Patent Publication Number: US-11649132-B2

Title: Layboy having at least one diverted belt section

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of U.S. Ser. No. 16/787,102, filed Feb. 11, 2020, which claims the benefit of U.S. Provisional Patent Application No. 62/804,984, filed Feb. 13, 2019, the entire contents of which are hereby incorporated by reference. 
    
    
     BACKGROUND 
     A layboy is a conveyor that may be mounted at the discharge side of a rotary die cut machine for receiving one or more streams of sheets or blanks produced by the rotary die cut machine. The layboy has an upper belt section comprising a plurality of rotatable belts extending in a sheet transport direction and a lower belt section comprising a plurality of rotatable belts extending in the sheet transport direction. A sheet transport path is defined between the bottoms of the upper belts and the tops of the lower belts. Blanks output by the rotary die cut machine enter an upstream end of the layboy at a series of entry nips defined by pairs of the upper and lower belts, are transported along the sheet transport path by the moving upper and lower belts and are discharged from a discharge end of the layboy. 
     A conventional rotary die cut machine cuts finished blanks from sheets of material that are input to the machine. Scrap is produced during this process which consists mainly of the portion of the input material that does not become part of a finished blank. In addition, each blank may include slots or through-openings. The material cut from the input material to form these slots and through-openings also constitutes scrap. 
     Most scrap drops beneath or immediately downstream of the die cut machine as it operates. However scrap, especially small, lightweight pieces of scrap, may be ejected from the die cut machine in such a manner that it falls into the layboy section from above or is drawn into the intake end of the layboy section either alone or along with the blanks. Excessive scrap in the transport path from the die cut machine to the final stack of blanks may adversely affect the transport of the blanks. That is, the scrap may interfere with the alignment of the blanks or lead to jams. Alternately, if the scrap is carried all the way through the transport path and into the final stack of blanks, the blanks in the stack will have gaps therebetween where the scrap material is present thus resulting in a crooked, or oversized or non-uniform stack of blanks. It would therefore be desirable to eliminate or at least reduce the amount scrap material in the transport path of a layboy. 
     SUMMARY 
     This problem and others are addressed by embodiments of the present disclosure, a first aspect of which comprises a layboy having an upstream end, a downstream end spaced from the upstream end in a longitudinal direction, an upper belt section and a lower belt section. The upper belt section includes a plurality of transversely spaced upper belts extending in the longitudinal direction from the upstream end to the downstream end, each of the upper belts having a bottom defining an upper boundary of a transport path through the layboy. The lower belt section includes a plurality of transversely spaced lower belts extending in the longitudinal direction from the upstream end to the downstream end, each of the lower belts having a top defining a lower boundary of the transport path. The bottom of at least one of the upper belts includes a first portion extending from the upstream end to a first diversion guide, a second portion extending from the downstream end to a second diversion guide, a diverted portion between the first diversion guide and the second diversion guide at which the bottom of the at least one of the upper belts extends from the first diversion guide to a third diversion guide offset from the transport path and from the third diversion guide to the second diversion guide such that the diverted portion of the belt is spaced from the transport path. In addition or in the alternative, the top of at least one of the lower belts includes a first portion extending from the upstream end to a first diversion guide, a second portion extending from the downstream end to a second diversion guide, a diverted portion between the first diversion guide and the second diversion guide at which the top of the at least one of the lower belts extends from the first diversion guide to a third diversion guide offset from the transport path and from the third diversion guide to the second diversion guide such that the diverted portion of the belt is spaced from the transport path. 
     A layboy according to another aspect of the disclosure has an upstream end, a downstream end spaced from the upstream end in a longitudinal direction, an upper belt section and a lower belt section. The upper belt section includes a plurality of transversely spaced upper belts extending in the longitudinal direction, bottom portions of the plurality of upper belts lying in a first plane defining an upper boundary of a transport path from the upstream end to the downstream end. The lower belt section includes a plurality of transversely spaced lower belts extending in the longitudinal direction, top portions of the lower belts lying in a second plane defining an upper boundary of the transport path. The bottom portion of at least one of the upper belts extends away from the first plane and away from the second plane to define one side of a gap in the upper boundary of the transport path, and/or the top portion of at least one of the lower belts extends away from the first plane and away from the second plane to define one side of a gap in the lower boundary of the transport path. 
