VACUUM PACKAGING BAGS WITH GUSSETS AND METHODS FOR USING AND MANUFACTURING VACUUM PACKAGING BAGS WITH GUSSETS
TECHNICAL FIELD
The present invention generally relates to vacuum packaging. More particularly, the invention is directed to vacuum packaging bags with gussets and methods for using and manufacturing vacuum packaging bags with gussets.
BACKGROUND
Vacuum packaging involves removing air or other gases from a storage container and then sealing the container to prevent the contents from being exposed to ambient air. Vacuum packaging is particularly useful in protecting food and other perishables against oxidation.
Oxygen is a main cause of food spoilage and contributes to the growth of bacteria, mold, and yeast. Accordingly, vacuum-packaged food often lasts three to five times longer than food stored in ordinary containers. Moreover, vacuum packaging is useful for storing clothes, photographs, silver, and other items to prevent discoloration, corrosion, rust, and tarnishing. Vacuum packaging also produces tight, strong, and compact packages, reducing the bulk of articles and allowing for more space to store other supplies.
Figures IA and IB are schematic isometric views of a conventional appliance 10 for vacuum packaging an object 98 (shown in broken lines) in accordance with the prior art. The vacuum packaging appliance 10 includes a base 20, a lid 40 pivotably coupled to the base 20, a lower trough 22 in the base 20, an upper trough (not shown) in the lid 40, and a vacuum pump
(not shown) operably coupled to the upper trough. The lid 40 pivots between an open position (shown in Figure IB), in which a portion of a bag 60 can be placed between the lid 40 and the base 20, and a closed position (shown in Figure IA), in which the bag 60 can be evacuated and thermally sealed. In the closed position, the upper trough and the lower trough 22 are aligned and form a vacuum chamber to remove gas from the interior of the bag 60. The base 20 includes a seal 24 surrounding the vacuum chamber to seal the chamber from ambient air while gas is removed from the interior of the bag 60. The vacuum packaging appliance 10 further includes a heating element 35 to thermally seal the bag 60 after the gas has been evacuated.
Conventional vacuum packaging bags include two panels attached together with an open end. Typically, the panels each include two or more layers. The inner layer can be a heat sealable material, and the outer layer can be a gas impermeable material to provide a barrier against the influx of air. The plasticity temperature of the inner layer is lower than the outer layer. As such, the bag can be heated to thermally bond the inner layer of each panel together to seal the bag without melting or puncturing the outer layer.
A conventional vacuum packaging process includes depositing the object 98 into the bag 60 and positioning an open end 62 of the bag 60 in the lower trough 22 of the vacuum packaging appliance 10. Next, the lid 40 pivots downward to form the vacuum chamber with the open end 62 of the bag 60 disposed within the vacuum chamber. The vacuum pump then removes gas from the vacuum chamber and the interior of the bag 60, which is in fluid communication with the vacuum chamber. After gas has been removed from the interior of the bag 60, the heating element 30 heats a strip of the bag 60 proximate to the open end 62 to bond the inner layer of each panel together and thermally seal the bag 60. One problem with conventional vacuum packaging bags is that bags configured to store bulky objects have big panels, which require a large vacuum packaging appliance to evacuate and seal. Large appliances have relatively big footprints and consume significant space on a countertop or other surface. For example, the footprint of the appliance 10 illustrated in Figures IA- IB is the surface area of the bottom of the base 20. Accordingly, there is a need to provide vacuum packaging appliances with smaller footprints.
BRIEF DESCRIPTION OF THE DRAWINGS
Figures IA and IB are schematic isometric views of a conventional appliance for vacuum packaging objects in accordance with the prior art.
Figure 2 is a schematic isometric view of a vacuum packaging system including a vacuum packaging appliance and a vacuum packaging bag in accordance with one embodiment of the invention.
Figure 3 is a schematic front isometric view of the vacuum packaging bag of Figure 2.
Figure 4 is an enlarged schematic cross-sectional side view of a portion of the vacuum packaging bag of Figure 2 with the first and second panels pressed together. Figure 5 is a schematic front isometric view of a vacuum packaging bag in accordance with another embodiment of the invention.
Figure 6 is a schematic front isometric view of a vacuum packaging bag in accordance with another embodiment of the invention.
Figure 7 is a schematic front isometric view of a bag roll for forming vacuum packaging bags in accordance with another embodiment of the invention.
