Abstract:
A case loading machine and method of operation is described for positioning at least two flexible bags, having an unstable product therein, in a case and in side-by-side contact with one another. A case engaging and displacement mechanism is positionable inside a case from an open top end of the case whereby to divide the case into compartments of predetermined size. The mechanism holds the case at a loading position with one of the compartments aligned at a bag receiving position. A bag engaging and transfer mechanism engages one of the bags from a bag filling position and transfers it into the aligned compartment. The bag engaging and transfer mechanism is provided with a compression compartment to compress the flexible bag and displace the unstable product therein whereby the bag is sized to enter into the aligned compartment. The case is then displaced to align another compartment at the loading position to receive a further bag. Once a case is filled with a predetermined number of bags, a new case is engaged and the loading process repeats itself.

Description:
TECHNICAL FIELD 
     The present invention relates to a case loading machine and method of operation for positioning at least two flexible bags, having an unstable product therein, in a case and in side-by-side contact with one another. 
     BACKGROUND ART 
     Various machines are known for casing unstable products that are contained in bags. However, most of these machines and processes simply drop predetermined number of packages in an open top end of a box and the box is sized to accept predetermined quantities of these products which are released in an orderly or disorderly fashion. Many known case loading machines also utilize vacuum suction cups to engage, displace and position products within a case. A typical example of machines for packaging flexible packages is described in U.S. Pat. No. 5,044,143. 
     When handling flexible bags which contain an unstable product therein, such as milk pouches, the bag deforms itself by the weight of the liquid therein and the bottom part of the bag expands. This poses problems when a predetermined number of bags need to be positioned within a case in an orderly fashion whereby the bags are all visible from the open top end of the case while at the same time the bags occupy a substantial portion of the volume of the case. Heretofore, these products have been packaged in boxes or cases in a disorderly fashion stacked one on top of each other. Consequently, the bag at the bottom of the box bears the weight of all the other bags on top of it. This often causes the bottom bags to burst during manipulation of the case or when in transit in a vehicle, particularly when the vehicle is subjected to rough road conditions imparting movement and shocks to the cases. Not only does the bag at the bottom of the case burst, but the liquid products within the bags will often soil bags in adjacent cases depending on how these cases are transported and disposed in the vehicle. The result of this is very costly and time-consuming to rectify. 
     SUMMARY OF INVENTION 
     It is a feature of the present invention to provide a case loading machine and method of operation which is capable of positioning at least two flexible bags, having an unstable product therein, in a case and in side-by-side contact with one another while occupying a substantial volume of the case and machine and method substantially overcomes the above-mentioned disadvantages of the prior art. 
     According to the above feature, from a broad aspect, the present invention provides a case loading machine for positioning at least two flexible bags, having an unstable product therein, in a case and in side-by-side contact with one another. The machine comprises case engaging and displacement means having at least one rigid division wall plate positionable inside the case from an open top end of the case to divide the case into two or more compartments of predetermined size. The case engaging and displacement means holds the case at a loading position with one of the compartments aligned at a bag receiving position. Bag engaging and transfer means is provided for engaging one of the bags, from a bag filling position, and transferring same in the said one compartments aligned at the bag receiving position. The bag engaging and transfer means has compression means to compress the flexible bag and displace the unstable product therein whereby the bag is sized to enter into the aligned one of the compartments. The case engaging and displacement means displaces the case to align the other of the two compartments, sequentially, at the loading position to each receive a further bag from the bag engaging and transfer means. Means is provided to feed another case to the case engaging and displacement means. 
