Abstract:
A packaging system for pillow bags containing coffee or other consumable products which generate gases includes a container assembly into which a triangular shaped insert is positioned to reduce the space at the top portion of the container. The insert prevents excessive swelling in the headspace of the bags and also reduces damages occurring to the bags by eliminating movement of the bags in the container during transport.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a packaging system for ventable product containing bags equipped with degassing relief valves and, more particularly, to a packaging system in which a container assembly for shipping such bags includes a removable insert for reducing space at the top portion of the container and minimizing damage during shipping and handling of such bags. 
     BACKGROUND OF THE INVENTION 
     As an alternative to cans, products which generate gases, typically either roasted and ground coffee or roasted whole bean coffee, are often packaged in soft packages without applying a vacuum; these packages are typically known as pillow bags. Pillow bags are desirable in that they are easier to handle and more lightweight than cans and, as the product is used, the bags may be compressed to reduce the amount of space needed to store them. However, there are several drawbacks associated with pillow bags. 
     One problem with pillow bags is that newly packaged coffee tends to generate a mixture of gases inside the bag, mainly carbon dioxide, which causes the bag to become swollen and eventually burst, rendering the package unsellable. This problem has been ameliorated to some degree by the inclusion of a degassing valve in the bag which releases gas from the bag when a certain internal pressure is reached. The valve then closes when pressure returns to an acceptable level. Such valves are disclosed, for example, in U.S. Pat. No. 5,515,994 to Goglio and U.S. Pat. No. 4,000,846 to Gilbert. The design of these valves is typically such that the bag must completely fill with gas before sufficient internal pressure is reached to open the valve. Since such bags must necessarily have a headspace, i.e., a space within the bag above the product, and since the bags can freely expand, the headspace will fill with gas, giving it a swollen appearance by the time it is placed on the shelves of a retail store. This swollen appearance tends to be very undesirable to the consumer. 
     Another problem that is encountered with pillow bags is that because the bags are packaged in containers, such as rectangular boxes held closed with tape, adhesive or the like, there is a likelihood that if a knife is used to open the container, one or more bags may inadvertently be cut, rendering them unsellable. Still another problem is that since the bags are generally packaged such that they do not completely fill the container, they may bounce freely within the container during shipping and handling, causing cracks and holes to form in the bag film, allowing air to leak into the bags. The oxygen in this air causes staleness in the product long before the intended shelf-life has expired. 
     Accordingly, the need exists for a packaging system for ventable pillow bags containing gas generating products which reduces the amount of gas build-up in the headspace of the bags and prevents damage to the bags during shipping and handling. 
     SUMMARY OF THE INVENTION 
     Thus, it is a purpose of the present invention to provide improvements which overcome the above described disadvantages of existing packaging systems for ventable pillow bags. 
     In accordance with a preferred embodiment of the invention, the packaging system includes a container assembly comprising a container, an insert and the pillow bags themselves. The container is designed to receive a plurality of ventable pillow bags containing a product of the type which generates gases, each of the bags having a headspace at the top thereof which is expandable to accommodate such gases, as well as a valve for venting the gases when pressure in the bag reaches a predetermined level. The insert reduces available space in the container, thereby reducing expansion of the headspace and minimizing damage to the bags during shipping and handling. 
     In another preferred embodiment of the invention, a container assembly for holding a plurality of ventable bags containing a gas generating product includes a container having a bottom wall, a pair of opposite side walls, a pair of opposite end walls, an open top end and a closure member for closing the top end. The bags are receivable in the container such that the bottom ends are positioned along the bottom wall. The container assembly further includes at least one insert of triangular cross-section, said insert preferably comprising a rectangular shaped sheet of material folded to form two parallel folds therein forming the triangular shape. The insert extends generally between end walls adjacent the top of the container such that a base of the triangular shape is positioned closest to the closure member and an apex is directed downwardly to create a triangular-shaped separation between the tops of the adjacent rows of bags to thereby reduce available space at the top of the container for expansion of the headspace of the bags. Preferably the insert is removable and the container is a rectangular shaped box. 
