Abstract:
The invention relates to a method and device for erecting (flat) blanks ( 12 ) for cartons, collapsible boxes, trays ( 11 ) or the like. Said blanks ( 12 ) are moved before an aperture ( 16 ) of a forming shaft ( 17 ) and introduced therein with a forming punch ( 20, 22 ), which in particular can be raised and lowered, with parts of the blank ( 12 ) being erected, in particular those in the region of side walls ( 15 ) and longitudinal walls and/or transverse walls of the carton or the like.  
     According to the invention, after a blank ( 12 ) has been pushed into the forming shaft ( 17 ), the forming punch ( 20, 22 ) is moved at least partially outside of the forming shaft ( 17 ) to a position in front of the aperture ( 16 ) of the forming shaft ( 17 ). It is preferably provided that the forming shaft ( 17 ) is assigned at least two forming punches ( 20, 22 ), which are moved respectively in succession to press a (separate) blank ( 12 ) into the forming shaft ( 17 ). The forming punches ( 20, 22 ) are pivoted out of the forming shaft ( 17 ). The forming punches ( 20, 22 ) are preferably pivoted out of the forming shaft ( 17 ) in a direction opposite to the direction in which the blanks ( 12 ) are pressed into the forming shaft ( 17 ).

Description:
STATEMENT OF RELATED APPLICATIONS  
       [0001]     This patent application is the United States Patent Cooperation Treaty (PCT) Chapter II National Phase of PCT/EP2003/013268 having an international filing date of 26 Nov. 2003, which claims priority on German patent application no. 10255503.6 having a filing date of 22 Nov. 2002. The PCT applicant is Focke &amp; Co. (GmbH &amp; Co. KG), having a business address of Siemensstrasse 10, 27283 Verden, Germany. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Technical Field  
         [0003]     The invention relates to a method for erecting (flat) blanks for cartons, collapsible boxes, trays or the like. Said blanks are moved before an aperture of a forming shaft and introduced therein with the aid of a forming punch, which in particular can be raised and lowered, whereby certain parts of the blank, in particular those in the region of longitudinal walls and/or transverse walls of the carton or the like, are erected in the process.  
         [0004]     2. Prior Art  
         [0005]     In known devices of the type mentioned above, a blank is first moved in front of the aperture of a forming shaft and pushed into said shaft by the forming punch, with parts of the blank being erected or folded. Following this, the forming punch is drawn out of the forming shaft as the next blank is moved in front of the aperture of the forming shaft, and the entire process is repeated.  
       BRIEF SUMMARY OF THE INVENTION  
       [0006]     The object of the invention is to develop a method and a device of the aforementioned type, in particular to propose measures which result in increased operating speed.  
         [0007]     To achieve this object, the method according to the invention is characterized in that, once the blank has been introduced into the forming shaft, the forming punch is moved at least partially out of the forming shaft to a position before the aperture thereof. In the process, the forming punch is moved, in particular pivoted, out of the forming shaft in a direction opposite to the direction in which the blanks are introduced. Preferably, therefore, the forming punch is not returned through the aperture but rather is guided at least partially in a (sub)region outside the forming shaft. This arrangement ensures that the next blank to be erected can already be moved, in particular conveyed, in front of the aperture of the forming shaft before the forming punch has attained its initial position before the opening of the forming shaft.  
         [0008]     Pursuant to an advantageous development of the invention, the forming shaft is assigned at least two forming punches that are moved in succession for each of them to push a (separate) blank into the forming shaft. With this arrangement the operating speed of the device can be doubled while maintaining the same speed of the forming punches. A preferred embodiment of the invention provides two forming punches which are operated offset to one another such that a second forming punch starts pressing a blank through the aperture of the forming shaft when a first forming punch has essentially finished the erection of another blank, in particular when it has transferred this blank to a conveying means employed for carrying off the at least partially erected blanks.  
         [0009]     Preferably the input of the blanks as well as the drive of the forming punches are executed continuously, thus helping to avoid stress to the device caused by discrete cyclic operations.  
