EP1918103A1 - Device and method for finishing sheet-like substrates - Google Patents

Abstract

The module has a printed sheet e.g. substrate, fed from a transport unit to the module into a processing gap between two processing cylinders (8, 9), where the processing cylinders are gripper less. The transport unit is designed as a duplex rotating toothed chain, conveyors or winding cable, between which a pick up carrier or pneumatic suction ledges for guiding of the printed sheet at a front edge are provided. The printed sheet is guided into the processing gap between two rotating processing rollers. An independent claim is also included for a method for synchronization of a transport unit in a processing module.

Description

The invention relates to a device and a method for finishing processing according to the preambles of claims 1 and 6.

The refining of arcuate substrates, e.g. by cutting, punching, embossing can be done in a sheetfed press. In this case, the substrate can be processed in that it can be inserted between two rotating processing rollers and undergoes its processing when passing through the working gap between the processing rollers. In this case, a substrate is introduced in the form of a sheet through the processing plant with a linear drive or link chains with gripper carriages in the machining gap between the two rotating processing rollers and possibly transported away again.

Inline finishing in printing presses, for example a stamping process for the production of blanks for packaging, in direct connection to the printing and optionally painting process, are well known. The DE-PS 435 716 describes a machine for the automatic production of printed blanks for packaging of all kinds of an endless fabric web, wherein between the pressure in the printing units and the stamping plant is still a painting process.

In DE 23 41 326 discloses an apparatus which allows perforated sheet material, which is transported through the printing nip of a printing cylinder to be perforated or scored with a perforating strip or a scoring tool, which is adhered to a cylinder. This application is designed for a specific application and does not provide for the use of a stamping tool to separate individual blanks from a blank sheet. From the invention, however, it is known to guide a sheet by means of grippers which are attached to one of the processing cylinder, through the machining gap.

The US 3,383,991 describes a processing apparatus with two rotating cylinders, which are covered with flexible plates with punching and / or embossing forms and these plates form a machining gap on the cylinder by an arc is deformed or punched. In order to secure the register to the printed image, at least one cylinder has grippers which guide the sheet through the machining gap. An inline connection of this solution found directly to a printing press is not provided in this patent, but mention is the punching of printed sheets.

The DE 41 38 278 C2 describes a coating unit of a sheet-fed printing machine, which can be used either as a coating unit or as a processing unit for punching, grooving and perforating. The disadvantage of this device is that the coating unit can be used either only for processing or for painting. However, it is advisable to pre-coat printed sheets, which are to be processed mechanically, in order to avoid smearing or depositing the printing ink on the processing tool. However, this would require a double-coating machine with at least two coating units and a corresponding drying section for the drying of the paint before mechanical processing. The usual drying line for paint, namely the way from the coating unit to the sheet storage on the delivery pile can not be used with this solution found. Another disadvantage of the solution found is that in machines with double-sized counter-pressure cylinders, for example, in a stamping process with die and male, a plate on the forme cylinder on two plates, each located on the cylinder halves of the impression cylinder must be set up. This setup process is very time consuming and technically difficult to control. This is aggravated by the poor accessibility to the impression cylinder.

The DE 103 06 493 A1 discloses, inter alia, a sheet-fed press with a special stamping, which connects directly to the last printing or coating unit. Again, the drying section in the boom can not be used become. This solution found also has disadvantages if the sheet is not to be mechanically processed. Sheets must be passed through the stamping unit, which can always lead to the risk of striking the printed sheets even when moving away a machining cylinder. Also, retrofitting an existing sheet-fed press is not easy to realize by the special design of the stamping.

The DE 20 2004 018 763 U1 shows a punching and processing device, which is arranged in the arched rise of a boom. The printing sheet is conveyed completely over the cylinder until the actual punching process and only transferred to a conveyor system after mechanical processing. The advantage of this system lies in the good operability and the available space for aggregates for the disposal of waste. The disadvantage of the system found, inter alia, is the fact that it is a special unit that can be retrofitted only with great effort in an existing printing press. Also, the drying section of the boom can not be used, whereby in this solution after the coating unit or last printing unit nor a dryer module is provided. Experience in practice has shown, however, that a single dryer module for the drying of paint is usually not sufficient, apart from the missing course, which is required for a high gloss finish, as often required in the refinement of printed products.

