Drive for a folder

Information

  • Patent Grant
  • 6776750
  • Patent Number
    6,776,750
  • Date Filed
    Tuesday, May 21, 2002
    22 years ago
  • Date Issued
    Tuesday, August 17, 2004
    20 years ago
Abstract
A low-oscillation and space-saving drive for a changeable format folder of a rotary printing is provided, the rotary printing machine having rotating subassemblies that can be driven, in particular a cutting cylinder, a pin folding blade cylinder, a folding jaw cylinder, a gripper folding blade cylinder, and perforating cylinders belonging to a perforating device. The drive is split up into individual subsystems, and each subsystem is assigned a controlled-position drive motor. In the event of failure of a drive motor, the drive continues to operate without functional impairment.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The invention relates to a drive for a folder of a rotary printing machine having rotating subassemblies that can be driven, in particular a cutting cylinder, a pin folding blade cylinder, a folding jaw cylinder, a gripper folding blade cylinder, and perforating cylinders belonging to a perforating device.




2. Description of the Related Art




U.S. Pat. No. 5,242,367 discloses a folder whose synchronism between the parts is brought about by pairs of gears which are in each case coupled coaxially to one another, the pairs of gears being separated from one another by means of clutches and the pairs of gears being displaced axially for the purpose of changing over the fold or setting the format, in particular adjusting the prefold.




This solution is technically complicated, requires a relatively great amount of space and, because of multiple tooth engagements, is afflicted by rotational play and threatened by wear.




U.S. Pat. No. 5,676,630 discloses a folder with format changing in which cylinder segments of the folding cylinders are rotated with respect to one another by means of two epicyclic gear mechanisms which can be adjusted in relation to each other for the purpose of changing the format.




This solution is technically complicated and, because of multiple tooth engagement, is afflicted by rotational play and threatened by wear.




DE 197 55 428 A1 shows an apparatus for adjusting the folding mechanisms on a folding cylinder of a folder, the adjustment of the cylinder elements bearing folding mechanisms being carried out with two harmonic drive mechanisms in each case connected to the cylinder elements.




The disadvantage is that the drive to the folder is not configured in a low-oscillation manner, and no influence can be exerted on the oscillations which occur.




U.S. Pat. No. 5,901,647 shows a method for the low-oscillation driving of rotating components of a folder, and a low-oscillation folder drive, in each case a motor being assigned to each rotating component, such as perforating rolls, folding jaw cylinders or longitudinal folding devices, and being connected by a form fit to the respective component.




The disadvantage is that in order to adjust the cylinder parts of each cylinder, additional mechanical elements are necessary and, in the event of failure of a motor, the control of the folder initiates a rapid stop for all the rotating subassemblies and the capping of the paper web running into the folder.




SUMMARY OF THE INVENTION




The invention is based on the object of providing a low-wear, space-saving and low-oscillation drive for a folder with changeable format, the intention being to continue to operate the folder without functional impairment in the event of failure of a motor.




This object is fulfilled by splitting up the drive of the folder into a plurality of subsystems wherein each subsystem is assigned a controlled position drive motor.




A particular advantage of the invention is that, as a result of the use of individual controlled-position drive motors on the respective function groups of the folder, such as individual drive motors on the knife cylinder, on the pin folding cylinder, on the folding jaw cylinder and on the perforating device, it is possible for the drive of a folder to be divided up into a plurality of subsystems whose drives are separated from one another.




In addition, as a result of this subdivision of the drive of a folder into a plurality of subsystems whose drives are separated from one another, the transmission of oscillations between the subsystems is minimized.




A further advantage is that the subsystems can be coupled to one another via switchable clutches.




In the event of failure of one of the drive motors, this advantageously permits further operation of the subsystem in which the drive motor has failed, by coupling this “drive-less” subsystem to at least one of the other subsystems, and therefore the serviceability of the entire folder is ensured.




Furthermore, if there is a requirement for a higher torque, for example if there is a requirement for a higher starting torque on the knife cylinder, the subsystems can optionally be coupled to one another via the clutches.