         [0010]     A device for achieving the aforementioned object is a device for erecting (flat) blanks for cartons, collapsible boxes, trays or the like, it being possible to move said blanks in front of an aperture of a forming shaft and introduced therein by means of a forming punch, which in particular can be raised and lowered, whereby parts of the blank, in particular those in the region of side walls or longitudinal walls and/or transverse walls of the carton or the like, are erected in the process, characterized in that, once the blank has been pressed into the forming shaft, the forming punch can be moved at least partially outside of the forming shaft and returned to a position in front of the aperture of the forming shaft, it being possible to move the forming punch out of the forming shaft in a direction opposite to that of pressing in the blanks. Preferably at least two forming punches are likewise provided which can be moved in succession through the forming shaft. The forming punches are each rotatably, in particular pivotably, mounted on a carriage or slide located outside the forming shaft, which can be displaced upwards and downwards, and are preferably moved by a respective continuously-driven belt.  
       BRIEF SUMMARY OF THE DRAWINGS  
       [0011]     Preferred developments on the method and device according to the invention are disclosed in the dependent claims and the remaining description. In the following, an exemplary embodiment will be illustrated on the basis of the drawings, which show  
         [0012]      FIG. 1 a  schematic side view of a device for erecting blanks,  
         [0013]      FIG. 2 a  vertical section of the device pursuant to  FIG. 1 ,  
         [0014]      FIG. 3 a  schematic view showing the path of movement of a forming punch of the device,  
         [0015]      FIG. 4 a  cross-sectional view through a part of the device, on an enlarged scale,  
         [0016]      FIG. 5  schematic side view of an alternative embodiment of the device pursuant to  FIG. 1 ,  
         [0017]      FIG. 6  the device pursuant to  FIG. 5  in a vertical sectional view along intersecting line VI-VI, and  
         [0018]      FIG. 7 a  horizontal sectional view through the device along intersecting line VII-VII in  FIG. 6 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0019]     The FIGS.  1  to  7  show parts of a device for the cartoning of products  10 . Here the products  10  are packed in trays  11 . But in place of the shown trays  11 , it is also possible to use other arbitrary (bundle) packages, such as cartons, collapsible boxes or the like.  
         [0020]     The trays  11  are made from essentially flat blanks  12  made of paper, (corrugated) cardboard, plastic or the like. To this end, the blanks  12  are taken from a stack of blanks  13 . The individual blanks  12  lie flat in the pile of blanks  13  and on top of one another, preferably with an essentially horizontal extension. The stack of blanks  13  can also be located in a blanks magazine from which the blanks  12  can be separately conveyed or removed.  
         [0021]     For forming the trays  11  or cartons, collapsible boxes or the like, the blanks  12  are fed to an erecting station  14 . In this station the essentially flat blanks  12  are prepared for receiving the products by erecting parts of the blank  12 , for example by the folding of lateral walls or transverse walls into an upright position. In the shown exemplary embodiment, a part of the upright side wall  15  of the tray  11  is formed in the erecting station  14 . Depending on the type of the package to be produced, it is also possible to erect additional side walls, in particular all side walls, in the erecting station  14 .  
         [0022]     In the following, the special features of the erecting station  14  will be described in conjunction with FIGS.  1  to  4  for a first exemplary embodiment.  
         [0023]     The blanks  12  are conveyed in front of the aperture  16  of a forming shaft  17  of the erecting station  14 . The aperture  16  is delimited by at least two walls of the forming shaft  17 , which are arranged opposite to one another and which in a lower region are disposed in an essentially vertical direction and preferably run in a straight plane. In the region of the aperture  16 , the side walls  19  open out in a funnel-like shape, preferably having a circular radius in the region of the aperture. Continuing from this region the side walls run approximately horizontally as a support surface for the blanks  12 . Two other side walls of the forming shaft  17 , which has a rectangular outline, are left open to avoid interfering with the movement path of the forming punch  20 . The size of the aperture  16  is dimensioned such that the blank  12  lies on the funnel-shaped side walls  19  in the region of two opposite edges. The dimension of the blank  12  transverse thereto, for example its width, is less than the clear width of the forming shaft  17 .  
