EVACUABLE STORAGE BAG

Abstract

A plastic storage bag which has flexible thermoplastic sidewalls can be evacuated by a vacuum device to preserve food items. The bag includes an interior volume provided by the sidewalls in which the food items can be inserted through an open top edge. Air from interior volume can also be withdrawn through the open top edge by the vacuum device prior to sealing the opening. To prevent the sidewalls from collapsing against themselves in a manner that impedes the flow of air to the vacuum device, the bag can include a separation member that maintains some separation between the sidewalls proximate the open top edge.

Description

BACKGROUND

Flexible thermoplastic storage bags are used in a wide variety of applications including the storage of food items, either temporarily in the case of packaging snacks or long term in the case of freezer storage. Plastic bags of this type typically include one or more pliable, thermoplastic sidewalls configured to provide an interior volume to receive the food items. The interior volume is accessible via an opening disposed through the sidewall. To seal closed the opening, the bag may be subjected to a heat sealing operation wherein the material proximate the opening is melted together. In other embodiments, the plastic bag can include interlocking fastening strips that may releasably engage with each other to close the opening.

One common problem that occurs with such storage bags is that after the opening has been sealed, latent air can remain trapped in the interior volume. Besides undesirably increasing the overall size of the sealed bag, the trapped air can cause spoliation or, in the case of freezer storage, freezer burn of food items stored in the interior volume.

BRIEF SUMMARY

The bag may include at least one thermoplastic sidewall configured to provide an interior or internal volume that is accessible via an opening disposed through the sidewall. To prevent the sidewall from collapsing against itself or against stored food items during evacuation, the storage bag may include a separator member located in close proximity to the opening. The separator member may maintain separation of the sidewall during evacuation so as to facilitate withdrawal of air.

The thermoplastic material of the bag may include a thermoplastic material that can be subjected to a heat sealing operation for melting closed the opening after evacuation of the interior volume. In other embodiments, the bag may include first and second fastening strips for releasably closing the opening. A system and method can be used which uses a vacuum device and a plastic bag including a separator member proximate an opening for maintaining separation of the sidewalls during evacuation.

An advantage is that the separator member facilitates withdraw of air from the interior volume of a vacuum storage bag. A related advantage is that the plastic bag and corresponding system can better preserve food items for later consumption. These and related advantages and features will become apparent from the following drawings and detailed description of the embodiments.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a perspective view of a flexible plastic storage bag in relation to a vacuum device, the storage bag may include a separation member in the form of a piece of compressible foam proximate the opening.

FIG. 2 is a cross-sectional view of the flexible plastic storage bag inserted into the vacuum device of FIG. 1.

FIG. 3 is a detailed view of the area A-A indicated in FIG. 2 illustrating the plastic storage bag with the separation member inserted into the vacuum device.

FIG. 4 is a detailed view similar to that of FIG. 3 showing another embodiment of the plastic storage bag including a separation member in the form of a first and a second piece of compressible foam proximate the opening.

FIG. 5 is a perspective view of another embodiment of a plastic storage bag having a separator member in the form of a semi-rigid tube.

FIG. 6 is a top plan view of the embodiment of the plastic storage bag of FIG. 5 showing the semi-rigid tube attached to a sidewall.

FIG. 7 is a top plan view of another embodiment of a plastic storage bag having a separator member in the form of a corrugated area formed proximate the opening.

FIG. 8 is a top plan view of another embodiment of a plastic storage bag having a separator member in the form of first and second substantially rigid arch portions formed in the bag material.

FIG. 9 is a cross-sectional detailed view similar to that of FIG. 3 showing the plastic storage bag of FIG. 8 with the first and second substantially rigid arch portions inserted into a vacuum device.

FIG. 10 is a perspective view of a flexible plastic storage bag in relation to another embodiment of a vacuum device.

FIG. 11 is a detailed view of the area indicated by circle B-B of FIG. 3 that illustrates one embodiment of interlocking fastening strips that can be included with the plastic storage bag.

FIG. 12 is a view of another embodiment of interlocking fastening strips.

