EP1464490B1 - Method for loading and exchanging the cylinders of the printing groups of a printing machine and apparatus for implementing said method - Google Patents

Abstract

The procedure involves bringing a screened cylinder (17) from a loading station (16) to a storing station (14) or a reserve station (11), using a transport carriage (18). The cylinder is loaded on a transport device (13) using a robot (19) to bring the cylinder to a work position (10a). The cylinder is replaced by bringing it to an unloading position from where the cylinder is moved to one of the stations (11, 14, 16). An independent claim is also included for a device for charging and exchanging the cylinders of printing groups of a printing machine.

Description

The present invention relates to a method for loading and exchanging the cylinders of printing units of a printing machine and to a device for carrying out the method.

Generally, a printing machine has several printer groups arranged, for example in the case of an online flexographic printer, one after the other. In this type of machine, each printer unit comprises a platen roller on which the ink is deposited by a screen cylinder, commonly called "anilox cylinder" by practitioners. This screen cylinder is inked, in a well known manner, by means of either a scribe chamber or an inking cylinder associated with an inkwell. The forme cylinder prints directly, by contact, the material to be printed, this using a press roll applying the material to be printed against the forme cylinder. The screen rolls have, at their circumference, cavities for retaining the ink to be deposited on the cliché of the forme cylinder. The volume, per unit area, of these cells varies according to the work that one wishes to achieve. Thus, it will be necessary to provide the use of different screen rolls for each specific work that is desired to achieve. This necessarily involves the exchange of these screened cylinders according to the print quality that is desired, a screen cylinder used for printing with large "flat", ie large evenly inked surfaces, will not be suitable for thinner prints that do not have large "flats".

Solutions for exchanging a screen cylinder have already been proposed. One of these solutions is described in patent CH 686 355 A5. In this patent, the exchange of the screen roll is carried out by means of a carriage comprising screen roll holders. To exchange a screen cylinder, this carriage is introduced laterally between two printing units and the screen cylinder, having previously been released from its bearings, is brought to the level of the screened cylinder supports of the carriage. The carriage can be made in different ways and comprise either a crisscross lifting system or cylinders acting directly on the vertical movement of the screen roll holders. The screen cylinder having been brought to the level of the supports of screen cylinder, these will be moved upwards so as to come into contact with the screen cylinder to support it. The carriage will then be removed laterally from the printing units and brought to the outside of the machine to a processing station where the used screen cylinder can be removed and replaced by a new cylinder. raster. The replacement of the screened cylinder having been carried out, the carriage will be introduced again between the printing units and the new screened cylinder will be set up by repeating, conversely, the same operations as during its extraction from the printing unit. Another solution, substantially identical to the one just described above, is the subject of European patent EP-0.401.636 .

The two solutions that have just been mentioned all have the disadvantage of obliging an operator to get in between the printing units to exchange the screen rolls, which in turn requires particular attention to his safety. . Another disadvantage is the relatively long duration to perform the exchange operation of the screen rolls, which immobilizes all the operation of the machine thereby reducing its productivity.

It is also known from the document US-6,038,972 a robotic apparatus for a printing press provided with a pair of cylinders. The apparatus includes hoisting assemblies and means for moving the hoist assemblies in a first horizontal direction. Each of these lifting assemblies includes a frame and a pickup truck mounted on the frame so as to move vertically. Each of these collection carriages comprises a pair of lifting devices that can be deployed and retracted to handle the cylinders, means for raising and lowering the pickup truck to the frame.

The object of the present invention is to eliminate the aforementioned drawbacks by proposing a method and a device for exchanging the cylinders of printing units of a printing machine in which the safety of the operator is ensured in the most perfect manner possible while minimizing the time required for the exchange operation of the screen rolls.