All of these embodiments have in common, insofar as they relate to sheet-fed machines, that at least one machining cylinder is equipped with at least one gripper, which ensures the transport of the printed sheet through the machining center. This type of sheet transport has the significant advantage that a very good register can be achieved by the exact transfers of cylinders to cylinders by means of the cylinder and Transferter mounted, combing gripper strips. The mechanical engineering effort, however, is considerable, since transferters or intermediate drums are required for transport between the printing units. The sheet guiding requirements force elaborate sheet guiding boxes (Leitkästen), which hold the sheet between the printing units on the circular path, and Druckzylinderblasvorrichtungen that fix the sheet before entering the printing unit on the printing cylinder.

An alternative to the gripper transport with cylinders is to transport the sheet through the entire machine or through sections of the machine by means of a gripper carriage suspended from a chain, belt or rope.

Sheet transport systems with chain transport have been known for a long time. As early as 1892, a "rotary printing machine for the multicolored perfecting" in the DE 80616 disclosed in which the sheet is guided by transport chains. However, transport means with tooth elements, such as chains, have the disadvantage that they lengthen in operation and the tooth elements have more or less large pitch errors. Therefore, the synchronization between the printing cylinder and the gripper carriage must be ensured.

Such a sheet-processing printing machine is from the US 21 38 405 known. The chain-guided gripper carriages provided for sheet transport by the printing press with a single gripper closure are temporarily locked to the impression cylinders of the printing couples in order to synchronize the circumferential speed of the cylinder surfaces and the chains. In the DE 39 36 345 a sheet-fed printing machine is described with a device for mechanically fixing the gripper carriage, wherein the gripper carriage is suspended on support tabs on the chain and have adjustable fixing prisms and support screws, against which the support tab is pulled. There are other such fixation devices, such as those in the DE 36 36 578 Known which are to achieve a compensation of the motion irregularities with a positive engagement, but they all have the disadvantage that they are subject to a high maintenance and the quality of the register can change during the printing operation, since all these mechanical fixing systems a permanent Wear subject.

In the DE 39 36 345 selected inter alia, a wavy sheet travel by means of a continuous chain, since thus the time that is available for the synchronization between gripper carriage and impression cylinder, can be extended.

From the US 737521 or DE 19 30 317 is a further expression of a printing machine with continuous bowing known. Characteristic of the rotary printing press described in these patents is that the sheet guiding takes place with a gripper carriage mounted on an endless, rectilinear conveying means moved by the printing units, wherein a synchronization of the surface speeds of the cylinders and the conveying means without mechanical aligning elements is provided by synchronization is provided by the drives of the cylinder and the conveyor. The gripper carriage runs through freely in the passage through the printing unit. The printing units can be provided with their own drive, wherein the individual printing units are connected to each other with synchronization rods.

A sheet-fed press with flat sheet guide, in which the sheet transport is carried out with attached to conveyor belts gripper carriages, is exemplified in the DE 195 11 682 disclosed. Furthermore, a method for synchronization is disclosed, according to which signals are obtained at two spaced apart in the sheet running direction on the conveyor belt or on the sheet, and from these signals, the speed and the length of the conveyor belt are adjusted according to the speed and the circumference of the cylinder. The cylinders are driven at a constant speed. The regulation of the length adjustment of the conveyor belts is done by controlling the temperature of the conveyor belts and the guide wheels. This regulation seems very complicated and difficult to realize.

An alternative to the gripper carriages suspended on transport means, such as chains or conveyor belts, may be gripper carriages which are moved by the machine by means of a linear drive. Such a gripper carriage drive is exemplary in the DE 2501963 described. The advantage of the gripper carriage transport by means of a linear drive is that the individual gripper carriages can be controlled separately over specific sections for the purpose of error compensation. The synchronization of the gripper carriage takes place in that a signal from the cylinder is removed by means of a light pointer, which is used to control the Greiferwagenvorschubs. The synchronization takes place at a constant speed of the cylinder by a Nachsteuern the gripper carriages according to the cylinder revolution number. The linear drive offers fantastic possibilities, but also requires a high control effort. Also, the linear drive is a costly device.