It is advantageous that the individual controlled-position drive motors are used for adjustment functions, such as prefold adjustment or changing over to other types of fold, for example changing over from parallel fold to delta fold or to Z fold and vice versa. It is therefore possible for the mechanical actuating devices providing these adjustment functions for format changing or fold adjustment to be dispensed with.




Furthermore, as a result of the use of the drive motors configured as individual drives, a division of the power in the drive can be carried out, as a result smaller drive motors can be used, which also reduces the dimensioning of the controlled electronics in a corresponding way.




It is significant that, as a result of the use of the individual drives and the subdivision of the mechanical drive train into functional groups, it is possible to exert an active influence on the dynamic system as a folder or as a folding unit via the controlled electronics of the drives. If a plurality of drive motors are used, these can be arranged in the folder in such a way that oscillations which occur are counteracted on the basis of the beneficial, that is to say oscillation-reducing, arrangement of the drive motors in the folder, as a result of which oscillation amplitudes are minimized. Likewise, fold deviations because of oscillations are minimized. Moreover, the oscillations that impair the folding quality are counteracted by the drive control of the motors.




It should also be mentioned that, during steady state operation, all the subsystems can be coupled together and, in this way, by means of defined subdivision of the total drive torque, the gear train consisting of the individual gears engaged with one another is braced. As a result, the multiple tooth engagement in the individual subsystems and in the overall drive train of the folder is no longer subject to rotational play and threatened by wear in steady state operation.




Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

shows a changeable format folder having a cutting cylinder, a pin folding blade cylinder, a folding jaw cylinder or first and second crossfold, a gripper folding blade cylinder and a perforating device for perforating the first and second crossfold, and





FIG. 2

shows the drive of the folding cylinders and their cylinder parts and also the perforating device in a schematic illustration.











DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS





FIG. 1

shows a cutting cylinder


1


for cutting a paper web


2


in interaction with a pin folding blade cylinder


3


, downstream of which a folding jaw cylinder


4


is arranged. The pin folding blade cylinder


3


, interacting with the folding jaw cylinder


4


, produces a crossfold on copies cut by the cutting cylinder


1


. In the event of a further crossfold, a gripper folding blade cylinder


5


cooperates with the folding jaw cylinder


4


. The copies are subsequently delivered in the direction of an arrow by a sheet guide


6


.




Before the cutting cylinder


1


, the paper web


2


runs through a perforating device


36


, for example a perforating device for cross perforation, comprising perforating cylinders


37


and


38


.




The pin folding blade cylinder


3


, the folding jaw cylinder


4


and the gripper folding blade cylinder


5


each comprise two cylinder parts


7


and


8


;


9


and


10


;


11


and


12


which can be adjusted with respect to one another. The cylinder part


7


has three rows of perforating needles


13


, which interact with the cutting knives


14


of the cutting cylinder


1


and are driven by a first controlled-position drive motor


21


arranged on the cutting cylinder


1


. The elements connected to the drive motor


21


, the cutting cylinder


1


and the perforating part


7


of the pin folding blade cylinder


3


, represent a first subsystem A of the drive of the folder (see FIG.


2


).




In the event of a displacement of the fold with respect to the perforating needles


13


, the cylinder part


8


with the folding blades


15


of the pin folding blade cylinder


3


, and the cylinder part


9


of the folding jaw cylinder


4


, fitted with folding jaws


16


, has to be rotated by the same angular amount in order that the folding blades


15


can insert the products, not illustrated, between the folding jaws


16


.




If a second crossfold is made, it is likewise necessary for the cylinder part


11


of the gripping folding blade cylinder


5


, fitted with grippers


17


, to be rotated in order that the grippers


17


can accept the products already crossfolded once from the folding jaws


16


of the cylinder part


9


of the folding jaw cylinder


4


.