1. a) pour le chargement des cylindres tramés dans une station de stockage, dans des stations de réserve et dans une position de travail dans les groupes imprimeurs, à :
   • amener premièrement, à l'aide d'un chariot de transport, un premier cylindre tramé dans une station de chargement située à l'entrée d'un margeur ;
   • amener, à l'aide d'un robot, le cylindre tramé, pris de la station de chargement, soit dans la station de stockage située dans la partie inférieure du margeur, soit dans l'une des stations de réserve situées dans l'un des groupes imprimeurs, soit dans une position de déchargement de l'un des groupes imprimeurs ;
   • amener ensuite à l'aide du chariot de transport, préalablement rechargé, un second cylindre tramé dans la station de chargement;
   • amener, à l'aide du robot, le second cylindre tramé, pris de la station de chargement, soit dans la station de stockage située dans la partie inférieure du margeur, soit dans l'une des stations de réserve situées dans l'un des groupes imprimeurs;
   • amener ensuite à l'aide du chariot de transport, préalablement rechargé, un énième cylindre tramé dans la station de chargement;
   • introduire, à l'aide du robot, l'énième cylindre tramé, pris de la station de chargement, soit dans la station de stockage située dans la partie inférieure du margeur, soit dans l'une des stations de réserve situées dans l'un des groupes imprimeurs;
   • introduire, à l'aide du robot, l'un des cylindres tramés pris, soit du chariot de transport, préalablement rechargé, soit de la station de stockage ou soit de l'une des stations de réserve situées dans l'un des groupes imprimeurs, sur un dispositif de transport qui l'amènera dans sa position de travail, dans son groupe imprimeur respectif;
   • positionner et fixer le cylindre tramé dans sa position de travail dans son groupe imprimeur respectif;
2. b) pour l'échange d'un cylindre tramé dans un des groupes imprimeurs, à :
   • libérer le cylindre tramé à échanger de sa position de travail;
   • amener, à l'aide du dispositif de transport, le cylindre tramé à échanger, dans une position de déchargement;
   • amener, à l'aide du robot, le cylindre tramé à échanger, de la position de déchargement, soit à un emplacement libre de la station de réserve du groupe imprimeur concerné, soit l'amener, toujours à l'aide du robot, à un emplacement libre de la station de stockage, soit l'amener, toujours à l'aide du robot sur le chariot de transport préalablement déchargé;
   • prendre, à l'aide du robot, le cylindre tramé de remplacement, soit dans la station de réserve du groupe imprimeur concerné, soit dans la station de stockage, soit sur le chariot de transport;
   • amener, à l'aide du robot, le cylindre tramé de remplacement sur le dispositif de transport qui l'amènera dans sa position de travail et fixer le cylindre tramé de remplacement dans sa position de travail.

For this purpose, the method according to the invention comprises the following steps:

1. a) for the loading of the screen rolls in a storage station, in reserve stations and in a working position in the printing units, to:
   • firstly, using a transport carriage, a first screen cylinder in a loading station located at the entrance of a feeder;
   • bring, by means of a robot, the screened cylinder, taken from the loading station, either into the storage station located in the lower part of the feeder, or into one of the reserve stations located in one of the printer groups, either in an unloading position of one of the printing units;
   • then bring with the transport carriage, previously reloaded, a second screen cylinder in the loading station;
   • bring, using the robot, the second screened cylinder, taken from the loading station, either in the storage station located in the lower part of the feeder, or in one of the reserve stations located in one of the printing groups;
   • then bring with the transport carriage, previously reloaded, an umpteenth roll halftone in the loading station;
   • introduce, using the robot, the umpteenth screened cylinder, taken from the loading station, either in the storage station located in the lower part of the feeder, or in one of the reserve stations located in one of the printing groups;
   • introduce, using the robot, one of the raster cylinders taken, either of the transport carriage, previously reloaded, or of the storage station or of one of the reserve stations located in one of the printing units , on a transport device which will bring it to its working position, in its respective printing group;
   • position and fix the screen roll in its working position in its respective printing unit;
2. (b) for the exchange of a screened cylinder in one of the printing units, to:
   • release the screened cylinder to exchange from its working position;
   • bringing, using the transport device, the screen cylinder to be exchanged, in an unloading position;
   • bring, using the robot, the screen cylinder to be exchanged, from the unloading position, either to a free location of the reserve station of the printing unit concerned, or to bring it, still using the robot, to a free location of the storage station, either bring it, always using the robot on the transport carriage previously unloaded;
   • using the robot, take the replacement screen roll, either in the spare station of the printing unit concerned, in the storage station or on the transport carriage;
   • with the aid of the robot, bring the replacement halftone roll to the transport device which will bring it into its working position and fix the replacement halftone roll in its working position.