FIG. 13 is a view of another embodiment of interlocking fastening strips.

FIG. 14 is a view of another embodiment showing a textured portion.

FIG. 15 is a view of another embodiment showing a textured portion.

FIG. 16 is a view of another embodiment showing a textured portion.

FIG. 17 is a view of another embodiment showing a textured portion.

FIG. 18 is a view of another embodiment showing a textured portion.

FIG. 19 is a view showing another embodiment showing textured portions.

FIG. 20 is a schematic view illustrating a method of producing a flexible bag having a textured portion.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Referring to FIG. 1, a plastic storage bag 100 is shown in relation to a vacuum device 150. The plastic storage bag 100 includes a first sidewall 102 and an opposing second sidewall 104 overlaying and joined to the first sidewall to provide an interior volume 106 for receiving food items. The first and second sidewalls can be made from a pliable or flexible web of any suitable thermoplastic material generally suitable for food storage. For example, the thermoplastic material can be polyethylene including high density (HDPE), low density (LDPE), linear low (LLDPE), nylon, ethylene vinyl alcohol (EVOH), polypropylene (PP), ethylene vinyl acetate (EVA), polyester, ionomers or metallized films. Moreover, the sidewalls can be single layer or multi-layered materials.

The first and second sidewalls 102, 104 can be joined together along a first side edge 110, a second side edge 112, and a closed bottom edge 114 that extends between the first and second side edges. The edges of the first and second sidewalls can be joined together by a heat sealing operation. To access the interior volume 106, the portions of the first and second sidewalls 102, 104 extending along an open top edge 116 remain un-joined. The plastic storage bag 100 may have a generally rectangular shape. However, it will be appreciated in other embodiments that the bag can have other suitable shapes and sizes. Additionally, in other embodiments, the first and second sidewalls may be gusseted.

To close the open top edge 116, the bag 100 can include first and second interlocking fastening strips 120, 122. The first and second interlocking fastening strips 120, 122 can be made from extruded thermoplastic material and can be attached or joined to the bag proximate the open top edge 116. The first and second interlocking fastening strips 120, 122 have shaped profiles extending over their length that can engage and release with each other to allow for repeated opening and closing of the storage bag. To engage the fastening strips, the fastening strips 120, 122 can be aligned adjacent to each other and pressed together. To release the fastening strips, oppositely directed pulling forces can be applied to the first and second sidewalls 102, 104.

To better preserve food items that may be stored in the plastic storage bag 100, the interior volume 106 can be evacuated with the vacuum device 150. The particular illustrated embodiment of the vacuum device 150, sometimes referred to as a “snorkel” or nozzle type vacuum device, includes a bottom housing 152 and a pivoting lid 154 pivotally attached to the rear of the bottom housing. Enclosed within the bottom housing can be an air flow generating device 156 that can be electrically operated. To interface the air flow generating device 156 with the plastic storage bag 100 during evacuation, the vacuum device also includes a snorkel or nozzle 158 protruding from the bottom housing 152. The nozzle 158 as illustrated can be a cannular tab-like structure with a plurality of air holes disposed therein. The nozzle 158 is in fluid communication with the air flow generating device 156 such that, when operating, air can be drawn through the nozzle and exhausted outside the bottom housing 152.

In use, the plastic storage bag 100 is first inserted into the vacuum device 150 such that the protruding nozzle 158 is received through the open top edge 116 of the storage bag. The bottom housing 152 can include one or more flanges or shoulders 166 to help properly align the open top edge 116 with the nozzle 158 or the device can rely on the aptitude of the user for proper alignment. The lid 154 is then pivoted adjacent to the bottom housing 152 to retain the bag 100 between the lid and bottom housing as illustrated in FIGS. 2 and 3. The air flow generating device is then activated to draw air from the interior volume 106 via the nozzle 158.

