EP0933206A1 - Methods and devices for automatically feeding and/or removing printing plates to/from a plate cylinder of a printing machine - Google Patents

Abstract

The printing plate (1) which is to be supplied is positioned when ready with its leading edge on the plate cylinder (2) so that the leading edge is taken up by the leading edge clamping device (5) through a reverse rotation (7) of the plate cylinder (2). The leading edge clamping device is then closed. Independent claim describes device for implementing the method having an intake chute (9) for inserting a printing plate and positionable on the plate cylinder so that the insert plate can be inserted by its leading edge into the clamping device as the plate cylinder turns back.

Description

The invention relates to a method for automatically feeding a printing plate to the plate cylinder of a printing press, the printing plate leading edge in a Front edge clamping device is inserted and clamped and the plate cylinder the printing plate is wound up by forward rotation.

The invention further relates to a method for automatically removing a Printing plate from the plate cylinder of a printing press, one Trailing edge tensioning device opens and the plate cylinder through a Reverse rotation unwinds the pressure plate and in the direction of one Removal position pushes.

The invention also relates to a device for carrying out the former Process with a feed shaft for inserting a printing plate and a Plate cylinder with an automatically operated front edge clamping device.

Finally, the invention relates to a further device for performing the second mentioned method with a pull-out shaft and a plate cylinder an automatically operated leading and trailing edge tensioning device and a control system for removing a printing plate, the trailing edge tensioning device opens and the printing plate trailing edge by turning the plate cylinder in reverse pushes the pull-out shaft.

Such methods and devices are both from DE 41 30 359 A1 and the 195 08 844 A1 known. For the objects of both publications, the Feeding as suggested for removing the printing plate transport devices, which feed the printing plates into the leading edge clamping device or when removing the printing plates from the leading edge clamping device transport out. Lifting devices are proposed as transport devices are arranged on slidable supports and the with the help of drives Transport printing plates. The disadvantage of these transport devices is that that they are complex, expensive and prone to failure.

The invention is therefore based on the object, methods and devices to make available at the outset, by means of which the feeding and / or Removal of the printing plates in a simple manner without additional transport devices is possible.

With regard to the method for feeding printing plates, the task solved according to the invention in that the pressure plate to be fed at their Provision is positioned with its front edge on the plate cylinder so that the Leading edge by a reverse rotation of the plate cylinder from the Leading edge tensioning device is added and that then the Front edge tensioning device closes.

As a device for performing this method it is provided that the The feed slot can be positioned on the plate cylinder in such a way that the inserted one Printing plate by turning the plate cylinder backwards with its front edge into the Front edge tensioning device can be inserted, and that such a control it is intended that they reverse the rotation of the plate cylinder after insertion of the Leading edge in the leading edge tensioner stops Front edge tensioner closes and then a forward rotation of the Plate cylinder for winding the printing plate causes.

With regard to the removal of printing plates, the object is achieved according to the invention solved a method, which is characterized in that the plate cylinder Push the pressure plate backwards so far towards the removal position pushes and the removal position to the plate cylinder in such a position and Alignment is that the front edge of the plate is when opening the Leading edge tensioning device and a forward rotation of the plate cylinder of removed and moved to the removal position.

The device for performing the method provides that the pull-out shaft Holding means having a backward movement of the pressure plate against the Prevent sliding direction, and that the controller is designed such that it Reverse rotation of the plate cylinder continues until the opening of the Leading edge tensioning device and a forward rotation of the plate cylinder as well due to the location and arrangement of the pull-out shaft in the direction of The plate cylinder has the end of the pull-out shaft on the front edge of the printing plate that end.

The methods and devices according to the invention have the advantage that they do not need additional resources to feed and remove the printing plates capture and transport. This function is fully taken over by the Plate cylinder. When feeding the printing plates, the plate cylinder detects them in the Deployment position by the leading edge tensioning device by a Reverse rotation of the plate cylinder grips the front edge of the pressure plate. With respect to the removal of the printing plates, the plate cylinder pushes the printing plate in the removal position and finally gives the leading edge of the printing plate freely that there is a brief moment at the backward rotation for unwinding the printing plate Forward rotation connects through which the leading edge tensioning device Front edge of the pressure plate releases and this is due to its internal stress and / or deposits its weight in the removal position.

After grasping or completely releasing the printing plates According to the invention is carried out by the plate cylinder itself, the Need to use any device equipped with drives To provide transport facilities. They are also not similar to transport trolleys Devices with suction cups or similar gripping elements are required. Thereby the procedure for automatic plate changing is simplified, and the corresponding devices are less complicated and therefore less prone to failure and above all, much cheaper to manufacture. In addition, the Device due to the simpler construction, much less space. The device can thus be made flatter, which in the narrow spaces between the printing units of multicolour printing machines is of great advantage.

The following are numerous training opportunities and configurations described, wherein also an advantageous embodiment, the assembly of the two devices to a single change system.

An embodiment of the device for the automatic feeding of printing plates provides that the feed chute is in its feed position with its lower one End in a tangential plane to the circle of movement of the leading edge tensioning device is located, which extends obliquely upwards from the clamping area. This is it is possible to insert a new pressure plate into the top of the feed slot and it using their gravity to their end position for feeding to Let the plate cylinder slide into the feed slot.