         [0024]     The blanks  12  are pushed individually into the forming shaft  17  by a forming punch  20  as parts of the blank  12  are turned up as they press against the region of the forming shaft  17  where the side walls  19  narrow in a funnel-like shape in the conveying direction. The forming punch  20  retains an approximately horizontal orientation during the entire process of pushing the blanks into the forming shaft  17 . The partially folded or erected blanks  12  are conveyed by the forming punch  20  downward in the forming shaft  17  in an approximately vertical direction and are immediately transferred to a conveying means  21  running below the forming shaft  17  which transports the partially folded blanks  12  out of the region of the forming shaft  17 .  
         [0025]     A first special feature of the erecting station  14  lies in the return of the forming punch  20  to a position in front of the aperture  16  of the forming shaft  17  after a blank  12  has been pushed into the forming shaft  17 . After the blanks  12  have been transferred to the conveying means  21 , the forming punch  20  is moved out of the forming shaft  17  and guided upwards such that the forming punch  20  is moved at least in part outside of the forming shaft  17  and returned in front of the aperture  16 . By virtue of this arrangement it is possible to convey the next blank  12  into the region of the aperture  16  during the return movement of the forming punch  20 . The blanks  12  can thus be moved or conveyed continuously in front of the aperture  16 .  
         [0026]     Another special feature is that the (individual) forming shaft  17  is assigned a plurality of forming punches  20 ,  22 . The forming punches  20 ,  22  are passed through the forming shaft  17  in succession, with each forming punch  20 ,  22  pressing in each case a single blank  12  into the forming shaft  17 . The forming punches  20 ,  22  are arranged such that they are passed through the forming shaft  17  at a (temporal and spatial) distance to one another. Provided in the shown exemplary embodiment is that as a blank  12  is being transferred by the forming punch  22  to the conveying means  21 , at approximately the same time the other forming punch  20  is pivoted in front of the aperture  16  for pushing in the following blank  12 . In the case shown here, this results in a doubling of the cycle rate. The successive forming punches  20 ,  22  are sufficiently spaced apart such that there is enough room to move the lower forming punch  20 ,  22  outwards. As an alternative, it is possible to provide more than two forming punches  20 ,  22 .  
         [0027]     Also of significance is the manner in which forming punches  20 ,  22  are moved out of the forming shaft  17  ( FIG. 3 ). After a blank  12  is transferred to the conveying means  21 , the forming punches  20 ,  22  are first swiveled about a pivot  23  to assume an approximately vertical orientation as they move out of the forming shaft  17 . The pivoting of the forming punches  20 ,  22  is executed counter to the direction in which the blanks  12  are pushed in. Preferably the completed swiveling movement is followed by the upward movement of the forming punches  20 ,  22 , with the vertical orientation of the forming punches  20 ,  22  being retained. At an upper final position the forming punches  20 ,  22  are swiveled into an approximately horizontal position before the aperture  16  of the forming shaft  17 . This is followed by the vertical downward movement of the forming punches  20 ,  22 , which have an approximately horizontal orientation and preferably with their full surface on a blank  12 . The movement cycle ends when the blanks  12  are transferred to the conveying means  21 .  FIG. 3  schematically illustrates this motion sequence for shaping stamp  22  shown in  FIG. 2 .  
         [0028]     It goes without saying that forming punch  20  is moved in an analogous manner. The motion sequence of the forming punch  20  can be seen as a mirror image of the motion sequence for the forming punch  22  shown in  FIG. 3 , since the two forming punches  20 ,  22  are arranged opposite one another on the forming shaft  17 . In addition, it is possible to overlay the movement of the forming punches  20 ,  22  in the vertical direction with their pivoting or swiveling movement.  
         [0029]     The two forming punches  20 ,  22  are each driven by a separate endless conveyor. A drive motor  24  powers, by means of a drive shaft  25 , two toothed belts  26  as endless conveyors which are arranged at either side of the forming shaft  17  and run in the vertical direction and which are assigned a respective forming punch  20 ,  22 . To this end, the drive shaft  25  is coupled with a respective top cogwheel  27  which drives the toothed belt  26 . The direction of movement of the toothed belts  26  run counter to each other, as indicated by the arrows in  FIG. 2 . Furthermore, in each case lower cogwheels  28  are provided around which the toothed belts  26  are guided. In the shown exemplary embodiment, each forming punch  20 ,  22  is assigned its own toothed belt  26 . In the case involving more than two forming punches  20 ,  22 , forming punches  20 ,  22  disposed on the same respective side of the forming shaft  17  can be driven preferably by a common toothed belt  26 .  
