Patent Publication Number: US-7905074-B1

Title: Apparatus and method for the automated manufacture of self-sealing inflatable dunnage bags

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This is a utility patent application taking priority from provisional application No. 61/174,544 filed on May 1, 2009. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to inflatable bags and more specifically to an apparatus and method for the automated manufacture of self-sealing inflatable dunnage bags, which greatly reduces the complexity of the inflatable bag. 
     2. Discussion of the Prior Art 
     It is well known in the art of inflatable dunnage bags to fill a bag structure with air and then heat seal the bag to retain the air therein. However, the dunnage bag is typically complicated or the machinery used to produce and fill the dunnage bag with air is also complicated. A complicated dunnage bag will require complicated machinery to fill thereof. A complicated dunnage bag inflation machine will not always produce a consistent product, due to the complexity of the machine and also variations in the sheet material used to produce the dunnage bag. 
     Typically, a manufacturer of inflatable dunnage bags provides a customer with bag filling machines at no cost and sells the inflatable dunnage bags to the customer. Any problems with the bag filling machine is the manufacturer&#39;s responsibility and expense. It is to the manufacturer&#39;s advantage to have the simplest and most inexpensive bag filling machines to produce the inflatable dunnage bags. Having inexpensive bag filling machinery makes it possible to sell the inflatable dunnage bags to smaller companies. 
     U.S. Pat. No. 5,351,828 to Becker et al. discloses an inflatable foil sachet, especially for packaging purposes. The Becker et al. patent includes a foil sachet with at least one chamber consisting of an upper and lower foil secured together by a closed seam. In order to fill the chambers with a substance, especially air, there is a channel having channel sections opening in the region of a seam and preferably in the region of the corner of the chamber concerned where there is an aperture in said chamber. 
     U.S. Pat. No. 5,447,235 to Pharo discloses a bag with squeeze valve and method for packaging an article therein. The Pharo patent includes an inflatable package adapted to be formed into a packaging system for retaining an article therein is formed with a pair of overlying inner panels defining a pocket therebetween adapted to retain an article therein an inflating portion for communicating through the overlying inner panels. 
     U.S. Pat. No. 7,444,795 to Yasuhira discloses a gas seal-in method for a bag with a gas filling compartment and packaging method for a bag with a gas filling compartment. The Yasuhira patent includes a method of sealing-in a gas in a gas filling compartment of a bag having a cut-in formed near the upper edge of the gas filling compartment. 
     Accordingly, there is a clearly felt need in the art for an apparatus and method for the automated manufacture of self-sealing inflatable dunnage bags, which provides a three layer inflatable dunnage bag that may be filled without the use of complicated bag filling machinery. 
     SUMMARY OF THE INVENTION 
     The present invention provides an apparatus and method for the automated manufacture of self-sealing inflatable dunnage bags, which greatly reduces the complexity of the bag filling machinery. The apparatus and method for the automated manufacture of self-sealing inflatable dunnage bags includes a bag making machine. The bag making machine includes a plurality of sheet roll spindles and a plurality of heat sealing rollers. A first bag sheet roll is retained on a first bag spindle. A second bag sheet roll is retained on a second bag spindle. A strip bag sheet roll is retained on a strip bag spindle. A first opening is formed through the first bag sheet for each bag. The first opening is formed adjacent one end of the bag. A second opening is formed through the strip bag sheet for each bag on the opposite end of the bag. The strip bag sheet has a much smaller width than the first and second bag sheet rolls. 
     Substantially each edge of the strip bag sheet is heat sealed to the first bag sheet with a strip heat sealing roller. The strip bag sheet is preferably heat sealed to a middle of the first bag sheet, but other locations could be used. A first bag heat sealing roller seals an end partition across a width of the first and second bag sheets. Substantially each edge of the first and second bag sheets are heat sealed to each other with a second bag heat sealing roller, such that the strip bag sheet is retained therebetween to form a plurality of inflatable bags. A perforation roller may be used to create a bag separation perforation in each end partition or a slitting knife may be used to separate the plurality of dunnage bags. The plurality of dunnage bags may be inflated using an air hose or any suitable bag filling machinery or device. 
     Accordingly, it is an object of the present invention to provide an apparatus and method for the automated manufacture of self-sealing inflatable dunnage bags, which provides a three layer dunnage bag that may be self-sealed without a complicated sealing operation. 
     Finally, it is another object of the present invention to provide an apparatus and method for the automated manufacture of self-sealing inflatable dunnage bags, which provides an inflatable dunnage bag that may be filled without the use of complicated bag filling machinery. 
     These and additional objects, advantages, features and benefits of the present invention will become apparent from the following specification. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of a bag making machine for the automated manufacture of self-sealing inflatable dunnage bags in accordance with the present invention. 
         FIG. 2  is a top view of a first bag sheet with a plurality of first openings formed on a bag making machine in accordance with the present invention. 
         FIG. 3  is a top view of a strip bag sheet with a plurality of second openings formed on a bag making machine in accordance with the present invention. 
         FIG. 4  is a top view of a strip bag sheet heat sealed to a first bag sheet on a bag making machine in accordance with the present invention. 