To seal closed the open top edge 116 after evacuation, the vacuum device 150 can include lower and upper heating elements 160, 162. Referring to FIGS. 2 and 3, the lower heating element 160 is attached to the bottom housing 152 and the upper heating element 162 is attached to the lid 154 so that, when the plastic storage bag 100 is inserted into the vacuum device, the heating elements generally align with the open top edge 116 of the bag 100. The temperature of the heating elements 160, 162 can be raised through heating to locally melt and seal the open top edge 116 of the bag. The heating may be electrical resistive heating. In those embodiments in which the plastic bag includes first and second interlocking closure strips 120, 122, the closure strips can be located a spaced distance away from the open top edge 116 so as to avoid interfering with the heat sealing process.

In another embodiment, the vacuum device 150 can close the interlocking strips 120, 122, after evacuation. The bottom housing 152 and the lid 154 may include protrusions 170, 172 as shown in FIGS. 2 and 3. The protrusions 170, 172 engage the interlocking strips 120, 122 to close the strips after evacuation. Thus, in one embodiment, the interlocking strips 120, 122 can seal the bag without the use of heat sealing. In another embodiment, the bag can be sealed using heat sealing and the fastening strips. When the user wants to use the contents of the bag, the user can cut-off the heat seal above the interlocking strips and then the user may open the interlocking strips. When the user wishes to seal the bag, the user can close the bag using the interlocking strips by using their fingers or by using the vacuum device.

In various embodiments, the nozzle 158 can be movable so as to extend and retract from the bottom housing portion 152. Specifically, the nozzle 158 can move between the heating elements 160, 162 into the open top edge 116 of the bag. When the nozzle 158 is in the retracted position, the nozzle 158 can be removed from the open top edge 116 and the lid 154 can be pressed toward the bottom housing 152 so that the lower and upper heating elements 160, 162 press upon the first and second sidewalls 102, 104 during the heating operation. The plastic bag can later be cut open to access the stored contents.

As can be appreciated with respect to FIGS. 2 and 3, as the storage bag 100 is evacuated by the vacuum device 150, the first and second sidewalls 102, 104 can collapse adjacent to each other when latent air is removed from the interior volume 106. The sidewalls 102, 104 can collapse in a manner that traps air in other portions of the bag thereby preventing its removal. Additionally, the sidewalls 102, 104 can collapse about the nozzle 158 in a manner that chokes the nozzle 158 preventing further removal of air and which can result in potential damage to the vacuum device. To address the problems with the sidewalls collapsing together, the storage bag can include a separator member that maintains separation of the sidewalls proximate the open top edge.

Referring to the embodiment shown in FIGS. 1-3, the separator member 130 can be comprised of a piece of compressible, open celled foam 132 such as urethane, polyurethane, polyethylene, cellulose, natural rubber, or synthetic rubber. The piece of foam 132 can be attached to the inner surface of the first sidewall 102 by, for example, adhesive, and is generally located between the first and second side edges 110, 112 in close proximity to the opened top edge 116. To ensure that the foam piece 132 does not interfere with heat sealing of the open top edge 116, the foam piece can be set back into the interior volume 106 and away from the very top edge 116 of the bag. Additionally, in the embodiments that include interlocking fastening strips, the foam piece can be located so as to not interfere with their operation as well. The piece of foam 132 can have a thickness, designated by arrows 134, that causes the foam to extend from the inner surface of the first sidewall 102 into the interior volume 106. Because of its location in the bag, when the bag 100 is inserted into the vacuum device 150 the nozzle 158 aligns with and abuts against the piece of foam. As can be appreciated from FIG. 3, when the first and second sidewalls collapse together, the separator member 130 attached to the first sidewall 102 comes into contact with the second sidewall 104 and thereby maintains separation between the two sidewalls. Additionally, because of its open cell structure, air from the interior volume 106 can move through the piece of foam 132 comprising the separator member 130 to the nozzle 158 where the air is withdrawn from the bag.

In one embodiment, the foam 132 can be generally compressible. Compressibility allows the thickness of the foam to gradually decrease as the air is withdrawn from the interior volume and the first and second sidewalls are drawn against the foam. Specifically, over the course of the evacuation process the air pressure within the interior volume will continually decrease resulting in an increasing force pulling the sidewalls together. The characteristics of the foam can be selected so that the compression of the foam occurs toward the end of the evacuation process when air from the interior volume has been substantially removed and that air pressure in the interior volume has been significantly lowered.