Another embodiment provides that the feed chute holding means for holding an inserted pressure plate. This holding means creates a counterforce generated so that the pressure plate when inserted into the The position of the leading edge tensioning device has not been changed. Can be used as a holding device at least one, but preferably two spaced-apart suction cups are provided be retractable from the insertion path for the pressure plate and for holding the Pressure plate can be moved into the feed shaft. With such suction cups the pressure plate is positioned securely. Of course it would also be possible to provide clamping levers as holding means, since they do not require a drive, but clamp automatically if due to the insertion process in the Front edge tensioning device counteracts a slight movement of the pressure plate the direction of insertion.

In order to achieve an exact positioning of the printing plates, further training is envisaged before that the feed chute has positioning means for the printing plates.

The positioning means are advantageously two positioning pins, which is intended for engagement in two spaced-apart recesses of a pressure plate are. Most printing plates have such recesses, since this is the Precise registration in the front edge clamping device of the plate cylinder serve, which also has such positioning pins for this purpose. To the It is planned to release the printing plate in the feeder shaft after this positioning. that the positioning pins can be moved away from their engaged position.

The interaction of the movable positioning pins with is particularly advantageous Holding means: First the pressure plate is inserted using the positioning pins precisely aligned, then held by the holding means and then the positioning pins moved away. As a result, the pressure plate is in an exact position in which it is from the leading edge tensioning device with insertion of the recesses of the pressure plate included in the register bolts of the leading edge tensioning device and can be clamped in register.

The device is advantageously designed in such a way that the feed shaft of the retracted position is movable into a rest position. Such a shipment in the rest position should take place because the intake shaft with its lower End must be very close to the plate cylinder and in the Reaches into the printing unit. However, during printing, it is desirable that the Feed slot is removed from the plate cylinder and positioned in front of the printing unit. This is achieved, for example, in that the feed chute consists of a essentially vertical upper area and a lower area, which for Insertion of the pressure plate from the substantially vertical position to Plate cylinder is pivotable. This swiveling movement causes the lower part of the feed slot in the position in which the pressure plate for the Detection is kept ready by the leading edge clamping device. After moving in the pressure plate, this lower part of the feeder shaft can be removed from the Printing unit can be swung out. In this position it is also easier to create a new one Push the pressure plate into the feed slot because the pressure plate is straight can be pushed in. The pivoting of the lower part of the Feed slot also has the advantage that the upper area is always parallel to Printing unit runs and therefore never in the aisle between the printing units protrudes.

In order to rule out any damage to the printing surface suggested that the feed slot at its lower limit over its entire width distributed rollers for guiding the printing plates. From the same reason it is proposed that the feed shaft to guide the Pressure plate with beads, which are coated with lubricants, which is extend along the path of the pressure plates. The lubricants can be Trade sliding varnish, sliding bands or a corresponding profile. However, it can also be provided that the feed slot roller guides on its entire surface for guiding the pressure plates.

Another expedient embodiment provides that the feed shaft with Brake devices is equipped, the case of an inserted pressure plate in the Brake the feeder shaft at least so much that damage is impossible is. The braking devices can be brushes that are in the upper one Area of the feed shaft are arranged distributed over the width. It's going on this Way excluded that the pressure plates fall down in the feeder shaft and be damaged by it. The brushes are set so that the Pressure plates in the feed chute, guided by hand, light and slow slide in.

If printing plates are no longer new but have already been printed with them, then there is the problem is that they have a bend. Such a bend could there is a risk that they will move over the positioning pins and thereby no longer positioned exactly in register and passed on to the plate cylinder. To prevent this, it is proposed that in the area of the positioning pins Resilient guide elements are arranged that a pressure plate in the effective area of the positioning pins. It can be leaf springs that in Insert direction and the pressure plate with a rounded front end press against the sliding surface.

As an embodiment for the device for removing printing plates proposed that a collecting plate is arranged at the end of the pull-out shaft and that in the position for the removal of a printing plate, the collecting plate in a plane that is below a tangent plane to the plate cylinder extends, starting from the unclamping positions of the front and the Trailing edge tensioning device runs obliquely upwards. This arrangement has the Advantage that the pull-out shaft runs essentially parallel to the feed shaft and thereby a compact device for feeding and removing Printing plates is possible. Another advantage is that after opening the Leading edge clamping device and the release of the pressure plate leading edge by the Counter-movement of the plate cylinder is not only due to the pressure plate Elasticity but also by gravity on the collecting plate. Thereby is guaranteed to move away from the plate cylinder while doing so Takes up position.

It is proposed that the pull-out shaft move from the pull-out position into a Rest position is movable. Such an embodiment is from the above for Feeder shaft useful reasons mentioned. The pull-out shaft can be used be designed such that it consists of a substantially vertical upper region and a lower area, which is used to remove a printing plate from an im essential vertical position to the plate cylinder is pivotable. This Swivel leads in cooperation with the holding elements that the Pressure plate is pushed further up and can be removed even more conveniently. There by pivoting the lower area towards the upper area Opening gap occurs, which can hit a pressure plate, it is proposed that between the lower and upper areas guide elements for guiding the pressure plate are arranged in the transition area. It is expedient to Leaf springs attached to one area and the other in such a way protrude that they lie there smoothly on the walls.