Figure 8 is a flow chart illustrating a method of using vacuum bags according to one aspect of the invention.
DETAILED DESCRIPTION
A. Overview The present invention is directed toward vacuum packaging bags and methods of manufacturing and using vacuum packaging bags. In one embodiment, a vacuum packaging bag includes a first panel, a second panel coupled to the first panel, and a gusset between the first and second panels. The first panel has a first gas impermeable layer and a first sealable layer coupled to the first gas impermeable layer. The second panel has a second gas impermeable layer and a second sealable layer coupled to the second gas impermeable layer. The gusset can extend along a length of the bag and project inwardly toward an interior region.
In another embodiment, a vacuum packaging bag includes a first panel and a second panel coupled to the first panel. The first panel has a plurality of intercommunicating channels, a first edge, a second edge opposite the first edge, a first gas impermeable layer, and a first sealable layer
coupled to the first gas impermeable layer. The second panel has a third edge, a fourth edge opposite the third edge, a second gas impermeable layer, and a second sealable layer coupled to the second gas impermeable layer. The bag further includes a first gusset between the first and third edges and a second gusset between the second and fourth edges. In one aspect of this embodiment, the sealable layers are formed of a material such that the first sealable layer pealably bonds with the second sealable layer under the influence of heat and/or pressure. The sealable layers may also be formed of a material such that the first sealable layer permanently bonds with the second sealable layer.
The following disclosure describes several embodiments of vacuum packaging bags and methods of manufacturing and using vacuum packaging bags. Several details describing structures and processes that are well known and often associated with vacuum packaging appliances and bags are not set forth in the following description for purposes of brevity. Moreover, although the following disclosure sets forth several embodiments of different aspects of the invention, several other embodiments of the invention can have different configurations or different components than those described in this section. As such, it should be understood that the invention may have other embodiments with additional elements or without several of the elements described below with reference to Figures 2-8.
B. Embodiments of Vacuum Packaging Systems Including Vacuum Packaging Bags and Vacuum Packaging Appliances Figure 2 is a schematic isometric view of a vacuum packaging system 100 including a vacuum packaging appliance 110 and a vacuum packaging bag 160 in accordance with one embodiment of the invention. The vacuum packaging appliance 110 includes a base 120, a lid 140, and a hinge 150 pivotably coupling the lid 140 to the base 120. The lid 140 is pivotable about an axis A-A between an open position (shown in Figure 2) and a closed position. The illustrated base 120 includes a first chamber portion 122 and a first seal 124 surrounding the first chamber portion 122. The lid 140 can include a second chamber portion 142 and a second seal 144 surrounding the second chamber portion 142. When the lid 140 is in the closed position, the first and second chamber portions 122 and 142 form a vacuum chamber. In other embodiments, the vacuum packaging appliance 110 can have other configurations. For example, the base 120 and/or the lid 140 might not include a chamber portion and/or a seal. Moreover, the vacuum packaging appliance 110 may be lidless.
The vacuum packaging appliance 110 further includes a vacuum pump 130 (shown in broken lines) operably coupled to the first and/or second chamber portion 122 or 142 for removing gas from the vacuum chamber when the lid 140 is in the closed position. The vacuum pump 130 can also remove gas from the interior of the bag 160 when an open end 162 of the bag 160 is positioned in the vacuum chamber. The bag 160 is configured so that the interior of the bag 160 is in fluid communication with the vacuum chamber when the lid 140 is in the closed position, as described in greater detail below with reference to Figure 4. Accordingly, the vacuum pump 130 can remove gas from the vacuum chamber and the interior of the bag 160.
In the illustrated embodiment, the vacuum packaging appliance 110 further includes a heating element 135 and a member 155 for pressing the bag 160 against the heating element 135.
The heating element 135 can be carried by the base 120, and the member 155 can be carried by and project from the lid 140. The heating element 135 is configured to thermally seal the bag 160 after the gas has been substantially evacuated from the interior of the bag 160. The heating element 135 heats the bag 160 and the member 155 presses the bag 160 against the heating element 135 to ensure a seal is formed across the bag 160. In other embodiments, the vacuum packaging appliance 110 can have a different configuration.
C. Embodiments of Vacuum Packaging Bags Having Gussets
Figure 3 is a schematic front isometric view of the vacuum packaging bag 160 of Figure 2. The bag 160 includes a first panel 164 and a second panel 174 coupled to the first panel 164. The first panel 164 can include a first edge 168a, a second edge 168b, a third edge 168c opposite the first edge 168a, and a fourth edge 168d opposite the second edge 168b. The second panel 174 can include a first edge 178a, a second edge 178b, a third edge 178c opposite the first edge 178a, and a fourth edge 178d opposite the second edge 178b. In the illustrated embodiment, the second edge 168b and the third edge 168c of the first panel 164 are attached to the second edge 178b and the third edge 178c, respectively, of the second panel 174. The fourth edges 168d and 178d of the first and second panels 164 and 174 are unconnected and define the open end 162 of the bag 160. The first and second panels 164 and 174 define an interior region 184 into which an object(s) can be placed.
The illustrated vacuum packaging bag 160 further includes a gusset 190 between the first and second panels 164 and 174. The gusset 190 has a first portion 191a attached to the first panel 164 at the first edge 168a and a second portion 191b attached to the second panel 174 at
the first edge 178a. The illustrated gusset 190 extends along a length L of the bag 160 and projects inwardly toward the interior region 184 when the bag is empty. In other embodiments, such as the embodiments described below with reference to Figures 5-6, the bag may include a different number of gussets and/or the gusset may extend along a width of the bag. One advantage of the illustrated bag 160 is that the gusset 190 increases the storage capacity of the bag 160. The storage capacity is increased because the gusset 190 allows the first and second panels 164 and 174 to move a greater distance apart from each other. More specifically, as objects are placed into the interior region 184, an angle α between the first and second portions 191a-b increases and the gusset 190 moves in a direction Di so that the first and second panels 164 and 174 can move away from each other. As such, the bag 160 can carry a greater volume of objects. Although the storage capacity of conventional bags can be increased by increasing the size of the panels, the larger panels require a bigger vacuum packaging appliance to evacuate and seal the bag. Bigger vacuum packaging appliances have larger footprints and require more space on the countertop or other surface. The gusset 190 in the illustrated bag 160, however, increases the storage capacity of the bag 160 without increasing the size of the panels.
Consequently, the bag 160 can be evacuated and sealed by an appliance with a smaller footprint.
Another feature of the illustrated bag 160 is that as an object is placed into the bag 160 and the first and second panels 164 and 174 move apart, the first and second panels 164 and 174 remain generally flat and, consequently, the footprint of the first and second panels 164 and 174 does not change significantly. An advantage of this feature is that the generally flat panels are easier to seal together in a vacuum packaging appliance. In contrast, when an object is placed in a conventional bag that does not have a gusset, the panels curve to increase the interior volume of the bag and, consequently, the footprint of the panels is reduced. The open end of these conventional bags is more difficult to seal. Figure 4 is an enlarged schematic cross-sectional side view of a portion of the vacuum packaging bag 160 with the first and second panels 164 and 174 pressed together. The first and second panels 164 and 174 each include a gas impermeable layer 180 (identified individually as 180a-b) and a sealable layer 182 (identified individually as 182a-b) coupled to the corresponding gas impermeable layer 180. The gas impermeable layers 180a-b provide a barrier against the influx of air. The sealable layers 182a-b can have a different temperature of plasticity than the gas impermeable layers 180a-b so that the bag 160 can be heated to bond the sealable layers 182a-b
together without melting or puncturing the gas impermeable layers 180a-b. In other embodiments, the first and second panels 164 and 174 can further include an additional layer(s), such as a structural layer, to increase the strength and rigidity of the bag 160.
The sealable layers 182 can include a pealably sealable layer and/or a substantially permanently sealable layer. The pealably sealable layer includes resin or other materials that through pressure, heat, or another sealing enabler, form a pealable seal that is opened through a manual pealing action. The manual pealing action does not require a tool and does not result in wasting or destroying a portion of the vacuum packaging bag. Permanently sealable layers can include resin that with heat forms a generally permanent seal. In several embodiments, the sealable layers 182 can include a material which when heated to a first temperature forms a pealable seal and when heated to a second temperature forms a permanent seal.
In the illustrated embodiment, the second panel 174 includes a plurality of intercommunicating channels 175 configured to exhaust gas from the interior of the bag 160 when the first and second panels 164 and 174 are pressed together as shown in Figure 4. Accordingly, when the lid 140 (Figure 2) of the vacuum packaging appliance 110 (Figure 2) is in the closed position and the bag 160 is sandwiched between the first and second seals 124 and 144 (Figure 2), gas can be evacuated from the interior region 184 (Figure 3) of the bag 160 through the channels 175. In other embodiments, the second panel 174 may not include the channels 175.
Figure 5 is a schematic front isometric view of a vacuum packaging bag 260 in accordance with another embodiment of the invention. The bag 260 illustrated in Figure 5 is generally similar to the bag 160 described above with reference to Figure 3. For example, the illustrated bag 260 includes a first panel 164, a second panel 274 coupled to the first panel 164, and a first gusset 190 between the first and second panels 164 and 274. The illustrated bag 260, however, does not include a plurality of intercommunicating channels in the second panel 274. Moreover, the illustrated bag 260 includes a second gusset 293 between the first and second panels 164 and 274 and opposite the first gusset 190. The second gusset 293 includes a first portion 294a attached to the first panel 164 at the third edge 168c and a second portion 294b attached to the second panel 274 at the third edge 178c. The first and second gussets 190 and 293 accordingly increase the storage capacity of the bag 260. In other embodiments, the first and/or second panel 164 and/or 274 of the bag 260 may include a plurality of intercommunicating channels to facilitate the evacuation of gas from the bag 260.
Figure 6 is a schematic front isometric view of a vacuum packaging bag 360 in accordance with another embodiment of the invention. The bag 360 illustrated in Figure 6 is generally similar to the bag 260 described above with reference to Figure 5. For example, the illustrated bag 360 includes a first panel 164, a second panel 274, a first gusset 190, and a second gusset 293. The illustrated bag 260, however, further includes a third gusset 396 between the first and second panels 164 and 274. The third gusset 396 includes a first portion 297a attached to the first panel 164 at the second edge 168b and a second portion 297b attached to the second panel 274 at the second edge 178b. The first, second, and third gussets 190, 293, and 369 accordingly increase the storage capacity of the bag 360. Figure 7 is a schematic front isometric view of a bag roll 461 for forming vacuum packaging bags in accordance with another embodiment of the invention. The illustrated bag roll 461 includes a first sheet 466, a second sheet 476 coupled to the first sheet 466, and an open end 462. The first sheet 466 includes a first edge 468a and a second edge 468c opposite the first edge 468a, and the second sheet 476 includes a first edge 478a and a second edge 478c opposite the first edge 478a. The first and second sheets 466 and 476 can include gas impermeable layers and sealable layers, similar to those described above with reference to Figure 4. The bag roll 461 further includes (a) a first gusset 490 between the first edge 468 a of the first sheet 466 and the first edge 478a of the second sheet 476, and (b) a second gusset 493 between the second edge 468c of the first sheet 466 and the second edge 478c of the second sheet 476. Bags are formed from the bag roll 461 by pulling out a portion of the first and second sheets 466 and 476, cutting the sheets 466 and 476, for example, along line B-B, and sealing one of the open ends.
Figure 8 is a flow chart illustrating a method 500 according to one aspect of the invention. The method 500 begins at step 502 wherein a user cuts a portion of a bag roll, such as described above with reference to Figure 7. In step 504, the user seals one of the two open ends of the portion of the bag roll. The step 504 may involve applying heat, pressure, or both, in a predefined range and for a predefined time period. For example, the end can be pealably or permanently sealed with the heating element 135 ofthe vacuum packaging appliance 110. If a user is using a preformed bag, however, the steps 502 and 504 are unnecessary. In step 506, the user places an object into the bag. In step 508, the user evacuates the bag. Evacuation typically involves placing the open end ofthe bag in the vacuum chamber of an appliance and closing the lid ofthe appliance. In step 510, the open end ofthe bag is sealed. The seal can be a pealable or
permanent seal as described above with reference to the step 504. In step 512, the user stores the object in the sealed bag as desired.
As the side-gusseted portion of the bag has additional bag material, sealing tends to require more energy than bags not having the extra thickness of the side-gussets. This is not a difficult problem to compensate for, simply meaning that more energy must be used and perhaps users should be aware of this requirement to ensure that seals are properly made. Additionally, the side-gusseted bag may best be made from PE or PP materials as these seal more readily than competing nylon materials. However, any suitable material may be used as long as the proper care is taken. From the foregoing, it will be appreciated that specific embodiments of the invention have been described herein for purposes of illustration, but that various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.