     A further aspect of the disclosure comprises a layboy having an upstream end, a downstream end spaced from the upstream end in a longitudinal direction, an upper belt section and a lower belt section. The upper belt section includes a plurality of upper arms, each of the upper arms having an upstream belt support at the upstream end and a downstream belt support at the downstream end and an upper belt supported by and extending around the upstream belt support and downstream belt support, the upper belt having a bottom portion defining an upper boundary of a transport path through the layboy. The lower belt section includes a plurality of lower arms, each of the lower arms including an upstream belt support at the upstream end of the lower arm and a downstream belt support at the downstream end of the lower arm and a lower belt supported by and extending around the upstream belt support on the lower arm and the downstream belt support on the lower arm, the lower belt having a top portion defining a lower boundary of the transport path. A support member depends from one of the upper arms and includes a first diversion guide, a second diversion guide and a third diversion guide, wherein the upper belt extends from the upstream belt support to the first diversion guide, the third diversion guide, the second diversion guide and the downstream belt support, in order, and wherein the third diversion guide is offset from the transport path such that a gap in the transport path is formed between the first diversion guide and the second diversion guide. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These features will be better understood after a reading of the following detailed description in connection with the attached drawings, wherein: 
         FIG.  1    is a perspective view of a layboy according to a first embodiment of the present disclosure which layboy includes a plurality of lower arms supporting lower belts and a plurality of upper arms supporting upper belts which upper belts include diverted portions. 
         FIG.  2    is a left side elevational view of an upper arm and an lower arm of the layboy of  FIG.  1   . 
         FIG.  3    is a bottom perspective view of the upper arms of the layboy of  FIG.  1   . 
         FIG.  4    is a bottom perspective view of a set of upper layboy arms according to a variation of the first embodiment of the disclosure. 
         FIG.  5    is a left side elevational view of upper and lower layboy arms of a second embodiment of the present disclosure in which the upper layboy arm supports an upper belt and the lower layboy arm supports a lower belt which lower belt includes a diverted portion. 
         FIG.  6    is a left side elevational view of an upper layboy arm supporting an upper belt and a lower layboy arm supporting a lower belt according to a third embodiment of the disclosure in which the upper and lower belts include transversely aligned diverted portions. 
         FIG.  7    is a left side elevational view of an upper layboy arm supporting an upper belt and a lower layboy arm supporting a lower belt according to a variation of the third embodiment of the disclosure in which the upper and lower belts include transversely offset diverted portions. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the drawings, wherein the showings are for the purpose of illustrating preferred embodiments of the disclosure only and not for the purpose of limiting same,  FIG.  1    shows a layboy  10  having an input end  12 , a discharge end  14 , a left side  16  and a right side  18 . Blanks of material (not illustrated) are received at the input end  12 , from the output of a rotary die cut machine (not illustrated), for example, and travel in a direction toward the discharge end  14  which direction may be referred to herein as a “sheet transport direction” or a “longitudinal direction.” The direction perpendicular to the longitudinal direction from the left side  16  to the right side  18  may be referred to as a “transverse direction.” The direction perpendicular to both the longitudinal direction and the transverse direction may be referred to as the vertical or up-down direction. 
     The layboy  10  has an upper belt section  20  that includes a plurality of upper arms  22  (eight in this embodiment) each of which includes an upstream belt support wheel  24  at the input end  12  of the layboy  10  and a downstream belt support wheel  26  (visible in  FIG.  2   ) at the discharge end  14  of the layboy  10  and an upper belt  28  mounted on and extending between the upstream and downstream belt support wheels  24 ,  26 . The layboy further has a lower belt section  30  including a plurality of lower arms  32  disposed beneath the upper arms  22 , an upstream belt support wheel  34  at the input end  12  of the layboy  10 , a downstream belt support wheel  36  at the discharge end  14  of the layboy and a lower belt  38  mounted on and extending between the upstream and downstream belt support wheels  34 ,  36 . 
