EP0904934A1 - Device and method for driving printing machines with a plurality of independent driving motors - Google Patents

Abstract

The sheet-fed printing press has at least one transfer station (10), with its own and adjustable drive (12), between the press units (2,3). Angle measurement sensors (7'.7.9'.9) control the transfer station (10), and the transfer control station (10) is also controlled by sensors which register the ends of the paper sheets.The transfer station (10) can be mechanically disengaged, has angled sides, and can be brought into a collision-free setting.

Description

1. In einen die verschiedenen Druckwerke verbindenden Räderzug oder Antriebswelle speisen mehrere Motoren ein vorgegebenes Drehmoment ein. Durch den Räderzug wird die Synchronisierung der verschiedenen Druckwerke gewährleistet. Mittels einem Überschuß an Drehmoment ergibt sich eine ständige Zahnflankenanlage, wodurch eine gute Druckqualität gewährleistet werden soll. Nachteilig dabei ist, daß eine elastische Verformung der Zahnräder bereits für eine merkliche Verschlechterung der Druckqualität sorgt, da aufgrund von ständig schwankendem Lastmoment die exakte Einspeisung des gerade benötigten Drehmoments nicht gewährleistet werden kann. Eine entsprechende Vorrichtung geht aus der DE OS 1 563 591 hervor.

2. Die Druckwerke werden in separate Abschnitte eingeteilt, die mittels Einzelantrieb so angetrieben werden können, daß innerhalb der Druckwerksabschnitte nur geringe elastische Verformung der Zahnräder erfolgt. Die einzelnen Druckwerksabschnitte werden so zueinander synchronisiert, daß eine exakte Übergabe der Papierbogen gewährleistet wird. Der Nachteil dieser Vorrichtung besteht darin, daß die einzelnen Druckwerksabschnitte eine sehr große Masse haben die zusätzlich über eine Umdrehung betrachtet unterschiedliche Lastmomente aufnehmen. Daraus ergibt sich, daß es einer sehr komplizierten Regelung bedarf um die Druckqualität zu erzielen, die von Maschinen mit Einzelantrieb bekannt ist. Als Alternative dazu wird in der DE 41 37 979 A1 vorgeschlagen, die eigentliche Regelung auf eine winkelsynchrone Übergabe der Druckbogen zu beschränken. Das heißt, es wird nur in einem bestimmten Winkelbereich um den Übergabepunkt geregelt und aüßerhalb dieses Winkelbereiches erfolgt nur eine Konstanthaltung der Drehzahl. Dadurch werden zwar die Zeitbedingungen für die Regelung erleichtert, aber die Drehmassen bleiben unverändert groß.

The invention relates to a device and a method for driving printing machines with a multi-motor drive. Multiple drives on printing presses are known from the prior art by the following patents:

1. Several motors feed a predetermined torque into a gear train or drive shaft connecting the various printing units. The synchronization of the different printing units is guaranteed by the gear train. An excess of torque results in a constant tooth flank system, which should ensure good print quality. The disadvantage here is that an elastic deformation of the gears already leads to a noticeable deterioration in the print quality, since due to constantly fluctuating load torque, the exact supply of the torque just required cannot be guaranteed. A corresponding device can be found in DE OS 1 563 591.

2. The printing units are divided into separate sections which can be driven by means of individual drives in such a way that only slight elastic deformation of the gears takes place within the printing unit sections. The individual printing unit sections are synchronized with one another in such a way that an exact transfer of the paper sheets is ensured. The disadvantage of this device is that the individual printing unit sections have a very large mass, which additionally take up different load moments when viewed over one revolution. It follows that a very complicated regulation is required in order to achieve the print quality which is known from machines with a single drive. As an alternative to this, it is proposed in DE 41 37 979 A1 to restrict the actual regulation to an angularly synchronous transfer of the printed sheets. This means that it is only regulated in a certain angular range around the transfer point and outside of this angular range only the speed is kept constant. The time conditions for the regulation are thereby made easier, but the turning masses remain unchanged.

The object of the invention is to propose a device and a method, which improves the disadvantages known from the prior art.

According to the invention this is solved by the features of claims 1 and 11.

