Patent Publication Number: US-2005139312-A1

Title: Corrugating machine

Description:
This is a continuation of copending parent application Ser. No. 10/235,941, filed Sep. 6, 2002. 
    
    
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The invention relates to a corrugating machine for the manufacture of sheets of corrugated board.  
      2. Background Art  
      Corrugating machines for the manufacture of single-faced corrugated board or multi-layered corrugated board have been known for quite a while, for instance from U.S. Pat. No. 5,632,850. The output of a corrugating machine can be raised by increasing the velocity of the corrugated board. However, there are upper limits to this. If a further increase in production is intended, another separate corrugating machine must be made available.  
     SUMMARY OF THE INVENTION  
      It is an object of the invention to embody a corrugating machine of raised manufacturing capacity.  
      The object is attained in a corrugating machine for the manufacture of sheets of corrugated board, comprising a first manufacturing unit for the production of a first web of corrugated board; at least a second manufacturing unit for the production of an at least second web of corrugated board; a mounting unit, which is disposed downstream of said manufacturing units in a direction of working, for non-adhesively bringing together the first web of corrugated board and the at least second web of corrugated board; and at least one working unit, which is disposed downstream of the mounting unit, for jointly working the first web of corrugated board and the at least second web of corrugated board which lie on top of each other. The gist of the invention resides in that at least two webs of corrugated board are produced separately, which are then brought together and worked jointly.  
      Further details of the invention will become apparent from the ensuing description of two exemplary embodiments, taken in conjunction with the drawing. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       FIG. 1  is a view of a first portion of a corrugating machine according to a first embodiment;  
       FIG. 2  is a view of a second portion of a corrugating machine according to the first embodiment;  
       FIG. 3  is an illustration of a detail, on an enlarged scale, of two webs of corrugated board one above the other that have been brought together; and  
       FIG. 4  is a view of a second portion of a corrugating machine according to a second embodiment. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      The following is a description of a first embodiment of the invention with reference to FIGS.  1  to  3 . A corrugating machine, which is diagrammatically outlined in  FIGS. 1 and 2 , comprises a machine  1  for the manufacture of single-faced corrugated board. The machine  1  has an unroll stand  2  for a medium  3  which, for a corrugation to be produced, is passed between two neighboring fluted rollers  4 . Then the tips of the corrugated medium  3  are glued in an adhesive applicator unit  5  and the corrugated medium  3  and a backer  7  from an unroll stand  6  are pressed together and joined in a nip between a nip roller  8  and a fluted roller  4 . A single-faced corrugated board is discharged upwards from the machine  1  and deviated by a deflection roller  10  in a working direction  11 . The machine  1  for the manufacture of single-faced corrugated board is generally known, for instance from U.S. Pat. No. 5, 632,850, GB 2,305,675 A, or DE 43 05 158 A1, which reference is made to for any details.  
      An unroll stand  12  for a liner web  13  is disposed downstream of the machine  1  in the working direction  11 , the liner web  13  first being led upwards and deviated by a deflection roller  10  and then conveyed in the working direction  11 . The corrugated medium  3 , the backer  7  and the liner  13  are appropriately selected paper webs. Disposed downstream of the unroll stand  12  in the working direction  11  is a machine  14  for the production of a web of single-faced corrugated board  15 , the machines  1  and  14  being identical in design.  
      The web of corrugated board  15  is discharged upwards from the machine  14 , deviated by the deflection roller  10  and then conveyed in the working direction  11 . An unroll stand  16  for a liner web  17  is disposed down-stream of the machine  14 , the liner  17  being discharged in the working direction  11 . A preheater  18  is disposed downstream of the unroll stand  16 , having four heating rollers  19  one above the other. The web of corrugated board  9 , the liner web  13 , the web of corrugated board  15  and the liner web  17  run one above the other, partially contacting the respective heating rollers  19 . Disposed downstream of the preheater  18  is an adhesive applicator unit  20  with two glue rollers  21  one above the other which are partially located in a glue pan  22 . The corrugated mediums  3  of the webs of corrugated board  9  and  15  are in contact with the respective glue rollers  21 .  
      Disposed downstream of the adhesive applicator unit  20  is a heater  23  which comprises a horizontal hot plate table  24  extending in the working direction  11 . Provided above the table  24  is a heated, continuous hold-down belt  26  which is deflected by three rollers  25 , with a nip  27  formed between the hold-down belt  26  and the table  24 , where the web of corrugated board  9 , the liner  13 , the web of corrugated board  15  and the liner  17  are passed through and pressed together. A corresponding heater  23  is known from U.S. patent application Ser. No. 09/711 957.  
      Two three-layered webs of corrugated board  28  and  29  are formed in the heater  23 , lying one above the other without being glued. The arrangement of the two webs of corrugated board  28 ,  29  is illustrated in detail in  FIG. 3 , there being however no real gap between the webs of corrugated board  28  and  29  because the two webs lie directly one upon the other. The gap illustrates that the webs of corrugated board  28  and  29  are not united, but lie loosely one on top of the other.  
      The machine  1 , the unroll stand  12 , parts of the preheater  18  and of the adhesive applicator unit  20  as well as the part of the heater  23  necessary for adhesively mounting the web of corrugated board  9  to the liner  13  constitute a first manufacturing unit for the production of the web of corrugated board  28 . The machine  14 , the unroll stand  16 , parts of the preheater  18  and of the adhesive applicator unit  20  as well as the part of the heater  23  necessary for adhesively mounting the web of corrugated board  15  to the liner  17  constitute the second manufacturing unit for the production of the web of corrugated board  29 . The heater  23  is a mounting unit for non-adhesively bringing together the web of corrugated board  28  and the web of corrugated board  29 .  
