Patent Publication Number: US-6209293-B1

Title: Packing apparatus for packing multiple layers of containers into a receptacle

Description:
FIELD OF THE INVENTION 
     The present invention relates to a packing apparatus. In particular, the present invention relates to a packing apparatus for packing multiple layers of containers into a receptacle in a preselected pattern. 
     BACKGROUND OF THE INVENTION 
     As part of material handling systems, it is common to pack manufactured products and goods, such as containers, into receptacles, such as a case or a box, for shipment. Typically, the containers to be packed are assembled at a designated packing location and transferred by an automated packing device or similar type of apparatus to the receptacle. The packing device reduces the time and labor costs that would otherwise be required to pack the containers into the receptacle manually. 
     Often, to facilitate packing, the containers at the packing location are prearranged into a pattern before they are picked up and packed into the receptacle. The pattern is selected relative to how the containers will be packed in the receptacle. The prearrangement of the containers into a pattern is commonly used when multiple layers of the same pattern of containers are to be packed into a single receptacle. However, packing devices that rely upon the containers to be prearranged into a pattern before packing are inherently large and costly to operate. They are also limited to packing the containers into the receptacle in the prearranged pattern, rather than having the flexibility to pack the containers in a variety of different preselected patterns. 
     In addition, many packing devices pack the containers by using a technique that simply drops the containers into the receptacle. The dropping technique is inherently unreliable because many of the containers often fall out of position, and can prevent additional containers from being packed in the receptacle. The problems associated with the dropping technique are even more apparent when containers of relatively light weight, such as empty plastic containers, are packed by packing devices. Empty plastic containers are prone to tilt or fall out of position due to their light weight if they are not placed into the receptacle with care. 
     To be effective, the packing of a receptacle requires the containers to be packed with care and precision. This is often difficult to achieve with regularity with most packing devices known in the art, as discussed above. Contributing to the problem of packing containers into a receptacle with precision is the use of plastic liners in receptacles. Plastic liners are used in receptacles such as cardboard boxes to prevent water or moisture from damaging the containers. However, the folds, creases, and excess plastic of the liners often cause the containers in the receptacle to tilt or fall out of position. 
     Accordingly, it is desirable to provide a packing apparatus that can accurately and rapidly pack multiple layers of containers into a receptacle with precision. It is also desirable to provide a packing apparatus that can pack multiple layers of containers into a receptacle in a preselected pattern. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a packing apparatus for packing a plurality of containers delivered to a packing location into a receptacle in a preselected pattern. The packing apparatus includes a placement assembly and a carriage assembly. The placement assembly has a plurality of container pickup devices mounted on one end of a moveable arm. The arm is moveable so that the container pickup devices can pick up the containers from the packing location and transfer them to the receptacle. The carriage assembly includes a moveable carriage that supports the receptacle. The moveable carriage is adapted to move relative to the placement assembly to enable the containers to be placed into the receptacle in the preselected pattern. A system controller is provided for adjustably controlling the timing, sequence, and movement of the carriage assembly and the placement assembly, both individually and relative to each other, to place and pack the containers into the receptacle in the preselected pattern. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For purpose of illustrating the invention, there is shown in the drawings a form which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown. 
     FIG. 1 is a perspective view showing a portion of the packing apparatus according to the invention. 
     FIG. 1A is an isolated view, greatly simplified, of a sensor used in the packing apparatus according to the invention. 
     FIG. 2 is a perspective view of a placement assembly of the packing apparatus, shown relative to a plurality of containers accumulated at a packing location. 
     FIG. 3 is a side elevational view, greatly simplified, of the major parts of the placement assembly shown in FIG.  2 . 
     FIG. 4 is a front view, greatly simplified, of the major parts of the placement assembly shown in FIG. 2, relative to a carriage assembly supporting a receptacle to be packed with the containers. 
     FIG. 5 is a side elevational view of the placement assembly and carriage assembly shown in FIG. 4, illustrating the pick up of the containers from the packing location and the rotation of a portion of the placement assembly to a precalculated placement position. 
     FIG. 6 is a side elevational view of the placement assembly and carriage assembly shown in FIG. 5, illustrating the placement of the containers into the receptacle relative to the precalculated placement position. 
