Abstract:
A case forming machine for erecting cases from knock down case form to an open form and move an opened case downward to bottom forming station using a fixed and a moveable jaw system is improved by providing a plurality of radially spaced, concentric stabilizer bars fixed to the fixed jaw and arranged to form concentric segments of circles centered on pivotal axis of the moveable jaw and having their bottom edges in a radial plane relative to said pivotal axis. Also provided is a micrometer type adjustment mechanism that is used for adjusting the gap between said fixed and moveable jaws when said jaws are in said parallel pick-up position.

Description:
FIELD OF INVENTION  
       [0001]     The present invention relates to a carton or case erector for squaring and erecting a case. More particularly the present invention relates to an improved case stabilizer system capable of stabilizing different sized cases as they are being erected. The present invention also relates to an improved case thickness adjusting system for the erector  
       BACKGROUND OF THE PRESENT INVENTION  
       [0002]     In the manufacture (erection and taping of flaps to produce a carton or case from a knocked down blank) the knocked down carton or case is first squared and then the bottom flaps folded into closed position. The squaring operation generally withdraws a singe knocked down case blank from a magazine of such blanks held in face to face position, opens the blank from the knocked down condition into a squared condition wherein adjacent side walls of the case are generally mutually perpendicular and positions the squared 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 so erected case is then moved into a bottom closure station which may be 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 squared condition with the adjacent side panels mutually perpendicular. In this condition the top closing flaps are generally in open position 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.  
         [0003]     U.S. Pat. No. 5,553,954 issued Nov. 10, 1985 to Sewell et al. describes the erector to which the present invention is a significant improvement and the disclosure of this patent is incorporated herein by reference. This patent teaches the use of relatively pivoting jaws a fixed jaw oriented perpendicular to the direction of travel of a case through the erector i.e. from a bottom erector station and a moveable jaw that pivots on a pivotal axis between a pick-up or gripping position with the moveable jaw substantially parallel to and spaced from the fixed jaw to a position perpendicular to the fixed jaw. These erectors normally are designed to erect case blanks having significantly different thicknesses so the erector is normally made so that the spacing between the moveable and fixed jaws in the parallel position is adjustable to accommodate knocked down case blanks of different thicknesses. This is accomplished in the prior art by moving the fixed jaw.  
         [0004]     The jaws grip the top flaps extending from of a pair of adjacent side panels of a case and open (square) the case by pivoting the moveable jaw on the pivotal axis. These jaws in their mutually perpendicular position (open or squaring position) then move the so opened (squared) case down into the bottom erecting station wherein bottom flaps are folded as above described.  
         [0005]     In the prior art system a single substantially circular stabilizer bar is removably mounted on the fixed jaw and extends in an arc centered on the pivot axis or hinge point between the jaws and passes through suitable opening in the moveable jaw (to permit the relative movement of the moveable jaw between parallel (pick-up) and open (squaring) position). The stabilizer bar is positioned with its bottom edge in position to contact with to top edges of the other major and minor top flaps adjacent to the free corner (corner remote from the pivotal axis) of the case to keep the case in proper orientation i.e. stop the free corner of the case from moving upward as the case is moved into the bottom forming station. The stabilizer bar must be moveably mounted to accommodate different sized cases i.e. cases having their free corner spaced from the pivotal axis by significantly different lengths and the above described thickness adjustment (change in the space between the fixed and moveable jaws in the parallel pick-up or gripping position) to position the stabilizer bar in a position whereby it will pass through holes in the moveable jaw positioned between adjacent grippers.  
         [0006]     In the prior art machine wherein the stabilizer bar position required adjustment when significantly different sized boxes or cases were to be erected the spacing between the jaws in the parallel pick up position which also had to be changed when knocked down blanks for cases of significantly different thickness were to be erected, was adjusted by physically moving the fixed jaw. Movement of the fixed jaw requires unbolting the fixed jaw, moving it and bolting it back in position which also required in many cases that the separator bar that moves the lead blank down from the magazine (see U.S. Pat. No. 5,553,954) required adjustment to be properly positioned relative to the fixed jaw in its new position. These procedures required a significant amount of time and skill to ready the machine to process blanks of the new (different) thickness.  
       BRIEF DESCRIPTION OF THE PRESENT INVENTION  
       [0007]     It is the main object of the present invention to provide an improved stabilizer system requiring no adjustment to accommodate different sized cases.  
         [0008]     It is a further object of the present invention to provide a simplified and easier operated adjustment system for accommodating knocked down cases of different thicknesses.  
