Patent Publication Number: US-2009239726-A1

Title: System and apparatus for erecting cases

Description:
TECHNICAL FIELD 
     The present application relates to systems and apparatus for erecting cases and a stabilizer bar system for use with same. 
     BACKGROUND 
     In the erecting of a carton or case from a knocked down blank, the knocked down carton or case is opened do that adjacent sides form a right angle and then the bottom flaps folded into closed position. The erecting operation generally withdraws a single knocked down case blank from a magazine of such blanks held in face to face position, opens the flat blank from the knocked down condition into a square-corner condition wherein adjacent side walls of the case are generally mutually perpendicular and positions the erected blank into a bottom flap folding station. In the bottom flap folding station, the minor flaps (generally the shorter flaps), one connected to each of the leading and trailing side panels of the case (oriented in the direction of travel of the case from the erecting station), are folded relative to their respective side panels and then the major flaps one connected to each of the remaining side wall (walls parallel to the direction of travel) are folded into underlining relation (outwardly exposed relation) to the minor flaps. 
     The erected case is then moved into a bottom closure station, which may be a taping station where a tape or adhesive is applied along the bottom major flaps extending in the direction of travel of the case through the taping station to secure the major flaps in folded closed position and thereby the case in erected condition with the adjacent side panels mutually perpendicular. In this condition, the top closing flaps are generally open so that the case may be filled and then the top flaps are closed and secured in closed position for example by taping or adhesive similar to the bottom taping operation to complete the erecting filling and closing cycle and the filed box is ready for shipment. 
     SUMMARY 
     In an aspect, a case forming apparatus that erects cases from knocked-down case blanks includes a first jaw and a plurality of stabilizer bars each having a first end mounted to the first jaw. The stabilizer bars are spaced radially from each other and form concentric segments of circles centered on a pivotal axis. A moveable second jaw is mounted for movement on the pivotal axis relative to the first jaw between an open position where the moveable second jaw is substantially perpendicular to the first jaw and a closed position where the moveable second jaw is substantially parallel to the first jaw. The moveable second jaw includes openings through which the stabilizer bars pass as the moveable second jaw moves between the open and closed positions. One or more of the stabilizer bars has a cross-sectional width that varies over at least one-third of a cross-sectional height of the at least one stabilizer bar. 
     In another aspect, a case forming apparatus that erects cases from knocked-down case blanks includes a first jaw and a plurality of stabilizer bars each having a first end mounted to the first jaw. The stabilizer bars are spaced radially from each other and form concentric segments of circles centered on a pivotal axis. A moveable second jaw is mounted for movement on the pivotal axis relative to the first jaw between an open position where the moveable second jaw is substantially perpendicular to the first jaw and a closed position where the moveable second jaw is substantially parallel to the first jaw. The moveable second jaw includes openings through which the stabilizer bars pass as the moveable second jaw moves between the open and closed positions. At least one of the stabilizer bars includes an intermediate portion with a cross-sectional surface area that is less than that of the first end. 
     In another aspect, a case forming apparatus that erects cases from knocked-down case blanks includes a first jaw and a plurality of stabilizer bars each having a first end mounted to the first jaw. The stabilizer bars are spaced radially from each other and form concentric segments of circles centered on a pivotal axis. A moveable second jaw is mounted for movement on the pivotal axis relative to the first jaw between an open position where the moveable second jaw is substantially perpendicular to the first jaw and a closed position where the moveable second jaw is substantially parallel to the first jaw. The moveable second jaw includes openings through which the stabilizer bars pass as the moveable second jaw moves between the open and closed positions. A support member includes a lift mechanism for changing an elevation of the moveable second jaw and the first jaw, the first jaw being mounted directly to the support member. A support beam is mounted directly to the support member wherein a second end of each stabilizer bar is mounted to the support beam. 
     The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of a case forming apparatus; 
         FIGS. 2 and 3  are perspective views of an embodiment of a case erecting system for use in the case forming apparatus in open and closed positions, respectively; 
         FIG. 4  is a top view of an embodiment of a stabilizer bar for use with the case erecting system of  FIGS. 2 and 3 ; 
         FIGS. 5 and 6  are detail views of opposite ends of the stabilizer bar of  FIG. 4 ; 
         FIG. 7  is a section view of multiple stabilizer bars including the stabilizer bar of  FIG. 4  along line  7 - 7 ; 
         FIG. 8  is a section view of another embodiment of a stabilizer bar; and 
         FIG. 9  is a section view of another embodiment of a stabilizer bar. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , an apparatus  10  for erecting and sealing a case  12  includes a magazine  14  holding a number of knocked-down case blanks  16 . The case blanks  16  are extracted from the magazine  14  and squared using an erecting system  18 . The erecting system  18  includes a jaw assembly  19  including a pair of jaws  20  and  22 , where jaw  20  is moveable and jaw  22  is fixed (relative to the jaw assembly). The moveable jaw  20  is pivoted using a suitable drive mechanism as represented and indicated by arrow  24  on a pivotal axis or hinge  26  between a pick-up or gripping position where the jaws  20  and  22  are in an opposed, substantially parallel relationship and open position where the jaws are in a substantially perpendicular relationship. 
