Abstract:
An arrangement for producing stack bundles from signatures includes a horizontal stack deposit support, a conveyor to supply a flow of signatures to the stack deposit support for formation of a signature stack having a front end and a back end, and a supporting device adapted to form a stack bundle having a front end and a back end. The supporting device comprises a first support element adapted to rise from below the stack deposit support and act on the front end of the stack, a second support element adapted to rise from below the stack deposit support and act on the back end of the stack bundle, and a third support element arranged to rise from below the stack deposit support in a first location to act on the front end of the stack and in a second location to act on the front end of the stack bundle.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application claims the priority of European Patent Application with Serial No 02405851.3-1256, filed on Oct. 2, 2002, the subject matter of which is incorporated herein by reference. 
   BACKGROUND OF THE INVENTION 
   In stack bundling machines, the discharge area of a printing press for signatures may discharge signatures in a scaled flow and be connected to arrangements for taking over the discharged signatures to accumulate and shape them into configurations suitable for storage. For example, the discharged signatures may be shaped as bundles for further processing into various printed products such as magazines, newspapers, brochures, and any other printed products containing the signature bundles. EP 0 623 542 A1 describes examples of stack bundling machines such as the stack bundling machine marketed by Muller Martini Holding AG under the commercial name “AVANTI.” 
   However, processing steps in stack bundling machines, e.g., removing the products from a printing machine and preparing them for further processing by shaping them as bundles, are time-consuming and often unreliable. Thus, it is desirable to develop a high capacity stack bundling machines that operate reliably and have shorter cycle times, more selection options with respect to the bundle length and shorter residual bundles. 
   SUMMARY OF THE INVENTION 
   It is the object of the invention to create an arrangement with which the above described goals can be achieved. 
   The above and other objects are achieved by an arrangement for producing stack bundles from signatures, comprising a horizontally extending stack deposit support, a conveyor to continuously supply a scaled flow of the signatures to the stack deposit support for formation of a signature stack, a multi-part supporting device comprising first, second and third support elements, a compressing machine, and a bundle strapping machine. The supporting device is arranged to form a stack bundle by engaging the stack from below, and the stack bundle has a front end and a back end with respect to a direction of a movement of the stack bundle through the arrangement. The first and second support elements are arranged to act on the front end and the back end of the stack bundle, respectively, and arranged to be raised from below the stack deposit support to above the stack deposit support. The third support element is arranged to be raised and act on the front end of the stack bundle. The supporting device is arranged to transfer the stack bundle to the compressing machine by moving the stack bundle from a waiting position to a transfer position along the stack deposit support. The compressing machine is arranged to transfer the stack bundle to the bundle strapping machine. 
   The third support element can be controlled to move independently of the first and second support elements along the stack deposit support. By having the third support element with its independent mobility, a higher production can be achieved in the arrangement. 
   A separating device assigned to the first and second support element can be used to form a separating gap between the signatures supplied in a scaled flow by raising the first and second support elements into the separating gap simultaneously. Thus, the separating device separates two otherwise adjacent signatures for insertion of the first and second support elements in-between. 
   A bundle strapping machine can be operationally connected to the stack deposit support for strapping the stack bundles with at least one band extending in the direction of the movement of the stack bundle through the arrangement. The compressing machine can transport the stack bundle held between the compressing component and the spaced-apart compressing component to the strapping machine. By using the compressing machine and/or by compressing the bundles before the strapping operations of the bundle strapping machine, a saving in cycle times can occur within the arrangement. 
   A guide extending parallel to the stack deposit support can be used for moving the support elements of the supporting device along the stack deposit support. The guide can have a simple design. 
   An end-plate feeding mechanism can be arranged on the stack deposit support to reinforce the ends of the stack bundle with end plates. With the stack bundle being in the transfer position, a back end plate assigned for the back end of a stack bundle can be supplied at a gap between the second support element resting against the back end of the stack bundle and the spaced-apart compressing component assigned to the back end of the stack bundle. Thus, a reliable end-plate positioning on the stack deposit support is ensured. 