         [0009]     Broadly the present invention relates to a case forming machine for erecting cases from knock down case form to an open form and move an opened case downward to bottom forming station comprising a fixed jaw and a moveable jaw mounted for movement on a pivotal axis between a pick-up position wherein said fixed and moveable jaws are substantially parallel and an open squaring position wherein said fixed and moveable jaws are substantially perpendicular, a plurality of radially spaced, concentric stabilizer bars fixed adjacent to one end to said fixed jaw and arranged to form concentric segments of circles centered on said pivotal axis, passages through said moveable jaw positioned to permit said bars to pass through said moveable jaw as said moveable jaw is moved between said pick-up and open positions, said bars having their bottom edges in a radial plane relative to said pivotal axis.  
         [0010]     Preferably an interconnecting bar interconnects said bars on the side of said moveable jaw remote from said fixed jaw.  
         [0011]     Preferably said bars have essentially the same cross sectional shape and a width measured in a direction radial to said pivotal axis significantly less than the height of said bars measured parallel to said pivotal axis.  
         [0012]     Preferably said moveable jaw is mounted on an adjustment mechanism that adjusts the position of said moveable jaw so that the gap between said moveable and said adjustable jaw in said parallel pick-up position is changed.  
         [0013]     Broadly the present invention also relates to a case forming machine for erecting cases from knock down case form to an open form and move an opened case downward to bottom forming station comprising a fixed jaw and a moveable jaw mounted for movement on a pivotal axis between a pick-up position wherein said fixed and moveable jaws are substantially parallel and an open squaring position wherein said fixed and moveable jaws are substantially perpendicular, the improvement comprising an adjustment mechanism having a mounting portion and an adjustment portion, said mounting portion mounted for pivotal movement on said pivotal axis and said adjustment portion being moveable relative to said mounting portion in a direction substantially parallel to said fixed jaw when said moveable jaw is in said open squaring position and means to move said adjusting portion relative to said mounting portion thereby adjusting the gap between said fixed and moveable jaws when said jaws are in said parallel pick-up position.  
         [0014]     Preferably said means to move comprises a manually operable micrometer type adjustment system.  
         [0015]     Preferably a stop damper mounted in a fixed position relative to fixed jaw dampens movement of said moveable jaw as it approaches said open perpendicular position and stops said moveable jaw in said open perpendicular position.  
         [0016]     Preferably a second stop damper mounted in a fixed position relative to fixed jaw dampens movement of said moveable jaw as it approaches said parallel pick-up position and stops said moveable jaw in said parallel pick-up position. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0017]     Further features, objects and advantages will be evident from the following detailed description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings in which;  
         [0018]      FIG. 1  is a schematic isometric illustration of the operation of a typical erector with present invention in place and illustrating the operation of the erector.  
         [0019]      FIG. 2  is an isometric view with parts omitted for clarity of the opening jaws in parallel pick-up position with the stabilizer bars of this invention in position.  
         [0020]      FIG. 3  is a section along the line  3 - 3  of  FIG. 2   
         [0021]      FIG. 4  is an isometric view with parts omitted for clarity similar to  FIG. 2  but with the jaws in open squaring position i.e. with the jaws perpendicular to each other.  
         [0022]      FIG. 5  is a view with parts removed for clarity showing the jaws in their substantially parallel pick-up position and parts of the micrometer gap adjustment mechanism for adjusting the gap between the jaws in the parallel pick-up position to accommodate knocked down case blanks of different thickness.  
         [0023]      FIG. 6  is a plan view of the jaws in the pick-up position. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0024]      FIG. 1  illustrates a typical application of the present invention and particularly showing the invention applied to an erector of type described in U.S. Pat. No. 4,553,954 referred to above and incorporated herein by reference.  
         [0025]     The erector and sealer  10  is provided with a magazine  12  containing knocked down box blanks which are extracted and squared by the mechanism  14  which include a moveable jaw  16  and a fixed jaw  18 . The moveable jaw  16  is pivoted by a suitable drive as represented and indicated by arrow  21  on pivotal axis or hinge  20  between a pick-up or gripping position wherein the jaws  16  and  18  are in opposed substantially parallel position (see  FIGS. 2, 5  and  6 ) and a squaring or open position wherein the jaws are substantially mutually perpendicular as shown in  FIGS. 1 and 4 . The fixed and moveable jaws  18  and  16  carrying an open or squared case  24  (squared by movement of the jaw  16  to the perpendicular or squaring position) are then moved vertically by the elevator mechanism schematically indicated at  22  as indicated by the arrow  26 . The jaws in pick-up position (substantially parallel) receive a knocked down blank there between and engage and move same from the magazine as described in U.S. Pat. No. 4,553,954 and as indicated below. The jaws  16  and  18  are then opened to the position illustrated i.e. at a right angle to each other, to square the case  24  which is then moved downward as indicated by the arrow  26  into the bottom flap folding station  28  (see U.S. Pat. No. 4,553,954 and related improvements forming the subject matter of other about to be applied for patents).  
