Patent Publication Number: US-7581494-B2

Title: Cylinder for processing sheets of printing material and printing press having the cylinder

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application claims the priority, under 35 U.S.C. §119, of German Patent Application DE 10 2005 056 116.0, filed Nov. 23, 2005; the prior application is herewith incorporated by reference in its entirety. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a cylinder for processing sheets of printing material. Such cylinders are used for punching and/or scoring and/or perforating the sheets. A printing press having the cylinder, is also provided. 
   German Patent DE 198 14 966 C2, corresponding to U.S. Pat. No. 6,651,539, describes a cylinder which includes a clamping channel, a tool plate for punching and/or scoring and/or perforating the sheets, a support plate for carrying the tool plate and a first clamping system for clamping the support plate. In the above-mentioned patent, the tool plate is referred to as a base sheet and the support plate is referred to a base plate. Furthermore, the cylinder includes a first holding device for holding a front end of the support plate, a second holding device for holding a rear end of the support plate, a third holding device for holding a front end of the tool plate and a fourth holding device for holding a rear end of the tool plate. The first holding device and the second holding device together form the first clamping system which is referred to as a blanket holding device in the above-mentioned patent. The third holding device and the fourth holding device are disposed on the support plate and are referred to as fastening bars in the above-mentioned patent. 
   It is a disadvantage of the cylinder of the prior art that the tool plate cannot be clamped onto it with accurate register. The fastening bars are comparatively unstable, which results from their configuration on the support plate and opposes improved register accuracy. 
   2. Summary of the Invention 
   It is accordingly an object of the invention to provide a cylinder for processing sheets of printing material on which a tool plate can be positioned with accurate register and a printing press having the cylinder, which overcome the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type. 
   With the foregoing and other objects in view there is provided, in accordance with the invention, a cylinder for processing sheets of printing material. The cylinder comprises a clamping channel having a central region and edge regions. A tool plate punches and/or scores and/or perforates the sheets. A support plate carries the tool plate. A first clamping system for clamping the support plate has a first holding device for holding a front end of the support plate and a second holding device for holding a rear end of the support plate. The first holding device and the second holding device are disposed in the edge regions. A second clamping system for clamping the tool plate has a third holding device for holding a front end of the tool plate and a fourth holding device for holding a rear end of the tool plate. The third holding device and the fourth holding device are disposed in the central region. 
   The configuration of the third holding device and the fourth holding device in the central region makes it possible for the third holding device and the fourth holding device to be disposed separately from the support plate. This separate configuration makes a solid and stable configuration of the third holding device and the fourth holding device possible. The solid and stable configuration is in turn advantageous with regard to clamping the tool plate onto the cylinder with accurate register. 
   As a result of the fact that the third holding device and the fourth holding device together form the second clamping system, it is possible to clamp the tool plate in a manner which is independent of the clamping of the support plate, which in turn is advantageous with regard to the register accuracy. The tool plate can be not only held firmly through the use of the second clamping system, but can also be clamped, that is to say can be tautened in the circumferential direction of the cylinder. 
   In accordance with another feature of the invention, the first holding device and the second holding device are rotatably mounted clamping shafts. 
   In accordance with a further feature of the invention, the third holding device and the fourth holding device are clamping devices which include in each case a first clamping jaw and a second clamping jaw. 
   In accordance with an added feature of the invention, the clamping devices include in each case an eccentric shaft for adjusting the first clamping jaw toward and away from the second clamping jaw. The adjustment takes place during clamping and release of the tool plate. 
   In accordance with an additional feature of the invention, the second clamping system includes a gear mechanism for moving the fourth holding device toward and away from the third holding device. The movement takes place during release and clamping of the tool plate. This gear mechanism is preferably a worm gear mechanism. 
   In accordance with yet another feature of the invention, the second clamping system includes a joint for guiding the fourth holding device toward and away from the third holding device. The guidance takes place during release and clamping of the tool plate. This joint can be a rotary joint, about which the fourth holding device can pivot, and is preferably a linear thrust joint, that is to say a linear guide. 
   In accordance with yet a further feature of the invention, the third holding device is equipped with register pins for positioning of the tool plate with accurate register. 
   In accordance with yet an added feature of the invention, the cylinder has a basic body with a fastening head for fastening the second clamping system. The fastening head protrudes into the central region. 
   In accordance with yet an additional feature of the invention, the second clamping system has a carrier plate for carrying the third holding device and the fourth holding device. The carrier plate is fastened to the fastening head. The carrier plate is preferably fastened to the fastening head through the use of screws. 
   In accordance with still another feature of the invention, the fastening head is configured to be compatible with a covering hood for covering the central region. As a result, the second clamping system can optionally be fastened to the fastening head for a first cylinder equipment state, and the covering hood can be fastened to the fastening head for a second cylinder equipment state. 
   With the objects of the invention in view, there is also provided a printing press, comprising the cylinder configured according to the invention. 
   Other features which are considered as characteristic for the invention are set forth in the appended claims. 
   Although the invention is illustrated and described herein as embodied in a cylinder for processing sheets of printing material and a printing press having the cylinder, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. 