         [0030]     In order to move the forming punches  20 ,  22 , the toothed belts  26  are each coupled to a carrier  29 . The carriers  29  are coupled in the region of a lateral free end to the toothed belts  26 . The adjacent free lateral end  30  of the carriers  29  is in addition displaceably mounted in an oval curved track  31 , namely by means of a annular bearing bush  32 . The curved track  31  is recessed in a bearing block  33  which otherwise has an essentially rectangular outline. This bearing block  33  extends at least over the entire height of the toothed belt  26 . Another opposite lateral end  34  of the carrier  29  extends through a bore hole  35  in the forming punches  20 ,  22 . As can be seen in  FIG. 2 , the forming punches  20 ,  22  are mounted on the carriers  29  in the region of a lateral free end of the latter. By virtue of the driving action of the toothed belt  26  about the cogwheels  27 ,  28 , the carrier  29  is guided in the curved track  31  along the oval path of movement  36  shown in  FIG. 3 .  
         [0031]     The design of the forming punches  20 ,  22  and the arrangement of the pivot  23  result in the advantageous path of movement  37  of the forming punches  20 ,  22 , as shown schematically in  FIG. 3 . As can be seen from  FIG. 2 , the forming punches  22  are configured with an approximately L-shaped cross-section that features a first, longer leg  38  and a second shorter leg  39 . The shorter leg  39  is also angled, or elbowed. For abutting the blank  12 , the longer legs  38  of the forming punches  20 ,  22  have in part a rectangular or square outline. In order to reduce their weight, the forming punches  20 ,  22  have a center recess  40 . As already described, the forming punches  20 ,  22  are attached to the carriers  29  in the region of a lateral end of the forming punches  20 ,  22 , namely in the vicinity of their elbowed region. Configured in a centered position in the angled or elbowed region is also the second pivot  23 . To this end, the forming punches  20 ,  22  are rotatably mounted on an axis  41 , which in turn is mounted in a projected manner on a carriage  42  that can be moved up and down. The carriage  42  is displaceably mounted on two guide rails  43  in an exclusively vertical direction. The guide rails  43 , which are assigned to the bearing blocks  33 , run on either side of the toothed belts  26 . The guide rails  43  determine the path of movement of the axis  41 , or pivot  23 . The latter can accordingly be moved only in the vertical direction, namely upwards and downwards.  
         [0032]     The mounting of the forming punches  20 ,  22  on the vertically displaceable pivot  23 , or axis  41 , and their additional mounting on the combination of toothed belt  26  and carriers  29 , which is driven along the curved track  21 , results in the movement of the forming punches  20 ,  22  shown in the schematic illustration in  FIG. 3 . The legs  38  that come to rest on the blanks  12  are pivoted in front of the aperture  16  and above the latter and moved into the forming shaft  17  as they take along and erect a single blank  12 . The forming punches  20 ,  22  are moved downward along with the blank  12  in the forming shaft  17  until the blanks  12  come to rest on the conveying means  21 . The forming punches  20 ,  22  are then pivoted laterally out of the forming shaft  17  counter to the vertical conveying direction of the blanks  12  and returned outside of the forming shaft  17  back to a position in front of the aperture  16  of the forming shaft  17 . During this process the toothed belts  26  are driven continuously.  
         [0033]     Following the conveying path of the blanks in the forming shaft  17  is a laterally directed transport of the partially folded blanks  12 . The conveying means  21  are provided for this purpose. The conveying means  21  comprise preferably one or more parallel (endless) conveyor belts  45  that are driven by deflection rollers  46 . The one or more conveyor belts  45  can be arranged below the forming shaft  17  or run partially through it.  