The cylinder part


8


fitted with folding blades


15


interacts with the cylinder part


9


fitted with folding jaws


16


and with the cylinder part


11


fitted with grippers


17


, and is driven via a second controlled-position drive motor


25


, which is arranged on the folding jaw cylinder


4


. Alternatively, but not specifically illustrated, the drive motor


25


can also be arranged on the pin folding blade cylinder


3


or on the gripper folding blade cylinder


5


.




The elements connected to the drive motor


25


, the cylinder part


8


with the folding blades


15


, the cylinder part


9


with the folding jaws


16


and the cylinder part


11


with the grippers


17


, represent a second subsystem B of the drive of the folder (see FIG.


2


).




The second crossfold is made by folding blades


18


of the cylinder part


12


of the gripper folding blade cylinder


5


in interaction with folding jaws


19


of the cylinder part


10


of the folding jaw cylinder


4


, the cylinder part


10


and the cylinder part


12


being driven by a third controlled-position drive motor


23


. The drive motor


23


is arranged on the pin folding blade cylinder


3


. Alternatively, but not specifically illustrated, the drive motor


23


can be arranged on the folding jaw cylinder


4


or on the gripper folding blade cylinder


5


.




The elements connected to the drive motor


23


, the cylinder part


10


with the folding jaws and the cylinder part


12


with the folding blades


18


, represent a further subsystem C of the drive of the folder (see FIG.


2


).




Arranged on the perforating cylinder


37


of the perforating device


36


is a drive motor


39


, which drives the perforating cylinder


37


via a drive gear


40


. The perforating cylinder


37


comprises a cylinder part


52


with a perforating knife


41


and a cylinder part


53


with a perforating groove


42


. Arranged on the perforating cylinder


38


of the perforating device


36


is a drive motor


43


, which drives the perforating cylinder


38


via a drive gear


44


. The perforating cylinder


38


comprises a cylinder part


54


with a perforating knife


45


and a cylinder part


55


with a perforating groove


46


.




The perforating knife


45


of the perforating cylinder


38


, arranged on the cylinder part


54


, interacts with the perforating groove


42


of the perforating cylinder


37


, arranged on the cylinder part


53


, in order to provide a perforation for a first crossfold and, with the drive motor


39


, forms a subsystem D of the drive of the folder (see FIG.


2


).




The perforating knife


41


of the perforating cylinder


37


, arranged on the cylinder part


52


, interacts with the perforating groove


46


of the perforating cylinder


38


, arranged on the cylinder part


55


, in order to provide a perforation for a second crossfold and, with the drive motor


43


, forms a subsystem E of the drive of the folder (see FIG.


2


).




The individual subsystems A; B; C; D; E of the drive of the folder with perforating device


36


are explained in more detail in FIG.


2


.




The subsystems A, B and C can be coupled to one another via clutches


33


;


34


;


35


, and the subsystems D and E can be coupled to one another via a clutch


47


.




The subsystem A is driven by the drive motor


21


, which meshes via a drive gear


20


with a drive gear


26


of the cutting cylinder


1


, the drive gear


26


meshes with a drive gear


27


of the cylinder part


7


of the pin folding blade cylinder


3


. The drive gear


27


can be connected, via the clutch


33


, to a drive gear


28


of the cylinder part


8


of the subsystem B.




The subsystem B is driven by a drive motor


25


and is connected to a gear


24


. The drive gear


28


meshes with a drive gear


29


of the cylinder part


9


of the folding jaw cylinder


4


, and the drive gear


29


meshes with a drive gear


30


of the cylinder part


11


of the gripper folding blade cylinder


5


. The drive gear


30


can be connected to the drive gear


32


of the subsystem C via the clutch


35


. The drive gear


30


meshes with the drive gear


24


.




The drive gear


29


of the subsystem B can additionally be coupled, via a clutch


34


, to a drive gear


31


of the cylinder part


10


of the folding jaw cylinder


4


, the drive gear


31


meshing with a drive gear


22


being arranged on a drive motor


23


and being associated with the subsystem C. The drive gear


31


meshes with a drive gear


32


of the cylinder part


12


of the gripper folding blade cylinder


5


.




