Patent Publication Number: US-2012023709-A1

Title: Reusable, autoclaveable closure device for a flexible bag

Description:
The present application claims the benefit of prior filed U.S. Utility application Ser. No. 11/965,650, filed 27 Dec. 2007, which in turn claimed the benefit of U.S. Provisional Patent Application No. 60/882,458, filed 28 Dec. 2006, to which applications the present application is a continuation-in-part, and which applications are incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention is in the field of closures for flexible bags. More specifically, the present invention relates to sterilizeable and reusable closures having elongated clamping elements for sealing flexible bags. 
     BACKGROUND OF THE INVENTION 
     Sealable flexible bags are known in the field. More specifically, sterilizeable and reusable closures having elongated clamping elements for sealing flexible bags are known. 
     Various methods and apparatus have been developed through the years for the cultivation of mushrooms. Most commonly, bottles and bags are used for cultivating mushrooms. Bag cultivation, however, has several advantages over bottle cultivation. It is an economic means of production, as well as a means for producing practically any variety of mushroom. Bag cultivation also allows for flexibilty in crop production. 
     A benefit of the present bag clamp is that it can seal the opening of a bag, and eliminate the need for a flexible bag sealing machine with its problems. In particular, the present bag clamp is a reusable, simple design, which allows both the bag and the clamp to be easily reused and autoclaved. In the mushroom cultivation field, this combination can allow easy verification of the internal CO 2  content of a bag without having to cut the bag open. 
     In view of these considerations, it would be beneficial in the field to have a flexible bag closure device that allows for multiple sterilizations without substantially losing its intended resilience properties, and also allow easy verification of the internal CO 2  content of a bag without having to cut the bag open. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a sterilizeable, reusable flexible bag closure device having the utility of certain typical prior bag closure devices, but without certain of their disadvantages. More specifically, the present flexible bag closure device is intended to avoid the disadvantage of one time use by using materials which are capable of multiple sterilizations without substantially losing its intended resilience properties. 
     The present invention is a sterilizeable, reusable flexible bag closure device for closing an open end of a flexible bag. The closure device comprises two primary structural components: an elongated clamp member and an elongated rod member. In use, the open end of the flexible bag is folded around the elongated rod member. The combination of the rod member with the bag end folded over the rod member is then installed into the interior space of the clamp member. 
     The present bag closure device provides a resilient, reusable closure device intended for use in applications wherein the bag with the closure device attached (to close and seal the open end of the bag) are subjected to a sterilization process. Therefore, it is an important feature of the present device that it is made of materials capable of being subjected to multiple sterilizations without substantially losing its intended resilience properties. Additionally, the closure device is easily removable to allow the bag to be reopened in its original condition (i.e., without the bag being damaged, destroyed, or otherwise physically altered by the closure and reopening process). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A and 1B  are end views of the present sterilizeable, reusable closure for use on a flexible bag showing the relationship of the rod member, bag wall and clamp member before (A) and after (B) attaching the closure device to the open end of the bag. 
         FIG. 2A  is a perspective view of the clamp member and rod member of the present sterilizeable, reusable closure. 
         FIG. 2B  is an end view of the present sterilizeable, reusable closure illustrating the free space within the interior space of the clamp member with the rod member received therein. 
         FIG. 3  is a top view of the present sterilizeable, reusable closure in use to close the open end of a flexible bag. 
         FIGS. 4A and 4B  are a perspective views of an alternative embodiment of the present invention showing the clamp member and the rod member joined by a pivotable linkage. 
         FIGS. 5A and 5B  are plan views of alternative embodiments of the clamp and rod members of the present invention. 
         FIG. 5C  is an end view of an alternate embodiment of the rod member of the present invention. 
     
    
    