   A front end plate assigned to the front end of a stack bundle can be transported in a direction opposite to the movement direction of the stack bundle through the arrangement by being carried inside a space formed between the second and third support elements on the stack deposit support. 
   With the stack bundle being in the transfer position, the end plate-feeding mechanism can be arranged between the compressing components of the compressing machine, thus making it possible to produce stack bundles of any desired length. In an exemplary design of the compressing machine, rails extend above the stack deposit support and parallel thereto so that the compressing machine can move back and forth along the rails. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing description of the invention will be apparent from the following, more particular description of embodiments of the invention, as illustrated in the accompanying drawings, wherein like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. 
       FIG. 1   a  is a schematic representation of an arrangement according to the invention at the start of producing stack bundles of signatures. 
       FIG. 1   b  is a schematic representation of the arrangement according to  FIG. 1   a , showing an end plate moved closer to a front end of a stack. 
       FIG. 1   c  is a schematic representation of the arrangement with an end plate resting against the front end of the stack; 
       FIG. 1   d  is a schematic representation of the arrangement with an increasing stack length. 
       FIG. 1   e  is a schematic representation of the arrangement with support elements raised into a separation gap in the stack. 
       FIG. 1   f  is a schematic representation of the arrangement where a stack bundle is separated from the stack and is in a transfer position for being taken over by a compressing machine. 
       FIG. 1   g  is a schematic representation of the arrangement where a back end plate has been supplied between a compressing component of the compressing machine and a support element. 
       FIG. 1   h  is a schematic representation of the arrangement where the stack bundle is clamped between two end plates. 
       FIG. 1   i  is a schematic representation of the arrangement with the stack bundle located in a bundle strapping device and the supporting device taking over a front end plate. 
       FIG. 1   j  is a schematic representation of the arrangement showing a start of a bundle strapping operation by the bundle strapping device and the front end plate moved closer to the front end of the stack. 
       FIG. 1   k  is a schematic representation of the arrangement with the front end plate resting against the front end of the stack. 
       FIG. 1   l  is a schematic representation of the arrangement with the stack bundle being removed from the bundle strapping machine. 
       FIG. 2  is a three-dimensional representation of an exemplary embodiment of a drive arrangement for a supporting device according to the invention. 
       FIG. 3  is a three-dimensional representation of an exemplary support structure for a compressing component of a compressing machine according to the invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIGS. 1   a  to  1   l  depict an arrangement  1  for producing stack bundles  2  by continuously supplying signatures  4  in a scaled flow  3  from a conveyor as represented by an arrow  50 . The conveyor  50  can supply vertically aligned (i.e., upright) signatures  4  to a horizontal stack deposit support  5  after arranging the signatures  4  in a desired scaled formation. Such operations are described in EP 0 623 542 A1, the subject matter of which is incorporated herein by reference in its entirety. Following the printing press, the scaled formation should be laterally turned by 180°. 
   If the scaled formation is to be processed by a roller, a rewinding to another roller is unavoidable.  FIGS. 1   a  to  1   l  show that the arrangement  1  can be designed to have wheels for being transportable and, thus, connectable to the discharge areas of different printing presses within a plant. 
   In  FIG. 1   a , the arrangement  1  is shown in an empty state having an incoming, scaled flow  3  of signatures. A first support element  6  of a multi-part supporting device  7  is raised above the stack deposit support  5 . A second support element  8  and a third support element  9  of the multi-part supporting device are also raised above the stack deposit support  5 . Each of the support elements  6 ,  8 ,  9  of the multi-part supporting device  7  can be independently driven along the stack deposit support  5  with the aid of a guide  10 , the guide  10  being arranged below and parallel to the stack deposit support  5 . The movement of the support elements  6 ,  8 ,  9  along the stack deposit support  5  can be facilitated by using any known traction means such as toothed belts and chains driven along the stack deposit support  5  in a direction of a movement of the stack bundles through the arrangement. Controlled adjustment means such as traversing gears operated in conjunction with pneumatic cylinders can be used for raising and lowering the support elements  6 ,  8 ,  9  with respect to the stack deposit support. Compressing components  22  and  28  of a compressing machine  19  can be arranged above the stack deposit support  5  for gripping and transporting a stack bundle on the stack deposit support  5  to an adjacent strapping machine  20  by moving along the stack deposit support  5 . 
