Patent Publication Number: US-2003232709-A1

Title: Method and machine for gripping and opening punched cardboard elements and forming open-topped boxes

Description:
DESCRIPTION  
       [0001] The present invention relates to a method and a machine for gripping and opening punched cardboard elements and forming open-topped boxes.  
       [0002] In the technical sector relating to the packaging of containers such as bottles, tins and the like, apparatus able to form an open-topped box inside which said containers are inserted are known.  
       [0003] It is also known that said apparatus usually form part of more complex machines in which, in addition to the box-forming apparatus, devices for forming arrays of containers are provided, said devices operating in parallel and in synchronism with the box-forming apparatus so that the containers and the box reach simultaneously a same station in which means remove the array of containers and insert it into the box which is then closed and conveyed away for storage.  
       [0004] Although performing their function, these box-forming apparatus do not allow high hourly production outputs to be achieved since the forming sequence and the particular configuration of the apparatus itself result in dead time, in particular during closing of the bottom of the box, which cannot be eliminated using the known techniques.  
       [0005] In addition to this, with the known apparatus it is not possible to vary freely the configuration of the box according to the direction of pressing thereof, with the result that, in the case of variation of the latter, complicated retooling of the said apparatus must be performed.  
       [0006] The technical problem which is posed, therefore, is that of providing a method, a device for moving gripping means for containers/boxes, an apparatus for implementing the method and a machine for forming boxes and for filling them with arrays of containers, which are able to eliminate the dead time in the cycle according to the known art and consequently increase the hourly productivity of the forming machines and ensure greater precision and repeatability as regards the form and size of the finished box.  
       [0007] Within the scope of this problem a further requirement is that that the apparatus may be rapidly adapted to any orientation of the cardboard box to be formed without the need for complicated disassembly and retooling thereof. These technical problems are solved according to the present invention by a machine for forming boxes with a closed bottom from punched and folded cardboard elements, which comprises: at least one apparatus for gripping from a store and opening a cardboard element for forming the open box; at least one apparatus for gripping and transporting open boxes; at least one conveyor belt for transporting the formed box to the outlet of the machine, said gripping/opening and gripping/transporting apparatus comprising devices for moving respective gripping/opening means or gripping/transporting means, said devices consisting of at least two controlled axes able to determine free trajectories of the respective gripping/opening or gripping/transporting means in the respective planes.  
       [0008] The present invention relates further to an associated method for gripping and opening punched cardboard elements and forming open-topped boxes. 
     
    
    
     [0009] Further details may be obtained from the following description of a non-limiting example of embodiment of the invention, provided with reference to the accompanying plate of drawings, in which:  
     [0010]FIG. 1 shows a top plan view of the device according to the present invention for moving gripping/transporting apparatus for cardboard boxes and the like;  
     [0011]FIG. 2 shows a cross-sectional view along the plane indicated by II-II in FIG. 1;  
     [0012]FIG. 3 shows a schematically sectioned view, along the plane indicated by III-III in FIG. 4, of a first example of a machine for forming cardboard boxes according to the present invention;  
     [0013]FIG. 4 shows a schematically sectioned view along the plane indicated by IV-IV in FIG. 3;  
     [0014]FIG. 5 shows a schematic perspective view of a first variant of the machine according to FIG. 3;  
     [0015]FIGS. 6 a - 6   l  show schematic views illustrating the working sequence of the machine according to FIG. 5 for forming a box;  
     [0016]FIG. 7 shows a cross-section, similar to that of FIG. 4, of a second example of embodiment of the machine according to the present invention;  
     [0017] FIGS.  8  to  15  show schematic perspective views of application of the device according to the present invention for moving apparatus for gripping containers in machines for filling formed boxes;  
     [0018]FIG. 16 shows a schematic top plan view of a further embodiment of the apparatus according to the invention; and  
     [0019]FIG. 17 shows a schematic view of the station for filling open containers with arrays of bottles. 
    
    
     [0020] As illustrated in FIGS. 1 and 2, the device for moving apparatus for gripping/transporting cardboard elements/containers in particular for box-forming machines, comprises a first fixed support surface  110  which extends lengthwise in a transverse direction Y-Y and on which rails  111  are formed, said rails having, sliding along them, sliding blocks  121  integral with a first carriage  120  which is therefore able to perform a translatory movement in said transverse direction Y-Y. Further pairs of fixed sliding blocks  122  are arranged on the surface of the first carriage  120  opposite to that of the sliding blocks  121 , said additional sliding blocks having a seat  122   a  extending in a longitudinal direction X-X perpendicular to the direction Y-Y. Respective rails  131  are movable inside said seats  122   a , translationwise in the said direction X-X, said rails extending parallel to the longitudinal direction X-X and being integral with a second carriage  130  which is therefore movable translationwise in said longitudinal direction X-X.  