With regard to the holding means, it is proposed that it be at least one Clamping lever acts against the movement of the pressure plate Insertion direction goes into its clamping position. The clamping lever is when inserting the pressure plate is loose and is entrained by a countermovement such that it wedges the pressure plate on the sliding surface. This function can be due to the Gravity or spring support.

A further development provides that a sensor is arranged on the collecting plate, which detects whether, after opening the rear edge tensioning device, the storage of the Pressure plate trailing edge takes place, the signal to interrupt the process and is given to the control system for error display. It will malfunction avoided if the trailing edge tensioning device is the trailing edge of the pressure plate does not release what, for example, by changing their voltage due to a manual intervention can occur.

It is also proposed that a sensor in the upper area of the pull-out shaft is arranged, which detects whether a printing plate the predetermined removal position has reached. This sensor can either serve that the signal for Interruption of the process and to the controller for error indication, or it can serve to remove a printing plate from the plate cylinder prevent as long as there is still a pressure plate in the pull-out shaft. For the the latter function is intended so that the sensor before each change from the Control is queried whether there is still a pressure plate in the pull-out shaft and only after removing the device for a printing plate removal from Plate cylinder is released.

Damage should also be avoided with printing plates to be removed, since these are often to be used for other prints. It is therefore proposed that the pull-out shaft for guiding the pressure plates with beads that are lubricated are occupied, which extends along the path of the printing plates.

Another possibility is that the pull-out shaft over its sliding surface distributed roller guides for guiding the printing plates.

To do both of the methods mentioned at the beginning with a single device to be able to perform, i.e. to both feed and remove printing plates, it is proposed that the feed shaft and the pull-out shaft become one Exchange system are summarized. With this changing system it is possible Provide all new printing plates while the machine is running and then to initiate the automatic change immediately after the end of a print job. After that, the next print job can begin, using the old printing plates again can be removed while the machine is running.

This changing system is expediently designed such that the Feed slot and the pull-out shaft have upper and lower areas, wherein the latter are pivotable together and by at least one 3-position cylinder in a feed position, a pull-out position and a rest position are spendable. This takes into account the requirements already in the description of the individual devices were mentioned above, and so will achieved the advantages mentioned here. The design can be such that the Swivel joint on the printing unit side between the upper and the lower areas and there is at least one 3-position cylinder on the opposite side.

In this embodiment, in the event of a power failure, the lower areas unintentionally swivel towards the plate cylinder, causing too can lead to a collision. It is therefore proposed that the side of the Change system on which the at least one 3-position cylinder is arranged Holder is located, the pivoting of the lower areas due to a power failure of the 3-position cylinder prevented.

By swiveling the lower areas of the feeder shaft and the The pull-out slot in the retracted position can cause a collision with the Pull-out tray connected to the receiving plate come with the plate cylinder. This is avoided in that the collecting plate by means of a spring-loaded hinge is hinged to the lower area of the pull-out shaft and that a further stop the catch plate in the retracted position to avoid a Collision swings away with the plate cylinder.

In order to be able to work on the printing unit, it is necessary that the Exchange system can be moved away. This is achieved in that the change system by means of two cables on both sides with pulleys and counterweights can be pushed upwards to expose the printing unit. Here are the Counterweights are expediently dimensioned in such a way that the change system by hand is easy to move up and down and stands still in any position due to the friction.

A blanket holder can be arranged at the lower end of the change system, thus with assembly work, for example the insertion of documents on Rubber cylinder the blanket can be held.

An exact position of the changer to the plate cylinder is achieved in that through the joined and jointly pivotable lower areas Support support rollers on the bearer rings of the plate cylinder.

The device according to the invention also expediently works with one Pinch roller together, as already from the devices of the entrance mentioned prior art is known. It is envisaged that the Device according to the invention with a pressure roller for applying a Pressure plate cooperates. In addition, it can be provided that a pressure roller is arranged such that the rear end of a pressure plate after opening the Trailing edge tensioning device also places on the pressure roller and then over the Collecting plate is pushed to the pull-out shaft.

Fig. 1

ein Ausführungsbeispiel einer Vorrichtung zum Zuführen und Entfernen von Druckplatten,

Fig. 2

einen Ausschnitt aus einem weiteren Ausführungsbeispiel bei der Plattenzuführung,

Fig. 3

einen Ausschnitt aus einer Vorrichtung zum Entfernen von Druckplatten in einem Verfahrensschritt, in dem sich die Druckplattenhinterkante ablegt,

Fig. 4

denselben Ausschnitt bei einem späteren Verfahrensschritt,

Fig. 5

eine Einzelheit einer Vorrichtung zum Zuführen von Druckplatten,

Fig. 6

eine Ausführungsform von Gleitflächen,

Fig. 7 und 8

eine Bremsvorrichtung und die Anordnung eines Sensors,

Fig. 9

die Anordnung von Leitelementen,

Fig. 10

Positionierstifte mit federnden Leitelementen,

Fig. 11

ein Halter für Energieausfall eines Stellelements,

Fig. 12

eine Vorrichtung zur Verschiebung des Wechselsystems und

Fig. 13

die Anordnung eines Gummituchhalters.