Referring now to FIG. 4, there is illustrated another embodiment of a plastic storage bag 200 having another type of separator member 230. The illustrated storage bag includes a first sidewall 202 and an opposite second sidewall 204 overlaying and joined to the first sidewall to provide an interior volume 206. The interior volume 206 can be accessible via an open top edge 216. To evacuate the storage bag 200, the open top edge 216 can be received in a vacuum device 250 having a protruding nozzle 258. To prevent the first and second sidewalls 202, 204 from collapsing about the nozzle in a manner that disrupts evacuation, the spacer member 230 includes a first piece of compressible open-celled foam 232 and a corresponding second piece of compressible open-celled foam 234. The first foam piece 232 is attached to and extends from the inner surface of the first sidewall 202 proximate the open top edge 216. The second piece 234 is attached to and extends upwardly from the inner surface of the second sidewall 204. When the open top edge 216 is inserted into the vacuum device and the first and second sidewalls 202, 204 are pressed between the bottom housing 252 and the pivoting lid 254, the lower and upper foam pieces 232, 234 may engage the nozzle 258. Because of the open-celled nature of the foam pieces, air from the interior volume can still access the nozzle.

The separator member may be made of other materials. For example, referring to FIGS. 5 and 6, there is illustrated the open top edge 316 of a thermoplastic bag 300 having a separator member in the form of an open ended tube 330. The tube 330 may be attached to the inner surface of the first sidewall 302 and may be located between the first and second side edges 310, 312. The tube 330 can extend through the interior volume 306 from a position proximate the open top edge 316 toward the closed bottom edge 314 and may be open at both ends. Further, the tube 330 can be sized to receive a nozzle of the vacuum device described herein. Thus, when the storage bag 300 is inserted into the vacuum device, the nozzle can communicate with various portions of the interior volume 306 via the tube 330.

The tube 330 can be made from any suitable material including a rigid or a semi-rigid thermoplastic material. The thermoplastic material of the tube 330 can be more rigid than the thermoplastic material of the bag sidewalls 302, 304. Thus, as the sidewalls 302, 304 begin to collapse during evacuation, the tube 330 can substantially maintain its shape for at least a portion of the duration of evacuation. Thus, the tube may maintain separation between the sidewalls and facilitates communication between the interior volume and the vacuum device. In an embodiment, the material of the tube can be selected so as to collapse at the end of evacuation after most air has been removed to reduce the overall size and bulk of the storage bag.

Referring to FIG. 7, there is illustrated in top plan view the open top edge 416 of another embodiment of a plastic storage bag 400 having a separation member in the form of a corrugated area 430 which may be formed with the inner surface of the first sidewall 402. The corrugated area 430 may be comprised of a plurality of corrugation ribs 432 that depend from the inner surface of the first sidewall into the interior volume 406. The corrugation ribs 432 can extend from proximate the open top edge 416 toward the closed bottom edge of the storage bag 400. During evacuation, when the storage bag 400 is inserted into a vacuum device the corrugated area 430 can align with the nozzle of the vacuum device. As the first and second sidewalls 402, 404 collapse against themselves and the nozzle, air from the interior volume 406 can continue to access the nozzle via the gaps provided between the corrugation ribs 432. Thus, the corrugated area may maintain some separation between the sidewalls and the nozzle proximate the open top edge.

The corrugation area can be made from any suitable material including, for example, compressible foam, pliable thermoplastic, rigid thermoplastic or semi-rigid thermoplastic. In other embodiments, the corrugated material need not be compressible but could also be rigid or semi-rigid in terms of hardness. Moreover, the corrugated area can be made as a separate piece of material and later attached to the first sidewall by, for example, adhesive or could be integrally formed as part of the first sidewall by, for example, a molding or extrusion process.