     According to a still further broad aspect of the present invention there is provided a method of positioning two or more flexible bags, having an unstable product therein, in a case and in side-by-side contact with one another. The method comprises the steps of engaging a case at a case loading position from an open top end thereof and segmenting the case into compartments. The method also includes displacing the case to position the compartments, in sequence, at a bag receiving position. The filled bag with the unstable product therein is displaced to a bag transferring means. The bag with the unstable product is then compressed in the bag transferring means to size the bag to enter into the compartment positioned at the bag receiving position. The case is then displaced to load all of the compartments in sequence at the bag receiving position. The case, filled with a predetermined quantity of the bags is then released and another case is engaged. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     A preferred embodiment of the present invention will now be described with reference to the accompanying drawings in which: 
     FIG. 1 is a simplified side view of the case loading machine of the present invention; 
     FIG. 2 is a perspective view of the case engaging and displacement mechanism incorporating the compartment division walls; 
     FIG. 3 a  is a fragmented side view of the bag loading chute and the top end of the inclined conveyor; 
     FIG. 3 b  is a fragmented perspective view of a bag being loaded with pouches having an unstable product therein; 
     FIG. 3 c  is a simplified side view showing how a bag is opened; 
     FIG. 3 d  is an end view of the chute and the trap door linkage assembly; 
     FIG. 3 e  is a side view of FIG. 3 d  showing the bag engaging and transfer mechanism; 
     FIG. 4 is a top view of the bag engaging and transfer mechanism and the case positioning system; and; 
     FIG. 5 is a fragmented simplified top view showing the construction of the case engaging and displacement mechanism. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring now to the drawings, and more particularly to FIG. 1, there is shown generally at  10  the case loading machine of the present invention associated with a feed conveyor and bag filling machine  22 . More specifically, the case loading machine  10  as herein described is utilized for placing plastic bags  21 , containing a plurality of small liquid pouches  12 , into a case  11  and in side-by-side relationship therein while occupying a substantial portion of the volume of the case. 
     As shown in FIG. 1, small pouches  12  are formed and filled with a liquid, such as milk, by two Thimonier machines  13  and the pouches  12  are released on a conveyor  14  which forms part of a feed conveyor assembly. A counting device  15  is associated with the conveyor  14  to count the pouches passing by the counter and feeds signals to a controller  16  which counts these. A piston actuated stop gate  17  separates batches  18  of pouches  12  with each batch having a predetermined quantity of pouches and releases the pouches that have been momentarily stopped to a second inclined conveyor  19  which is provided with pusher bars  20  to convey the batches  18  up the inclined conveyor  19 . After a predetermined number of pouches are released on the inclined conveyor, past the stop gate  17 , the stop gate is actuated to start accumulating pouches for a short period of time only sufficient to effectuate a bagging cycle, as will be described later. Accordingly, the stop gate may accumulate only a small portion of the pouches of a batch to separate the batches from one another on their way to the bag filling station  22 . 
     The inclined conveys has side plates  23  to prevent the pouches from falling off the conveyor  19 . It also has a chute  24  at a discharge end of the conveyor  19  to guide the pouches into the open top end  25  of a bag  21  held under the chute, as illustrated in FIG.  3 B. 
     As shown in FIGS. 3 a,    3   b,    3   d  and  3   e,  the chute  24  is provided with a piston operated bottom trap wall assembly  26  which consists of a pair of hinged plates  27  which are secured to a linkage  28  to cause the plates  27  to pivot on their pivot  29  when respective pistons  30  are operated. The pistons  30  are operated by control signals from the controller  16 . The hinge plates  27  close after a batch has been discharged so as to permit the filled bag  21 ″ as shown in FIGS. 1 and 3 b,  to be removed from under the chute  24  and another bag  21  from the series of bags  21 ′ supported on wicket pins  31  to be opened and secured under the trap wall, see FIG. 3 c.  By that time, the chute  24  has accumulated leading ones of the pouches  12  of the next batch  18  of pouches and when the bag is in its open position, a signal is sent to the controller  16  and the trap door assembly is actuated to open the hinge plates  27 . The trap door remains open with the pouches being dumped into the chute and directly into the open bag  21 ′ held thereunder until the last pouch of the next batch is discharged. The trap door assembly then closes and the cycle repeats itself. 