         [0026]     The squared case  24  has a leading wall panel  30  (leading in the direction of movement of the case through the machine  10  from the bottom flap folding station  28  to and through the bottom sealing station  50  which in the illustrated arrangement is a tape applying station (as indicated by the arrow  52 )) to which are connected a leading bottom flap  32  and a leading top flap  34  (see  FIGS. 2 and 4 ). The case  24  has a corresponding trailing wall  36  with corresponding trailing bottom  38  and top  40  trailing flaps. The leading and trailing wall panels  30  and  36  are interconnected by a pair of opposed side wall panels  42  and  44  each with their bottom and top flaps  46  and  48  (the bottom flap  46  connected to side wall  44  is visible in  FIG. 3 ). The shorter leading and trailing sides and flaps are generally referred to as minor side walls or flaps and the longer walls  42  and  44  and their respective bottom and top flaps  46  and  48  are generally called the major side walls or flaps. Generally but not necessarily the major walls and flaps are oriented parallel to the direction of travel  52  which as will be apparent is the direction of tape application in the illustrated bottom taper  50  so the major flaps are folded last and are exposed as the case  24  is moved into the bottom sealing station  50  which is shown as a taping station  50  and the tape is applied to these flaps  46 .  
         [0027]     The folding station  28  is provided with conventional flap folding equipment for folding the leading flap and trailing flaps  32  and  38  fold these flaps  32  and  38  to positions substantially perpendicular to their respective leading and trailing wall panels  30  and  36  as the case  24  is moved down in the direction of the arrows  26 . Next the major bottom flaps  46  are folded substantially perpendicular to their respective side wall panels  42  and  44 . The squared case  24  with its bottom flaps  32 ,  38  and  46  folded is then advanced into and through the bottom sealing station  50  by any suitable mechanism  60  (in the illustrated version a pusher mechanism (subject of U.S. application Ser. No. ______ filed concurrently herewith by Makar et al (WEX5) has been shown).  
         [0028]     As above described in the prior art machines the most relevant of which (to Applicant&#39;s knowledge) is described in U.S. Pat. No. 4,553,954 a single movably mounted stabilizer bar was employed and was moved to the appropriate location when different sized cases were to be erected. This operation required tools and took the operator a significant amount of time to accomplish.  
         [0029]     The present invention overcomes many of the shortcomings of the old system by fixing one end of each of a plurality (3 in the illustrated embodiment shown in FIGS.  1  to  5 ) of stabilizer bars  100 ,  102  and  104  (see particularly  FIGS. 2 and 3  and  4 ) mounted in fixed relation to the fixed jaw  18  as indicated at  106 ,  108  and  110  respectively (see  FIG. 4 ). These bars  100 ,  102  and  104  form quadrants of concentric circles as indicated by the radius r 1 , r 2  and r 3  respectively (see  FIG. 2 ) centered on the hinge or pivotal axis  20  about which the moveable jaw  16  is pivoted when moving between the substantially parallel pick up position (See  FIG. 5 ) and the open or squaring position (see  FIG. 1, 2  or  4 ) wherein the jaws  16  and  18  are mutually perpendicular.  
         [0030]     In the illustrated arrangement gripping pins or pin holders  112  such as those taught in U.S. Pat. No. 5,553,954 but preferably of the type forming the subject matter of application No. filed concurrently herewith by ______ Makar et al (WEX4) are positioned adjacent to and between the mountings  106 ,  108  and  110  of the bars  100 ,  102  and  104  to the jaw  18 . Similar gripping pins or pin holders  114  (see  FIG. 1 ) are provided on the jaw  16  but are positioned on the opposite side of their respective adjacent bar  100 ,  102  or  104  as the pins  112 . The pins or pin holders  112  and  114  are positioned in staggered relationship so that when the jaws  16  and  18  are in the parallel pick-up or gripping position (see  FIGS. 2, 5  and  6 ) the pins or pin holders  112  and  114  do not clash and interfere with the closing of the jaw  16  into the parallel pick-up position relative to the jaw  18 .  