      Disposed downstream of the heater  23  is a lengthwise cutting/grooving unit  30 , composed of two successive grooving stations  31  as well as two successive length-wise cutting stations  32 . The grooving stations  31  have grooving tools  33  which are disposed in pairs above each other with the webs of corrugated board  28  and  29  being passed there-between. The lengthwise cutting stations  32  have rotatably drivable cutters  34  for engagement with the webs of corrugated board  28 ,  29  for them to be cut longitudinally. The detailed structure of the grooving station  31  and the length-wise cutting station  32  is known from U.S. Pat. No. 6,071,222 as well as DE 101 31 833.2, which reference is made to for information on the detailed design.  
      Downstream of the unit  30  in the working direction  11 , provision is made for a crosscutting unit  35  which has two rotatably drivable rollers  36  one above the other, each carrying a cutter bar  37  that extends radially outwards vertically of the direction  11 , the cutter bars  37  cooperating for crosscutting the webs  28  and  29 . Provided directly downstream of the crosscutting unit  35  is a conveyor belt  39  that is deflected around rotatably drivable rollers  38 . Downstream of the conveyor belt  39 , provision is made for a deposit  40  with a vertical stop  41  where the corrugated boards  42  are piled up on a stack  43 .  
      The following is a description of the mode of operation of the corrugating machine according to the first embodiment. In the machine  1 , a web of single-faced corrugated board  9  is produced and supplied to the preheater  18  in the working direction  11 . Simultaneously, the liner  13  is spun off the unroll stand  12  and also supplied to the preheater  18  in the direction  11 . The same takes place in the machine  14  and with the liner web  17 . In the preheater  18 , the four webs  9 ,  13 ,  15  and  17  are initially heated and then the corrugated bottom sides of the webs  9  and  15  are glued in the adhesive applicator unit  20 . In the heater  23 , the liner web  13  is held down on the web of corrugated board  9  for them to be united. Simultaneously, the liner web  17  is pressed against the web of corrugated board  15  for these two to be united. In this way the three-layered webs of corrugated board  28  and  29  originate. It is also the function of the heater  23  to bring the webs of corrugated board  28  and  29  together so that two webs of corrugated board lie one on top of the other in the working direction  11  without the webs of corrugated board  28  and  29  being joined, in particular glued, together. In the stations  31 ,  32  as well as the unit  35 , the webs  28  and  29  that lie on top of each other are simultaneously worked by the grooving tools  33 , the cutters  34  as well as the cutter bars  37 . The advantage resides in that two webs of corrugated board  28 ,  29  that lie one on top of the other can be worked simultaneously by a lengthwise cutting/grooving unit  30  and a crosscutting unit  35 , both of which are necessary for working a web of corrugated board. Consequently, twice the quantity of corrugated board can be worked while the number of working units  30 ,  35  and the velocity of the web of corrugated board remain the same. Downstream of the crosscutting unit  35 , the corrugated boards  42  are imbricated on the conveyor belt  39  and stacked against the stop  41  on the deposit  40 .  
      Even a higher number of webs of corrugated board can be brought together in the heater  23 . It is conceivable to provide a third machine that is identical with the machine  1  as well as another unroll stand that is identical with the unroll stand  12  in order for three webs of corrugated board, which lie one on top of the other without being joined to each other, to be brought together in the heater  23 , which is a factor three increase in output. It is also possible to bring together the webs of single-faced corrugated board  9  and  15  instead of the respective three-layered webs of corrugated board  28  and  29 . In this case, there is no need of the liners  13  and  17  and the associated unroll stands  12  and  16 . The heater  23  is not necessary for bringing together the webs of corrugated board  9  and  15 . The webs of corrugated board  9  and  15  can be passed, and brought together, through a nip between two rollers that are disposed one above the other. The design of the mounting unit is a lot simpler in this case.  
      For the machine seen in  FIG. 1  to be put into practice, resort may be made to an available machine for the manufacture of seven-layered corrugated board, with a corrugated medium being regularly arranged between two smooth paper webs in the seven-layered corrugated board. A machine for the manufacture of seven-layered corrugated board comprises three successive machines for the manufacture of single-faced corrugated board, with the first machine corresponding to the machine  1  and the third machine to the machine  14 . The second machine is operated such that only the liner  13  is spun off, there being no corrugated medium.  
      The following is a description of a second embodiment of the invention, taken in conjunction with  FIG. 4 . Identical parts have the same reference numerals as they have in the first embodiment, to the description of which reference is made. Parts that vary but are constructionally identical have the same reference numeral provided with a prime. The corrugating machine in the second embodiment is composed of the first portion according to  FIG. 1  and the second portion according to  FIG. 4 . The essential difference from the first embodiment resides in that, downstream of the lengthwise cutting stations  32 , a shunt  44  is inserted where the two webs of corrugated board  28  and  29  are again separated. They are respectively supplied to a lower pair of crosscutting rollers  45  and an upper pair of crosscutting rollers  46 , the cutter bars  37  serving for crosscutting the web of corrugated board  28  and  29 , respectively. The upper pair of rollers  46  is followed by another conveyor belt  39  which stacks the sheets of corrugated board  42  on the deposit  40 ′. The arrangement according to the second embodiment is necessary when the webs of corrugated board  28  and  29  are printed, and crosscutting the webs of corrugated board  28  and  29  cannot take place simultaneously and by the same cutter bars  37  as in the first embodiment. The arrangement according to the second embodiment serves to work printed webs of corrugated board  28  and  29 , with the prints varying in position on the webs of corrugated board  28  and  29 .