         [0034]     In the shown exemplary embodiment two parallel conveying belts  45  are provided as endless conveyors whose deflection rollers  46  are arranged on a common axis. The partially folded blanks  12  are placed upon the conveyor belts  45  by the forming punches  20 ,  22  as described, namely precisely between carriers  48  which are disposed on the outer side of the conveyor belt  45 . The carriers  48  are arranged in pairs, with the mutually facing upright side surfaces of the paired carriers  48  being tapered. The space between each pair of carriers  48  thus widens in the upward direction. The minimum distance between a pair of carriers  48  corresponds approximately to the corresponding cross-sectional dimension of the tray  11 . The conveying means  21  transports the partially folded blanks  12  laterally out of the erecting station  14 . Subsequently, other side walls are erected or folded and connected to the already erected side walls  15 , for example by the application of glue. The erection of the other side walls and their adhesive bonding to the side walls  15  folded in the erecting station  14  is preferably executed after the products  11  have been set down from above into or on the partially folded blank  12 . The erecting or upright folding of the remaining side walls can be performed with the assistance of special folding members or folding guides. The glue is preferably applied in the region of folding flaps  49 .  
         [0035]     The described device and method for erecting the blanks  12  is preferably conducted in a completely continuous manner. This also applies to the introduction of blanks  12  from the stack of blanks  13  and the lateral transport of the partially folded blanks  12  on the conveying means  21 .  
         [0036]      FIG. 5  to  7  show a second preferred exemplary embodiment. Inasmuch as the components of this device described in the following match the functional features of the components described in the first exemplary embodiment, the same reference numbers will be used for their designation.  
         [0037]     The device shown in the second exemplary embodiment differs from the exemplary embodiment pursuant to  FIG. 1  to  4  merely with respect to the constructive design of the erecting station  14 , namely with respect to the means provided for executing the movement of the forming punches  20 ,  22 . The pushing-down movement of the forming punches  20 ,  22  and their withdrawal from the forming shaft  17  are essentially identical to that of the first exemplary embodiment.  
         [0038]     As in the first exemplary embodiment, the blanks  12  are removed individually from a stack of blanks  13  and moved in front of the aperture  16  of a forming shaft  17 . There the separate blanks  12  are gripped on the top by a forming punch  20 ,  22  and pressed into the forming shaft  17 , with at least part of the blank  12  being erected. Arranged below the forming shaft  17 , as in the first exemplary embodiment, is an endless conveyor comprising two parallel conveyor belts  45 . Individual blanks  12  are set down by the forming punches  20 ,  22  between carriers  48  on the top side of the conveyor belts  45 . The conveying means  21  formed by the conveyor belts  45  is preferably configured as a continuously driven endless conveyor and serves to convey the at least partially folded or erected blanks  12  out of the erecting station  14 . As in the first exemplary embodiment, the folding or erecting of the blanks  12  is completed during the further lateral or horizontal transport on the conveying means  21 .  
         [0039]     As in the first exemplary embodiment, two forming punches  20 ,  22  are provided. In contrast to the previous exemplary embodiment, the forming punches  20 ,  22  here in their horizontal projection are disposed on the same side of the forming shaft  17 . Each of the forming punches  20 ,  22  are pivotably mounted on a carriage  50  which can be moved along a linear axis  51 . The linear axes  51  in the shown exemplary embodiment assume an essentially vertical orientation so that the forming punches  20 ,  22  can be moved up and down along the linear axes  51  in a vertical direction. The carriages  50  are each assigned a servomotor  52  which makes it possible to swivel the forming punches  20 ,  22 , which are mounted on the carriages  50 , about a pivot  23 .  
         [0040]     With the help of the vertically displaceable carriages  50  and the pivotable forming punches  20 ,  22  attached thereto, it is possible to realize the motion sequence described in the first exemplary embodiment. The forming punches  20 ,  22  are respectively pivoted in succession to lie against a blank  12  lying flat on the side walls  19  of the forming shaft  17 . By virtue of the downward movement of the carriages  50  in the essentially vertical direction, the blanks  12  are pressed individually into the forming shaft  17  as the blanks  12  are at least partially erected. During the entire process of pushing in the blanks  12 , the forming punches  20 ,  22  assume an approximately horizontal orientation. In a lower final position of the carriages  50  the blanks  12  are transferred by the forming punches  20 ,  22  to the conveying means  21 . The forming punches  20 ,  22  are then swiveled about the pivot  23  counter to their pressing-down movement and moved out of the forming shaft  17  to assume an upright, essentially vertical position. The carriages  50  are then moved upwards until they reach an upper end position with the essentially vertical orientation of the forming punches  20 ,  22  being maintained. Finally, the forming punches  20 ,  22  are moved in their pressing-down direction to assume an approximately horizontal position in which the forming punches  20 ,  22  lie on the top side of the blanks  12  at the height of the aperture  16  of the forming shaft  17 .  