The subsystem D comprises the drive motor


39


, which meshes, via the drive gear


40


, with a drive gear


50


that drives the cylinder part


53


. The drive gear


50


meshes with a drive gear


51


that drives the cylinder part


54


.




The subsystem E comprises the drive motor


43


which, via the drive gear


44


, meshes with a drive gear


48


that drives the cylinder part


55


. The drive gear


48


meshes with a drive gear


49


that drives the cylinder part


52


.




The subsystems D and E can be coupled to each other via a clutch


47


. In this case, the clutch


47


can be arranged on the drive gear


51


of the subsystem D and the drive gear


48


of the subsystem E and/or on the drive gear


50


of the subsystem D and the drive gear


49


of the subsystem E.




The perforating device


36


can also be configured without a clutch


47


and can be used and operated even without the folder shown.




The adjustment movements of the cylinder parts


7


;


8


and


9


;


10


and


11


;


12


, respectively, registered by sensors


56


;


57


;


58


during the folding adjustment, are fed to a computer


62


coupled to a memory unit


61


containing data and/or to a closed-loop control device


63


and/or to an open-loop control device


64


, which, ensuring automatic fold adjustment, is connected to the drive motors


21


;


23


;


25


and the clutches


33


;


34


;


35


so as to provide signals via connecting lines. The connecting lines are illustrated in schematic form in FIG.


1


and dashed in FIG.


2


.




Furthermore, the positions and adjustment movements, registered by sensors


59


;


60


, of the cylinder parts


52


;


53


;


54


;


55


arranged on the perforating cylinders


37


;


38


of the perforating device


36


in order to carry out the perforation for the first crossfold and, respectively, for the second crossfold are fed to the computer


62


coupled to the memory unit


61


containing data and/or to the closed-loop control device


63


and/or to the open-loop control device


64


, which, carrying out automatic tracking of the perforation, is connected to the drive motors


39


;


43


that drive the perforating device


36


and to the clutch


47


so as to provide signals via connecting lines. The connecting lines are illustrated in schematic form in FIG.


1


and dashed in FIG.


2


.




The clutches (


33


;


34


;


35


;


47


) are connected to the computer


62


so as to exchange signals


65


and data


66


. Via the computer


62


, the closed-loop control device


63


or the open-loop control device


64


, the switchable clutches


33


;


34


;


35


and


47


can be activated or deactivated automatically, depending on the requirement of the torque needed or, in the event of failure of a drive motor


21


;


23


;


25


;


39


;


43


, the coupling of the subsystems can be activated or deactivated automatically.




A variant not specifically illustrated would be for at least one of the subsystems A; B; C to be connected to at least one of the subsystems D; E via a further clutch.




Thus, while there have shown and described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.