     FIG. 7 is a top view of the receptacle shown in FIGS. 5 and 6, with the containers arranged in a preselected staggered pattern. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings, wherein like numerals indicate like elements, there is shown a packing apparatus  10  for packing multiple layers of containers into a receptacle  11  in a preselected pattern. The invention is discussed herein for an application where the containers to be packed are cylindrically shaped, empty containers  12 , which may be made of plastic material, and the receptacle  11  is a typical cardboard box or carton. However, the packing apparatus  10  is applicable to numerous other types of items, products, or goods that may be packed into a variety of different types of receptacles  11 . 
     Referring to FIG. 1, the packing apparatus  10  of the present invention includes a placement assembly  14 , a carriage assembly  16 , and a system controller  18 . In the illustrated embodiment, the system controller  18  controls the timing, sequence, and movement of the placement assembly  14  and the carriage assembly  16 , individually and relative to each other, to place and pack the containers  12  into the receptacle  11  in a preselected pattern. 
     As shown in FIG. 1, the containers  12  are delivered from a source (not shown) to a packing location  20 , located under the placement assembly  14 . The containers  12  are delivered on a conventionally driven conveyor  22  in a single file, one after each other, moving from left to right as seen in the illustrative figures. Each container  12  has an open top facing upwardly and a bottom which rests on the conveyor  22 . 
     The containers  12  are accumulated at the packing location  20  by a stopping device or bar  24 . The stopping device  24  is situated at the end of the packing location  20  and includes a first rail  26  and a second rail  28 . The first rail  26  extends longitudinally along and parallel to one side of the conveyor  22 . The first rail  26  helps to prevent the containers  12  from falling off the conveyor  22  as they accumulate at the packing location  20 . The second rail  28  is connected to one end of the first rail  26  and extends across the conveyor  22  to prevent the containers  12  from advancing beyond the packing location  20 . As shown, the first and second rails  26 , 28  cause the containers  12  to arrange themselves into a line below the placement assembly  14 . 
     As illustrated in FIGS. 1 and 1A, a sensor  30  is provided along the direction of movement of the conveyor  22 , located toward the rear of the packing location  20 , for sensing when a preselected number of containers  12  have accumulated. The sensor  30  includes a pendulum-type contact member  32  that lies in the path of movement of the containers  12  and is caused to swing in response to contact with each container  12  that is advanced toward the placement assembly  14  by the conveyor  22 . As each container  12  passes the sensor  30 , it will contact and cause contact member  32  to swing out of position relative to the contour of the container  12 , as shown in the isolated view of sensor  30  of FIG.  1 A. After the container  12  passes, contact member  32  will return to its initial position until it contacts another container  12 . By sensing the movement of contact member  32 , the number of containers  12  can be counted. 
     When a preselected number of containers  12  have accumulated at the packing location  20 , no more containers  12  can move past sensor  30 , and thus the contact member  32  will stop swinging. Once the contact member  32  stops swinging, a processor associated with the sensor  30  will generate and relay a status signal to the system controller  18 , indicating that the preselected number of containers  12  have accumulated. Once the status signal is received, the system controller  18  will respond by coordinating the movement of the placement assembly  14  and the carriage assembly  16  to pack the receptacle  11 . Those of ordinary skill in the art will appreciate that other means for determining when the preselected number of containers  12  have been accumulated at the packing location  20  may be used, such as photo sensors, electronic or mechanical counters, and other types of devices, as a few examples. 
     Turning now to FIG. 2, the placement assembly  14  is shown. The placement assembly  14 , which may also be referred to as a placement device, includes a moveable arm or transfer apparatus  34  and a plurality of container pickup devices or suction elements  36 . For illustrative purposes, six container pickup devices  36  are shown, it being understood that any number may be used without departing from the invention. The moveable arm  34  includes a first arm member  38  and a second arm member  40 . 
     The first arm member  38  is pivotably secured to a shift assembly  42  (best seen in FIG. 3) by a pivot mechanism  44 . The shift assembly  42  is provided so that the placement assembly  14  can move both laterally and rotationally to pick up the containers  12  from the packing location  20  and transfer them to the receptacle  11 . The shift assembly  42  is movably secured to a support track  46 , positioned over the packing location  20 . The support track  46  is in the form of a pair of spaced apart rails (best seen in FIG. 2) that extend parallel to the direction of movement of the conveyor  22 . A drive mechanism is operatively connected to the shift assembly  42  so that the shift assembly  42  can move laterally along the rails. The drive mechanism responds to command signals generated by the system controller  18 . 