The invention is explained below with reference to exemplary embodiments and partial views, which are shown in the drawing. Show it

Fig. 1

an embodiment of a device for feeding and removing printing plates,

Fig. 2

a section of a further embodiment of the plate feed,

Fig. 3

a section of a device for removing printing plates in a process step in which the trailing edge of the printing plate is deposited,

Fig. 4

the same section in a later process step,

Fig. 5

a detail of a device for feeding printing plates,

Fig. 6

an embodiment of sliding surfaces,

7 and 8

a braking device and the arrangement of a sensor,

Fig. 9

the arrangement of guide elements,

Fig. 10

Positioning pins with resilient guide elements,

Fig. 11

a holder for power failure of an actuator,

Fig. 12

a device for moving the changing system and

Fig. 13

the arrangement of a blanket holder.

1 shows an exemplary embodiment of the device according to the invention, a device for feeding printing plates 1 'and a device for removing printing plates 1''being combined to form a changing system 28. The device for feeding printing plates consists of a feed chute 9, which consists of an upper, vertical region 12 and a lower region 13. This lower area 13 is also oriented vertically in its rest position, which is shown in dash-dot lines. To supply printing plates, this lower region 13 is pivoted against the plate cylinder, this is the excellent illustration.

A pull-out shaft 18 is arranged parallel to the feed shaft 9 and is also made of an upper region 23 and a pivotable lower region 24. The upper regions 12 and 23 and the lower regions 13, 24 are connected to one another, the lower regions 12 and 23 together around a printing unit side Joint 31 are pivotable. Serves to pivot these lower areas 13 and 24 one, but preferably two 3-position cylinders 29, which the joint 31st are attached opposite.

The exchange system 28 is arranged on the side of a printing unit 3, specifically in such a way that the lower regions 13 and 24 pivot into an opening of the printing unit 3 can and in this way in the drawn change position on the plate cylinder 2nd reach. On the plate cylinder 2 is a pressure roller 38 known type arranged with which the change system 28 can cooperate. Below the Plate cylinder 2 is the rubber cylinder 37 and above the Plate cylinder 2, the inking system not shown.

The function of the printing plate feed is as follows: In the feed shaft 9 is at the top a pressure plate 1 'to be fed in such a way that it is located at the lower end of the Feed slot 9 protrudes a little bit. Then the plate cylinder 2 a reverse rotation 7 until the printing plate leading edge 4 in the Front edge tensioning device 5 engages. Holding means 10, here as a clamping lever 10 '' trained, hold the pressure plate 1 'in the lower region 13 of the feed shaft 9 firm. The front edge clamping device 5 closes and the plate cylinder 2 rotates itself in the forward direction 6 until it has received the pressure plate 1 '. Finally the folded printing plate trailing edge 20 by the pressure roller 38 in the Inserted trailing edge tensioning device 19, this closes and makes one Swivel movement to clamp the printing plate 1 on the plate cylinder 2.

The printing plate removal takes place as follows: The plate cylinder 2 rotates in a position in which the pressure plate trailing edge 20 can be deposited on the pressure roller 38 is. Then the rear edge tensioning device 19 opens and the pressure plate 1 ″ is opened by a reverse rotation 7 of the plate cylinder 2 into the pull-out shaft 18th pushed. Is the pressure plate 1 '' inserted as far as this in the drawing is shown, the plate cylinder 2 stops and the leading edge tensioning device 5 opens. Then the plate cylinder 2 rotates in the forward direction 6, the Printing plate leading edge 4 slides out of the leading edge tensioning device 5 and itself in the lower area 24 of the pull-out shaft 18, possibly also on the Pressure roller 38, sets. Holding means 21, for example designed as a clamping lever, ensure that the pressure plate 1 '' does not slip back and in its removal position 8 remains After that, the pressure plate 1 '' can be pulled out of the pull-out shaft 18 Operator can be removed.

Both the provision of a pressure plate 1 'to be supplied and the removal of the printing plate 1 '' to be removed can be made while the machine is running be, only the automatic change process on the plate cylinder 2 takes place during the Machine downtime between two print jobs. Besides, it is possible that in multi-color printing machines change processes on the individual Printing units take place simultaneously or overlapping in time. The thereby achieved Saving time is the advantage of automatic plate change.

FIG. 2 shows a section of a further exemplary embodiment of a changing system 28 for the printing plate feed. The holding means 10 is designed here as a suction cup 10 'which holds the pressure plate 1' placed in the feed shaft 9, while the front edge tensioning device 5 grips the pressure plate front edge 4 by a reverse rotation 7 of the plate cylinder 2. In this case, recesses on the leading edge 4 of the printing plate are inserted into register bolts 39 of the leading edge clamping device 5 in order to guarantee the register accuracy of the printing plate 1 on the plate cylinder 2. After insertion, the front edge tensioning device 5 closes and the lifting suction device 10 'releases the pressure plate 1'. The further process then takes place as already described for FIG. 1.