     FIG. 3 c  illustrates the bag opening means and it is of a type well known in the art. It consists of a bag supply formed by a plurality of collapsed bags  21 ′ held on wicket pins  31  and these bags are maintained in juxtaposition. A first one of these bags, filled bag  21 ″, is opened by directing an air jet  32  in the area of the mouth opening  33  thereof to cause the front wall of the bag to move out in the direction of arrow  34 . A bag clamp mechanism  35  moves in to clamp the top edge portion  36  of the filled bag  21 ″ and pull it open in the direction of arrow  34 . A side transfer clamp assembly  37 , as shown in FIG. 3 b,  is operated by a piston  38  and moves in towards the filled bag  21 ″ with the clamp finger  39  in an open position, as shown. It moves over the top side edge  40  of the open filled bag  21 ″ and then clamps a side wall of the bag onto the backing plate  41  to positively engage the side wall of the bag. The bag is then filled with the product and after it is filled the piston  38  is actuated to transfer the filled bag from under the chute  24  with the aid of a transfer conveyor  44 . As described hereinabove, the trap wall  26  is now closed and the next bag is opened and the cycle repeats itself. 
     When the bag engaging and transfer clamp assembly  37  is moved away from of the bag filling station  22 , it rips the filled bag attaching panel  42  from the wicket pins  31 . The piston  38  has a piston stroke sufficient to move the side transfer clamp assembly  37  along the guide rails  43  (see FIG.  4 ), and it moves at the same speed as a transfer conveyor  44  located under the bags  21  so that the filled bag once ripped off its wicket pin is immediately supported on the transfer conveyor and not subjected to a drag force. 
     The side transfer clamp assembly  37  retain the filled bag  21 ″ until it is transferred between a pair of spaced-bag engaging and compression transfer plates  45 , as shown in FIG.  4 . Once the filled bag  21 ″ is positioned between the bag engaging and compression transfer plates  45 , the transfer conveyor  44  is arrested. As shown, the bag engaging and compression transfer plate assembly is comprised by a stationary vertical plate  46  having an inturned support lower ledge  47  and a displaceable vertical plate  48  also provided with a lower support inturned ledge  49 . The displaceable plate  48  is displaceable to and away from the stationary plate  46  by a piston  50  whose operation is again controlled by the controller circuit  16 . The plate  48  is displaced in substantially planar parallel relationship to and away from the stationary plate  46  from a bag receiving position “A”, where the plate  48  is further away, and then to a compression position “B” where the plates are spaced closer to one another to squeeze or compress and support the filled bag  21 ″, such as the bag shown at  51  in FIG. 4, in a compressed state. This sizes the filled bag to enter into the compartment  52  of the case  11  positioned in alignment at the bag receiving position  53 . The plates  46  and  48  are connected to the frame  50 ′ which is displaceable on guide rod  50  to position the plates with a filled bag  51  compressed therebetween over the compartment  52 . The plate  48  is then retracted by the piston  50  to unload the compressed bag  51  in the compartment  52  and the frame  50 ′ is retracted to its bag receiving position, as shown in FIG. 4. A photocell  54  detects the transfer of the filled bag  21 ″ into the compartment  52  of the case  11  and feeds a signal to the controller  16 . The controller  16  then causes a case engaging and displacement mechanism  55 , as shown in FIG. 1, to operate. 
     The description of the case engaging and displacement mechanism  55  will now be described with more specific reference to FIGS. 1,  2 ,  4  and  5 . As shown in FIG. 2, it consists essentially of a rectangular case engaging frame  60 , which is dimensioned to fit inside the case  11 , and in close fit adjacent opposed side walls  11 ′ of the case. The case engaging frame  60  is constituted by opposed top parallel flange walls  61  and two division wall plates  62 . The division wall plates  62  extend below the top flange walls  61  and are dimensioned to fit inside the case close to the bottom wall  11 ″ of the case. The top flange walls  61  have a front flared top portion  61 ′ to guide the compressed bag within the compartments  52  which are formed between the top flange walls and the division wall plates. Of course, depending on the sizes of the bags and the sizes of the cases, there may be only one division wall to form two of the compartments  52  or there could be several division walls  62  to form may compartments  52 . 