     [0021] The movement of said first carriage  120  and second carriage  130  is determined by the action of respective idle pulleys  133  which are integral with the carriage  130  and  123  integral with the carriage  120  and drive pulleys  113  integral with the fixed surface  110 , all of them being connected by a single drive belt  112 , the ends of which are fixed to the carriage  130 .  
     [0022] The two pulleys  113  integral with the fixed surface  110  are driven by means of respective motors  113   a  controlled by programming and actuating means  160 .  
     [0023] In this way by suitably combining the direction and the speed of rotation of the two opposite drive pulleys  113 , it is possible to obtain a movement of the second carriage  130  along any trajectory of the surface X,Y.  
     [0024] The position of the carriage is detected by means of devices, for example of the encoder type, which are conventional per se and therefore neither illustrated nor described in detail and which are connected in a feedback loop to the programming and actuating means  160 .  
     [0025] The second carriage  130  has attached thereto an arm  135  which extends in the longitudinal direction X-X and on which there are mounted gripping means  140  (FIG. 4) and/or transporting means  150  (FIG. 3) suitable for performing the various steps involved in forming a box  10  and filling it with bottles  20 , described below in connection with the corresponding machine for packaging containers.  
     [0026] Said container packaging machines  200  (FIGS. 3 and 4) essentially consist of a support frame  201  to which the following are connected:  
     [0027] a store  210  for punched and flattened cardboard elements  10  which are fed forwards by devices of the conventional type in a direction parallel to the transverse direction Y-Y so that, in a predefined release position  210   a , a cardboard element is always available; in greater detail said cardboard element is punched so as to produce four folding lines parallel to a vertical axis Z-Z and pairs of transverse bottom and top flaps, respectively at the rear  10   a  and front  10   b  with respect to the direction of feeding of the box towards the outlet of the machine, and bottom and top longitudinal flaps  10   c  and  10   d;    
     [0028] a device  100  for moving gripping means  140  for removing a cardboard element  10  from the position  210   a  and opening it in order to form the open box.  
     [0029] Said means  140  for gripping and opening the box are formed by a first arm  141 , which is fixed to the arm  135  of the second carriage  130  and is equipped with suction cups  141   a , and by a second arm  142  which is equipped with suction cups  142   a  and hinged on said first arm  141  with respect to which it is able to rotate from a substantially perpendicular position to a position substantially parallel thereto;  
     [0030] a second device  100  for moving means  150  for transporting and squaring the box  10 , arranged with a fixed surface  110  substantially parallel to the vertical direction Z-Z; the arm  135  of the second carriage  130  has at its end a prism  150  with dimensions substantially corresponding to the internal dimensions of the box  10  to be formed.  
     [0031] The said prism is positioned substantially aligned with the box  10  so as to be able to enter inside it after it has been opened and is movable, in a direction parallel to the vertical direction Z-Z, so as to be able to enter into and move out of the box, and in a longitudinal direction X-X, so as to be able to transport the said box during closing of the bottom;  
     [0032] first fixed locators  220 , able to co-operate with said forming means  150  so as to close the rear bottom flap  10   a  of the box;  
     [0033] second fixed locators  230  aligned with the first ones  220  and able to co-operate with said forming means  150  so as to close the front bottom flap lob of the box;  
     [0034] fixed guides  240  arranged in front of the said means  220 ,  230  in the direction of feeding of the box and able to co-operate with said forming means  150  so as to close the longitudinal bottom flaps  10   c  of the box;  
     [0035] at least one conveyor belt  250  for transporting the formed box to the outlet of the machine.  