In this exemplary embodiment, the lower region 24 of the pull-out shaft 18 a catch plate 22 attached. This appendage is spring loaded Hinge made with stop 30, which ensures that the collecting plate 22 is in its catch position. However, the change system 28 in a position for Plate feed, a further stop 47 ensures that the The catch plate 22 is pivoted away against the force of the spring of the hinge 30 not to collide with the plate cylinder 2. The counterpart of the further attack 47 is not shown. Are the lower areas 13 and 24 back or in the Plate removal position pivoted, the collecting plate 22 takes that in Fig. 3rd drawn position opposite the pull-out shaft 18. Fig. 2 shows how Both the feed shaft 9 and the pull-out shaft 18 are equipped with beads 15 are, which have lubricants on their top. As a result, the printing plates 1 spared, which rest with their pressure surfaces in the two shafts 9 and 18. Furthermore, there is a holding means 21 at the lower end of the pull-out shaft 18 shown, which is designed as a clamping lever.

3 shows a detail from a device for removing printing plates 1. The plate cylinder 2 is in the unclamping position for a printing plate 1, in which the trailing edge tensioning device 19 opens and the printing plate 1 moves from its position shown in broken lines in the direction of arrow 40 and settles on the catch plate 22. The collecting plate 22 is also equipped with the beads 15 described above in order to protect the surface of the pressure plate 1 ″. In the lower area 24 of the pull-out shaft 18, a clamping lever 21 is arranged, which can deflect against the force of a spring 41 into the position shown in broken lines. As a result, the clamping lever 21 dodges when the plate cylinder 2 pushes the pressure plate 1 ″ into its removal position 8 by reverse rotation 7.

4 shows the same section in a later method step. The pressure plate 1 ″ has now been moved into its removal position 8, and only the front edge 4 of the pressure plate has to be released by the front edge tensioning device 5. For this purpose, the front edge tensioning device 5 opens, and the plate cylinder 2 makes a forward rotation 6, as a result of which the printing plate 1 ″ is deposited on the collecting plate 22 in the direction of arrow 52 from its position shown in broken lines. The spring 41 presses the clamping lever 21 in the direction of the arrow 53 until it assumes the position shown in FIG. 3, as a result of which the pressure plate 1 ″ is held securely in its removal position 8. If the pressure plate 1 ″ is removed by an operator, the clamping lever 21 returns to the position now shown in FIG. 4, and the pressure plate 1 ″ can be easily removed.

Fig. 5 shows a detail of an apparatus for feeding printing plates. The pivotable sliding surface of the lower area 13 of the feed chute 9 is shown. This lower area contains, as holding means 10, the lifting suction devices 10 'already described for FIG. 2. Furthermore, rollers 14 are arranged on the lower boundary of this area, which ensure that there is no damage to a pressure plate 1 'at the edge. In addition, projecting positioning pins 11 are arranged at the lower end and can be moved away by means of a drive 43.

The function is as follows: The pressure plate 1 'to be fed is inserted into the feed shaft 9 used such that the positioning pins 11 in the recesses already mentioned engage on the leading edge 4 of the printing plate. Then the suction lifters 10 'enter Action and hold the pressure plate 1 'in this position. Then the Positioning pins 11 moved away by means of a drive 43, and the plate cylinder 2 grips the pressure plate leading edge 4 with its leading edge tensioning device 5. For this purpose, the plate cylinder 2 makes a reverse rotation 7 Printing plate leading edge 4 inserted into the front edge clamping device 5, so closes it, and the plate cylinder 2 takes the printing plate 1 by a forward rotation 6th on. In this way, the pressure plate 1 'to be fed is registered in the register Positioned feed chute 9 and with this register accuracy from plate cylinder 2 accepted. Inaccuracies in the transfer are avoided.

6 shows an embodiment of sliding surfaces of both the feed shaft 9 and the pull-out shaft 18. These sliding surfaces have beads 15 which are provided with lubricants. In a similar manner, of course, rollers distributed over the sliding surfaces can also be arranged. The guide of the pressure plates 1 takes place in that these sliding surfaces each have a U-shaped configuration 44 on their sides, which hold and guide the pressure plates 1 at their edges. In this way, a printing plate 1 is protected from damage during its transport.

7 and 8 show a braking device 16 and the arrangement of a sensor 27, FIG. 8 showing a view in the direction of the arrow 46 drawn in FIG. 7. The protection 45 surrounding the changing system 28 is visible. The braking device 16 is arranged at the upper end of the feed chute 9. It is designed here as brushes arranged along the insertion opening. The braking device 16 prevents a pressure plate 1 ″ falling into the feed shaft 9 due to its own weight and being damaged in the process. The brushes are designed and dimensioned in such a way that a pressure plate 1 ″ can be easily inserted, but prevents falling.