     The pivot mechanism  44  is provided to allow the first arm member  38  to rotate relative to the shift assembly  42  and the packing location  20 . The pivot mechanism  44  includes a base plate  48  secured to the first arm member  38 . The base plate  48  has a shaft about which the first arm member  38  rotates. In the embodiment shown in FIGS. 2 and 3, the first arm member  38  rotates in a vertical plane perpendicular to the packing location  20 . The rotation of the first arm member  38  may be anywhere between 0° and 180°, although 0° to 90° is presently preferred. For purposes of illustration and discussion only, the first arm member  38  shown in FIGS. 2 and 3 may be considered to be in its full upright vertical position at 0° and is adapted to rotate radially both clockwise and counterclockwise relative to the packing location  20 . Those of ordinary skill will appreciate that the rotation of the first arm member  38  does not have to be within a vertical plane. It is contemplated that the rotation of the first arm member  38  can have any orientation that may be desired, such as horizontally, so that the placement assembly  14  can pick up the containers  12  from the packing location  20 . 
     It should be appreciated that mounting the first arm member  38  to the shift assembly  42  as described above, for lateral movement of the placement assembly  14 , provides several advantages. The shift assembly  42  provides flexibility in the design and location of the components of the present invention, such as the location of placement assembly  14  and packing location  20 . The lateral movement of the placement assembly  14  may be used to eliminate any problems associated with aligning the packing location  20  with the position of the receptacle  11  to be packed. For example, the system controller  18  may be used to maintain the coordinates of the packing location  20  and the coordinates of the position of the receptacle  11  to be packed. As a result, the system controller  18  can move the shift assembly  42  along the support track  46  as necessary, so that the placement assembly  14  can pick up the containers  12  from the packing location  20  and transfer them to the receptacle  11 . As such, the physical position of the packing location  20  and position of the receptacle  11  to be packed can vary and is not limited to the precise arrangement shown in the drawings. 
     As further shown in FIG. 3, the second arm member  40  is both extendable and retractable relative to the first arm member  38  to pick up the containers  12  from the packing location  20  and transfer them to the receptacle  11 . As shown, the second arm member  40  is movably captive within a pair of guide members  50  which depend from the first arm member  38 . Each guide member  50  includes a pair of rollers or bearings positioned on opposite sides of the second arm member  40  so that the second arm member  40  may slide relative to the first arm member  38 . Other means or mechanical devices for permitting the second arm member  40  to move relative to the first arm member  38  may be used. 
     In operation, as the first arm member  38  rotates, it will take with it the second arm member  40  which is held by the guide members  50 . 
     Once the first arm member  38  has been rotated to the desired radial position, the second arm member  38  can be extended or retracted relative to the first arm member  40 . As the second arm member  40  is extended, it will slide along the guide members  50  in a plane generally parallel to the radial position of the first arm member  38 . To retract the second arm member  40 , it is moved upwardly in an opposite direction relative to the first arm member  38 . 
     The movement of both the first arm member  38  and the second arm member  40  is controlled by an actuator  52 . The actuator  52  includes a motor or other form of mechanical device that responds to command signals generated by the system controller  18 . The actuator  52  may include a spring or pulley system that is operatively connected to the first arm member  38  to help it rotate relative to the pivot mechanism  44  of the shift assembly  42 . 
     For example, when the system controller  18  receives the status signal from the sensor  30 , it will respond by activating the actuator  52 . The actuator  52  will rotate the first arm member  38  to its full vertical position at 0°, as illustrated in FIGS. 2 and 3. Next, the system controller  18  causes the actuator  52  to extend the second arm member  40  downwardly so that the container pickup devices  36  can pick up the containers  12  that have accumulated at the packing location  20 . 