         [0041]     As in the first exemplary embodiment, the forming punches  20 ,  22  are moved through the forming shaft  17  spaced or offset from one another in time and distance such that after a lower forming punch  22  swivels back, the upper forming punch  20  can be moved along with a blank  12  into the forming shaft  17 . The forming punches  20 ,  22  can thus be returned to an upper initial position while the respective other forming punch  20 ,  22  is already passing through the forming shaft  17 . As in the first exemplary embodiment, this arrangement achieves a doubling of the cycle rate. As in the first exemplary embodiment, the forming punches  20 ,  22  are swiveled back counter to the pressing-in direction of the blanks. The forming punches  20 ,  22  are moved back in front of the aperture  16 , as in the first exemplary embodiment, essentially outside of the forming shaft  17 . Depending on the length of the vertical path of movement of the forming punches  20 ,  22 , the swiveling movement can also be combined with the upwards or downwards movement.  
         [0042]     The linear axes  51  each contain endless conveyors, for example continuously driven toothed belts, drive belts or the like, which are respectively guided around a lower deflection roller  53  and an upper, common transmission shaft  54 . The two circulating conveyor belts in the linear axes  51  are driven by a common servomotor  55  that is coupled with the transmission shaft  54 . The mutually opposite movement of the two forming punches  20 ,  22  results from the respective arrangement of the carriages  50  on the opposing conveyor strands of the respective endless conveyors of the linear axes  51 . The carriage  50  associated with the forming punch  20  is arranged on a conveyor strand facing the forming shaft  17 , while the carriage  50  associated with the forming punch  22  is arranged on conveyor strand of the linear axis  51  facing away from the forming shaft  17  ( FIG. 7 ).  
         [0043]     As can also be seen from  FIG. 7 , the two linear axes in their horizontal projection are arranged on the same side of the conveying belt  45  of the conveying means  21 . One linear axis  51  is arranged approximately at the height of the forming shaft  17 , whereas the second linear axis  51 , which in the shown exemplary embodiment moves the forming punch  20 , is laterally offset to the forming shaft  17 . Because of this arrangement the arms  56 ,  57  which connect the forming punches  20 ,  22  to their respective carriages  50  are have a multi-angled or elbowed configuration. In the shown exemplary embodiment, the arms  56 ,  57  each have a double-angle configuration, as seen in their horizontal projection and from the side view, for bridging the space between the linear axes  51  and the forming shaft  17 .  
       LIST OF DESIGNATIONS  
       [0044]      10  product  
         [0045]      11  tray  
         [0046]      12  blank  
         [0047]      13  stack of blanks  
         [0048]      14  erecting station  
         [0049]      15  lateral wall  
         [0050]      16  aperture  
         [0051]      17  forming shaft  
         [0052]      19  side wall  
         [0053]      20  forming punch  
         [0054]      21  conveying means  
         [0055]      22  forming punch  
         [0056]      23  pivot  
         [0057]      24  drive motor  
         [0058]      25  drive shaft  
         [0059]      26  toothed belt  
         [0060]      27  cogwheel  
         [0061]      28  cogwheel  
         [0062]      29  carrier  
         [0063]      30  lateral end  
         [0064]      31  curved track  
         [0065]      32  bearing bush  
         [0066]      33  bearing block  
         [0067]      34  lateral end  
         [0068]      35  bore hole  
         [0069]      36  path of movement  
         [0070]      37  path of movement  
         [0071]      38  leg  
         [0072]      39  leg  
         [0073]      40  recess  
         [0074]      41  axis  
         [0075]      42  carriage  
         [0076]      43  guide rail  
         [0077]      44  recess  
         [0078]      45  conveyor belt  
         [0079]      46  deflection roller  
         [0080]      47  axis  
         [0081]      48  carrier  
         [0082]      49  folding flap  
         [0083]      50  carriage  
         [0084]      51  linear axis  
         [0085]      52  servomotor  
         [0086]      53  deflection roller  
         [0087]      54  transmission shaft  
         [0088]      55  servomotor  
         [0089]      56  arm  
         [0090]      57  arm