Referring to FIGS. 8 and 9, there is illustrated another embodiment of a storage bag 500 having a separation member 530 in the form of a first and second substantially rigid arch portions 532, 534. The arch portions 532, 534 may be formed with the first and second sidewalls 502, 504 generally proximate the open top edge 516 and may protrude slightly outward from the plane of the sidewalls and the interior volume 506. The arch portions may be relatively stiffer than the thermoplastic material of the sidewalls. Referring to FIG. 9, the storage bag 500 may be inserted into a vacuum device 550. During evacuation, the sidewalls 502, 504 collapse, however, the first and second arch portions 532, 534 may maintain a gap within the interior volume 506 proximate the nozzle 558. Separation between the sidewalls with each other and the nozzle may be maintained in the region of the open top edge. Thus, air in other portions of the interior volume 506 can continue to access the nozzle 558 to be withdrawn from the bag 500.

The first and second arch portions can be comprised from any suitable material including thermoplastic having a relatively higher modulus of rigidity than the other sidewall material. Moreover, the arch portions can be made as separate inserts that are later attached to the respective first and second sidewalls or can be formed integrally with the sidewall material by, for example, a suitable molding or extrusion process. While the illustrated embodiment includes arch portions on both the first or second sidewalls, it will be appreciated that the arch portions can be included with only one of the two sidewalls. Moreover, in one or more embodiments, the arch portions can be made of a material of a selected stiffness such that the arch portions will collapse adjacently about nozzle toward the end of the evacuation process to reduce the overall bulk of the evacuated storage bag.

Referring to FIG. 10, there is illustrated another embodiment of a storage bag 600 shown inserted into a vacuum device 650. The illustrated storage bag 600 includes a separator member 630 formed with either the first or second sidewalls 602, 604 and generally proximate the open top edge 616. To maintain separation of the first and second sidewalls 602, 604 during evacuation, the separator member can be of any of the aforementioned types and/or materials. However, in the illustrated embodiment, the separator member 630 extends completely between the first and second joined side edges 610, 612 rather than being located in between and spaced from the side edges. This particular configuration of the separator member reduces the need for precise alignment with the nozzle.

In FIG. 10, the illustrated vacuum device 650 can also be a “chamber” type vacuum device 650. This type of device includes a bottom housing 652 and a pivoting lid 654 pivotally attached to the bottom housing 652. An air flow generating device can be included in the bottom housing 652 for withdrawing air from the storage bag 600 during evacuation. However, rather than including a nozzle to interface with the storage bag, the chamber type vacuum device 650 includes a depression or chamber 664 formed within the upper surface of the bottom housing 652 that can positionally correspond to the open top edge 616 when the storage bag 600 is inserted into the vacuum device. The chamber 664 can be in fluid communication with the air flow generating device. During evacuation, the pivoting lid 654 is pivoted adjacent to the lower housing 652 to trap the plastic storage bag 600 therebetween. The air flow generating device is activated and air from the interior volume of the bag 600 is drawn through the open top edge 616 into the chamber 664 of the device. The chamber type vacuum device 650 can also include upper and lower heating elements 660, 662 to heat seal closed the open top edge 616 of the storage bag after evacuation of the interior volume.

In those embodiments in which the above described plastic storage bag includes interlocking fastening strips, any suitable type of fastening strips can be employed. For example, referring to FIG. 11, there is illustrated one example of interlocking fastening strips that can be used with the storage bag. The illustrated fastening strips 702, 704 may be referred to as “U-channel” style fastening strips. The first fastening strip 702 is formed with a male closure profile 710 that projects from a flat base member 740 that may be adapted to be attached to an inner surface of the first sidewall. The projecting male closure profile 710 may include first and second projections 742, 744 that are generally parallel to and spaced-apart from each other a first distance. Formed at the distal tip of each projection 742, 744 are respective first and second hooks or barbs 746, 748 that are generally directed back toward the base member 740. Moreover, the barbs 746, 748 are directed oppositely or away from each other. The distal most surface of the barbs 746, 748 are generally shaped or rounded to provide respective first and second guide surfaces 750, 752. It will be appreciated that the male closure profile 710 including the first and second projections 742, 744 may extend substantially over the entire length of the first fastening strip 702.