     [0036] With reference to FIGS. 6 a  to  6   l , the operating principle of the machine is as follows:  
     [0037] a) actuation of the apparatus  140  for gripping the cardboard element  10  so as to bring the suction cups  141   a  of the gripping arm  141  into contact with the first side of the cardboard element  10 ; during this step the second arm  142  is arranged perpendicularly with respect to the first arm  141 ;  
     [0038] b) retraction of the carriage  130  in the direction Y-Y so as to remove the cardboard element  10  and simultaneous actuation of the arm  142  which is arranged parallel to the arm  141  so as to be bring the suction cups  142   a  into contact with the other side of the cardboard element  10 ;  
     [0039] c) counter-rotation of the arm  142  which, returning into the position perpendicular to the arm  141 , causes opening of the cardboard element  10  which assumes the form of an open box;  
     [0040] d) retraction of the carriage  130  so that the rear bottom flap  10   a  comes into contact with the fixed locator  220  so as to cause closing thereof;  
     [0041] e) downwards movement of the prism  150  inside the box  10  so that the suction cups of the prism comes into engagement with the internal surface of said closed flap  10   b , retaining it;  
     [0042] f) forward movement of the carriage  120  in the direction X-X so as to displace the boxes integral with the prism in the direction of feeding so that the front bottom flap  10   b  comes into contact with the fixed locators  230  for closing thereof;  
     [0043] g) further forward movement of the carriage  130  supporting the prism  150 , so that the bottom part of the box passes above the devices  260  for applying glue onto the bottom flaps  10   a ,  10   b ; and  
     [0044] h) by means of the fixed means  240  for closing the longitudinal bottom flaps  10   c;    
     [0045] i) forward movement of the prism  150  in the direction X-X so as to bring the box onto the conveyor belt  250  and downwards movement of the carriage  130  in the vertical direction Z-Z so as to exert a thrust in the vertical direction which causes compression of the longitudinal flaps  10   c  onto the transverse flaps  10   a ,  10   b  situated between the said prism and the conveyor belt  250  so as to produce definitive closure of the bottom of the box;  
     [0046] l) raising of the prism in the vertical direction Z-Z and translation thereof in the direction X-X for return into the initial position at the start of the cycle.  
     [0047] Although described with reference to formation of a single box  10  with a single prism  150 , it can be seen from FIG. 5 how, in the case of small longitudinal dimensions of the box, it is possible to envisage a double store  210  of cardboard elements  10 , two gripping devices  140  and two prisms  150  integral with the transporting apparatus  100  so to obtain doubling of the hourly production.  
     [0048] In addition to this, it is envisaged that in a preferred embodiment the gripping devices  140  are rotatable about a transverse axis  146  so as to be able to position the second arm  142  in a rear position (illustrated) or front position (not illustrated) with respect to the direction of feeding and with respect to the edge of the cardboard element.  
     [0049] This allows cardboard elements to be opened, whatever the relative position of their folding lines and the direction of pressing thereof and without the need for retooling of the machine, providing the latter with a great degree of versatility.  
     [0050] Similarly (FIG. 7) it is also possible to envisage that the forming machine  1200  has two conveyor belts  250  which are parallel to each other and a double position for opening the cardboard element  10 ; in this configuration, two gripping and transporting apparatus  150  arranged parallel to each other (not shown) are envisaged, but only one apparatus  140  for gripping and opening the cardboard elements; the latter apparatus in fact requires a cycle time which is approximately half the cycle time of the transporting apparatus.  
     [0051]FIG. 16 also shows a further embodiment of the apparatus for gripping the cardboard elements which in this case is arranged with the fixed surface oriented parallel to the longitudinal axis X-X and movable arm oriented in the transverse direction Y-Y.  
     [0052] In a similar manner to the gripping and transporting apparatus  100 , the movable arm has at its free end a cross member  136  on which the devices  140  for gripping and opening the cardboard element are mounted.  
     [0053] The machine and the forming sequence described above are essentially based on a new box forming method which envisages the steps of:  
     [0054] a) actuating an apparatus  140  for gripping the cardboard element  10  so as to bring first gripping means  141   a  into contact with the first side of the cardboard element  10 ;  
     [0055] b) retraction of said gripping means  141   a  in the direction Y-Y in order to remove the cardboard element  10 , and simultaneous actuation of second gripping means  142   a  so as to bring them into contact with the other side of the cardboard element  10 ;  
     [0056] c) return of the second gripping means into the initial position so as to cause opening of the cardboard element  10  which assumes the form of an open box;  
     [0057] d) retraction of the gripping means  140  in the longitudinal direction of feeding X-X of the box  10  so that the rear bottom flap  10   a  comes into contact with the fixed locator  220  so as to cause closing thereof;  
     [0058] e1) actuation, in a vertical direction Z-Z, of an apparatus for gripping and transporting the open box  10  so as to bring associated squaring and gripping means inside the box  10 ;  
     [0059] e2) engagement of squaring and gripping means with the rear bottom flap  10   a  of the box;  
     [0060] f) forward movement of the squaring and gripping means in the direction X-X so as to displace the boxes such that the front bottom flap  10   b  comes into contact with the fixed locators  230  for closing thereof;  
     [0061] g) further forward movement of the squaring and gripping means so as to cause the bottom part of the box to pass over the devices  260  for applying glue to the bottom flaps  10   a ,  10   b ; and  
     [0062] h) by means of the fixed means  240  for closing the longitudinal bottom flaps  10   c;    
     [0063] i1) forward movement of the squaring and gripping means in the direction X-X so as to bring the box onto the conveyor belt  250 ;  
     [0064] i2) downward movement of the squaring and gripping means in the vertical direction Z-Z so as to exert a thrust in the vertical direction which produces compression of the longitudinal flaps  10   c  onto the transverse flaps  10   a ,  10   b  situated between the said prism and the conveyor belt  250  for definitive closing of the bottom of the box;  
     [0065] l1) raising of the squaring and gripping means in the vertical direction Z-Z;  
     [0066] l2) translation of the said means in the direction X-X for return into the initial start-of-cycle position.  