     It is, therefore, an object of the present invention to provide a packaging system for pillow bags containing a gas generating product which reduces expansion of the headspace in the bags during shipping and storage. 
     It is another object of the invention to provide a container assembly for packaging such bags which reduces the risk of the bags being damaged when the container is opened with a knife or other sharp instrument. 
     It is yet another object of the invention to provide a container assembly which reduces movement of such bags packaged therein to thereby lessen the chance of damage to the bags during shipping and handling. 
     These and other objects of the present invention will become apparent from the detailed description to follow. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     There follows a detailed description of the preferred embodiments of the invention which are to be taken together with the accompanying drawings, wherein: 
     FIG. 1 is a perspective view with a partial cut away of the packaging system of the present invention; 
     FIG. 2 is a perspective view of the insert of FIG. 1; 
     FIG. 3 is a perspective view similar to FIG. 1 but with the insert removed; 
     FIG. 4 is a cross-sectional view through line  4 — 4  of FIG. 1, but with the top of the container closed; and 
     FIG. 5 shows the top of a pillow bag with a gas filled headspace. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the figures, like elements are represented by like numerals throughout the several views. 
     FIG. 1 shows the packaging system  1  of the invention which includes a plurality of pillow bags  2  and a container assembly  3  which includes a container  4  and an insert  5 . Bags  2  contain a consumable product of the type which generates gases when packaged in a sealed, airtight container. The primary products contemplated for use with the invention are roast and ground coffee and roast whole bean coffee. After product is added to the bags  2 , they are vacuumed, gas flushed and sealed at the top such that 4% or less oxygen is contained in the headspace of the bag. However any product which develops a gas during storage is within the contemplation of the invention. Initially, the headspace in the bags is minimal, with the sides of the bag close together at the top, as shown in FIGS. 1,  3  and  4 . Note the small headspace  17  in FIG.  4 . This is in fact the bag appearance that the customer finds most desirable. Bags  2  are fitted with degassing one way valves  6  which allow gases which develop in the bags  2  to escape when pressure in the bags  2  reaches a predetermined level. For example, where the product contained in bags  2  is coffee, carbon dioxide will typically be generated during shipping and storage. However, the valves  6  allow the gases to build up a substantial amount before venting starts. At an opposite extreme, the headspace  17  of a bag  2  could expand substantially, as shown at FIG. 5, thereby giving the bag a swollen appearance which the customer would find undesirable. Once opened, the bags may be re-closed at the top using conventional means. 
     Container  4  has a bottom wall  7 , opposite side walls  8 , opposite end walls  9 , an open top  10  and a closure structure for sealing the open top  10 . In the preferred embodiment, the container  4  is a rectangular shaped box constructed from corrugated paper board. Other materials of construction may also be utilized. The closure structure is generally in the form of two end flaps  13  which are first folded down and two side flaps  12  which are then folded over end flaps  13 . The width of each of side flaps  12  are preferably half the width of end walls  9  such that they meet at the center line of the container. Container  4  may then be sealed by an adhesive which secures flaps  12  onto flap  13  or by placing a strip of tape (not shown) over the adjoining edges  21  of side flaps  12  along the center line. Other closure means are, of course, within the contemplation of the invention. 
     The container assembly  3  further includes at least one insert  5  which is placed at the top of the container  4 . In the preferred embodiment as shown, container  4  is designed to receive two adjacent rows of bags  2 , such that only a single insert  5  is needed. However, if container  4  is sized to receive additional rows of bags  2 , additional inserts  5  may be incorporated into container  4 , with each insert  5  being seated between adjacent rows of bags  2 . 
     Insert  5  should be sufficiently rigid to maintain its shape. A solid block of any material, e.g., a lightweight Styrofoam material. However, in a preferred embodiment, insert  5  is formed from a single rectangular sheet of material such as corrugated cardboard. As shown in FIG. 2, the preferred shape of insert  5  is triangular such that a single piece of cardboard is pre-folded along two lines to form an apex  16 , a base  14  and two side walls  15 , with the side walls  15  being of substantially the same dimensions. It is also possible to fold the rectangular sheet only once and thereby form an apex  16  and two side walls  15 , eliminating base  14  such that a V-shape, instead of a triangular shape, is formed. However, this structure is less desirable, as base  14  tends to keep side walls  15  from collapsing inwardly in the container  4  as headspace  17  in the bags  2  expands. Width B of the base  14  is substantially the same as the width of end walls  9  and length A of the base  14  is approximately the same as that of side walls  8  such that the open top  10  of the container  4  is substantially completely covered. 