The second fastening strip 704 of the pair illustrated in FIG. 11 may be formed as a female closure profile 712 that likewise projects from a flat base member 760 that may be adapted to be attached to an inner surface of the second sidewall. The projecting female closure profile 732 may include first and second projections 762, 764 that are parallel to and spaced-apart from each other a second distance. The second distance may be slightly greater than the first distance so that the female closure profile 732 is adapted to receive the projections 742, 744 of the male closure profile 730. Formed at the distal tip of each projection 762, 764 of the female closure profile 732 are respective first and second hooks or barbs 766, 768 that are generally directed back toward the base member 760. Furthermore, the barbs 766, 768 are facing and directed towards each other. The distal most surface of the barbs 766, 768 are generally shaped or rounded to provide respective first and second guide surfaces 770, 772. Additionally, the female closure profile 732 may also include a flange 774 projecting from the base member 760 approximately midway between the first and second projections 762, 766 that extends to approximately the same height as the first and second projections. In other embodiments, the closure profile may not include the flange 774. It will be appreciated that the female closure profile 732 including the first and second projections 762, 764 may extend substantially over the entire length of the second fastening strip 704.

To engage the male and female closure profiles 730, 732 as illustrated in FIG. 11, the first and second interlocking fastening strips 702, 704 are pressed toward each other until the guide surface 750, 752 on the male projections 742, 744 contact the guide surfaces 770, 772 on the female projections 762, 764. Due to the flexible characteristic of the thermoplastic fastening strip material, contact between the guide surfaces causes the male projections 742, 744 to flex inwardly and the female projections 762, 764 to flex outwardly. The barbs 746, 748 on the male projections 742, 744 and the barbs 766, 768 on the female projections 762, 764 can thereby slide past each other. Once past each other, the flexible characteristic of the fastening strip material causes the male and female projections to flex back moving the barbs into an interlocking engagement with each other. Furthermore, because of the flexible and resilient characteristics of the fastening strip material, a sufficient, oppositely applied pulling force can disengage the male and female closure profiles.

In another embodiment illustrated in FIG. 12, the interlocking fastening strips employed can be such as those disclosed and described in U.S. Pat. No. 5,664,299, herein incorporated by reference in its entirety. The fastening strips may be referred to as “profile” style fastening strips. The interlocking fastening strips 802, 804, may include a first closure profile 810 projecting from a base member 820 of the first fastening strip 802 adapted to engage a corresponding second closure profile 812 projecting from a base member 822 of the second fastening strip 804. The first and second closure profiles 810, 812 of the fastening strips 802, 804 can be made from any suitable, semi-flexible thermoplastic material and can be manufactured by, for example an extrusion process.

The first closure profile 810 includes a first pair of projections 824, 826 projecting from the base member 820 that are parallel and spaced-apart from each other a first distance. Formed on the distal ends of each of the first projections 824, 826 are respective first hook-like barbs 830, 832 which are pointed generally back toward the base member 820. Moreover, the projections are shaped so that the barbs are arranged in the same direction. The distal most surface of the first projections are generally rounded or shaped to provide first guide surfaces 834, 836.

The second closure profile 812 also includes a pair of second projections 840, 842 projecting from the base member 822 and that are parallel and spaced-apart from each other a second distance. The second distance between the second projections 840, 842 dimensionally corresponds to the first distance between the first projections 824, 826. Formed on the distal ends of the second projection 840, 842 are respective second hook-like barbs 844, 846 which are generally pointed back toward the base member 822. Moreover, the second projections 840, 842 are shaped so that the second barbs are arranged in the same direction and opposite the direction of the first barbs 830, 832. The distal most surfaces of the second projections are generally rounded or shaped to provide second guide surfaces 850, 852.

To engage the first and second closure profiles of FIG. 12, the first and second fastening strips 802, 804 are pressed together so that the first projections 824, 826 abut the correspondingly spaced-apart second projections 840, 842. Particularly, the first guide surfaces 834, 836 contact the second guide surfaces 850, 852 causing the first projections 824, 826 and second projections 840, 842 to flex such that the first barbs 830, 832 and oppositely directed second barbs 844, 846 slide about each other and engage. Hence, the first and second fastening strips 802, 804 are hooked together. To disengage the first and second fastening strips 802, 804, a sufficient pulling force is applied which causes the flexible projections to displace and release each other.