     [0067] As illustrated in FIGS.  8  to  10 , the device  100  for moving apparatus for gripping containers  20  may also be used for gripping and transporting arrays of containers  20  to be inserted inside formed open-topped boxes in the corresponding station of packaging machines.  
     [0068] In greater detail:  
     [0069]FIG. 8 shows a machine  1200  with feeding of boxes and containers in parallel directions; in this case the gripping and transporting apparatus  1150  is arranged transversely with respect to the direction of feeding;  
     [0070]FIG. 9 shows a machine  1200  which is similar to that of FIG. 8 and in which containers  120  of heavier weight are packaged; correspondingly in this case the gripping and transporting apparatus  2150  envisages a double actuating device  2100  for adapting it to the greater weight of the containers  120 ;  
     [0071]FIG. 10 shows a machine  2200  with feeding of boxes  20  and containers  10  in parallel and superimposed directions; in this case the gripping and transporting apparatus  2150  is in turn parallel to the direction X-X of feeding and, as illustrated, the actuating device  2100  may be doubled so as to be adapted to the greater weight of the containers  120 ;  
     [0072]FIG. 11 shows a machine  3200  which is similar to that of FIG. 8 and in which containers  220  of further increased weight are packaged; in this case the gripping and transporting apparatus  3150  envisages two separate actuating devices  3100  which are individually attached to a support structure  3201  and connected together by bars  3021   a  with which the means  3150  for gripping the containers  220  are integral.  
     [0073] FIGS.  12  to  15  show machines which are respectively similar to the corresponding FIGS.  8  to  11  and in which two rows of boxes and containers are fed.  
     [0074]FIG. 17 shows the station  5000  for filling the boxes  10  which are fed to the said station  5000  by means of a first conveyor belt  250 , with bottles  5001  fed by means of a second conveyor belt  5250 , on which parallel rows travel.  
     [0075] An apparatus  5100  for gripping an array of bottles and depositing them inside the box  10  is arranged in the station  5000 .  
     [0076] As illustrated, the fixed arm  5110  of the apparatus is arranged in a plane inclined from the bottom upwards in the direction of feeding of the bottles and the boxes and transversely between the two conveyor belts  250 , 5250  so that the lowermost end corresponds to the bottles and the uppermost end corresponds to the boxes.  
     [0077] With this arrangement of the fixed arm  5110 , the translation of the movable arm  5130  which carries the means  5150  for gripping the array of bottles  5001 , from the position for gripping the bottles, into the position for depositing them in the box  10 , produces a simultaneous change in height, resulting consequently in elimination of a downward/upward stroke in the overall cycle which is performed as follows:  
     [0078] positioning of the gripping arm at the lowermost end and gripping of the bottles;  
     [0079] starting movement of the movable arm  5130  from the lowermost end of the fixed arm  5110 ;  
     [0080] outward stroke of the movable arm  5130  towards the top end of the fixed arm  5110 , with simultaneous upwards movement of the bottles beyond the height of the upper free edge of the box;  
     [0081] downward movement of the movable arm inside the box;  
     [0082] release of the array of bottles;  
     [0083] upward movement again of the movable arm;  
     [0084] return stroke towards the bottom end of the fixed arm.  
     [0085] All the figures are self-explanatory for a person skilled in the art and therefore do not require a more detailed description.  
     [0086] Although the description has been provided identifying for the sake of convenience the directions as X-X=longitudinal, Y-Y=transverse and Z-Z=vertical, it is obvious for the technical expert how the device, apparatus and machine may be oriented in an equivalent manner in any direction.  
     [0087] With the method and the machine described above it is possible to achieve a reduction in the dead time of the cycle, since it is not envisged using auxiliary means such as pistons and the like during the closing step, as well as an improvement in the quality of the formed boxes since the internal gripping means according to the invention ensure greater squaring and repeatability of the said boxes.