The device for loading and exchanging the cylinders of printing units of a printing machine, for the implementation of the method according to claim 1, comprises a loading station, comprising a transport trolley for screened cylinders, followed by a halftone storage station, reserve stations arranged in each printing unit, means for transporting the screen rolls, either from the loading station or from the storage station to a waiting position located in the station one of the printing units, said means for transporting the screen rolls being arranged so as to be able to take a screen cylinder either from a reserve position, or from the storage station or from the loading station for the bring to its working position, said means for transporting the screened cylinders also being arranged so as to be able to remove a screened cylinder from its positi it works to bring it indifferently either in a reserve position, or in the storage station or in the loading station and in that it comprises means for controlling said means for transporting the screened cylinders.

According to an advantageous embodiment, the means for transporting the screen rolls consist of a transport device working jointly with a robot.

According to another embodiment, the robot is arranged to be able to move on rails arranged in parallel between lower parts of the printing units, one of these rails comprising a rack in which a pinion of a gear box engages. gears coupled to a geared motor.

According to another advantageous configuration, the robot comprises a lifting device constituted by levers "X" integral with a base frame, said levers supporting a sole provided with support members for the screened cylinders.

• Les figures 1 à 19 illustrent schématiquement les différentes étapes d'un procédé pour échanger les cylindres tramés d'une machine d'impression flexographique (Pour des raisons de clarté, les signes de référence identiques à ceux de la figure 1 n'ont pas été indiqués sur les figures 2 à 19).
• La figure 20 est une vue en perspective de la partie inférieure d'une machine d'impression flexographique.
• La figure 21 est une vue en perspective d'un organe de chargement et de déchargement des cylindres tramés et
• La figure 22 est une vue en perspective d'un chariot de transport de cylindres tramés.

The invention will be better understood with the aid of the description which follows and which represents an exemplary execution, without limitation, illustrated by means of the appended drawings in which:

• The Figures 1 to 19 schematically illustrate the different steps of a process for exchanging the screen rolls of a flexographic printing machine (For the sake of clarity, the reference signs identical to those of the figure 1 have not been indicated on the Figures 2 to 19 ).
• The figure 20 is a perspective view of the lower part of a flexographic printing machine.
• The figure 21 is a perspective view of a device for loading and unloading the screened cylinders and
• The figure 22 is a perspective view of a carriage transporting raster cylinders.

The figure 1 schematically represents a flexographic printing machine comprising a margin station 1 followed by printing stations or printing groups 2, 3, 4, 5. The printing station 5 is followed by a receiving station 6. The sheets to be printed, not shown, are conveyed through these different stations by means of suction conveyors 7. Each printing unit 2 to 5 comprises a printing cylinder 8, a pressing roll 9 and a screen roll or "anilox" 10. Each printing unit 2 to 5 also has a spare station 11 for screen rolls 17. Each of these printing units 2 to 5 is also equipped with a transport device 13 for the screen rolls 10 in function in its respective printing unit. This transport device 13, of well-known construction, can be associated with a device for engaging and disengaging the bearings of the screen rolls 10, a device which is also well known and therefore not shown in this figure. A storage station 14 is also arranged in the lower part of the margin station 1. In the present embodiment, this storage station 14 has slots for four screened cylinders 17. It is obvious that this number is not limiting. and that a smaller or larger number of slots for the screen rolls in the storage station 14 could be provided. It is also intended to precede the flexographic printing machine with a feed station 16 This feed station 16 is equipped with a transport trolley 18 which can be inserted or removed manually or automatically from this feed station 16. The flexographic printing machine shown in this figure also comprises a robot 19 , represented here in its rest position 19a, provided for the exchange of the different screen rolls 10 of the printing units 2 to 5. In this In the figure, the flexographic printing machine is shown in operation, ie all the screen rolls 10 are in operational contact with their respective printing rollers 8.