An advantage of the invention is that the separately driven transfer station Machine is decoupled on the one hand and remains easily controllable on the other hand.

The remaining groups of printing units in front of and behind the separation are respectively conventional gear train connected and each with a drive. By the separation, the strung printing units have a favorable Vibration behavior. This means that the resonance frequency of the printing unit groups is still as it is high that there is still no vibration excitation at maximum production speed. The regulation of these drives does not have to be coordinated so precisely with one another to achieve phase-accurate paper transfer. That is, a phase shift can be caused by the Transfer station are balanced. This means there are no quick control interventions in the drive the printing units in front of and behind the transfer station necessary, which causes control vibrations can be avoided and the press delivers good printing results. The one now occurring The phase shift of the separated printing units is controlled by a control of the transfer station balanced. That means the transfer station takes the sheet of paper from the one in front Printing group on phase-synchronized, corrects the phase position during the rotary movement for handover to the printing group behind and hand over the sheet phase-synchronized to the printing group behind.

The rapid control of the transfer station is possible because the mass of the transfer station is small and no mechanical effect on the groups of printing units in front and behind is exercised. In addition, motors can be used because of the low Load torque also have favorable control properties. Drives are particularly suitable for this, which are attached directly to the shaft of the transfer station.

The transfer station is implemented, for example, by a transfer cylinder or transferter. It is known from the prior art to design the transfer cylinder as one-turn, the is called the development (sheet plus channel) of the impression cylinder and the transfer cylinder identical. Furthermore, it is known the transfer cylinder as a so-called storage drum to be carried out by the same half-or three-speed and thus the double or has three times the circumference of the printing cylinder. At most, the scope of the Transfer cylinder with the circumference of the printing cylinder in an integer ratio.

Due to the elimination of the mechanical coupling, the integer ratio is not mandatory necessary. On the contrary, for example, two and a half times the size of the Transfer cylinder has the advantage that the angle of rotation range, in the phase correction can be made is larger. It is also conceivable that through the channel caused space between two arcs to use for phase correction.

For example, the transfer station rotates with the sheet after it has been picked up Circumferential speed like all cylinders in front. This ensures that the Sheet experiences no relative movement to its transport medium and therefore the risk of There is no lubrication. If the sheet is outside the printing nip or outside the contact surface of the printing unit, it can accelerate or be delayed until an exact alignment of the phase of the transfer cylinder with the phase of the subsequent printing unit groups. The rotary motion of the transfer station is accordingly not continuously, but modulated depending on the diameter and phase correction.

The time of takeover and the time of handover are not advantageous identical, but are placed so that in the meantime the possibility of Phase correction first on the printing group and behind the transfer station then insists on the group of printing units located in front of the transfer station.

An additional advantage of the invention is that by adjusting the phase relationship Register corrections can be made. A targeted phase shift when taking over and / or transfer can be used to make the paper edge larger in the gripper closure or smaller, which allows the register to be adjusted. The same applies in the case of Use of the device according to the invention when turning the bow. That is, the Transfer station takes the place of the previous turning drum. As is well known at the The rear edge of the sheet is taken over and this is done when changing from Beautifully made on reverse printing and various settings for different formats must be done by simply changing the program at the push of a button. This means the downtimes when converting the machine when changing jobs significantly shortened.

Previous concerns that the synchronism of the machine components is lost in the event of a control failure and thus collisions in the gripper area lead to machine damage can be eliminated by the device according to the invention and a correspondingly executed method. When a transfer station is used as the transfer station, which has flattened sides due to its design, it can be moved to a position in which the front or rear printing unit groups cannot do any damage. In the event of a power failure, the power supply can be ensured by converting the kinetic energy in generator operation.
This safety position can also be approached when the machine is shut down in order to enable the printing unit groups to move independently for setup, washing, etc. This can reduce the set-up time.

The arrangement of the device according to the invention can be used wherever Printing unit groups or individual printing units lined up by a transferter become.

