the first and second actual-value signal (I₁, I₂) is fed via at least one feedback line (28, 29) to the control means (12, 13), which adapts the setpoint input signal (V) in dependence upon at least one of the actual-value signals (I₁, I₂).
11. Apparatus according to Claim 10, characterised in that, for a printing machine component (4), there is provided an actual-value encoder (9) for the output of an actual value of the printing machine component (4) and there is provided an actual-value encoder (8) for the output of an actual motor value.
12. Apparatus according to Claim 11, characterised in that each printing machine component (4) has a pair of actual-value encoders (8, 9).
13. Apparatus according to any one of Claims 10 to 12, characterised in that each of the actual-value encoders (8, 9) is connected via a feedback line (28, 29) to the controller (13).
14. Apparatus according to any one of Claims 10 to 13, characterised in that there is provided a comparator circuit which, on the input side, establishes the actual values (I₁, I₂) and/or the setpoint input signal (V) in order to establish the maximum variation between the actual values (I₁, I₂) or between one of the actual values (I₁, I₂) and the setpoint input, and in that the maximum variation value undergoes further processing.
15. Apparatus according to any one of Claims 10 to 14, characterised in that the unit for generation of the setpoint control signal (S) comprises a controller (13) and a frequency generator (12) connected thereto, the controller (13) modulating on the setpoint input signal (V), which is generated by the frequency generator (12), for the formation of the setpoint control signal (S) a signal which represents a differential signal formed from an actual value (I₁) of a motor encoder (8) or an actual value (I₂) of a load encoder (9) of a first printing unit (4) to an actual value (I₁) of a motor encoder (8) or an actual value (I₂) of a load encoder (9) of a second printing unit (4).
16. Apparatus according to any one of Claims 10 to 15, characterised in that the unit for generation of the setpoint control signal (S) comprises a controller (13) and a frequency generator (12) connected thereto, the controller (13) modulating on the setpoint input signal (V), which is generated by the frequency generator (12), for the formation of the setpoint control signal (S) a signal which represents a differential signal formed from an actual value (I₁) of a motor encoder (8) or an actual value (I₂) of a load encoder (9) of a printing unit (4) to the setpoint input signal (V).
17. Apparatus according to any one of claims 10 to 16, characterised in that there is fed to the closed-loop motor controllers (10), via a line (14), a setpoint input signal (V) from a frequency generator (12) and, via a further line (16), a corrective signal (K) from a machine controller (13).
18. Apparatus according to Claim 17, characterised in that the closed-loop motor controllers (10) each have an address decoder (10.1) to which the corrective signal (K) is fed, and a setpoint value/actual value comparator (10.2), to which are fed the setpoint input signal (V) and, via the address decoder (10.1), the corrective signal (K) to form the setpoint control signal (S).
19. A rotary printing machine, characterised by apparatus according to any one of Claims 10 to 18.
20. A rotary printing machine according to Claim 19, characterised in that only actual-value signals (I₁, I₂) are fed back from actual-value encoders (8, 9) of one or of a plurality of cylinders, in particular from mechanically coupled cylinder pairs, each of which is driven by at least one motor (7), from printing units (4) or from drive motors (7) thereof.
21. A rotary printing machine according to Claim 20, characterised in that other printing machine components, in particular the web guide components (2, 3, 5, 16), have, in addition to the closed-loop motor controller (10), an advance multiplier (11) to which the controller (13) applies advance signals via a further control line (15) in order to ensure adequate web draw.

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