   
     The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a diagrammatic, side-elevational view of a printing press having a cylinder; 
       FIG. 2  is an enlarged, fragmentary, partly-sectional view of the cylinder of  FIG. 1  in a first cylinder equipment state which is provided for punching and/or scoring and/or perforating, with a second clamping system being inserted into a clamping channel of the cylinder; and 
       FIG. 3  is an enlarged, fragmentary, partly-sectional view of the cylinder of  FIG. 1  in a second cylinder equipment state which is provided for printing or varnishing, with a covering hood being inserted into the clamping channel instead of the second clamping system of  FIG. 2 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring now in detail to the figures of the drawings, in which elements and components that correspond to one another are identified by the same reference symbols and first, particularly, to  FIG. 1  thereof, there is seen a printing press  25  having an impression cylinder  26  which interacts with a cylinder  1  for processing sheets  2  of printing material. After they are processed, the sheets  2  are deposited on a delivery stack which is shown in the drawing.  FIG. 2  shows that the cylinder  1  has a clamping channel  3  which includes two edge regions  5  and one central region  4  which lies between these edge regions  5  as seen in the circumferential direction. A tool plate  6  which is provided with raised dividing tool lines for dividing the respective sheet  2  and/or deforming tool lines for deforming the sheet  2 , is clamped on the cylinder  1 . The dividing tool lines can, for example, be punching lines and/or perforating lines. The deforming tool lines can, for example, be scoring lines. The tool lines can be adhesively bonded onto the tool plate  6  and are not shown in the drawing for reasons of simplifying the drawing. The tool plate  6  is flexible and can be a metal sheet or a film. A flexible support plate  7  is clamped on the cylinder  1  below the tool plate  6 . 
   The support plate  7  has a front end, which leads in the rotational direction of the cylinder  1 , and is hooked into a first holding device  9 . A rear end of the support plate  7 , which trails in the rotational direction of the cylinder  1 , is hooked into a second holding device  10 . The first holding device  9  and the second holding device  10  together form a first clamping system  8  which serves to tauten the support plate  7  in the circumferential direction while it is being clamped to the cylinder  1 . A second clamping system  11  serves to tauten the tool plate  6  in the circumferential direction while it is being clamped. The second clamping system  11  includes a third holding device  12  and a fourth holding device  13 . A front end of the tool plate  6  is clamped into the third holding device  12  and a rear end of the tool plate  6  is clamped into the fourth holding device  13 . The two ends of the tool plate  6  are not angled away in a hook-shaped manner, in contrast to the two ends of the support plate  7 . 
   The cylinder  1  has a basic body  20 , in which the clamping channel  3  is formed on the circumferential side. The basic body  20  includes a fastening head  21  which protrudes radially and is located in the central region  4 . The fastening head  21  delimits two holes which are made in the basic body  20  and are situated in the edge regions  5 . The first holding device  9  is disposed in one hole and the second holding device  10  is disposed in the other hole. The first holding device  9  and the second holding device  10  are clamping shafts which are rotated in opposite directions to one another in order to tauten the support plate  7 . 
   The third holding device  12  and the fourth holding device  13  are not disposed on the support plate  7 , but on the fastening head  21 . As a consequence, a spacing which exists between the third holding device  12  and the fourth holding device  13  is smaller than a spacing which exists between the first holding device  9  and the second holding device  10 . The third holding device  12  and the fourth holding device  13  are not only disposed more closely to one another than the first holding device  9  and the second holding device  10 , but are also disposed to lie further radially outward than the first holding device  9  and the second holding device  10 . 
   The third holding device  12  and the fourth holding device  13  each include a first clamping jaw  14  and a second clamping jaw  15 , between which the respective end of the tool plate  6  is clamped. The third holding device  12  and the fourth holding device  13  are therefore configured as clamping devices. Each of these two clamping devices includes an eccentric shaft  16  which is disposed between the first clamping jaw  14  and the second clamping jaw  15 . The eccentric shaft  16  of the third holding device  12  and the eccentric shaft  16  of the fourth holding device  13  are structurally identical to one another, but they appear to be different in  FIG. 2  because the third holding device  12  and the fourth holding device  13  are shown in that figure in a manner which is sectioned in different sectional planes from one another. During clamping of the tool plate  6  between the first clamping jaw  14  and the second clamping jaw  15  of the respective clamping device, the first clamping jaw  14  is adjusted toward the second clamping jaw  15 . The first clamping jaw  14  is adjusted away from the second clamping jaw  15  when the respective clamping device is opened again, in order to release the tool plate  6  from the respective clamping device. The eccentric shafts  16  are therefore rotated, in order to open and to close the clamping devices (third holding device  12 , fourth holding device  13 ). Each eccentric shaft  16  has a socket wrench socket  27 , as is shown in the drawing using the example of the eccentric shaft  16  of the fourth holding device  13 . A socket wrench which forms a lever and has a handle is inserted into this socket wrench socket  27  which is configured as a transverse hole, for rotating the respective eccentric shaft  16 . 