The figure 2 represents the flexographic printing machine of the figure 1 in the exchange phase of the screen roll 10 of the printing unit 2. This exchange of the screen roll 10 is required during a change of work requiring the use of a screen cylinder 17 having a configuration of its cells more adequate than the configuration cells of the screened cylinder 10 to perform the new work. As represented by the figure 2 , the screen roll 10, whose bearings have been previously released from their housings in the side frames of the printing unit 2, either manually or automatically with the aid of a known device, for example a device for releasing the bearings by unlocking and pivoting, is removed from its working position 10a by the transport device 13, this into an unloading position 10b.

The figure 3 illustrates one of the following steps of the exchange of the screen roll 10, in particular the step in which the robot 19 begins to move towards the printing unit 2, in the direction indicated by the arrow 20.

The figure 4 shows the robot 19 which has moved to occupy the position 19b in the printer group 2.

The figure 5 represents the robot 19 in the position 19b after its lifting device 21 has been actuated so that its support member 23 of the screen roll 10 comes to be placed under the lower level of the screen cylinder 10. Then, as shown on the figure 6 , the robot 19 is moved to a position 19c, in the direction indicated by the arrow 22. Its lifting device 21 is again actuated so that the support member 23 is brought into contact with the screen roll 10. The next step is, as represented by figure 7 , to move the robot 19 loaded with the screen roll 10, in the direction indicated by the arrow 24, into the position 19b that it previously occupied (see also FIGS. figures 4 and 5 ). Still in this position 19b, the lifting device 21, supporting the screen roll 10, is then lowered as shown in FIG. figure 8 .

The figure 9 represents the robot 19 in the following sequence, that is to say in the position 19d, during which it has been moved, still with its lifting device 21 in the lowered position, in the printing unit 2. In this position 19d, the robot 19 will have brought the screen roll 10 vertically to a screened cylinder storage position 25 located in the reserve station 11. The lifting device 21 of the robot 19 will now be controlled so that it is moved vertically towards the storage position 25 in which the screen roll 10 will be deposited on lateral supports, not shown here, the reserve station 11. This provision is represented by the figure 10 .

As shown on the figure 11 , the robot 19 will then be displaced, in the direction represented by the arrow 26 to a position 19e in which the support member 23 of the lifting device 21 will be vertical to the storage location of a new screen cylinder 17 intended to replace the screen cylinder 10 which has been removed from its working position 10a. Still in the 19th position, the lifting device 21 will be controlled so that it is moved vertically towards the screen cylinder 17 in its storage position 27 in the reserve station 11, until the support member 23 comes into contact with the screen roll 17, as represented by the figure 12 . At this moment, the lifting device 21 supporting the screen roll 17 will be lowered (see FIG. figure 13 ) and the robot 19 will be moved in the direction indicated by the arrow 28 (see figure 14 ) to the position 19b that it previously occupied during the exchange operation of the screen cylinder 10 (see also figures 4 , 5 and 8 ). The lifting device 21 of the robot 19 will then be actuated vertically so as to bring the screen cylinder 17 in the vicinity of the transport device 13, as shown in FIG. figure 15 .