     Turning now to FIG. 4, the container pickup devices  36  are shown. The container pickup devices  36  are mounted on one end of the moveable arm  34 . As shown in FIG. 4, the container pickup devices  36  are supported by a support member  53  secured to the lower end of the second arm member  40 . Each container pickup device  36  includes a suction head  54  in pneumatic communication with a suction source  56  via a suction line  58  as shown in FIG.  24 . Each suction head  54  is shaped and dimensioned to engage at least one container  12  at the packing location  20 . In the preferred embodiment of FIG. 4, the suction heads  54  are beveled downwardly, or tapered, to sealably fit within the open top of the containers  12 . 
     As illustrated in phantom in FIG. 4, the container pickup devices  36  are moveable up and down. In operation, the container pickup devices  36  are moved downwardly by the extension of the second arm member  40  relative to the first arm member  38  until each suction head  54  has engaged the open top of at least one container  12 . A compression spring  60  is mounted intermediate the suction heads  54  and the support member  53 . The compression spring  60  absorbs a portion of the downward movement of the second arm member  40  and also urges the suction heads  54  into close contact with the containers  12  so that the suction heads  54  will not damage the container  12  upon engagement and so that a good seal is assured. After the suction heads  54  engage the open tops of the containers  12 , thereby sealing the interior thereof, the system controller  18  will activate the suction source  56  to enable the container pickup devices  36  to pick up the containers  12  through suction. 
     Those of ordinary skill in the art will appreciate that other types of gripping or grasping devices other than suction heads, such as robotic arms, hands, or other mechanically operated devices, may be used to grasp and pick up the containers  12 . Moreover, the suction heads  54  can be shaped to pick up any type of container  12 , including containers that are filled and have a lid or top secured thereto. 
     Once the suction source  56  is activated and suction is created, the actuator  42  will retract the second arm member  40  upwardly relative to the first arm member  38  to clear the packing location  20 . As a result, the container pickup devices  36  will pick up or lift the containers  12  from the conveyor  22 , holding them by suction. As the second arm member  40  clears the packing location  20 , another set of containers  12  will begin to accumulate at the packing location  20 . 
     The suction created in the container pickup devices  36  may also be advantageously used to detect defects in the containers  12 . A sensor may be provided that measures the flow rate of air drawn in by the suction source in each container pickup device  36 . The sensor may generate and relay a signal to the system controller  18  relative to the flow rate. The system controller  18  may then calculate and maintain a running average of the flow rate of the container pickup devices  36 , which may be used, in turn, to measure the flow rate in each suction head  54 . If the flow rate of any particular container pickup device  36  exceeds a certain level above the average, the system controller  18  may generate a condition signal that identifies the container pickup device  36  on a display. In turn, the condition signal may be used to indicate that the container pickup device  36  did not properly seal or engage the container  12  or to indicate that the container  12  is defective. Devices to measure the airflow or suction as discussed above are known in the art, and are available from several manufacturers. 
     As further shown in FIG. 4, the carriage assembly  16  is situated below the placement assembly  14 . Preferably, the carriage assembly  16  is angled relative to the placement assembly  14  or to the horizontal so that it has a lower end underneath a portion of the packing location  20 , as seen in FIGS. 4 and 5. The angle of the carriage assembly  16  facilitates the placement, packing, and arrangement of the containers  12  in the receptacle  11 , as discussed in more detail below. Although any angle may be chosen, 20° is presently preferred. 
     The carriage assembly  16  includes a moveable carriage  62  that supports the receptacle  11 . The carriage  62  includes a pair of wheels  63  adapted to travel on a support assembly or track  64  having a pair of spaced apart rails that extend underneath a portion of the placement assembly  14 (see FIGS.  4  and  5 ). An actuator  66  located toward the rear of the track  64  controls the movement of the carriage  62 . The actuator  66  includes a drive or a motor mechanically coupled to the carriage  62  by an adjustable length mechanism  68 , such a threaded shaft as shown in FIG.  4 . In operation, the motor will rotate the shaft in a first direction to cause the carriage  62  to move downwardly on the track  64  to a position underneath the placement assembly  14 . When the motor is reversed, the carriage  62  will move in a second direction away from the placement assembly  14 . The timing, sequence, and movement of the carriage  62  by the actuator  66  is controlled by the system controller  18  to enable the carriage  62  to accurately position the receptacle  11  to receive the containers  12 . 