At the upper end of the pull-out shaft 18, a sensor 27 is arranged, which the Presence of a printing plate 1 detected. The sensor 27 is used to monitor the Plate removal process by giving a signal when there is a Pressure plate 1 'is in its removal position 8. In this way it is detected whether the removal of the printing plate 1 '' from the plate cylinder 2 is completed.

Furthermore, however, the sensor 27 can also serve to detect the presence of one of a Operator from the pull-out shaft 18 of the printing plate 1 ″ in front of each to query further printing plate changes. If the old pressure plate 1 '' was not removed, so the operator receives a signal that they only remove this pressure plate 1 '' must before another change process is possible.

9 shows the arrangement of guide elements 25 between the upper region 23 and the lower region 24 of the pull-out shaft 18. In the illustration, the pull-in shaft 9 was not drawn, but only the swivel frame 48 on which the lower regions 13 and 24 of the pull-in shaft 9 and the pull-out shaft 18 are mounted. These two areas are pivoted about the joint 31, for which the 3-position cylinder 29 is used. The result of this pivoting is that an opening gap is created in the pull-out shaft 18 between the upper region 23 and the lower region 24, which opening gap 20 cannot be passed through easily. For this reason, guide elements 25 are attached to the transition. These guide elements 25 are fastened to the lower region 24 and are designed to be resilient in such a way that they rest on the walls of the upper region 23 and in this way forward the pressure plate 1 ″.

Fig. 10 shows positioning pins 11 with resilient guide elements 17. If a pressure plate is inserted into the feed shaft 9, it must be guaranteed that the pressure plate leading edge 4 engages with its recesses in the positioning pins 11 in order to ensure precise positioning. However, if printing plates are used that have already been used for printing, they are no longer flat but have a bend. As a result, there is a risk that the front edge 4 of such pressure plates 1 will no longer engage with its recesses in the positioning pins 11, since the bend keeps the pressure plate front edge 4 away from the sliding surface. Therefore resilient guide elements 17 are arranged, which are designed here as leaf springs and point in the direction of insertion of the pressure plate 1, such that they guide a pressure plate front edge in the direction of the sliding surface and press against it, so that the pressure plate front edge 4 safely reaches the positioning pins 11.

11 shows a holder 32 for power failure. In one embodiment, in which the lower regions 13 and 24 of the feed shaft 9 and the pull-out shaft 18 can be pivoted together about a joint 31, the pivot frame 48 tends to pivot out in the direction of the plate cylinder 2 due to its center of gravity. This is not a problem in a normal operating situation , since in the rest position the 3-position cylinder 29 with its piston rod 54 holds the swivel frame 48 in such a way that it maintains the vertical position. However, if there is a power failure, for example the compressed air in a pneumatic cylinder 29, the lower regions 13 and 24 would pivot in the direction of the plate cylinder 2, which could lead to a collision. In order to prevent such a situation, a holder 32 is attached to the piston rod 54 or at a location on the swivel frame 48 and engages with a retaining bolt 50 in a spring clamp 49. This retaining bolt 50 is retracted or extended by the force of the 3-position cylinder 29 during each swiveling operation. However, if the energy of the 3-position cylinder 29 fails in the rest position, the piston rod 54 and thus the swivel frame 48 are held in this rest position.

12 shows a device for displacing the changing system 28. Deflecting rollers 34 are arranged on the printing unit 3 or on separate columns, via which cable pulls 33 run, which are connected on the one hand to the changing system 28 and on the other hand to counterweights 35. The weight of the counterweights 35 is balanced in such a way that it is possible to push the exchange system 28 upwards in order to be able to carry out work on the printing unit 3. With correct balancing, the shifting process takes place with little effort, and the device stops as soon as it is no longer pushed. Additional securing bolts can be used to lock the change system 28 in the respective position.

Fig. 13 shows the arrangement of a blanket holder 36. For work on the blanket cylinder 37, for example for laying on documents, the blanket 51 must be removed and put down. To facilitate such work, a blanket holder 36 is arranged at the lower end of the changing system 28, to which the blanket 51 can be attached until it is reinstalled.

The drawing and the associated description are limited to a few of the possible embodiments. A variety of combinations of the listed Features are conceivable.

Reference list

1

printing plate

1'

pressure plate to be fed

1''

pressure plate to be removed

2nd

Platter cylinder

3rd

Printing unit

4th

Printing plate front edge

5

Leading edge tensioning device

6

Arrow - forward rotation

7

Arrow - reverse rotation

8th

Removal position

9

Feed slot

10th

Holding means

10 '

Suction cups

10 ''

Clamping lever

11

Positioning pins

12th

upper area of the feed chute

13

lower area of the feed chute

14

roll

15

Beads

16

Braking device

17th

springy guide elements

18th

Pull-out shaft

19th

Trailing edge tensioning device

20th

Trailing plate edge

21

Holding means, e.g. Clamping lever

22

Collecting plate

23

upper area of the pull-out shaft

24th

lower area of the pull-out shaft

25th

Guide elements, e.g. Leaf springs

26

Sensor (collecting plate)

27

Sensor (pull-out shaft)