     The moveable jaw  20  and fixed jaw  22  are also moveable vertically along a track member  27  by a lift mechanism carriage or traveler  28  that moves the jaw assembly  19  as indicated by arrow  30 . The fixed and moveable jaws  20  and  22  receive a knocked-down case blank  16  with the jaws in their closed or pick-up position (as shown in  FIG. 3 ) and move the case blank  16  from the magazine  14 . The moveable jaw  20  is then moved relative to the fixed jaw  22  to the position illustrated (i.e., the open position as also shown in  FIG. 2 ) to open the blank into a square-corner condition (now indicated by element  32 ). The erected case  32  is then moved downward as indicated by arrow  30  into the bottom flap folding station  34 . 
     The erected case  32  has a leading wall panel  36  (leading in the direction of movement of the case through the apparatus  10 ) to which are connected a leading bottom flap  38  and a leading top flap  40 . The erected case  32  has a corresponding trailing wall panel  42  with a trailing bottom flap  44  and a trailing top flap  46 . The leading and trailing wall panels  36  and  42  are connected by a pair of opposed side wall panels  48  and  50 , each with a side bottom flap  52 ,  54  and a side top flap  56 ,  58 . The shorter leading and trailing wall panels  36  and  42  and flaps  38 ,  40 ,  44  and  46  are generally referred to as minor side walls and flaps and the longer side wall panels  48  and  50  and flaps  52 ,  54 ,  56  and  58  are generally referred to a major wall panels and flaps. The major wall panels and flaps  48 ,  50 ,  52 ,  54 ,  56  and  58  may, but not necessarily, be oriented parallel to the direction of travel, e.g., so that the major flaps are folded last and exposed as the erected case  32  is moved into a bottom sealing station  60 . 
     The folding station  34  is provided with flap folding equipment for folding the leading bottom minor flap  38  and the trailing bottom minor flap  44 . The folding station  34  folds the leading and trailing bottom flaps  38  and  44  to positions substantially perpendicular to their corresponding leading and trailing wall panels  36  and  42  as the case is moved in the machine direction. The major bottom flaps  52  and  54  are then folded substantially perpendicular to their corresponding side wall panels  48  and  50 . 
     The erected case  32  with its bottom flaps  38 ,  44 ,  52  and  54  folded is then advanced into and through the bottom sealing station  60  by any suitable mechanism, in the illustrated embodiment, a pusher mechanism  62 . 
     Referring now to  FIGS. 2 and 3 , components of the erecting system  18  including the jaws  20  and  22  of jaw assembly  19  are illustrated in greater detail.  FIG. 2  illustrates the moveable and fixed jaws  20  and  22  in their open position and  FIG. 3  illustrates the moveable and fixed jaws in their closed positions. The fixed and moveable jaws  22  and  20  are mounted to a support member  69 . The support member  69  includes the lift mechanism traveler  28  that rides along the track member  27  ( FIG. 1 ). Stabilizer bars  64 ,  66  and  68  are mounted in fixed relation to the fixed jaw  22  as indicated at  70 ,  72  and  74 . The stabilizer bars  64 ,  66  and  68  form quadrants of concentric circles indicated by the radii r 1 , r 2  and r 3 , respectively ( FIG. 2 ) centered on the hinged or pivotal axis  26  about which the moveable jaw  20  is pivoted. An actuator  76  (e.g., a pneumatic cylinder) is used to pivot the moveable jaw  20  about the pivotal axis  26 . 
     Gripping pins  78 , such as those described in U.S. Pat. Nos. 4,553,954, 7,192,393 and 7,316,643, are positioned adjacent to and between the mountings  70 ,  72  and  74  of the stabilizer bars  64 ,  66  and  68  on the fixed jaw  22 . Similar gripping pins  78  are provided on the moveable jaw  20 , but are positioned on the opposite side of their respective adjacent stabilizer bar  64 ,  66 ,  68  as compared to the gripping pins on the fixed jaw  22 . The gripping pins  78  are placed in this staggered relationship so that they do not collide together and interfere with the closing of the jaws  20  and  22 . 
     The stabilizer bars  64 ,  66  and  68  pass through respective openings  80 ,  82  and  84  in the moveable jaw  20 . As shown by  FIG. 3 , panels  86  and  88  are located above and below the stabilizer bars  64 ,  66  and  68  and mounted to the moveable jaw  20 . The panels  86  and  88  are made of a material that facilitate movement of the moveable jaw  20  along the stabilizer bars  64 ,  66  and  68  should the stabilizer bars contact the panels. 
     As indicated above, the stabilizer bars  64 ,  66  and  68  are mounted at one end to the fixed jaw  22 . The fixed jaw  22  is, in turn, mounted to the support member  69 . The other end of the stabilizer bars  64 ,  66  and  68  is mounted to a rigid support beam  90  ( FIG. 3 ). The rigid support beam  90  is, in turn, mounted to the support member  69  so that both ends of the stabilizer bars  64 ,  66  and  68  are connected to the support member. In other words, the ends of the stabilizer bars  64 ,  66  and  68  opposite the fixed jaw  22  are not free hanging, unconnected to the support member  69 . In addition to supporting the ends of the stabilizer bars  64 ,  66  and  68  opposite the fixed jaw  22 , the support beam  90  interconnects the stabilizer bars, which maintains spacing between the ends. 
