AU2009101022A4 - Easy Fill Gusseted Sack - Google Patents

Description

tasy in uussetea baCK ref. no. 2008905401 AUSTRALIA Patents Act 1990 SPECIFICATION Innovation Patent Easy Fill Gusseted Sack 6 October 2009 The invention is described in the following statement Page 1 tasy i1i Lussetea baCK ref. no. 2008905401 This invention involves the manufacture of a bag or sack for use in packaging powders and granules such as wheat flour (flour). It can be applicable to a bag or sack (sack) of any size but more commonly applicable to a sack for packaging 25 kg of flour. The invention also 5 involves the adaption of the packaging system machinery that is used to automatically fill the sack with powder or granules and it involves the way in which the sack and the packaging system, in combination, provide a final package that is suitable for use by the final customer of the packaged product. .o Typically these sacks will be made of kraft paper but may be made of other common packaging materials such as woven polypropylene or polyethylene. Typically these sacks will be packed on fully automated filling systems and an important element of this invention is to ensure that this can be done. However, the invention can be applied .s to semi automatic and manual filling operations with the same benefits resulting An existing and preferred method of packaging flour is to use an open mouth sack that has gusseted side folds, to enable the filled sack to form into a block shape for distribution (refer to Figure 1). An 20 alternate method is to use an open mouth sack that is flat and has no gusseted side folds. This alternate sack is easier for sack makers to manufacture by current methods but provides an inferior shape when filled with flour. The filled sack shape of this alternate sack (refer to Figure 2) is more of a wedge shape when compared to the 25 block shape of the gusseted sack. Many of the filling systems currently installed in Australia, to package Flour, have been designed to use flat sacks rather than gusseted sacks. These filling systems provide for higher efficiency in the filling Page 2 tasy i1i Lussetea baCK ref. no. 2008905401 process but create filled package shapes that are less than optimal for palletisation and distribution. Automated filling systems have been developed to process sacks with gusseted side folds and these systems can be utilised to 5 optimise both the packing system and the distribution system. However, the capital cost of changing from a filling system that is designed for flat sacks to a filling system designed for gusseted sacks, is substantial. The investment required for the smaller scale Flour Mills that operate within the Australian economy is generally .o considered to be too great. The purpose of this invention is to create a method of achieving a block shaped filled sack using a gusseted open mouth empty sack and an existing filling line that is otherwise designed to use flat sacks. This will avoid the need significant capital investment that would .s normally be required. This invention modifies a gusseted sack by selectively applying adhesive to parts of the side folds at the top of the sack. The internal and external surfaces of the sack will have adhesive added in a line adjacent to its top edge. This modification will create the effect of 20 the sack appearing to be flat for the purposes of the filling system. These modified sacks can then be processed on existing filling systems that prefer 'flat sacks'. (Refer to Figure 3 and Figure 4.) A consequence of selectively applying adhesive to the inner and outer walls of the top of the sack is that this reduces the size of the 25 opening at the top of the sack where this adhesive is applied. This change to the top of the sack can make it difficult to remove product from the filled sack and the package would be considered to be unsuitable for use by the final customer. Page 3 tasy i1i Lussetea baCK ref. no. 2008905401 An element in this invention is that these adhered areas at the top of the sack are removed by a trimming process in the sack closing stage. This procedure will result in the top opening of the filled sack being released to be "full size" and making the top opening usable as if it 5 were a conventional gusseted sack. The development of the concept described in this patent will require the creation of a process, and apparatus, to selectively place adhesive at the top of the sack during sack making. It will also require careful determination of the inter-relationships between the .o location of the adhesive applications, the physical dimensions of the existing sack handling apparatus on the filling machine and the operation of the top trimming device on the sack closing machine. The expected benefits of this invention are that the new sack design will enable the Australian Flour Industry to change the packaging of .s their flour into block shaped gusseted sacks without needing to spend substantial capital to reconfigure their packing lines. Page 4

Claims (5)

1. This invention involves manufacturing the open top end of a bag or sack (sack) so that it is formed to appear like a flat, non gusseted sack, even though the body of the sack has 5 been primarily formed with gusseted side folds, and where the sack is manufactured with one, two or more layers of materials to form the wall of the sack, and where the materials used in manufacturing the sack may include paper, sack kraft, polymer, woven fabric or the like, as required by .0 the purchaser of the empty sack.

2. This invention involves selective placement of adhesive on the inner surfaces of the sack and the outer surfaces of the sack, in an area adjacent to the top opening of the sack, to .s create the effect of the top opening of the sack having no gusset folds and to provided a top opening of the sack or sack that is effectively flat in appearance. This is achieved by the adhesive forming a permanent bond between the kraft, or other bag materials selected to form the wall of the sack, 20 surfaces of the sack wall that are in contact with the adhesive. The selective placement of the adhesive on the inner surfaces of the sack and the outer surfaces of the sack, in an area adjacent to the top opening of the sack will provide for 25 the convenient removal of the top portions of the sack, that have been bonded together by the selectively placed adhesive, in a process of trimming away the top edge of the open bag during the bag closure procedure. Page 9 tasy i1i Lussetea baCK ref. no. 2008905401

3. This invention involves adapting the sack filling process, such that during the filling and closing process, the selectively glued area adjacent to the top opening of the sack can be removed from the sack by cutting or trimming away the top 5 section of the sack to ensure that all areas of the sack, that had been selectively adhered together, are no longer bonded. This invention involves the selective removal of a portion of the top of a filled sack, after filling and during the closure of .0 the filled sack, to make the side gusseted folds at the top of the sack unattached from one another and free to unfold to create a full opening at the top of the sack when the filled sack is opened by the final customer. .s

4. This invention includes the creation of an empty unfilled sack which has a flat non gusseted top opening prior to being filled and closed and will have a gusseted top opening after the sack is opened. This invention involves the creation of a process and 20 apparatus to selectively place adhesive on the inner and outer surfaces of the sack to ensure these surfaces are adhered together in an area adjacent to the top opening of the sack. This invention involves the creation of a process and 25 apparatus to selectively place adhesive on the inner and outer surfaces of the sack to ensure these surfaces are adhered together in an area adjacent to the top opening of the sack, where the process could be performed cooperatively with an automated sack making process or Page 10 tasy i1i Lussetea baCK ref. no. 2008905401 independently after the completion of the sack manufacture.

5. This invention provides person who fills the sack (The Filler) 5 with a package that that provides maximum access to the contents of the sack when opened by their customer and made ready to use the flour. The Filler can provide this package to their customer by using a gusseted sack on a filling system designed for flat sacks without. o0 This invention can be used with existing sack closing procedures such as; stitching, folding, taping or pinch losing. In a preferred application of this invention, a portion of the sack adjacent to the top opening is removed by cutting (or trimming) prior to the sack being closed by stitching, folding or taping. Page 11