28

Change system

29

3 position cylinder

30th

spring loaded hinge with stop

31

joint

32

Holder for power failure

33

Cables

34

Pulleys

35

Counterweights

36

Blanket holder

37

Rubber cylinder

38

Pressure roller

39

Register bolt of the leading edge tensioning device

40

Arrow: Place the pressure plate on the collecting plate

41

Spring of the clamping lever

42

Arrow: Release of the printing plate leading edge when removing the plate

43

Drive for positioning pins 11

44

U-guide for intake or pull-out chute

45

Protection of the changing system

46

Arrow: view Fig. 8

47

further stop

48

Swing frame

49

Spring clip

50

Retaining bolt

51

Rubber blanket

52

Arrow: Place the rear edge of the printing plate on the collecting plate

53

Arrow: clamp the clamping lever

54

Piston rod of the 3-position cylinder

Claims (39)

Method for automatically feeding a printing plate (1) to the platen cylinder (2) of a printing press (3), the printing plate leading edge (4) being inserted and clamped in a leading edge clamping device (5) and the plate cylinder (2) pressing the printing plate (1) by forward rotation ( 6) coiled,
characterized,
that the pressure plate (1) to be supplied is positioned with its front edge (4) on the plate cylinder (2) in such a way that the front edge (4) is received by the front edge tensioning device (5) by a reverse rotation (7) of the plate cylinder (2) and that then the leading edge tensioning device (5) closes. Device for carrying out a method according to claim 1, with a feed shaft (9) for inserting a pressure plate (1) and a plate cylinder (2) with an automatically operated front edge tensioning device (5),
characterized,
that the feed shaft (9) can be positioned on the plate cylinder (2) in such a way that the inserted pressure plate (1) can be inserted into the front edge clamping device (5) by turning the plate cylinder (2) backwards (7) with its front edge (4), and that a Control designed in such a way that it stops the backward rotation (7) of the plate cylinder (1) after insertion of the front edge into the front edge tensioning device (5), closes the front edge tensioning device (5) and then a forward rotation (6) of the plate cylinder (2) for winding the pressure plate (1). Device according to claim 2,
characterized,
that the feed chute (9) is in its retracted position with its lower end in a tangential plane to the movement circle of the leading edge tensioning device (5), which extends obliquely upwards from the tensioning area. Device according to claim 2 or 3,
characterized,
that the feed shaft (9) has holding means (10, 10 ', 10'') for holding an inserted pressure plate (1). Device according to claim 4,
characterized,
that the holding means (10) is at least one lifting suction device (10 '), which can be withdrawn from the insertion path for the pressure plate (1) and can be moved into the feed shaft (9) to hold the pressure plate (1). Device according to one of claims 2 to 5,
characterized,
that the feed shaft (9) has positioning means for the pressure plates (1). Apparatus according to claim 6,
characterized,
that the positioning means are two positioning pins (11) which are intended for engagement in two spaced-apart recesses in a pressure plate (1) and are arranged at the lower end of the feed chute (9). Device according to claim 7,
characterized,
that the positioning pins (11) can be moved away from their engaged position. Device according to one of claims 2 to 8,
characterized,
that the feed shaft (9) can be moved from the feed position into a rest position. Device according to claim 9,
characterized,
that the feed shaft (9) consists of a substantially vertical upper region (12) and a lower region (13) which can be pivoted from the substantially vertical position to the plate cylinder (2) for the insertion of the pressure plate (1). Device according to one of claims 2 to 10,
characterized,
that the feed shaft (9) has at its lower limit distributed over its entire width rollers (14) for guiding the pressure plates (1). Device according to one of claims 2 to 11,
characterized,
that the feed shaft (9) for guiding the pressure plates (1) is equipped with beads (15), which are coated with lubricants, which extend along the path of the pressure plates (1). Device according to one of claims 2 to 10,
characterized,
that the feed shaft (9) has roller guides for guiding the pressure plates (1) over its entire sliding surface. Device according to one of claims 2 to 13,
characterized,
that the feed shaft (9) is equipped with braking devices (16) which brake a case of a pressure plate (1) in the feed shaft (9) at least so much that damage is excluded. Device according to claim 14,
characterized,
that the braking devices (16) are brushes. Device according to one of claims 2 to 15,
characterized,
that resilient guide elements (17) are arranged in the area of the positioning pins (11) and press a pressure plate (1) into the effective area of the positioning pins (11). Method for automatically removing a printing plate (1) from the plate cylinder (2) of a printing press (3), wherein a trailing edge tensioning device (19) opens and the plate cylinder (2) unwinds the printing plate (1) by a backward rotation (7) and thereby in the direction of one Removal position (8) pushes,
characterized,
that the plate cylinder (2) pushes the pressure plate (1) by the reverse rotation (7) so far in the direction of the removal position (8) and the removal position (8) to the plate cylinder (2) is in such a position and orientation that the plate leading edge (4) when opening the front edge tensioning device (5) and a forward rotation (6) of the plate cylinder (2) away from this and moved into the removal position (8). Apparatus for carrying out a method according to claim 17 with a pull-out shaft (18) and a plate cylinder (2) with an automatically operated front edge (5) and rear edge tensioning device (19) and a control system which, for removing a pressure plate (1), the rear edge tensioning device (19 ) opens and pushes the pressure plate rear edge (20) by turning the plate cylinder (2) backwards (7) into the pull-out shaft (18),