         [0031]     The bars  100 ,  102  and  104  pass through suitably positioned holes  116 ,  118  and  120  respectively through the jaw  16  (see  FIG. 2 ). In the illustrated arrangement a suitable bearing panel  122  with apertures corresponding to the holes  116 ,  118  and  120  through which the bars  100 ,  102  and  104  pass is provided. The bearing panel  122  is made from material that will facilitate relative movement should the bars  100 ,  102  and/or  104  come in contact with the sides of the apertures.  
         [0032]     In the preferred form of the invention a suitable reinforcing bar  123  interconnects the free ends  124 ,  126  and  128  of the bars  100 ,  102  and  104  respectively at the side of the jaw  16  remote from the jaw  18  to maintain the correct spacing between these free ends.  
         [0033]     As illustrated in  FIG. 3  the bars  100 ,  102  and  104  have essentially the same cross sectional shape and a width w measured in a direction radial to the pivotal axis  20  significantly less than the height h of said bars measured parallel to said pivotal axis  20 . As is apparent in  FIGS. 3 and 4  the bottom edges  132 ,  134  and  136  of the bars  100 ,  102  and  104  are in a common radial plane  140  relative to the axis  20  and are positioned to engage the top edges of flaps  34  and  48  adjacent to the free corner  138  of the case  24  (corner remote from the hinge axis  20 ) so that this corner  138  is positioned at the same level as the opposite corner of the case  24  when the case  24  is forced down into the bottom flap folding station  28  i.e. contact of the bottom flaps with elements of the station  28  cannot move the top edges of the flaps  34  and  48  forming the free corner  138  upward past the plane  140  defined by the bottom edges  132 ,  134  and  136  which would distort the box or case  24 .  
         [0034]     In the  FIG. 4  illustration the case  24  is relatively large and its free corner engages the largest radius bar  100 , it will be apparent that when smaller cases are being erected the smaller radius bar  102  or  104  will engage the free corner  138  of the small case and function in the same manner. Thus a plurality or range of box or case sizes may be erected without requiring modification of the equipment thereby significantly decreasing down time when the size of the case being erected is significantly changed.  
         [0035]      FIGS. 5 and 6  show the micrometer adjustment system generally indicated at  200  for changing the gap dimension g (see  FIG. 6 ) defining the gap between the two jaws  16  and  18  when in parallel pick-up position. This gap dimension g is adjusted by manipulating the gap adjustment micrometer type adjustment system  200 .  
         [0036]     The system  200  includes a mounting and bumper plate  202  that is connected to and extends from the hinge having a pivotal axis  20  described above via a mounting block  204 . A mounting and adjustment bar  206  is mounted to side through and be guided by a passage through the plate  202  and is connected to the moveable jaw  16  via the mounting plate  208  which supports the jaw  16  in cantilever fashion. The micrometer adjustment mechanism includes a treaded shaft  210  operated by threads in a corresponding threaded aperture in the block  204  so that turning the knob  212  moves the threaded shaft  210  relative to the block in micrometer type increments. The threaded shaft  210  is connected to an operating arm  214  extending from the block  206  so that movement of the arm  214  imparts like movement to the block  206 . The connection between the arm  214  and the treaded shaft  210  permits substantially free rotation of the shaft  210  while preventing relative axial movement between the shaft  210  and the arm  214  so that axial movement of the shaft  210  is applied to the arm  214  and thereby through the bar  206  and mounting plate  208  to the jaw  16 . Preferably a locking bolt extends from the block  204  through a suitable slot  218  in the bar  206  and is represented by its nut which is in the form of a hand lever  216 . Turning the hand lever nut  216  in one direction releases the bar for axial movement (gap adjustment) and adjustment of the gap g and turning of the lever  216  in the opposite direction forces the bar  206  against the block  204  and locks the bar  206  and thereby the jaw  16  in adjusted position.  
         [0037]     Preferably a suitable damper and stop device  250  having a bumper  252  is mounted in fixed relationship to the fixed jaw  18  and is positioned to be engaged by a portion the plate  202  on the side of the bar  206  remote from the block  204 . The bumper is mounted on a pneumatically biased shaft  254  which functions to dampen and aid in stopping the movement of the jaw  16  at the appropriate position. A similar damper may be provided to dampen and stop the movement of the jaw  16  as it moves into the parallel pick-up position. It will be apparent that the size of the passages  116 ,  118  and  120  will be sufficient to accommodate any displacement of the jaw  16  by the adjustment mechanism  200 .  
         [0038]     Having described the invention, modifications will be evident to those skilled in the art without departing from the scope of the invention as defined in the appended claims.