       FIG. 4  shows one of the stabilizer bars  64 ,  66  or  68  in isolation. While only one stabilizer bar is described in detail, each stabilizer bar has a similar construction. The stabilizer bar  64 ,  66  or  68  includes the end  92  ( FIG. 5 ) that is mounted to the fixed jaw  22  and the end  94  ( FIG. 6 ) that is mounted to the support beam  90 . While any suitable mounting may be used, threaded fasteners are inserted into threaded openings  96  located at each end  92  and  94  to mount the ends to the fixed jaw  22  and the support beam  90 . As can be seen, end  92  is wider in dimension than end  94 . The wider end  92  also provides a larger connection point to the fixed jaw  22  to accommodate the mounting fasteners and provide increase strength where forces on the stabilizer bars are the greatest. End  92  tapers down to a narrower width that is substantially constant along the remaining length (e.g., about 70 degrees of arcuate length) of the stabilizer bar  64 ,  66  or  68 . 
       FIG. 7  illustrates a section view (see  FIG. 4 ) of each stabilizer bar  64 ,  66  and  68 . The stabilizer bars  64 ,  66  and  68  have essentially the same cross-sectional shape along the majority of their lengths. Each stabilizer bar  64 ,  66  and  68  includes a mid section  98  having a greatest width and upper and lower tapered sections  100  and  102  that taper in width to upper and lower surfaces  104  and  106 . A width of each stabilizer bar  64 ,  66  and  68  varies over at least one-third (e.g., two-thirds) of a height H of each stabilizer bar with the width of the mid section  98  remaining substantially constant. Thus, each stabilizer bar  64 ,  66  and  68  has a cross-sectional area A that is less than an imaginary rectangle (represented by dashed line  108 ) bounded by the upper surface  104 , the lower surface  106  and side surfaces  110  and  112 . 
     Referring also to  FIG. 1 , the lower surfaces  106  of the stabilizer bars  64 ,  66  and  68  are arranged in a common radial plane and are positioned to engage top edges of the upper flaps  40  and  56  adjacent to a free corner  114  of the erected case  32  so that this corner is positioned at a same elevation as an opposite corner of the erected case when the case is forced down into the bottom folding station  34 . Contact between the bottom flaps with elements of the bottom folding station  34  will not move the erected case upward past the radial plane, which could distort the completed case. 
     Providing the cross-sectional arrangement for the stabilizer bars  64 ,  66  and  68  shown in  FIG. 7  limits the surface  106  in contact with top edges of the front minor flap  40  and side major flap  46  of the case  32  as shown in  FIG. 1 . Should there be a collision of the bottom case flaps  38 ,  44 ,  52  and/or  54  with the bottom folding station  34  (e.g., due to improper adjustment or other reasons), the stabilizer bars  64 ,  66  and  68  will act as dull knives and cut into or crush the corrugated paperboard material of the case rather than be unduly deformed by the upward forces caused by the collision. In some embodiments, various dimensions of the surface  106  may be selected based on characteristics of the paperboard material used to form the cases  32 . Upper surface  104  is substantially the same dimension as the lower surface  106  as some cases require opening in an opposite hand direction to that shown by  FIG. 1 . In these embodiments, an alternative mirror image mechanism is used where the stabilizer bars  64 ,  66  and  68  are mounted upside down relative to the positions shown in  FIGS. 1-3 . The bar width W at the center between surfaces  110  and  112  is greater than that at the upper and lower surfaces  104  and  106  to provide greater strength and rigidity of the bars with minimum weight overall compared to rectangular section bars. 
     The erected case  32  is relatively large and its free corner  114  engages or is located nearest the largest radius stabilizer bar  68 . For smaller cases, the other stabilizer bars  64  or  66  may contact or be nearest the free corner of the case. Thus, a number or range of case sizes may be erected without requiring substantial modification of the equipment thereby significantly decreasing downtime when the case size being erected is changed significantly. 
     Various adjustment systems may be used to adjust various elements of the apparatus  10 . For example, the positions of the moveable and fixed jaws  20  and  22  may be adjusted relative to each other. In some embodiment, an adjustment system may be provided to adjust the size of a gap G between the moveable and fixed jaws  20  and  22  when in the closed position (see  FIG. 3 ). 
     It is to be clearly understood that the above description is intended by way of illustration and example only and is not intended to be taken by way of limitation, and that changes and modifications are possible. For example, other cross-sections for the stabilizer bars may be used.  FIG. 8  shows an alternative embodiment where upper and lower sections  116  and  118  of stabilizer bar  120  taper inwardly from top and bottom surfaces  122  and  124  toward the middle.  FIG. 9  shows another stabilizer bar embodiment  126  having curved sections  128  and  130 . Accordingly, other embodiments are within the scope of the following claims.