     DESCRIPTION OF THE INVENTION 
     The present invention is a sterilizeable, reusable flexible two-piece bag closure device for closing an open end of a flexible bag. The present bag closure device is intended for use in applications wherein the bag with the closure device attached (to close and seal the open end of the bag) are subjected to a sterilization process. An example of such application is the autoclaving of closed flexible plastic bags and their contents in the mushroom growing industry. Therefore, it is an important feature of the present device that it is made of materials capable of being subjected to multiple sterilizations without substantially losing its intended resilience properties. It is also an object of the present invention that the closure device be easily removable to allow the bag to be reopened in its original condition (i.e., without the bag being damaged, destroyed, or otherwise physically altered by the closure and reopening process. 
     A benefit of the present bag clamp is that it can seal the opening of a bag, and eliminate the need for a flexible bag sealing machine with its problems. In particular, the present bag clamp is a reusable, simple design, which allows both the bag and the clamp to be easily reused and autoclaved. In the mushroom cultivation field, this combination can allow easy verification of internal CO2 content of bag without having to cut the bag open. 
     Referring now to the drawings, the details of preferred embodiments of the present invention are graphically and schematically illustrated. Like elements in the drawings are represented by like numbers, and any similar elements are represented by like numbers with a different lower case letter suffix. 
     As noted above, the present invention is an autoclave sterilizeable and reusable flexible bag closure device  10  for closing the open end(s)  22  of a flexible bag  20 . See  FIGS. 1A and 1B . The present closure device  10  comprises two primary structural components: an elongated clamp member  12 , and an elongated rod member  16 . In use, the open end  22  of a flexible bag  20  is folded around the elongated rod member  16 . The combination of the rod member  16  with the open end  22  folded over it is then installed into the interior space  30  of the clamp member  12 . 
     The closure device is intended for use with a flexible bag in an autoclaving process, where the sterile integrity of the content of the bag is important Therefore, the clamp member  12  has a clamp length Lc substantially at least as long as the width W of the open end of the bag  20  to be closed. This width W of the open end  22  of the bag  20  is taken with the open end  22  flat. The clamp member  12  has a “C”-shaped structural cross-section (see  FIG. 1 ) defining an interior space  30 . The interior space  30  has a cross-section with an interior space inside diameter/D. Also as seen in the cross-section, the clamp member has aims or jaws  34  that are resilient, i.e., are flexible and have memory. The arms  34  frame the side-opening  38  along the length Lc of the clamp member  12 , see  FIG. 2A . The clamp member  12  also has at least one end-opening  40 . 
     The“C”-shaped cross-section of the clamp member  12  has an arc A of greater than 180 degrees and less than about 280 degrees. The degree of arc A is sufficient to enable the clamp member  12  to closely receive and compressively hold the rod member  16  when the rod member  16  has a section of the flexible bag  20  disposed around it, and is received within the clamp interior space  30 . 
     The rod member  16  has a rod length Lr that, substantially, is at least as long as the width W of the open end  22  of the bag  20  to be closed. Also, the rod member  16  has an outside rod diameter OD smaller than the ID of the clamp interior space  30 . The rod member  16  is loosely receivable into the interior space  30  of the clamp member  12  as illustrated in  FIG. 2B . The rod member  16  can be hollow (i.e., tubular) as in  FIG. 1A , or solid as in  FIG. 1B . 
     When the rod member  16  is received into the interior space  30  of the clamp member  12 , there is a free space distance Df between the outside rod surface  50  and the inside surface  32  of the clamp interior space  30 . The free space distance Df represents the average distance between the rod OD and the clamp ID when the rod member  16  is received in the center of the interior space  30 . The free space distance Df is disposed to allow the interior surface  32  of the arms  34  to closely (i.e., compressively) receive at least one thickness T of the flexible bag  20  between the interior surface  32  of the clamp interior space  30  and the external surface  50  of the rod member  16 . 
     The rod member  16  may be inserted into the clamp member  12  by inserting the rod member  16  with the open end  22  wrapped around it into the clamp member  12  through the clamp gap  38  disposed along the length Lc of the clamp member  12 . For example see  FIGS. 1A and 1B . Alternatively, the rod member  16  may be inserted into the clamp member  12  by inserting the rod member  16  with the open end  22  wrapped around it from the open clamp end  40  of the clamp member  12  as exemplified in  FIG. 2A . That is, the rod member  16 , with the open end  22  wrapped around or folded over it (not shown), can be inserted into the clamp member  12  from an open end  40  of the clamp member  12 . 
     In either case, the resilient arms  34  of the clamp member  12  compress against the section of the bag  20  received in the interior space  30  of the clamp member  12  as illustrated by the small arrows in  FIG. 1B . Compression of the material of the bag  20  closes and seals the open end  22  of the bag  20  without damaging or substantially altering the original condition of the bag  20 . Similarly, removal of the closure device  10  does not damage or substantially alter the condition of the bag  20 . 
     In a preferred embodiment as illustrated in the figures, the bag closure device  10  of is made of a reusable sterilizable material. Preferably, the bag closure device  10  is made of a semi-rigid material which can withstand the heat and pressure of an autoclave. For example, a metal material, such as stainless steel or brass, is readily available and useful for the present device  10 . Other suitable materials, such as autoclaveable plastics, are known to and are selectable by one of ordinary skill in the art for practice in the present invention. In another embodiment, the bag closure device  10  is made of a chemically sterilizable material. 
     Additionally, in an alternative preferred embodiment, one or both arms  34  of the clamp member  12  can have a guide finger  42  extending from it to form a lip along the length of the gap  38 . See  FIG. 1B  and  FIGS. 2A and 2B . The guide finger  42  facilitates inserting the rod member  16  wrapped with a thickness T of the bag  20  through the gap  38  and into the interior space  30  of the clamp member  30 . 
     In an alternative embodiment as illustrated in  FIGS. 4A and 4B , the present sterilizeable, reusable flexible bag closure device  10  further comprises a pivotable linkage member  60  connecting a clamp open end  40  of a clamp member  12   a  to a rod member end  54  of the rod member  16   a . The linkage  60  allows the primary components of the device, the clamp member  12   a  and the rod member  16   a , to be kept together when not in use to close a bag opening, and thereby reduce the risk of losing one of the components of the device  10 . In  FIG. 4A , the linkage member  60  is an easily flexible thin section of the same material as the clamp member  12   a  and the rod member  16   a , and integrally molded to them. In  FIG. 4B , the linkage member  60   a  is a link-ring connecting the clamp member  12   b  and the rod member  16   b  as shown. 
       FIGS. 5A and 5B  are examples of alternative embodiments of the rod member  16  of the present bag closure device  10 . These figures illustrate other embodiments of the rod useful in practicing the present closure device  10 . A slot  56  can be included in the rod  16  through which the open end  22  may be passed to facilitate holding the open end  22  of the bag  20  closed while installing the closure device  10 . Also, as shown in  FIGS. 5A and 5C  the rod member  16   c  can be adapted to have a cutout  58  to facilitate folding or wrapping the open end  22  around the rod  16   c , for example when it is desired to have more than one thickness T of the open end  22  rolled around the rod  16   c  and received into the free space Df.  FIG. 5  illustrates an open slotted rod  16   d , which can be practiced in the present device  10  to facilitate inserting the open end  22  into the open slot  56   a  in the rod  16   d.    
     While the above description contains many specifics, these should not be construed as limitations on the scope of the invention, but rather as exemplifications of one or another preferred embodiment thereof. Many other variations are possible, which would be obvious to one skilled in the art. Accordingly, the scope of the invention should be determined by the scope of the appended claims and their equivalents, and not just by the embodiments.