Claims
  • 1. A drive system for a folder of a rotary printing machine having rotating subassemblies that can be driven, at least one of said subassemblies having two parts which can rotate coaxially, said drive system comprisinga plurality of subsystems which can be driven independently of each other, each subsystem comprising a respective controlled position drive motor for driving said each subsystem, each subsystem comprising a respective said part of at least one of said subassemblies having two parts, a plurality of clutches for coupling said subsystems to each other, each said clutch coupling said two parts of a respective said subassembly, a memory unit containing data, a computer connected to said memory unit, said computer generating output signals for said drive motors and said clutches, and means connecting said clutches to said computer for exchanging signals and data.
  • 2. A drive system as in claim 1 wherein said clutches are switchable clutches.
  • 3. A drive system as in claim 1 wherein said subassemblies comprise a first subassembly comprising a cutting cylinder, and a second subassembly comprising a pin-folding blade cylinder having first and second cylinder parts, said subsystems comprising a first subsystem comprisinga first controlled position drive motor for driving said first subassembly and far driving said first cylinder part of said second subassembly, and a drive connection between said cutting cylinder and said first cylinder part of said second subassembly.
  • 4. A drive system as in claim 3 wherein said subassemblies further comprise a third subassembly comprising a folding jaw cylinder having first and second cylinder parts, and a fourth subassembly comprising a gripper-folding blade cylinder having first and second cylinder parts, subsystems further comprising a second subsystem comprisinga second controlled position drive motor for driving said second cylinder part of said second subassembly, and for driving said first cylinder part of said third subassembly, and for driving said first cylinder part of said fourth subassembly, a drive connection between said second cylinder part of said second subassembly and said first cylinder part of said third subassembly, and a drive connection between said first cylinder part of said third subassembly and said first cylinder part of said fourth subassembly.
  • 5. A drive system as in claim 4 wherein said subsystems further comprise a third subsystem comprisinga third controlled position drive motor for driving said second cylinder part of said third subassembly, and for driving a second cylinder part of said fourth subassembly which can be rotated coaxially with said first cylinder part of said fourth subassembly, and a drive connection between said second cylinder part of said third subassembly and said second cylinder part of said fourth subassembly.
  • 6. A drive system as in claim 5 wherein said subassemblies further comprise a fifth subassembly comprising a perforating cylinder having a first cylinder part with a perforating groove, and a sixth subassembly comprising a perforating cylinder having a first cylinder part with a perforating knife, said subsystems comprising a fourth subsystem comprisinga fourth controlled position drive motor for driving said first cylinder of said fifth subassembly, and for driving said first cylinder part of said sixth subassembly, and a drive connection between said first cylinder part of said fifth subassembly and said first cylinder part of said sixth subassembly.
  • 7. A drive system as in claim 6 wherein said subsystems further comprise a fifth subsystem comprisinga fifth controlled position drive motor for driving a second cylinder part of said fifth subassembly which is rotatable coaxially with said first cylinder part of said fifth subassembly, and for driving a second cylinder part of said sixth subassembly which is rotatable coaxially with first cylinder part of said sixth subassembly, said second cylinder part of said fifth subassembly having a perforating knife, said second cylinder part of said sixth subassembly having a perforating groove with cooperates with said perforating knife of said second cylinder part of said fifth subassembly, and a drive connection between said second cylinder part of said fifth subassembly and said second cylinder part of said sixth subassembly.
  • 8. A drive system as in claim 7 further comprisingsensors for registering adjusting movements of one of said cylinder parts in each of said second through sixth subassemblies, and for generating input signals, a memory unit containing data, and a computer which processes said input signals and said data, and which generates output signals for said drive motors.
  • 9. A drive system as in claim 5 further comprisingsensors for registering adjusting movements of one of said cylinder parts in each of said second, third, and fourth subassemblies, and for generating input signals, a memory unit containing data, and a computer which processes said input signals and said data, and which generates output signals for said drive motors.
  • 10. A drive system as in claim 1 wherein said means connecting said clutches to said computer comprises at least one of a closed loop control device and an open loop control device.
  • 11. A drive system as in claim 1 further comprising controlled electronics which regulate and control said drive motors, said electronics exerting an active influence on oscillations which occur in said subsystems.
  • 12. A drive system as in claim 1 wherein said subsystems comprise drive gears which can be coupled via said clutches, said system further comprising means for distributing the total drive torque of the system over the drive motors so that mechanical tooth play between the gears is suppressed.