In the DE 197 22 376 discloses a further embodiment of a linear drive for sheet-fed presses, which manages with a significantly lower control or energy consumption. This sheet guide system comprises two parallel guide rails, in each of which an associated, the rotor part of an electric linear drive forming driving element is guided. The drive of the propulsion elements, which are designed as link chains with magnetizable material, takes place with lying outside the guide rails drive stations with coils that form the stator of the linear drive.

The drive of the printing units can be done via gear trains or individual drives. Single drives for rotary printing machines are among others from the DE 195 27 199 "Flexographic printing machines and their use" known for flexographic printing machines. In the DE 20 46 131 Among other things, a speed control on web presses with single drives has been disclosed. In the DE 11 46 959 a single drive control for printing units of a sheet-fed printing machine has been described, which is characterized in that each printing unit is associated with its own variable speed drive. In the DE 196 23 224 is a single drive for a sheet-processing printing machine described in which only the plate cylinder and optionally the inking unit are driven by a single drive, while the blanket cylinder and plate cylinder remain mechanically connected via a gear train. In case of failure of a single drive On the sheet leading impression cylinder there is always the danger that the grippers of the individual cylinders are no longer combing each other and thus comes to a machine damage. This damage will be in the DE 196 23 224 excluded by keeping all bow-leading cylinders and the cylinders in direct contact with them coupled via the mechanical gear train. Single drives are well known for sheet and roll converting rotary presses.

In the DE 101 55 033 An apparatus for synchronizing transfers of sheet material will be described. The patent discloses a printing press in which the sheet material transport system has its own drive which is driven independently of the cylinders at the sheet processing stations of the sheet processing machine. It is provided for at least one synchronization of the sheet material conveying conveyor and the cylinder. The cylinders also have a single drive. The synchronization between gripper carriage and cylinder takes place essentially by means of a synchronization gear. The registration accuracy is achieved by complex synchronized drives. The combination of a single drive with a sheet transport by means of gripper carriage, driven in this patent by a linear drive within a printing machine is therefore known.

The object of the invention is to provide a processing module for inline processing of printed sheets in printing presses by mechanical processing of the printing sheet, such as stamping, embossing, grooves or perforations, in which the sheet is introduced without gripper transfer to a machining cylinder for processing in the machining gap. In addition, the invention describes means for synchronization between transport and the one or more processing cylinders.

The object is achieved by a device according to the features of claim 1 and a method according to the features of claim 6.

Advantageous developments emerge from the subclaims.

The invention accordingly relates to an apparatus and a method for finishing of sheet-shaped substrates, e.g. Cutting, punching, embossing in a sheet-fed printing machine, wherein the substrate undergoes its finishing processing by being insertable between two rotating processing rolls and undergoing its processing as it passes through the working nip between the processing rolls. In this case, the sheet is introduced through the processing plant with a linear drive or link chains with gripper carriages in the machining gap between the two rotating machining rollers and possibly transported away again.

The solution found invention provides to introduce the sheet by a means of transport in the machining gap of a processing plant for mechanical processing of a sheet in printing presses without the sheet is passed from the transport to one of the rotating cylinder machining.

Means of transport according to the invention may be link chains with gripper carriages, conveyor belts or gripper carriages, which are moved by means of a linear drive.

The great advantage of the solution found according to the invention is that this solution can be integrated into a boom of a sheet-fed press without a major structural change, without necessarily the transport devices, such as the chain guide in a boom, must be reconstructed consuming. Since the transport device with the sheet passes through the processing station, the processing module can be integrated later with an acceptable cost in an existing boom configuration.

The single drawing for this purpose uses the list of reference numerals to show the elements for forming a device according to the invention.