     FIG. 5 shows a portion of the packing apparatus  10  to illustrate the packing of the containers  12  into the receptacle  11 . As shown and discussed above, the carriage assembly  16  is disposed preferably at a 20° angle relative to the horizontal. The placement assembly  14  is in the full upright vertical position. With the placement assembly in the vertical position, the second arm member  40  of the placement assembly  14  is extended downwardly (shown in phantom) and retracted upwardly to pick up the containers  12  at the packing location  20 . Next, the first arm member  38  of the placement assembly  14  is rotated clockwise, taking with it the second arm member  40 . The first arm member  38  is rotated so that the containers  12  supported by the second arm member  40  clear the packing location  20  (also shown in phantom). The degree of rotation of the first arm member  38  is selected by the system controller  18 , relative to a precalculated placement position. 
     The precalculated placement position is calculated by the system controller  18 . The system controller  18  will maintain data relative to the dimensions of the receptacle  11  (such as the length, width, and height) and the dimensions of each container  12  (such as the diameter, cross-section, and height). The way in which the system controller  18  may be programmed to receive, store, and process such data is well within the skill of the ordinary artisan and need not be described in detail. Based upon this data, the system controller  18  will calculate the number of rows, columns, and/or layers of containers  12  that may be packed into the receptacle  11 . In accordance with these calculations, the system controller  18  will coordinate the movement of the placement assembly  14  and the carriage assembly  16  to pack the receptacle  11  with a preselected number, rows, layers, and pattern of containers  12 . 
     Turning now to FIG. 6, the placement and packing of the containers  11  into receptacle  11  is shown. To pack the receptacle  11  shown in FIG. 6 with a preselected number of rows and layers of containers  12 , the system controller  18  positions the carriage  62  on the track  64  relative to the precalculated placement position. For purposes of describing the packing process, the first containers  12  placed into the receptacle  11  form a “first” row. The angle of the carriage  62  will cause the first row of containers  12  to lean against the inner surface of the wall of receptacle  11 . In this way, the containers  12  will not fall or move out of position. 
     To place the containers  12  into the receptacle  12 , the second arm member  40  is extended downwardly to the precalculated placement position, as illustrated in FIG.  6 . After the second arm member  40  has been extended, the system controller  18  will deactivate the suction source  56 . By deactivating the suction source  56 , the suction created in the pickup devices  36  will begin to decrease so that the suction heads  54  will release the containers  12  after the containers  12  are properly positioned within the receptacle  11 . Preferably, air jets associated with each container pickup device  36  are used to facilitate the release of the containers  12 . The air jets are in communication with a source, such as an air compressor, that is under the control of the system controller  18 . In operation, once the carriage assembly  16  and the placement assembly  14  have moved the container pickup devices  36  into proper position relative to the precalculated placement position, the system controller  18  will activate the compressor. Once the compressor is activated, the air jets will emit a stream or blast of air under pressure to cause each container  12  to disengage from the suction heads  54 . The use of air jets or similar devices permits rapid release and placement of the containers  12  into the receptacle  11 , which may be necessary if it takes too long for the suction in the suction head  46  created by the suction source  56  to sufficiently decrease to release the containers  12  at the time of placement. 
     To place the next succeeding row of containers (i.e., a “second” row), the system controller  18  will cause the placement assembly  14  to pick up the containers  12  accumulated at the packing location  20  and transfer them to the receptacle  11 , as previously described above. Prior to the containers  12  actually being placed in the receptacle  11 , the system controller  18  will incrementally move the carriage  62  downwardly on the track  64  (toward the right as illustrated in FIG. 6) to position the receptacle  12  relative to the precalculated placement position. After the carriage  62  has been moved and is in the proper position, the placement assembly  14  will place the containers  12  into the receptacle  11  at the precalculated placement position to form the second row. 
     The angle of the carriage  62  on the carriage assembly  16  will cause neighboring rows of containers  12  to lean against each other. In that way, each container  12  will remain in position and will not interfere with the placement of incoming containers  12 . Of course, the angle of the carriage assembly  16  may be eliminated, such that the carriage  62  will move in a plane under the placement assembly  14  that is generally parallel to the horizontal. If the angle is eliminated, the placement assembly  14  will have to move to an extent sufficient not only to clear the packing location  20  but also to place the containers  12  into the receptacle  11  positioned underneath. 