Referring to FIG. 13, there is illustrated in cross-section fastening strips 902, 904 such as those disclosed in U.S. Pat. No. 3,806,998, herein incorporated by reference in its entirety. These fastening strips may be referred to as “arrow-head” or “rib and groove” style fastening strips. The first fastening strip 902 may have a projecting head portion 920 extending from a flat base member 922. The head portion 920 includes a mushroom-shaped head 924 that is located at the end of a reduced neck portion 926 that is connected to the base member 922. The second fastening strip 904 may include a base member 932 and a C-shaped groove portion 930. The projecting head portion 920 of the first fastening strip 902 is receivable in the groove portion 930 of the second fastening strip 904. Through this arrangement, the fastening strips 902, 904 are adapted to be interlockingly engaged when pressed together and separated by being pulled apart.

In some embodiments, one or both sidewalls can have textured portion. In the embodiment illustrated in FIG. 14, the inner surface 1009 of the sidewall 1004 may have a textured portion 1090. The textured portion 1090 may include peaks 1092 that can be formed along the crests of a first plurality of raised ridges 1100 that extend along the inner surface. The first plurality of ridges 1100 can be arranged parallel to and spaced-apart from each other. The recesses 1102 are therefore defined within the clearances between the ridges 1100. In the illustrated embodiment, a second plurality of parallel ridges 1106 extends along the inner surface normal to and intersecting the first plurality of ridges 1100 to form a grid-like pattern. In an alternative embodiment, the recesses can be formed within a grid-like pattern of grooves disposed into the inner surface, thus forming the raised peaks as a series of protuberances separated by the grooves. For example, in the embodiment illustrated in FIG. 15, the textured portion may include a first and a second plurality of grooves 1112, 1113 which are disposed into the inner surface 1009 and are arranged orthogonally to each other. The grooves 1112, 1113 define a plurality of raised portions 1114 that are square in shape. It will be appreciated that air can communicate along the grooves 1112, 1113 between the raised portions 1114 even after the sidewalls have been collapsed together. In another embodiment illustrated in FIG. 16, the textured portion 1090 can include protuberances 1108 having smaller, circular shapes that are randomly dispersed along the inner surface 1009 that are segregated from each other by arbitrarily-shaped recessed spaces 1110 therebetween. Of course, the textured portion can have any other suitable shape, such as diamond-shaped ridges or grooves, horizontally arranged ridges or grooves, vertically arranged ridges or grooves, patterned or random curved-shaped ridges or grooves, etc.

Referring to FIG. 1, the textured portion can be provided over substantially the entire second inner surface of the sidewall 104 between the first and second side edges 110, 112 and between the closed bottom edge 114 and fastening strips 120, 122. Moreover, the first inner surface of the first sidewall 102 can likewise be provided with a textured portion. A benefit of providing the textured portion is that the recesses extend over the inner surface and are interconnected with one another. Accordingly, air within the internal volume 106 can access the top of the bag along the interconnected recesses even as the opposing first and second sidewalls 102, 104 collapse together, thereby preventing air in the internal volume from becoming trapped.

Of course, in other embodiments, the textured portion need not be provided over substantially the entire inner surface. For example, in the embodiment illustrated in FIG. 17, the textured portion is provided as a relatively narrow, vertical strip 1120 on the second sidewall 1004 arranged to correspond to the separator member 1030. The remainder of the second inner surface may be formed as a substantially smooth portion 1122. In another embodiment illustrated in FIG. 18, the textured portion is provided as a T-shape 1124 having a horizontal strip 1126 and an intersecting vertical strip 1128. The horizontal strip 1126 extends between the first and second side edges 1010, 1012 while being spaced-apart from the bottom edge 1016. The vertical strip 1128 extends between the bottom edge 1016 and the horizontal strip 1126 while being spaced-apart from the first and second side edges 1010, 1012. Accordingly, the T-shape textured portion 1124 can extend substantially throughout the internal volume 1006 between the opposing side edges 1010, 1012 and the top and bottom edges 1014, 1016 while substantially smooth portions 1130, 1132 may be provided.