A boom 1 joins a printing unit with a forme cylinder 2 and a counter-pressure cylinder 3. A sheet guiding cylinder 4 transfers the printing sheet to a gripper carriage conveying system 5, which conveys the printing sheet in the direction of a delivery stack 7. Another chain conveyor system 6 is provided for storing the processed printing sheet on the delivery stack 7.
In the area of the conveyor systems 6, 7 a processing module with a lower processing cylinder 8 and an upper processing cylinder 9 is arranged.
The processing module is used, for example, punching, grooving, perforating or embossing the printed sheet. When punching a suction device 10 is used to remove punching waste from the upper processing cylinder 9. In addition, broken-off waste can be disposed of via a discharge device 12 in a waste display 11.
For arc treatment for better machinability in the processing module, a UV radiation dryer 13 and / or an infrared dryer 14 may be arranged in the region of the gripper carriage conveyor system 5.
The unit is arranged as a module 15 in the boom 1.
The upper and lower processing cylinders 8, 9 are arranged here with their working gap at the level of the lower movement path of the gripper carriage conveyor system 4 and the chain conveyor system 6. The processing cylinders 8, 9 have no gripper devices. The printed sheets are conveyed by a conveyor system in the plane of the working gap between the processing cylinders 8, 9 through the working gap.
Therefore, here also a single continuous conveyor system can be provided which guides the sheet in a gripper closure by the processing module.

At least one cylinder of the machining module in this case has a pit, which allows the passage of the means of transport, for example a laterally suspended gripper carriage, without collision with the processing cylinders.

Only the synchronization between the processing module and the transport device must be ensured. Transport means with tooth elements, such as chains, have the disadvantage that they lengthen in operation and the tooth elements have more or less large pitch errors.

In a simple application, for example, if the processing module is to be used only for punching, the passage of the sheet can be unsynchronized, because the requirements on the punching accuracy are usually much lower than the required register accuracy in the print. If, for example, you want to perform an embossing that must be carried out in register with the printed image, measures must be taken to synchronize the means of transport and the position of the processing plant. Register accuracy of chain transfer systems can be improved by using selected and pre-stretched chains. The disadvantage is that such high-quality chains are usually much more expensive than the chains commonly used.

Another approach is to allow a certain positional tolerance of the means of transport and to ensure with appropriate measures the synchronization when passing through the machining gap. This can be done, for example, by temporarily locking the transport means with a processing cylinder. One common approach for gripper carriage chain guides is that they are suspended from the chain with support tabs and that these support tabs are aligned against mechanical means such as stop screws or prisms. There are also other mechanical possibilities conceivable, for example, in the case of a gripper carriage transport with gripper carriage this itself has a mating surface which is aligned with one or more mating surfaces in the cylinder pit at least one machining cylinder.

Another possibility of synchronization is that the position of the gripper carriage system or of the transport means before entry into the machining gap of the processing unit is detected by one or more suitable encoders and the position tolerances is corrected by a position correction of the machining cylinder. This solution has the advantage that tolerances are allowed in the means of transport and the error correction takes place via the cylinder position of the processing plant. A certain error that may well change during the production period is therefore permitted and controlled by the individual drives in the machining center.

One approach to implement such a concept is that at least one machining cylinder or both machining cylinders have a controllable single drive, which can change the position of the machining cylinder dynamically. The controllable individual drive then receives its desired position specifications from the encoders or the encoder, which detects the position of the means of transport, for example a gripper carriage, before entering the processing plant. The solution is also easy to implement in practice, since small positional deviations, which are quite acceptable, for example, on the route between position detection of the means of transport and the inlet to the processing cylinder in view of the required tolerances.

The signal detected by the encoder (s) is used to move the individual drive or the individual drives of the machining module so that the machining cylinders and the transporting means are synchronized with one another and permit a trouble-free passage of the transporting means through the machining module. This is an embodiment of a single drive control with a real master axis, wherein the master signal is supplied by the position determination of the means of transport, for example a gripper carriage, or by the position determination of the sheet before entering the processing module.