     With further reference to FIG. 6, the system controller  18  will move the carriage assembly  16  and the placement assembly  14 , relative to each other, until the last or “nth” row of containers  12  is packed into the receptacle  11  which, in turn, forms a first layer of containers  12 . After the last row is packed, the carriage  52  is moved upwardly on the track  64  (to the left as illustrated in FIG. 6) so that a “first” row of a “second” layer of containers  12  may be placed into the receptacle, in the same way the first row of the first layer of containers  12  was placed. This process may be repeated for as many layers as necessary or desired to fill the receptacle  11 . After the receptacle  11  is packed with the preselected number of rows and layers of containers  12 , the system controller  18  will move the carriage  62  on the track  64  to a location where the receptacle  11  can be removed either manually or is transferred onto a discharge conveyor  70 . As seen in FIGS. 5 and 6, the discharge conveyor  70  has an end located approximate the lower end of the track  64  which lifts the end of the receptacle  11  from the carriage  62  and conveys it upwardly to clear the packing apparatus  10 . 
     Those of ordinary skill will appreciate that the packing apparatus  10  of the present invention is flexible enough to permit the containers  12  to be packed into the receptacle  11  in a variety of preselected patterns. As one example, the packing apparatus  10  may be used to pack the receptacle  11  with containers  12  arranged in a staggered pattern. To pack the staggered pattern, the system controller  18  will shift or move the shift assembly  42 , and thus move the first arm member  38 , laterally along the support track  46 , before the containers  12  are placed into the receptacle  11 . The first arm member  38  will be moved laterally to offset the position of the containers  12  to be placed into the receptacle  11  relative to those already placed therein and relative to the precalculated placement position. As illustrated in FIG. 7, the second row of containers  12  will be staggered traversely with respect to the first row of containers  12 . Moreover, each of the containers  12  of the second row will be nested within a valley formed by two neighboring containers  12  of the first row. The nesting of the containers maximizes the space available within the receptacle  11  for packing the containers  12 . To place the next row (i.e., “third” row) of the staggered pattern, the first arm member  38  is returned to its initial position so that the containers  12  will be placed at or relative to the precalculated placement position. To pack the receptacle  11  with a first layer of staggered rows, every other row will be offset as described above and illustrated in FIG.  7 . 
     In the preferred embodiment, the system controller  18  will move the carriage  62  in both a first direction and a second direction prior to placing the containers  12  into the receptacle  11 . The carriage  62  will be moved in the first direction to a point below the precalculated placement position. Moving the carriage  62  in this manner will ensure that the containers  12  already placed in the container do not interfere with incoming containers  12 . However, just prior to placing the row of containers  12  into the receptacle  11 , the carriage  62  is moved in the second direction opposite to the first direction so that the containers  12  are placed at the precalculated placement position. Moving the carriage  62  in the second direction advantageously shifts any containers  12 , already placed into the receptacle  11  and that have moved, into the proper preselected pattern. Indeed, moving the carriage  62  in the first direction and the second direction, in addition to the angle of the carriage assembly  14 , facilitates the proper arrangement and placement of the containers  12  in the receptacle  11 . 
     As further shown in the preferred embodiment of FIGS. 1,  5 , and  6 , the packing apparatus  10  includes a hold-down assembly  72 . The hold-down assembly  72  is provided to hold down the flaps that may be associated with the receptacle  11 . Those of ordinary skill will appreciate that keeping the flaps of a receptacle  11 , such as a box, down or out of the way during packing is often difficult. The hold-down assembly  72  helps to eliminate this problem. 
     As best seen in FIG. 1, the hold-down assembly  72  includes a pair of adjustable height support members  74  located on each side of the track. Because each pair of support members  74  mirrors the other, the remaining components of the support members  74  will be hereinafter described as being representative of both. 
     Each support members  74  includes a first member  76  moveably disposed within a second member or base  78 . The first member  76  is adapted to move up and down relative to the second member  78 . An arm  80  is secured to the adjacent first members  76 . For purpose of this description only, the portion of the arm  80  attached to the first member  76  situated closest to the packing location  20 , will be referred to hereinafter as a “first end”. The portion of the arm  80  attached to the first member  76  furthest from the packing location  20 , will be referred to hereinafter as the “second end”. 