     FIG. 3 shows the packaging system  1  before insert  5  has been placed in container  4  and before gases have expanded the headspace  17  in the bags  2 . At this time, referring also to FIG. 4, the product  19  within the bags  2  does not come up to the top of the bag  2 . Rather, it leaves a headspace  17  above the product. Referring to FIG. 3, the top portion of container  4  is much larger than the room now taken up by the tops of bags  2  at their headspaces  17 . Without the insert  5 , gas generation in the bags prior to venting through valves  6  could cause the headspaces of bags  2  to swell and fill much of the space at the top of the container as shown in the extreme in FIG. 5. A certain amount of gas is desirable in headspaces  17  as the gas contains the aroma which is released upon opening the bags  2 . However, as noted above, valves  6  are typically designed to allow headspace  17  to completely swell up before allowing any release of gases. 
     As shown in FIG. 4, insert  5  reduces the amount of space available at the top of the container  4  into which the headspaces  17  of bags  2  may expand. Maximum internal pressure in headspaces  17  is thereby reached before headspaces  17  actually become completely filled with gas so that valves  6  open to release the pressure and the bags  2  do not fully swell. 
     Besides preventing bags  2  from becoming swollen, insect  5  also protects bags  2  from being cut if container  4  is opened with a knife or other sharp object as is typically the case. As noted above, panels  12  of closure means  11  are typically sealed by adhesive to inside panels  13  or adjoining edges  21  are closed against panels  13  by a strip of tape extending between opposite end walls  9 . Because insert  5  also reduces the available space at the top of container  4 , it also reduces movement of bags  2  in container  4  which helps to prevent damage to bags  2  such as cracks and holes which can occur when bag packages are moved about within the container  4  during shipping and handling. 
     EXAMPLE 
     In order to test the effectiveness of the packaging system of the invention, container assemblies having bags of coffee contained therein were subjected to 40 minutes of ASTM Standard Loose Load vibration using different container orientations to simulate shipping conditions. Containers having coffee bags therein without an insert were tested using the same method to provide a standard of comparison. Before conducting the vibration testing, all coffee bags were examined to ensure that the valves were properly sealed. Only bags having 4% or less oxygen content in the headspace, considered as being of a good quality, were subject to vibration. The results of the testing is provided in the table below. 
     
       
         
               
             
               
               
             
               
               
               
             
               
               
               
               
               
             
           
               
                   
               
               
                 LEAKERS AFTER VIBRATION 
               
             
          
           
               
                 Container 
                 Number and Percent Flex Cracks 
               
             
          
           
               
                 Orientation 
                 Normal Container 
                   
               
               
                 During Vibration 
                 (without insert) 
                 Container with insert 
               
               
                   
               
             
          
           
               
                 Right side up 
                  4 out of 48 
                  8% 
                  0 out of 48 
                  0% 
               
               
                 Upside down 
                 18 out of 18 
                 100% 
                 21 out of 48 
                 44% 
               
               
                 Laying on face 
                 14 out of 24 
                  58% 
                  0 out of 24 
                  0% 
               
               
                   
               
             
          
         
       
     
     As can been seen from the results, the insert helped to substantially reduce pinholing and flex cracking in the bags, even in the unusual circumstance where the containers were turned upside down. 
     Although the invention has been described in considerable detail with respect to the preferred embodiments thereof, variations and modifications will be apparent to those skilled in the art without departing from the spirit and scope of the invention, as set forth in the claims.