  • 13. A drive system for a folder of a rotary printing machine having rotating subassemblies that can be driven, at least one of said subassemblies having two parts which can rotate coaxially, said subassemblies comprise a first subassembly comprising a cutting cylinder, and a second subassembly comprising a pin-folding blade cylinder having first and second cylinder parts, said drive system comprising:a plurality of subsystems which can be driven independently of each other, each subsystem comprising a respective controlled position drive motor for driving said each subsystem, each subsystem comprising a respective said part of at least one of said subassemblies having two parts, said subsystems comprising a first subsystem comprising: a first controlled position drive motor for driving said first subassembly and for driving said first cylinder part of said second subassembly, and a drive connection between said cutting cylinder and said first cylinder part of said second subassembly.
  • 14. A drive system as in claim 13 further comprising a plurality of clutches for coupling said subsystems to each other, each said clutch coupling said two parts of a respective said subassembly.
  • 15. A drive system as in claim 14 wherein said clutches are switchable clutches.
  • 16. A drive system as in claim 14 further comprising:a memory unit containing data, a computer connected to said memory unit, said computer generating output signals for said drive motors and said clutches, and means connecting said clutches to said computer for exchanging signals and data.
  • 17. A drive system as in claim 16 wherein said means connecting said clutches to said computer comprises at least one of a closed loop control device and an open loop control device.
  • 18. A drive system as in claim 14 wherein said subsystems comprise drive gears which can be coupled via said clutches, said system further comprising means for distributing the total drive torque of the system over the drive motors so that mechanical tooth play between the gears is suppressed.
  • 19. A drive system as in claim 13 wherein said subassemblies further comprise a third subassembly comprising a folding jaw cylinder having first and second cylinder parts, and a fourth subassembly comprising a gripper-folding blade cylinder having first and second cylinder parts, subsystems further comprising a second subsystem comprising:a second controlled position drive motor for driving said second cylinder part of said second subassembly, and for driving said first cylinder part of said third subassembly, and for driving said first cylinder part of said fourth subassembly, a drive connection between said second cylinder part of said second subassembly and said first cylinder part of said third subassembly, and a drive connection between said first cylinder part of said third subassembly and said first cylinder part of said fourth subassembly.
  • 20. A drive system as in claim 19 wherein said subsystems further comprise a third subsystem comprising:a third controlled position drive motor for driving said second cylinder part of said third subassembly, and for driving a second cylinder part of said fourth subassembly which can be rotated coaxially with said first cylinder part of said fourth subassembly, and a drive connection between said second cylinder part of said third subassembly and said second cylinder part of said fourth subassembly.
  • 21. A drive system as in claim 20 wherein said subassemblies further comprise a fifth subassembly comprising a perforating cylinder having a first cylinder part with a perforating groove, and a sixth subassembly comprising a perforating cylinder having a first cylinder part with a perforating knife, said subsystems comprising a fourth subsystem comprising:a fourth controlled position drive motor for driving said first cylinder of said fifth subassembly, and for driving said first cylinder part of said sixth subassembly, and a drive connection between said first cylinder part of said fifth subassembly and said first cylinder part of said sixth subassembly.
  • 22. A drive system as in claim 21 wherein said subsystems further comprise a fifth subsystem comprising:a fifth controlled position drive motor for driving a second cylinder part of said fifth subassembly which is rotatable coaxially with said first cylinder part of said fifth subassembly, and for driving a second cylinder part of said sixth subassembly which is rotatable coaxially with first cylinder part of said sixth subassembly, said second cylinder part of said fifth subassembly having a perforating knife, said second cylinder part of said sixth subassembly having a perforating groove with cooperates with said perforating knife of said second cylinder part of said fifth subassembly, and a drive connection between said second cylinder part of said fifth subassembly and said second cylinder part of said sixth subassembly.
  • 23. A drive system as in claim 22 further comprising:sensors for registering adjusting movements of one of said cylinder parts in each of said second through sixth subassemblies, and for generating input signals, a memory unit containing data, and a computer which processes said input signals and said data, and which generates output signals for said drive motors.
  • 24. A drive system as in claim 20 further comprising:sensors for registering adjusting movements of one of said cylinder parts in each of said second, third, and fourth subassemblies, and for generating input signals, a memory unit containing data, and a computer which processes said input signals and said data, and which generates output signals for said drive motors.
  • 25. A drive system as in claim 13 further comprising controlled electronics which regulate and control said drive motors, said electronics exerting an active influence on oscillations which occur in said subsystems.
Priority Claims (1)
Number Date Country Kind
101 28 122 Jun 2001 DE
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