     An actuator  82  is secured to the first end of the arm  80 . The actuator includes a pressure cylinder in fluid communication with a pressure source via a flow line. The cylinder includes a shaft  91  having one end operatively connected to the first end of the arm  80  relative to the second end. As the cylinder is pressurized, shaft  91  extends to raise the first end of the arm  80 . To lower the arm  80 , the cylinder can be pressurized in the opposite direction to retract the shaft  91 . 
     Togther, each of the arms  80  support opposite sides of a plurality of rollers  84 . The rollers  84  are provided to make light contact with the top edge of the receptacle  11 , in order to hold the flaps down. Each roller  84  is journaled at different locations into a plurality of holes provided within the arms  80 . As illustrated in FIG. 1, the rollers  84  are not evenly spaced. One roller  84  is located downstream (i.e., proximate the first end) and the other is located upstream (i.e., proximate the second end). Although three rollers  84  are shown, any number of rollers  84  may be used. 
     In operation, the system controller  18  will pressurize the cylinder to raise the first end of the arms  80 . As the first end of the arms  80  are raised, the system controller  18  will move the carriage  62  of the carriage assembly  16  into position so that the placement assembly  14  can place the containers  12  into the receptacle  11 . After the carriage  62  has moved into position so that the first row of containers  12  can be placed, the system controller  18  will cause the actuator  82  to retract the shaft to lower the arms  84 . The arms  80  are lowered until the rollers  84  make light contact with the top edge of the receptacle  11 . Flap rollers  93  may be used with receptacles  1  with the flaps up. 
     In an alternative embodiment, a photo sensor may be used to sense when the receptacle  11  on the carriage  62  is in position. The photo sensor will generate and relay a stats signal to the system controller  18 . The system controller  18  will respond to the status signal from the photo sensor to pressurize the cylinder of the actuator  82  to raise and lower the arm  84 , as described above. 
     In an alternative embodiment, the carriage  62  may also include a pair of oppositely disposed rollers  86 , as best seen in Figure land  4 . The rollers  86  are mounted on a support that is secured to the carriage  62  and help to guide the location of the receptacle  11  on the carriage  62 . The rollers  64  may also be advantageously used be used to hold down the bottom end of the flaps or carton down members associated with receptacles  11  so the flaps will not interfere with the packing of the receptacle  11 . 
     In an alternative embodiment, the carriage  62  may be associated with an additional suction device (not shown). This particular suction device may be used to draw excess air that may form between plastic liners and the inside of the receptacles. This will reduce the air pockets that otherwise form when plastic liners are used. Such air pockets have a tendency to form folds and creases in the plastic liners which may cause the containers  12  placed into the receptacle  11  to fall or tilt out of position or into the path of incoming containers. 
     In yet another alternative embodiment, a receptacle  11  in-feed assembly  88  may be used, as shown in FIGS. 5 and 6. The in-feed assembly  88  is used to support empty receptacles  11  that will be transferred to and received by the carriage  62 . As shown, the in-feed assembly  88  has an end  90  in communication with the track  64  of the carriage assembly  16 , and is also disposed at an angle to the horizontal. In operation, an empty receptacle  11  is received in the in-feed assembly  88  and awaits the carriage  62 . After the carriage  62  has delivered a packed receptacle  11  to the discharge conveyor  70 , it will move upwardly on the track  64  to the in-feed assembly  88 . Once the carriage  62  comes into close proximity with the end  90  of the in-feed assembly  88 , the empty receptacle  11  is released and received in the carriage  62 . After the empty receptacle  11  is received in the carriage  62 , the carriage  62  is moved into position by the system controller  18  to receive the containers  12  as previously described. 
     Persons skilled in the art will recognize that there may be different devices, mechanisms, and methods of operation which are within the spirit and scope of the invention as defined in the claims. Also, it should be understood that the drawings, while useful in illustrating the invention, are not intended to be necessarily to scale. The dimensions and relative sizes and locations of the various parts shown can be varied, depending upon the particular receptacle  11  being packed, the size and dimensions of the containers  12 , and the like, without departing from the scope of the invention. To the extent that the drawings imply dimensions and relative size positions, the drawings should be regarding as illustrative only and not limiting the invention to particular dimensions, sizes, position, and location of parts. 
     Finally, the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention.