Patent Application
20070223844
This invention relates to flexible containers, including but not limited to flexible containers formed from a sheet of material.
Flexible bags made of paper are known. These paper bags are usually disposable bags that are used to carry various articles, including groceries. A typical paper bag is formed by attaching two opposite ends of a piece of paper to form a tube, and then folding one end in to form a cavity within the tube that is open on one end and closed on a folded end.
Paper bags are widely used because of their low cost of manufacture. Nevertheless, one disadvantage is their low strength. The strength of a paper bag is limited by either the strength and resistance to tears of the paper material, or by the strength of the attachment seams that form both a lengthwise seam of the tube, and all the seams used to attach the various folds and flaps that form the folded end. An additional disadvantage is the relative complexity of creating folded end in a mass production environment. Each of the folds on one end of a known paper bag may require a dedicated device to create and secure them, thus making their manufacture a time consuming process.
Accordingly, there is a need for a relatively inexpensive bag that has higher strength than a known paper bag, and is also easier to manufacture.
A flexible container that is suited for a mass production process, and that is stronger than the known flexible containers, is disclosed herein. The flexible container of one embodiment has an internal volume and an opening, and includes a first front panel, a second front panel, and a bottom panel that is located between the first front panel and the second front panel. The container further includes two side panels, each side panel including a first flap connected to the first front panel, a second flap connected to the second front panel, and a third flap connected to the bottom panel. A continuous sheet of material has a first fold and a second fold. The first fold separates a first front panel and the bottom panel, and the second fold separates the bottom panel from the second front panel. At least one seam connects each first flap and each second flap, and each third flap is connected to at least one of the corresponding first flap and second flap.
The following describes an apparatus for and method of manufacturing and using a flexible container that is relatively inexpensive and has a higher strength than known flexible containers. A flexible container 100 is shown in
The first and second broad panels 106 and 108, along with the bottom panel 114, are advantageously connected to each other and are formed by an uninterrupted section of material or sheet. When the flexible container 100 contains a working load, for example articles that may be placed into the container for conveyance, the container 100 may effectively contain the working load and carry the working load with the first and second broad panels 106 and 108, and the bottom panel 114. The uninterrupted section of material making up these panels may advantageously give the container 100 superior strength.
The container 100 may be assembled or constructed from a sheet of material 200. The sheet 200 is shown in
The sheet 200, when unfolded, includes a plurality of four incisions 202. The incisions 202 are located in symmetrical locations to each other on the sheet 200. The sheet 200 has a length, L, and a width, W. The length L of the sheet 200 may be divided into a first segment 204, a second segment 206, and a third segment 208, on either side of the sheet 200. The width W may be an uninterrupted segment on opposing edges of the sheet 200, with no incisions. A plurality of folds or creases may be formed in the sheet 200 during and/or after assembly of the sheet 200 into the container 100. A first, second, and third longitudinal creases 210, 212, and 214 may span the length L of the sheet 200, running substantially parallel to the segments 204, 206, and 208. A first and a second latitudinal creases 216 and 218 may connect two incisions 202 each, be aligned with the incisions 202, and span the width W of the sheet 200 that remains between the incisions 202. A first, second, and third segment 220, 222, and 224 may be formed on either edge of the sheet 200 spanning the width W.
The sheet 200 may advantageously be segmented into nine panels that are defined between the incisions 202 and/or the creases 208, 210, 212, 214, 216, and 218. A first front panel 226 may be defined between the segment 222, the creases 210, and the crease 216. Similarly, a second front panel 228 may be defined between the segment 222 on an opposing edge of the sheet 200, the creases 214, and the crease 218. A bottom panel 230 may be defined by the creases 212, 216, and 218, and be located between the panels 226 and 228 along the length L of the sheet 200. Two first side panels 232 may be adjacent to the first front panel 226, one on either side thereof, and defined by the segments 220 and 224, the creases 210, and the incisions 202. Similarly, two second side panels 234 may be adjacent to the second front panel 228, one on either side thereof, and defined by the segments 220 and 224, the creases 214, and the incisions 202. Two third side panels 236 may be defined by the incisions 202, the creases 212, and the segments 206, and be located adjacent to the bottom panel 230, one on either side thereof, and between the side panels 232 and 234 along the length L of the sheet 200.
A method of assembling the container 100 from the sheet 200 is shown in
When the shaping operation of the sheet 200 has been completed, a bonding operation may be performed to connect some panels to each other and form the container 100. Panels may be connected to each other in various fashions, which fashions may depend on the type of material used for the sheet 200. Attachment methods that may be used include stitching, gluing, riveting, thermally or vibrationally welding, and so forth. In a preferred embodiment the material used for the sheet 200 may be Tyvek® Type 10 or other types, manufactured by the DuPont Corporation. Adhesives compatible with this material are known in the industry, and any suitable material may be used to adhere panels formed from a sheet of Tyvek® to each other. In a preferred embodiment, the panels of the container 100 are bonded using natural product adhesives based on starch, dextrin, casein, or animal by-products, which are preferred over synthetic-based adhesives. Some polyurethane adhesives provide optimum adhesion (lap and shear), flexibility and water resistance.
A bonding configuration for the container 100 is shown in
A design for the container 100 is advantageously well suited for a mass production operation. A plurality of preconfigured sheets 800 may be part of a roll of material 801, as shown in
When in the machine 900, the sheet 800 may undergo folding operations that are accomplished by retention and deformation or folding of panels by a plurality of carriages 902 attached to the machine 900. The machine 900 may have a feeding and portioning device 904 that straightens and portions each sheet 800 before each sheet enters the carriages 902. Referring to
The flexible container 100 is advantageous when compared with flexible containers that are currently available, because it is able to withstand conveyance of heavier loads for a same material and thickness used to make the container as compared to a known flexible container of a similar size. The container described herein may be capable of an increased load carrying capacity of up to 80% when compared to a typical container. Moreover, a container in accordance with the invention is well suited for mass production because there are limited cuts and removal of material from a forming sheet. Many known designs for flexible containers entail creation of a tube shape out of a sheet of material, followed by various cutting and folding operations to form the tube into a cylinder, and finally fold one end of the cylinder to form a container. These operations are both time consuming and present challenges for a fast paced manufacturing operation. In contrast, a container as described herein may be formed out of a sheet of material allowing use of a roll, there is no removal of material from the sheet required, a number of incisions may be pre-cut into the sheet or may be cut into a forming machine, and there are merely 4 folding operations, 2 panels each, that need to be completed to form the container. These features enable a cost and time effective production operation to be employed.
A flowchart for a method of producing a flexible container is shown in
The machine may be used to fold the main sheet once to form a first side panel, and once more to form a second side panel and a bottom panel at step 1006. These panels may enclose an interior volume on three sides. Each of the four large flaps and the two small flaps may be folded around the interior volume at step 1008. Two of each of the large flaps and one of each of the two flaps are may be located adjacent to each other. The two of each of the large flaps and the one of each of the two flaps are connected together to form the flexible container at step 1010. The flexible container now enclosed five sides of the interior volume. The flexible container may be ejected from the machine at step 1012.
A flowchart for a method for making a flexible container is shown in
The flexible container disclosed herein is well suited as a conveyance for manual transportation for articles, but may also advantageously be used as a toy platform for small animals, for example, felines. A container constructed in accordance with the invention is more resilient and robust, and better suited to withstand use as a toy by an animal. Various add-on toys may be used in conjunction with the flexible container described herein. For example, a toy article may be connected to a distal end of a string. The string may be attached through, for example, a hole formed in one of the panels of the container, to allow a feline to play with the toy article both inside the interior volume of the container, as well as outside the opening.
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.