The figure 16 shows that the robot 19 will then be moved again, in the direction indicated by the arrow 29, in the position 19c which is identical to the position it occupied in the description of the figure 6 . The screen cylinder 17 will then be deposited in position 17b on the input of the transport device 13. Referring now to the figure 17 , the robot 19 will be moved again, in the direction indicated by the arrow 30, to the position 19b (see also the figures 4 , 5 , 7 , 8 , 14 and 15 ) then pulled down to occupy the position he occupied on the figures 8 and 14 . The robot 19 can then be finally moved, in the direction indicated by the arrow 31, to its rest position 19a. We have just described the replacement of the screen roll 10 by a new screen roll 17 in the printing unit 2. In this operation, the new screen roll 17 has been taken from the reserve station 11 of this printing unit 2. However, it would be quite conceivable, that according to the necessities inherent to a given work, to take a new screen cylinder of any spare station 11 of the other printer groups 3 to 5 or of the storage station 14 located under the margin station 1 or even of the transport carriage 18 located in the feed station 16, while bringing the robot 19 in a position 19f, as shown in broken lines on the figure 19 , so that it can come to take another screen cylinder 17. It would also be possible to imagine to equip all the reserve stations 11 of two screened cylinders 17 and to leave free a slot for screen cylinder either in the storage station 14 located under the margin station 1, or on the transport carriage 18 placed in the feed station 16. In the event that we have just mentioned, it is obvious that the control of the robot 19 should correspond to the choice of one or the other of the solutions adopted for the exchange of the screen rolls. In the example which we have just described, that is to say the replacement of the screen roll 10 of the printing unit 2 by a screened cylinder 17 taken from the reserve station 11 of this printing unit, this replacement can be carried out "in time masked "ie without the flexographic printing machine is stopped. In this case, it is possible to perform a job requiring only the use of printer groups 3 to 5.

An exemplary embodiment of a device for implementing the method will now be described with reference to the Figures 20 to 22 .

The figure 20 is a perspective view of the lower portion 32 of a flexographic printing machine having five printing units 2, 3, 4, 5 and 33 preceded by a feeder 1. Each printer group 2, 3, 4, 5 and 33 is formed of two side frames of which only the lower portions 34 have been shown in this figure. The feeder 1 is also formed of two lateral frames of which only the lower parts 35, constituting the storage station 14, have been shown. Each lower portion 34, respectively 35 is equipped with support members 36 for receiving the ends of the screen rolls (not shown in this figure). In the example chosen, the lower portions 34 each comprise two support members 36 while the lower parts 35 of the storage station 14 have four. The lower parts 34, 35 are mounted on an alignment rail 37, respectively 38. The device further comprises two tracks 39 and 40, one of which, the race 40 is provided with a rack 41. These two tracks 39 and 40 are intended to serve as a guide for the robot 19 shown here in position in the group The transport carriage 18, which is not shown in the figure, will be placed in the zone 42 located just before the storage station 14 located at the lower part of the feeder 1.

The figure 21 is a perspective view of a device for loading and unloading the screen rolls 17, defined in this description, as the robot 19. This robot 19 is constituted by a base frame 43. having at its front and rear parts a safety device 44. The base frame 43 is arranged to support the lifting device 21 constituted by an elevator formed of "X" levers 45 and 46 supporting a soleplate 47 on which is fixed the support member 23 for the screened cylinders. This support member 23 here consists of two V-shaped pieces 48 and 49. The elevator of the lifting device 21 is controlled by means of a motor 50 acting on a control screw 51 engaging in a nut arranged in the crossbar 52 connecting the lower ends of the levers 46. The base frame 43 is further equipped with a gear motor 53 coupled to a gearbox 54, one of the gears (not shown) meshes with the rack 41 of the road. bearing 40 of the figure 20 . The control of the motor 50 of the elevator of the lifting device 21 as well as the control of the gear motor 53 intended to ensure the movement of the robot 19 are carried out by means of a computer program whose program steps are defined in function. different movements that have been mentioned in relation to the description of the Figures 1 to 19 .

The figure 22 is a perspective view of a transport carriage 18 for a screen cylinder 17. This transport carriage 18 consists of a frame 54 equipped with swivel castors 55 and two centering discs and guide 56 to allow positioning the transport carriage 18 in the insertion station 16 on a well-known manufacturing slide (not shown) and comprising, for example, two guide rails for receiving the two centering and guiding disks 56.

A transport carriage 18 made in this manner will allow the operator to move the screen roll 17, carried by the transport carriage, to a work station, located outside the machine, in which different operations, for example example of the washing operations, may be performed.