     In the present embodiment, the upper belts  28  and the lower belts  38  have a substantially circular cross section, and the belt support wheels  24 ,  26  of the upper belt section  20  and the belt support wheels  34 ,  36  of the lower belt section  30  comprise flanged wheels or pulleys configured to guide these round belts. However, different belts, for example flat band-shaped belts, belts having a non-circular and/or variable cross section or V-shaped belts, could also be used on the layboy  10 , and in such case the belt support wheels could be configured as, without limitation, flat rollers, sprockets or flanged wheels having a configuration adapted to the different belt shapes. All such rotatable belt supports are intended to be covered by the phase “belt support wheel” as used herein. 
     The downstream upper belt support wheels  26  are each mounted on a first driven shaft  40  that is operably connected to and driven by a drive  42  such as an electric motor. The upstream upper belt support wheels  24  are mounted at the ends of upper extension arms  44  and are not interconnected; they may thus rotate independently of each other, at least when not connected to the downstream upper belt support wheels  26  by an upper belt  28 . The downstream lower belt support wheels  36  are mounted on a second driven shaft  46  that is operably connected to the drive  42  either directly or via the first driven shaft  40 . The upstream lower belt support wheels  34  are mounted at the ends of lower extension arms  48  and are not interconnected; they are thus free to rotate independently of each other, at least when not connected to the downstream lower belt support wheels  36  by the lower belts  38 . 
     An upstream guide arm  50  supporting a first upper guide wheel  52  and a downstream guide arm  54  supporting a second upper guide wheel  56  depend from the upper arm  22 . The first and second guide wheels  52 ,  56  guide the bottom portion  58  of the upper belt  28  along a first plane spaced from the bottom edges of the upper support wheels  24 ,  26 . The first upper guide wheel  52  helps to create an input nip  60  at the input end  12  of the layboy  10 , and the second upper guide wheel  56  creates a discharge spacing  62  at the discharge end  14  of the layboy  10 . The layboy lower arms  32  include a downstream guide arm  64  that supports a downstream guide wheel  66  to maintain a top portion  68  of the lower belt  38  in a second plane, spaced from the first plane. The bottom portions  58  of the upper belts  28  and the top portions  68  of the lower belts  38  define between them a transport path  70  for sheets of material carried through the layboy  10 . 
     A mounting plate  72  depends from at least one of the upper arms  22  at a location between the upstream guide arm  50  and the downstream guide arm  54  and includes three diversion guides for diverting the upper belt  28  away from the first plane and away from the transport path  70  and then returning the upper belt  28  to the transport path  70 . These include a first diversion guide  74  at the transport path  70 , a second diversion guide  76  directly above the first diversion guide  74 , and a third diversion guide  78  at the transport path  70  downstream from the first diversion guide  74 . In the disclosed embodiment, the diversion guides  74 ,  76 ,  78  are flanged wheels configured to guide the round upper belts  28 , but different diversion guides adapted to different types of belt could be used. The bottom  58  of the upper belt  28  thus extends from the upper upstream belt support wheel  24  past the first upper guide wheel  52  to the first diversion guide  74 . The portion of the bottom  58  of the upper belt  28  from the first upper guide wheel  52  to the first diversion guide  74  may be referred to as a “first portion” or “upstream portion” of the bottom  58  of the upper belt  28 . The upper belt  28  then passes around the downstream side of the first diversion guide  74  and turns approximately 90 degrees away from the first plane and follows an S-shaped path around the second diversion guide  76 . The upper belt  28  leaves the second diversion guide  76  and heads toward the third diversion guide  78  at an angle and returns to the first plane and to the transport path  70  at the third diversion guide  78 . The portion of the bottom  58  of the upper belt  28  between the first diversion guide  74  and the third diversion guide  78  may be referred to as the “third portion” or the “diverted portion” of the bottom portion  58  of the upper belt  28 . The portion of the bottom  58  of the upper belt  28  between the third diversion guide  78  and the second upper guide wheel  56  may be referred to as the “second portion” or “downstream portion” of the bottom  58  of the upper belt  28 . 