Another variant provides for the mechanical coupling between the printing unit groups by means of a gear train and to assign a separate drive to a transfer station. The In this case, the transfer station can also be a single transfer cylinder. The drive provides for the fact that when a sheet is taken over from the printing group in front of it, a exact tooth flank system is produced for this. In principle, this is Method also for a phase correction of the transfer station to the respective Printing unit groups, but within smaller angular ranges. When handing over the sheet from the transfer station to the printing unit groups behind it, one is corresponding exact tooth flank system made for these. A corresponding solution is by means of suitable sensors for differential angle measurement or torque measurement systems. The difference angle measurement can be done, for example, by means of two incremental encoders, each are attached directly to the units involved in the sheet handover become. A defined regulated angle difference is within the limits of the elastic one Deformation of the gears in a proportional relationship with the transmitted one Torque.

The divided printing unit groups are regulated by their regulation so that they act like separate machines without taking care that the torque flow in the transition area is rectified. The intermediate transfer unit has the task of producing the tooth flank system in the right direction.
Specifically, this means that in the case of sheet transfer from the printing group in front of it to the transfer station, a torque flow must be directed in the direction of the transfer station. If the situation so requires, this can be made possible by applying a braking torque to the transfer station by means of its drive.

In the case of sheet transfer from the transfer station to the one behind Printing unit group becomes a moment flow in the direction of the one behind Printing unit group generated, which is applied by the drive of the transfer station.

The term printing unit group is not limited to a grouping of Printing units, but also includes a combination of printing unit and feeder or Printing unit and delivery. The same applies to paint shops or similar units that treat an arch inline.

Fig. 1

zeigt eine schematische Anordnung der erfindungsgemäßen Vorrichtung,

Fig. 2

zeigt ein Blockschaltbild der Antriebsregelung,

Fig. 3

zeigt ein Strukurbild der Antriebsregelung,

Fig. 4

zeigt ein Ablaufdiagramm der Regelstrategie,

Fig. 5

zeigt den Geschwindigkeitsverlauf des Transferters.

The invention is explained in more detail with reference to FIGS. 1 and 2.

Fig. 1

shows a schematic arrangement of the device according to the invention,

Fig. 2

shows a block diagram of the drive control,

Fig. 3

shows a structure diagram of the drive control,

Fig. 4

shows a flow chart of the control strategy,

Fig. 5

shows the speed curve of the transferter.

Figure 1 shows a printing press 1 with a plurality of printing units arranged in series 2 or 3. A sheet to be printed is fed by the feeder 4, through the printing units 2 and 3 to transported to the boom 5. The printing units 2 and the feeder 4 are by a gear train connected to each other, which is represented by an arrow 6. The drive of this Printing unit group 2 together with feeder 4 is carried out by a motor 7. The printing units 3 together with the boom 5 are also connected to one another by a gear train, which is represented by an arrow 8. The drive for this printing group 3 together with the boom 5 is accomplished by a motor. Between the two Printing unit groups 2 and 3 is a transfer station 10, which is mechanically from the Wheel trains of both printing unit groups 2 and 3 is decoupled. An arrow 11 indicates the function the transfer station 10 between the printing unit groups 2 and 3. The transfer station 10 is represented by a transferter in the example. However, this can be any act sheet transport device. The transfer station 10 is operated by a motor 12 driven, the angular position feedback takes place by an incremental encoder 12 '. The Angular position of the other two motors 7, 9 takes place by means of incremental encoders 7 ', 9'. All Motors 7,9,12 are provided by according to the required power Power units 13, 13 ', 13' 'supplied.

The control of the three motors 7, 9, 12 is implemented by a control device 14. Their The task is to so the motors 7 and 9 according to a predetermined target speed regulate that predetermined angle difference between the two printing unit groups 2 and 3 is not is exceeded. The maximum difference depends on the dynamics of the drive system Transfer station 10 from. Furthermore, the task of the control device 14 is to Time of the sheet transfer, the transfer station 10 in exact phase agreement with the last sheet-guiding cylinder or drum of the printing group 2 in front and at the time of the sheet transfer, the transfer station 10 in exact phase correspondence with the first sheet-guiding drum or cylinder of the subsequent printing group 3 bring to.

An input device 15 connected upstream of the control device 14 outputs the various Setpoints such as speed, moving to a certain angular position, Acceleration and braking function or the like before.