Claims (5)

1. Method for loading and exchanging the cylinders of the printing units (2 to 5) of a printing machine, characterised in that it comprises the following steps:

   a) for the loading of the screened cylinders in a storage station (14), in reserve stations (11) and in a working position (10a) in the printing units (2 to 5):

   - to bring firstly, by means of a handling trolley (18), a first screened cylinder (17) into a loading station (16) located at the entry of a feeder (1);

   - to bring, by means of a robot (19), the screened cylinder (17), taken from the loading station (16), either into the storage station (14) located in the lower part of the feeder (1) or into one of the reserve stations (11) located in one of the printing units (2 to 5) or into an unloading position (10b) of one of the printing units;

   - to bring then by means of the handling trolley (18), previously reloaded, a second screened cylinder (17) into the loading station (16);

   - to bring, by means of the robot (19), the second screened cylinder (17), taken from the loading station (16), either into the storage station (14) located in the lower part of the feeder (1) or into one of the reserve stations (11) located in one of the printing units (2 to 5);

   - to bring then by means of the handling trolley (18), previously reloaded, an umpteenth screened cylinder (17) into the loading station (16);

   - to introduce, by means of the robot (19), the umpteenth screened cylinder (17), taken from the loading station (16), either into the storage station (14) located in the lower part of the feeder (1) or into one of the reserve stations (11) located in one of the printing units (2 to 5);

   - to introduce, by means of the robot (19), one of the screened cylinders (17) taken either from the handling trolley (18), previously reloaded or from the storage station (14) or from one of the reserve stations (11) located in one of the printing units (2 to 5), on a transfer device (13) which will bring it into its working position (10a), in its respective printing unit (2 to 5);

   - to position and to attach the screened cylinder (17) in its working position (10a) in its respective printing unit (2 to 5);

   b) for the replacement of a screened cylinder (10) of one of the printing units (2 to 5):

   - to release the screened cylinder (10) to be replaced, from its working position (10a);

   - to bring, by means of the transfer device (13), the screened cylinder (10) to be replaced, into an unloading position (10b);

   - to bring, by means of the robot (19), the screened cylinder (10) to be replaced, from the unloading position (10b), either to a free location of the reserve station (11) of the printing unit (2 to 5) in reference or to bring it, always by means of the robot (19), to a free location of the storage station (14) or to bring it, always by means of the robot (19) onto the handling trolley (18) previously unloaded;

   - to take, by means of the robot (19), the screened cylinder (17) of replacement, either in the reserve station (11) of the printing unit (2 to 5) in reference or in the storage station (14) or on the handling trolley (18);

   - to bring, by means of the robot (19), the screened cylinder (17) of replacement onto the transfer device (13) which will bring it into its working position (10a) and to attach the screened cylinder (17) of replacement in its working position (10a).
2. Device for loading and exchanging the cylinders of the printing units (2 to 5) of a printing machine to implement the method according to claim 1, characterised in that it comprises a loading station (16), including a handling trolley (18) for screened cylinders (17), followed by a storage station (14) for screened cylinders (17), reserve stations (11) arranged in each printing unit (2 to 5), means for transferring the screened cylinders (17), either from the loading station (16) or from the storage station (14) to a waiting position located in the reserve station (11) of one of the printing units (2 to 5), said means for transferring the screened cylinders (17) being arranged so as to be able to take a screened cylinder (17) either from a reserve position (11) or from the storage station (14) or the loading station (16) to bring it into its working position (10a), said means for transferring the screened cylinders (17) being also arranged so as to be able to withdraw a screened cylinder (17) from its working position (10a) to bring it indifferently either into a reserve position (11) or into the storage station (14) or into the loading station (16), and that it comprises means for controlling said means for transferring the screened cylinders (17).
3. Device according to claim 2, characterised in that the means for transferring the screened cylinders (17) consist of a transfer device (13) working together with a robot (19).
4. Device according to claim 3, characterised in that the robot (19) is arranged so as to be movable on rails (39, 40) placed parallel between lower portions (34) of the printing units (2 to 5), one of these rails (40) including a rack (41) in which engages a pinion of a gear box (54) coupled with a gear motor (53).
5. Device according to claim 3, characterised in that the robot (19) comprises a lifting device (21) consisting of "X" levers (45, 46) joined to a base frame (43), said levers supporting a bedplate (47) provided with support members (23) for the screened cylinders (17).

Images