There is a collision problem in the case of the failure of a single drive or a non-timely arrival of the means of transport, for example a gripper carriage, on the processing module. The error signal may once come from a single drive by an error signal, such as engine failed, will pass to an emergency control and immediately from this emergency control an emergency program for collision avoidance is initiated. The other fault, no correct position of the gripper carriage, can be detected, for example, if at least one encoder is positioned in front of the printing tower, which the gripper carriage must pass within a narrow time window. If the time window is exceeded or if the gripper carriage comes too early and if the deviation is so great that no correction by the individual drive or the individual drives is possible in the remaining time window, the identical emergency program is executed, as in the case of the failure of a single drive motor.

The solutions for the emergency program may vary depending on the drive concept of the individual cylinders. One possibility is that the processing cylinders are spontaneously parked so far that the gripper carriage can pass through the processing plant without major damage. When using a single drive without a mechanical coupling of the processing plant via a gear train or other suitable power transmission method with the printing units or coating units of the printing press, such a repositioning movement is easier to implement. The shutdown can be done pneumatically, hydraulically, electrically via a motor or via a linear drive.

Another solution is that the machining center with a resilient gear or a gear with a relatively large backlash is engaged with the machine, so that in any case, for example in case of failure of a single drive, the collision-free passage of the transport is ensured. The individual drive can then perform a synchronization of transport or printing sheet and processing cylinder only in the context of gear or Federspiels. With the expected relatively small positional deviations, this solution would offer a high level of security coupled with good synchronization.

After passing through the processing module in the punching operation, the entire punched sheet can be transported on and placed on a discard pile. Alternatively, the sheet can be separated after passing through the machining gap in at least one good and at least one waste part be, optionally with the use of spreading agents. The passing through the processing module transport can be used after separation into at least one good and at least one waste part for removal to at least a portion of the waste part.

LIST OF REFERENCE NUMBERS

1

boom

2

form cylinder

3

Impression cylinder

4

Sheet guiding cylinder

5

Gripper bar conveyor system

6

Chain Conveyor System

7

delivery pile

8th

processing cylinder

9

processing cylinder

10

suction

11

waste delivery

12

diverter

13

UV radiation dryer

14

infrared dryer

15

module

Claims (8)

Editing module for editing, eg. As punching, grooving, perforating or embossing of printed and possibly painted sheet in a printing machine, wherein the processing module is a rotation processing device, wherein the sheet is inserted into a machining gap between two rotating processing rollers and when passing through the machining gap by effective tool parts undergoes its processing,
characterized by
that both processing cylinders are clawless and the signature is introduced by a transport means to the processing module and into the processing gap between the two processing cylinders. Processing module according to claim 1,
characterized by
that the transport means is designed as a double-sided circulating toothed chains, conveyor belts or conveyor cables, between which gripper carriages or pneumatic suction strips are provided for guiding the printed sheets at the front edge. Processing module according to claim 1,
characterized by
in that at least one machining cylinder has a cylinder pit which permits a collision-free passage of the transport means through the machining gap. Processing module according to claim 1,
characterized by
that at least one processing cylinder has a controllable single drive. Machining module according to claim 1 and 4,
characterized by
that the processing module is connected to the printing press via a gear with a relatively large amount of toothed air or a resilient gear, which usually takes place via the drive and the mechanical coupling only serves to avoid a collision between the processing module and means of transport in case of failure. Method for the synchronization of means of transport in a processing module according to claims 1 and 4,
characterized by
in that synchronization takes place according to the principle of a real master axis, by determining the position of the means of transport or the position of the signature before the entry through one or more encoders and that the obtained signal or the signals obtained are used for position control of the processing module such that Transport means and processing module are synchronized exactly or within certain tolerance limits to each other. Method according to Claim 6 for the synchronization of means of transport,
characterized by
that synchronization is effected by mechanical stops or prisms of at least one processing cylinder, at which the transport means aligns. Method according to claim 6 for collision avoidance,
characterized by
that in the case of failure of a drive of the machining module or an error in the transport at least one processing cylinder is spontaneously turned off so far pneumatically, electrically, hydraulically or mechanically that no risk of collision with the transport more prevails.

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