         FIG. 5  is a top view of a second bag sheet in accordance with the present invention. 
         FIG. 6  is a top view of a second bag sheet heat sealed to a first bag sheet to form a plurality of end partitions on a bag making machine in accordance with the present invention. 
         FIG. 7  is a top view of a second bag sheet heat sealed to a first bag sheet to form a plurality of dunnage bags on a bag making machine in accordance with the present invention. 
         FIG. 8  is an enlarged cross sectional view of a dunnage bag formed on a bag making machine in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference now to the drawings, and particularly to  FIG. 1 , there is shown a side view of a bag making machine  10 . The bag making machine  10  includes a plurality of sheet roll spindles and a plurality of heat sealing rollers. A first bag sheet  12  as a roll is retained on a first bag spindle  14 . A second bag sheet  16  as a roll is retained on a second bag spindle  18 . A strip bag sheet  20  as a roll is retained on a strip spindle  22 . The plurality of sheets are preferably fabricated from plastic sheeting. 
     With reference to  FIG. 2 , a first opening  24  is formed through the first bag sheet  12  for each bag. The first opening  24  is formed adjacent to one end of every bag. The first opening  24  is created with an automated punch  26  or the like. The first opening  24  could be a hole, a slit or any other suitable opening. A theoretical dashed division line  28  is shown to illustrate the length of each bag on the first bag sheet  12 . 
     With reference to  FIG. 3 , a second opening  30  is formed through the strip bag sheet  20  for each bag on the opposite end of every bag. The strip bag sheet  20  has a much smaller width than the first or second bag sheet rolls. The width of the strip bag sheet  20  is preferably less than one third of the width of the first bag sheet  12 . The second opening  30  is preferably created with an automated slitter  32  or the like. The second opening  30  could be a slit, a hole or any other suitable opening. 
     An optional sealant application device  34  may be used to ensure a seal between the first bag sheet  12  and the strip bag sheet  20 . The sealant application device  34  would preferably apply a sealant substance  36  to an underside of the strip bag sheet  20  between the first opening  24  and the second opening  30 , but could be applied to the first bag sheet  12 . The sealant substance  36  could also be applied around a perimeter of the first or second openings. The sealant substance  36  seals the first bag sheet  12  to the strip bag sheet  20  to prevent air from leaking out of the first opening  24 . The sealant substance  36  is preferably a substance or liquid with removable adhesive, tacky or sticky properties. Substances or liquids with the removable adhesive, tacky or sticky properties include vasoline, oil, water, liquid soap, soapy water or any other suitable substance. 
     With reference to  FIG. 4 , substantially each edge of the strip bag sheet  20  is heat sealed to the first bag sheet  12  with a strip heat sealing roller  38  to form a pair of substantial strip edge seals  35 . With reference to  FIG. 8 , an air channel  37  is formed between the pair of substantial strip edge seals  35 . The strip bag sheet  20  is preferably heat sealed to a middle of the first bag sheet  12 , but other locations could also be used. With reference to  FIG. 5 , the second bag sheet  16  includes the plurality of theoretical dashed division line  28  to illustrate the length of each bag on the second bag sheet  16 . 
     With reference to  FIG. 6 , a first bag heat sealing roller  40  seals an end partition  42  across a width of the first and second bag sheets. With reference to  FIG. 7 , substantially each edge of the first and second bag sheets are heat sealed to each other with a second bag heat sealing roller  44  to form a pair of substantial edge seals  46 , such that the strip bag sheet  20  is retained therebetween to form a plurality of inflatable bags  11 . A bag cavity  50  is formed inside the two end partitions  42  and the pair of substantial edge seals  46 . A perforation roller (not shown) may be used to create a bag separation perforation in each end partition  42  or a slitting knife  48  may be used to separate the plurality of inflatable bags  11 . 
     Heat sealing rollers  38 ,  40 ,  44  have been disclosed as the method for sealing strip bag sheet  20  to the first bag sheet  12  and the first bag sheet  12  to the second bag sheet  20 . However, the manufacture of the inflatable bags  11  should not be limited to assembly by heat sealing alone, but should include sealing through glue, adhesive, cement or any other suitable sealing method. Sealing with glue, adhesive or cement would include applying a strip of glue, adhesive or cement to at least one sheet to be sealed and pressing the two sheets together to form the seal. The application of the glue, adhesive or cement would be applied with any suitable manufacturer method or process. The glue, adhesive or cement includes ultra-violet cured glue, adhesive and cement. 
     With reference to  FIG. 8 , the plurality of inflatable bags  11  are inflated by blowing air into the first air opening  24 . The air introduced through the first air opening  24  flows through the air channel  37  to the second air opening  30  and into the bag cavity  50  formed between the first and second bag sheets. Air pressure forces the strip bag sheet  20  downward against the first bag sheet  12  to form a contact seal. The optional use of the sealant  36  insures that the seal is formed for inflatable bags  11  having a shorter length. The plurality of inflatable bags  11  may be inflated through an air hose or any suitable automatic inflation device. 
     While particular embodiments of the invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.