   At the start of the stack formation, the second and third support elements  8 ,  9  of the multi-part supporting device  7  are moved to a position above the stack deposit support  5  and takes over an end plate  29  assigned to a front end of a respective stack bundle with respect to a direction of a movement of the stack bundles through the arrangement. The front end plate  29  can be taken from a plate magazine (represented by the arrow  70  in  FIG. 1   a ) on the side of the arrangement  1  and deposited between the spaced-apart, second and third support elements  8 ,  9 . The front end plate  29  between the second and third support elements  8 ,  9  is guided along the stack deposit support  5  to the front end of the stack of signatures held in an upright, vertical position by the first support element  6 . 
   In  FIG. 1   b , the second support element  8  has moved away from the stack deposit support  5  in a downward direction and the front end plate  29  for reinforcing the front end of the stack is held between the first and third support elements  6  and  9 . In this way, the stack formation against the first support element  6  is maintained. 
   In  FIG. 1   c , the first support element  6  of the multi-part supporting device  7  has moved downwardly so that the front end plate  29  supported by the third support element  9  comes to rest against the front end of the stack. 
   In  FIG. 1   d , while the stack on the stack deposit support  5  continues to grow, the first and second support elements  6 ,  8  move to their starting position in front of a back end of the stack with respect to the movement direction of the stack. 
   In  FIG. 1   e , a stack bundle  2  has formed between the front end plate  29 , which is held in the upright standing position by the third support element  9 , and the second support element  8 , by moving and raising the first and second support elements  6  and  8  from their starting position to a separation position. In placing the first and second support elements  6  and  8  into the separating position, a separating device, which is represented by an arrow  60  and is well known, can be used. An exemplary embodiment of the separating device  60  is disclosed in EP 0 623 542 A1. In its operation, the separating device  60  can create a gap in the stack formation for inserting the first and second support elements  6 ,  8  jointly. By inserting the first and second support elements into the gap, the first support element  6  takes over the function of supporting the front end of the increasing stack and the second support element  8  supports the back end of the stack bundle  2 . 
   In  FIG. 1   f , with the length of the stack continuing to increase, the second and third support elements  8  and  9  have moved the stack bundle  2  from a waiting position to a transfer position of the stack bundle where it is to be taken over by the compressing components  22 ,  28  of the compressing machine  19 . The waiting position of the stack bundle is any position where the stack bundle is not in the transfer position. 
   In  FIG. 1   g , the stack bundle  2  in the transfer position is located between the two compressing components  22 ,  28  of the compressing machine  19 , and a back end plate  30  for reinforcing the back end of the stack bundle is supplied from an end-plate magazine  70  into a gap between the second support element  8  and the compressing component  22  (for acting on the back end of the stack bundle). The front and back end plates  29  and  30  can have the same dimensions. 
   In  FIG. 1   h , the second and third support elements  8 ,  9  can be simultaneously removed so that the front end compressing component  28  and the back compressing component  22  can press against the front and back end plates  29 ,  30 , which in turn press against the front and back ends of the stack bundle  2 . Meanwhile, the stack formation resting on the first support element  6  continues to increase in length. 
   In  FIG. 1   i , the second and third support elements  8 ,  9  have arrived at the end plate magazine  70  for taking over a front end plate  29 . The stack bundle  2  has been gripped by the front and back compressing components  22 ,  28  and moved to the bundle strapping machine  20  along rails  27 . 
   In  FIG. 1   j , the front end plate  29  has moved to the front end of the continuously increasing stack, the stack bundle  2  in the strapping machine  20  is compressed for the last time and is subsequently strapped and/or tied together. 