It could be advantageous for the device according to the invention, additional incremental encoders 7 ″ or 9 ″ in each case at the sheet guiding directly adjacent to the transfer station 10 Attach cylinder or drum. Alternatively, it is also conceivable to use incremental encoders 7 ' and 9 'instead of the torque feed cylinder, the adjacent cylinders to the Assign transfer station.

Fig. 2 shows a block diagram of the drive control. A setpoint generator 20 provides one Angle setpoint phi Soll, a speed specification n Soll, and an acceleration setpoint a Soll. These values are fed to the drive control 21, 21 'and 21' ', respectively. The Drive control 21 is assigned to a power unit 13, which supplies a motor 7. Of the Motor 7 forms the drive for printing unit group 2. The specification is made accordingly the values phi soll, n soll and a soll for the drive control 21 'which is connected to the power section 13 'is connected and together with the motor 9 the drive for the printing group 3 represents.

The same applies to drive control 21 ″, power section 13 ″ and motor 12, these Components for driving the transfer 10 are responsible. The respective Deliver incremental encoder 7 ', 9', 12 'assigned to printing unit groups 2, 3 or transferter 10 their values, which correspond to their respective angular positions, to the drive control 21 ″, which also contains information about the construction-related transfer position of the Receives paper sheet. Alternatively, it is also possible to determine the position of the sheet edge or the position the gripper and the like Using a sensor to record and this measured variable as the actual value for the Use the handover rule. A combination of position sensor and Incremental encoder. The transfer position 22 defines the angular position at which one Transfer of a sheet from printing group 2 to Transferter 10 takes place. Through the Transfer position 23 is defined at which angular position a transfer from the transferter 10 to printing unit group 3. The transfer positions are due to the mechanical Contraction specified, but can be determined by the sheet format in reverse printing become.

Einen Proportionalregler 24, 25 der als Lageregler eingesetzt wird. Kp stellt dabei den proportionalen Verstärkungsfaktor dar.

Einen Proportional-Intergralregler 26 als Geschwindigkeitsregler mit dem Verstärkungsfaktor Kpi.

Die Strecke 27, wobei Ks die Streckenverstärkung und Ts die Zeitkonstante der Strecke darstellen.

28 stellt eine Rechenoperation dar, wobei aus dem Drehzahlistwert n der Winkelistwert phi gebildet wird. S ist dabei der Laplace-Operator.

Fig. 3 shows the structure of the drive control, as is known according to the prior art. The setpoint generator 20 supplies the setpoints phi setpoint, n setpoint and a setpoint to the controller as a reference variable. The controlled variables are formed by the actual speed value n and the actual angle value phi, which are formed by evaluating the incremental encoders 7 ', 9', 12 '. The individual components of the controller or the line show:

A proportional controller 24, 25 which is used as a position controller. Kp represents the proportional gain factor.

A proportional integral controller 26 as a speed controller with the gain factor Kpi.

The route 27, where Ks represent the route gain and Ts the time constant of the route.

28 represents a computing operation, the actual angle value phi being formed from the actual speed value n. S is the Laplace operator.

Fig. 4 shows a flow diagram showing the interaction of the transfer 10 with the Printer groups 2 and 3 shows. An area is defined in which a regulation of the Position of the transfer 10 takes place on the position of the printing group 2 and a second Area in which a regulation of the position of the transferter 10 to the position of the Printing group 3 takes place. In doing so, a for the controller of the transferter Angle setpoint phi setpoint, a speed setpoint n setpoint and an acceleration setpoint a setpoint calculated and in a further step a regulation of the angle difference is achieved.

5 shows a diagram which shows the speed curve of the transferter 10 over the Period of a sheet transport shows. That is, within this period the arc of the printing group 2 taken over, transported and then to printing group 3 passed on. There are three different speed profiles through the Curves 30, 31, 32 shown.

Curve 30 shows a constant speed, which is caused by the fact that between there is no phase shift in printing unit groups 2 and 3. The Transferter 10 has in this If the task has its speed exactly on the value of the two printing unit groups 2, 3 hold to ensure an angularly synchronous transfer of the sheet.