characterized,
that the pull-out shaft (18) has holding means (21) which prevent the backing of the pressure plate (1) against the sliding direction, and that the control is designed such that it continues the backward rotation (7) of the plate cylinder (2) until the opening of the front edge tensioning device (5) and a forward rotation (6) of the plate cylinder (2) and, due to the position and arrangement of the pull-out shaft (18) with one end of the pull-out shaft (18) pointing in the direction of the plate cylinder (2), the pressure plate front edge (20) put on this end. Device according to claim 18,
characterized,
that a catch plate (22) is arranged at the end of the pull-out shaft (18) and that in the position for removing a pressure plate (1 ') the catch plate (22) is in a plane which is below a tangential plane to the plate cylinder (2) extends, which, starting from the unclamping positions of the front (5) and rear edge clamping device (19), runs obliquely upwards. Device according to claim 18 or 19,
characterized,
that the pull-out shaft (18) can be moved from the pull-out position into a rest position. Device according to one of claims 18 to 20,
characterized,
that the pull-out shaft (18) consists of a substantially vertical upper region (23) and a lower region (12) which can be pivoted towards the plate cylinder (2) to remove a printing plate (1) from a substantially vertical position. Device according to claim 21,
characterized,
that between the upper and lower areas (23, 24) guide elements (25) for guiding the pressure plate (1) are arranged in the transition area. Device according to one of claims 18 to 22,
characterized,
that the holding means (10) is at least one clamping lever (10 '') which, when the pressure plate (1 '') moves, moves into its clamping position counter to the direction of insertion. Device according to one of claims 18 to 23,
characterized,
that a sensor (26) is arranged on the collecting plate (22), which detects whether, after opening the rear edge tensioning device (19), the printing plate rear edge (20) is deposited, the signal being given to the control system to interrupt the process and to indicate an error becomes. Device according to one of claims 18 to 24,
characterized,
that a sensor (27) is arranged in the upper region (23) of the intake shaft (18), which detects whether a pressure plate (1 '') has reached the predetermined removal position (8). Device according to claim 25,
characterized,
that the signal to interrupt the process and to indicate an error is sent to the controller. Device according to claim 26,
characterized,
that the sensor (27) is queried by the control system before each changeover whether there is still a pressure plate (1) in the pull-out shaft (18) and only after its removal the device for removing a pressure plate from the plate cylinder (2) is released. Device according to one of claims 18 to 27,
characterized,
that the pull-out shaft (18) for guiding the pressure plates (1 '') is equipped with beads (15), which are coated with lubricants, which extend along the path of the pressure plates (1 ''). Device according to one of claims 18 to 27,
characterized,
that the pull-out shaft (18) has roller guides for guiding the pressure plates (1 '') distributed over its sliding surface. Device according to one or more of claims 2 to 16 and one or more of claims 18 to 29 for carrying out the method according to claims 1 and 17,
characterized,
that the feed shaft (9) and the pull-out shaft (18) are combined to form a changing system (28). Apparatus according to claim 30,
characterized,
that the feed shaft (9) and the pull-out shaft (18) have upper (12, 23) and lower areas (13, 24), the latter being pivotable together and by at least one 3-position cylinder (29) in a pull-in position, a pull-out position and a rest position can be brought. Apparatus according to claim 31,
characterized,
that the joint (31) for pivoting on the printing unit side is between the upper (12, 23) and lower areas (13, 24) and the at least one 3-position cylinder (29) is on the opposite side. Apparatus according to claim 32,
characterized,
that on the side of the changing system (28) on which the at least one 3-position cylinder (29) is arranged, there is a holder (32) which pivots the lower regions (13, 24) as a result of a power failure of the 3-position cylinder (29) prevented. Device according to one of claims 31 to 33,
characterized,
that the catch plate (22) is articulated by means of a spring-loaded hinge with a stop (30) to the lower region (24) of the pull-out shaft (18) and that a further stop (47) the catch plate (22) in the retracted position to avoid a collision with a plate cylinder (2) swings away. Device according to one of claims 30 to 34,
characterized,
that the changing system (28) by means of two cables (33) arranged on both sides with deflection rollers (34) and counterweights (35) for exposing the printing unit (3) can be moved upwards. Device according to one of claims 30 to 35,
characterized,
that a blanket holder (36) is arranged at the lower end of the changing system (28). Device according to one of claims 30 to 36,
characterized,
that the assembled and jointly pivotable lower areas (13, 24) are supported by support rollers on the bearer rings of the plate cylinder (2). Device according to one of claims 2 to 16 or 30 to 37,
characterized,
that it cooperates with the pressure roller (38) for applying a pressure plate (1). Device according to one of claims 18 to 37,
characterized,
that a pressure roller (38) is arranged such that the rear end of a pressure plate (1) after opening the trailing edge tensioning device (19) also rests on the pressure roller (38) and then pushed over the catch plate (22) to the pull-out shaft (18) becomes.

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