   In  FIG. 1   k , the front end plate  29  rests against the front end of the stack and is supported by the third support element  9 . The first and second support elements  6 ,  8  have been lowered to below the stack deposit support  5 , and the strapping operation is completed. 
   In  FIG. 11 , the stack bundle  2  is removed from the strapping machine  20 . The first and second support elements  6 ,  8  has returned to the starting position where a new stacking process has already started as also shown in  FIG. 1   d . The processing step in  FIG. 11  is followed by the step shown in  FIG. 1   f . Thus, the stack bundling processes can be repeated continuously. 
   In  FIG. 2 , an exemplary embodiment of a traction means/drive for moving the multi-part supporting device  7  along the stack deposit support  5  is shown. As to the support elements of the supporting device  7 , only the third support element  9  is depicted. The side guide  10  attached to a frame for the arrangement  1  and a traversing gear  11  for the third support element  9  are shown. The third support element  9  has three supporting plates  13  and can be lowered and raised on the traversing gear  11  with the aid of two stanchions  12  and a pneumatic cylinder (not shown). The third support element  9  can be driven by a toothed belt  14  along the stack deposit support  5 , wherein the upper as well as the lower run of the toothed belt  14  are shown. The toothed belts  15  and  16  are provided for driving the first and second support elements  6  and  8 , respectively. Each of the toothed belts  15 – 17  is wound around respective pulleys, one of which is connected to a drive motor. The gear motors  17  and  18  are assigned to the toothed belts  16  and  14 , respectively. A drive motor for the toothed belt  15  can be located at an opposite end of the stack deposit support  5  in relation to the depicted end of the toothed belt  15 . The first and second support elements  6 ,  8  can be mounted on traversing gears (not shown in  FIG. 2 ) similar to the traversing gear  11  of the third support element  9  and moved up and down the respective traversing gears by a pneumatic cylinder in the same way that the third support element  9  moves up and down the traversing gear  11  with the aid of a pneumatic cylinder. 
   In  FIG. 3 , an exemplary embodiment of a support structure for a back end compressing component  22  of the compressing machine  19  is shown. The back end compressing component  22  has back end compressing plates  31 , wherein the depicted side of the back end compressing plates  31  faces the movement direction of the stack bundles and can be arranged to press against the back end of a respective stack bundle. The back end compressing component  22 , which together with the front end compressing component  28  forms the compressing machine/arrangement  19 , is shown in its starting position in  FIG. 1   a  and moves along the stack deposit support  5  in the movement direction of the stack bundles. The support structure for the back end compressing component  22  extends crosswise to the movement direction of the stack bundles and is arranged to move on its two rollers  23  on each side of the support structure along a stationary C-shaped rail (not shown). The rail  27  (see  FIG. 1   a ) can be provided with a steering rack (not shown) on its bottom, and the steering rack can engage a gearwheel  24  of a traversing gear  25  for moving the support structure along the rail  27 . The compressing plates  31  can be adjusted to a format of the signatures  4  by a guide rod  26 , which is positioned above the compressing plates  31  and crosswise to the direction of the movement of stack bundles in the arrangement. The operating range for the compressing machine  19  (i.e., compressing and moving along the rail  27 ) extends from any point along the stack deposit support  5  to the end of the bundle strapping machine  20 . 
   The embodiments illustrated and discussed in this specification are intended only to teach those skilled in the art the best way known to the inventors to make and use the invention. Nothing in this specification should be considered as limiting the scope of the present invention. All examples presented are representative and non-limiting. The above-described embodiments of the invention may be modified or varied, without departing from the invention, as appreciated by those skilled in the art in light of the above teachings. It is therefore to be understood that, within the scope of the claims and their equivalents, the invention may be practiced otherwise than as specifically described. 
   The invention has been described in detail with respect to preferred embodiments, and it will now be apparent from the foregoing to those skilled in the art, that changes and modifications may be made without departing from the invention in its broader aspects, and the invention, therefore, as defined in the appended claims, is intended to cover all such changes and modifications that fall within the true spirit of the invention.