Curve 31, like curve 30, shows a constant speed curve up to time T ₁ . Up to the time T ₁ , a transported sheet is still in contact with the drum or the cylinder, which is arranged in front of the transferter 10. If the transferter 10 were accelerated or decelerated in this period, the sheet could be smeared. Therefore, the transferter 10 moves within this critical angular range with the same peripheral speed as the last drum or the last cylinder of the printing unit group 2. From time T ₁ , the sheet is completely on the transferter 10, so that the phase correction can be carried out. In curve 31 there is an acceleration from T ₁ , ie the transferter 10 catches up with an existing differential angle with respect to the subsequent printing unit group 3. From time T ₂ , an angular synchronism with the subsequent printing group 3 is established and the transferter 10 moves at a constant or with the same peripheral speed as the following printing group 3. In the period between T ₂ and T ₃ , the transfer of sheet 10 from transfer group 10 to the printing group 3 can take place . This can take place, for example, by means of spa controls known from the prior art. From time T ₃ to time T ₄ , the transferter 10 is braked. During this braking, the transferter 10 again decreases the difference angle that it has caught up in the period T ₁ , T ₂ . From T ₄ , an angular synchronism between the transferter 10 and the printing group 2 is then established again, and an arc-synchronous transfer of a sheet from printing group 2 to the transferter 10 can take place. From time T ₄ , the process is repeated, the amplitude of the curve, ie the acceleration or deceleration of the transferter 10, can have different values depending on the height of the difference angle.

Curve 31 describes the case where there is a positive difference angle from printing group 2 to printing group 3, ie printing group 3 is leading compared to printing group 2. Curve 32 describes the reverse case, ie printing group 2 lags printing group 3. Therefore, between T ₁ and T _{2 there is} first a deceleration of the transferter 10 and subsequently an acceleration between T ₃ and T ₄ .

Reference list

1

Printing press

2nd

Printing unit

3rd

Printing unit

4th

Investors

5

boom

6

arrow

7

engine

7 '

Incremental encoder

7 ''

Incremental encoder

8th

arrow

9

engine

9 '

Incremental encoder

9 ''

Incremental encoder

10th

Transfer station / transferter

11

arrow

12th

engine

12 '

Incremental encoder

13

Power section

13 '

Power section

13 ''

Power section

14

Control device

15

Input device

20th

Setpoint generator

21

Drive control

21 '

Drive control

21 ''

Drive control

22

Transfer position

23

Transfer position

Claims (12)

Device for synchronizing at least two printing unit groups (2, 3) representing a sheet-fed printing press 1, each printing unit group 2, 3 being driven by at least one separate drive motor (7, 9) and gear train,
characterized,
that at least one transfer station (10) with a separately controllable drive (12) is provided between the printing unit groups (2, 3). Device according to claim 1,
characterized,
that angle measuring sensors (7 ', 7'',9', 9 '', 12 ') are provided for controlling the transfer station (10). Device according to claim 1,
characterized,
that sensors for monitoring the sheet edge are provided to regulate the transfer station (10). Device according to claim 1,
characterized,
that the transfer station (10) is mechanically decoupled. Device according to claim 1,
characterized,
that the transfer station (10) has flattened sides. Device according to claim 5,
characterized,
that the transfer station (10) can be brought into a collision-free position. Device according to claim 1,
characterized,
that the transfer station (10) is a transferter. Device according to claim 1,
characterized,
that the transfer station (10) is a turning drum. Device according to claim 1,
characterized,
that the transfer station (10) is mechanically coupled. Device according to claim 9,
characterized,
that torque and angle measuring sensors (7 ', 7'',9', 9 '', 12 ') are provided for controlling the tooth flank system. Method for the synchronous transfer of printed sheets between two printing unit groups (2, 3) driven by a separate drive, by means of a transfer station (10),
characterized,
that the transfer station (10) between the two printing unit groups first establishes phase synchronism with the printing group (2) in front of it and then phase synchronism with the printing group (3) behind it. A method according to claim 10,
characterized,
that the phase synchronism is carried out by defined contact of the tooth flanks between the gears of the printing group (2) in front of it and the transfer station and then between the gears of the printing group behind it and the transfer station (10).

Images