     Diverting the portion of the bottom  58  of the upper belt  22  between the first diversion guide  74  and the third diversion guide  78  creates a gap in the transport path, that is, a region where the upper belt  28  moves away from the transport path  70 , so that blanks being transported through the layboy  10  belt are not in contact with the upper belt  28  in this diverted portion of the path. This “gap” in the transport path allows scrap material that may have entered the layboy and come to be trapped between an upper belt  28  and the top of a blank to fall or be dislodged from the blank. This reduces the likelihood that the scrap will be discharged from the layboy  10  at the discharge end  14 . The removal of scrap may be aided by the presence of a fan (not illustrated) at the side of the layboy for creating an airflow inside or through the layboy  10 . Significantly, the gap, or the distance between the first diversion guide  74  and the third diversion guide  78 , is shorter than the length of the shortest blanks that will be conveyed through the layboy  10  so that at least part of each blank is always in contact with the upper belt  28 . 
     The diversion guides  74 ,  76 ,  78  are preferably provided on each of the upper arms  22  to form gaps in each of the upper belts  28 . The gaps can be transversely aligned, as shown in the bottom plan view of the upper arms  22  in  FIG.  3   , or, in the alternative, the gaps can be staggered or offset in the transverse direction as illustrated in  FIG.  4    which shows an upper arm section  20 ′. When the gaps are aligned, long pieces of scrap that extends across multiple belts  28  may be more easily dislodged; staggering the gaps as illustrated in  FIG.  4   , on the other hand, may provide better control over the movement of the blanks through the layboy  10  under certain conditions. 
     A second embodiment of the disclosure is illustrated in  FIG.  5   . Elements identical to those of the first embodiment are identified with like reference numerals, and only the differences between the first and second embodiments are described. As will be appreciated from  FIG.  5   , the upper belt section  20  of the second embodiment is substantially identical to the upper belt section  20  of the first embodiment except that the upper arms  22  do not include a mounting plate  72  with first, second and third diversion guides  74 ,  76 ,  78 . Instead, the lower arms  32  of the lower arm section  30 ′ are provided with an upwardly extending mounting plate  82 , a first diversion guide  84 , a second diversion  86  and a third diversion guide  88  for diverting portions of the tops  68  of the lower belts  32  away from the transport path. In this embodiment, the “gap” in the transport path  70  is formed in the lower belts  32  which gap allows any scrap trapped between a bottom side of a blank and the tops  68  of the lower belts  38  to fall away from the transport path  70 . 
     A third embodiment is illustrated in  FIG.  6   . In this embodiment, the upper arms  22  of the upper arm section  20  includes the mounting plates  72  of the first embodiment with the first, second and third diversion guides  74 ,  76 ,  78  mounted thereon for diverting a portion of the bottoms  58  of the upper belts  28  away from the transport path, and the lower arms  32  of the lower arm section  30 ″ include the mounting plates  82  of the second embodiment with the first, second and third diversion guides  84 ,  86 ,  88  mounted thereon for diverting a portion of the tops  68  of the lower belts  38  from the transport path  70 . In this embodiment, the gaps in the upper belts  28  and in the lower belts  38  are transversely aligned. 
     The fourth embodiment of the disclosure illustrated in  FIG.  7    is identical to the third embodiment except that the mounting plates  72  of the upper arms  22  of the upper arm section  20  and the mounting plates  82  of the lower arms  32  of the lower arm section  30 ′″ are longitudinally offset so that, for example, the leading edge of each of the blanks being transported is always in contact with one of the upper and lower belts  28 ,  38  as they pass through the layboy  10  while still allowing scrap to be removed from the upper and lower surfaces of the blanks. 
     The present invention has been described herein in terms of several embodiments. Modifications and additions to these embodiments will become apparent to persons of ordinary skill in the relevant arts upon a reading of the foregoing description. It is intended that all such modifications and additions comprise a part of the present invention to the extent they fall within the scope of the several claims appended hereto.