     The case engaging frame  60  constitutes a case engaging and displacement means by being secured to a piston actuated indexing frame  64 . As shown in FIG. 5, the case engaging frame  60  is connected to a vertical displaceable support frame  61 ′ which is actuated by a piston  66  which is controlled by the control circuit  16  to cause the frame  65  to move up and down to engage and to disengage from a case  11 . The vertical displaceable support frame  61 ′ is mounted on an indexing frame  66 ′ capable of displacing the case engaging frame laterally at right angles to its vertical displacement. This permits the displacement of the case engaging frame  60 , when engaged with the case, and consequently the case secured thereto to be displaced adjacent the loading position  63  so that each compartment  52  of the case defined by the division plates  62  can be displaced, in sequence, adjacent the loading or bag receiving position  53  to receive a compressed filled bag  51  with pouches therein and to guide the bag inside the case. The case engaging frame  60  remains in the case until all three compartments  52  have been filled. After a case is fully loaded, the case engaging frame  60  is retracted upwardly and the case is released on its transport conveyor  67 . The conveyor  67  is a surface conveyor mounted inside the floor surface  100  and such are well known in the art. Accordingly, cases are fed along this transport conveyor to the case loading machine of the present invention where they are filled and then conveyed away to another station for loading into transport vehicles. 
     As shown in FIG. 4, as the cases are conveyed to the machine  10  of the present invention, the cases  11  are arrested by arresting arms  68  to hold the case at a feed position  80  adjacent the loading station  81 , see FIG. 5. A pair of clamps  69  assures the exact positioning of the case  11  to permit the case engaging frame  60  to be moved thereover and lowered inside the case, as shown in FIG. 2 by arrow  83 . The clamps  69  engage the opposed side walls  11 ′ of the case  11  and release the case once the case engaging frame  60  is in an engaged position. This is controlled by the controller circuit  16 . The piston actuated arresting arms  68  are then withdrawn and repositioned to receive the next case at the feed position. The piston  70  of the indexing frame is then actuated by the controller  16  to position the first compartment  52  at the loading position, see FIG.  4 . After the photocell  54  detects that a filled bag has been loaded, the piston  70  is then actuated to move the case and position the second compartment  52 ′ to the bag receiving position  53 . The third compartment  52 ″ is then displaced at the bag receiving position once the photocell  54  detects the loading of a filled bag in the second compartment. 
     Briefly summarizing the operation of the machine of the present invention, it consists of essentially positioning the case engaging and displacement mechanism  60  in the open top end of a case whereby to segment the case in compartments. The case engaging and displacement mechanism  60  is then displaced by the indexing frame assembly  64  to position the compartments, in sequence, at the bag receiving position  53 . The filled bag  21 ″ at the bag filling station  22  which is filled with small pouches of milk or other liquid, is then displaced by the transfer clamp assembly  37  axially on guide rods or rails  43  and brought between the clamping plate assembly  45  where the filled bag  21 ″, with the unstable liquid pouches therein, is squeezed or compressed to pre-size it and the side transfer clamp assembly  37  is disengaged and returned to the bag filling station to engage another bag. Once positioned over the aligned compartment at the loading position  53 , the plate  48  is retracted and the filled bag  21 ″ falls within the compartment  52  between the division plates  62  and the side walls  11 ′ of the case  11  or between two division plates  62  depending on the location of the compartment  52 . All the compartments  52  are filled in sequence and the case is displaced by the case engaging frame  60  which is secured to the indexing frame. This is done by controlling the piston  70  of the indexing frame and detecting the loading of filled bags within the compartments. After the case is filled, the retracting frame  65  is moved upwardly by actuating piston  66  to release the filled case  11  which is conveyed away on its transport conveyor  67 . 
     As previously described, the method also comprises conveying spaced apart batches of liquid pouches  12  to the control chute  24  for directing the pouches into the open top end  25  of the filled bag  21 ″ held open under the chute. The trap wall  26  of the chute is closed after a batch  18  of pouches  12  have been directed into the open top end of the filled bag  21 ″ whereby to accumulate the pouches  12  of the next batches  18  until the filled bag  21 ″ has been removed from under the chute  24  and a new bag has been engaged in an open position to receive the following batch of pouches. 
     The pouches are released on the conveyor  14 , counted and an accumulation of leading ones of the pouches of a next batch is made prior to being released on the inclined conveyor  19 , whereby the batches  18  are separated from one another. The two Thimonier machines  13  automatically form, fill and seal the milk pouches  12  or pouches containing any beverage or other liquid and these are released on the conveyor  14 . 
     It is within the ambit of the present invention to cover any obvious modifications of the preferred embodiment described herein, provided such modifications fall within the scope of the appended claims.