   In order to position the tool plate  6  on the cylinder  1  with accurate register, a register system is provided which includes register recesses and register pins  19  that engage into the register recesses. The register recesses are substantially U-shaped and are formed in the front edge of the tool plate  6 . The register pins  19  are inserted into the second clamping jaw  15  of the third holding device  12 . The number of register pins  19  is exactly the same as the number of register recesses, that is no more or less than two. One register pin  19  engages into one register recess and the other register pin  19  engages into the other register recess. In  FIG. 2 , only one of the two register pins  19  can be seen due to the sectional illustration which is selected for that figure. The rear edge of the tool plate  6  has no register recesses and the fourth holding device  13  has no register pins. 
   The fourth holding device  13  includes a clamping jaw carrier, in which the first clamping jaw  14  is mounted pivotably and which is mounted pivotably in the second clamping jaw  15 . The clamping jaw carrier makes it possible for the first clamping jaw  14  to be adjusted very far away from the second clamping jaw  15 , with the result that the rear end of the tool plate  6  can be introduced without problems between the first clamping jaw  14  and the second clamping jaw  15  of the fourth holding device  13 , due to this large opening width of the fourth holding device  13 . The third holding device  12  does not include a clamping jaw carrier of this type. The third holding device  12  and the fourth holding device  13  are therefore not completely structurally identical to one another. They differ from one another as a result of the presence of the register system only in the third holding device  12  and of the clamping jaw carrier of the fourth holding device  13 . 
   Through the use of a gear mechanism  17 , the fourth holding device  13  can be adjusted toward the third holding device  12  which in the process remains in its position which is stationary relative to the basic body  20 , in order to tauten the tool plate  6 , and can be adjusted in the opposite direction, in order to release the clamping of the tool plate  6 . The gear mechanism  17  is a worm gear mechanism having a threaded spindle. A joint  18  is provided in order to guide the fourth holding device  13  during its adjustment which takes place relative to the third holding device  12 . The joint  18  is a thrust joint, that is to say a linear guide, and guides the fourth holding device  13  in a secantal direction with regard to the cylinder  1 . The threaded spindle of the gear mechanism  17  is also oriented in a direction of this type. A carrier plate  22  also belongs to the second clamping system  11 . The third holding device  12  and the fourth holding device  13  are fastened to the carrier plate  22  by intermediate bars having an L-shaped profile. The carrier plate  22  can be screwed to the fastening head  21  through the use of screws  23 . 
     FIG. 3  shows the cylinder  1  in a cylinder equipment state which deviates from  FIG. 2  and in which the tool plate  6  is omitted without replacement, the support plate  7  is replaced by a cylinder cover  28  and the second clamping system  11  is replaced by a covering hood  24  for covering the central region  4  of the clamping channel  3 . The cylinder cover  28  is a rubber blanket for offset printing in the printing press  25 , in which the offset printing takes place onto the sheets  2 . The cylinder cover  28  could instead also be a varnishing blanket or a flexographic printing plate for varnishing the sheets  2  in the printing press  25 . A front and a rear end of the cylinder cover  28  are held firmly by the first holding device  9  and the second holding device  10 . The covering hood  24  includes a substantially bracket-shaped hollow profiled section which is composed of two bent metal sheets, and a carrier plate, to which the hollow profiled section is screwed. Instead of the carrier plate  22  (seen in  FIG. 2 ) of the second clamping system  11 , the carrier plate of the covering hood  24  is fastened to the fastening head  21  through the use of the screws  23 . Holes which are formed in the fastening head  21  for the screws  23  correspond both to holes which are made in the carrier plate  22  of the second clamping system  11  for the screws  23  as well as to holes which are made in the carrier plate of the covering hood  24  for the screws  23 . 
   The different cylinder equipment states result in a modular system, due to which the manufacturer of the printing press  25  can optionally equip the cylinder  1  in accordance with the specific requirements of different customers. For example, for a customer who wishes only to varnish or print the sheets  2  through the use of the cylinder  1 , but does not wish to punch, score or perforate them, the cylinder  1  is installed in its cylinder equipment state shown in  FIG. 3 , into the printing press  25  which is delivered by the manufacturer to that customer. 
   If, however, another customer wishes to punch and/or score and/or perforate the sheets  2 , the cylinder  1  is installed in its cylinder equipment state shown in  FIG. 2 , into the printing press  25  which is delivered by the manufacturer to the latter customer. However, that customer can also varnish or print the sheets  2  through the use of the cylinder shown in  FIG. 2 . To that end, the customer need only remove the tool plate  6  and the support plate  7  from the cylinder  1  and clamp a rubber blanket for offset printing or a flexographic printing plate or varnishing blanket for varnishing in place of the support plate  7 . The customer can therefore perform both print jobs which require punching, scoring or perforating of the sheets  2  and print jobs which require varnishing or printing of the sheets  2  instead, through the use of the cylinder  1 , with a low expenditure for changeover. 
   The second clamping system  11  is not used during varnishing or printing of the sheets  2  which takes place through the use of the cylinder  1 , but it remains in its installation position in the cylinder  1 .