In another embodiment illustrated in FIG. 19, to maximize exhaustion of the flexible bag wherein the textured portion is located on both the first and second sidewalls 1002, 1004, the peaks 1134 and recesses 1136 can be arranged and sized to cooperate so as to minimize the remaining internal volume as the sidewalls collapse together. For example, the peaks 1134 located on each sidewall are received in corresponding recesses 1136 formed on the opposing sidewall to interlock together.

To produce a flexible bag having a textured portion, webs of flexible thermoplastic material can be manipulated through a high speed manufacturing process such as that illustrated in FIG. 20. In the manufacturing process, a first web 1140 of thermoplastic material is continuously unwound from a roll 1142 and aligned in and advanced along a machine direction 1144 through the processing machines. The first web of material 1140 accordingly has a first surface 1146 and a second surface 1148.

A second web 1150 of thermoplastic material is provided wound onto a second roll 1152 located below the first roll. Embossed into the material of the second web 1150 are pluralities of peaks and recesses that form the textured portion of the finished flexible bag. The second web 1150 is continuously unwound from the second roll 1152 and aligned with the machine direction 1144 where it is attached to the second surface 1148 of the advancing first web 1140 by web attachment rollers 1154. As will be appreciated, the attached first and second webs 1140, 1150 will form the second sidewall of the finished flexible bag.

To provide the first sidewall, a third web 1160 of thermoplastic material is provided wound onto roll 1162. The third web 1160 is continuously unwound and aligned with the first and second webs 1140, 1150 in the machine direction 1144. After alignment, the third web 1160 is attached to the first and second webs 1140, 1150 at a second set of web attachment rollers 1164. In order to form the open top edge of the finished bag, the third web 1160 is only attached to the first and second webs 1140, 1150 along a first edge 1168 of the combined webs while the parallel second edge 1169 remains unattached.

To provide the fastening strips on the finished bag, the first and second fastening strips 1170, 1172 can be provided as elongated thermoplastic extrusions wound onto first and second strip rolls 1174, 1176. The first fastening strip 1170 is unwound and aligned with the third web 1160 to which the first fastening strip is attached by strip attachment rollers 1178. The second fastening strip 1172 is unwound and aligned in the machine direction 1144 with the first and second webs to which the second fastening strip is continuously attached by strip rollers 1180. As illustrated in FIG. 20, the first and second fastening strips 1170, 1172 are aligned with the unattached second edge 1169 of the combined webs. Preferably, attachment of the fastening strips to the continuously advancing webs of thermoplastic material occurs between the first and second web attachment rollers 1154, 1164. In another embodiment, the fastening strips can be extruded directly onto the webs.

As the attached webs and strips are advanced in the machine direction 1144, the side edges and bottom edge of the finished bag may be produced by an edging machine 1182. Specifically, the edging machine 1182 forms a seal 1184 across the width of the webs and the bottom of the webs. The cutting machine 1186 then cuts the webs along the seal to form individual bags 1188.

In another embodiment, instead of providing the textured portion in the form of a separate web of material, the textured portion can be formed directly onto the first web 1140 of advancing material. For example, the second roll 1152 and second web 1150 of material can be eliminated and the first web attachment rollers 1154 can be replaced with an embossing machine that forms the peaks and recesses directly onto the first web 1140. In another embodiment, the third web 1160 can be eliminated and the first web 1140 can be folded over to form the sidewalls of the bag. The textured portion may be applied or formed either before or after the folding process.

All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

Exemplary embodiments of this invention are described herein. Variations of those embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor(s) expect skilled artisans to employ such variations as appropriate, and the inventor(s) intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims

1. A system for vacuum storing food items comprising:

a plastic storage bag including a first flexible thermoplastic sidewall, a second flexible thermoplastic sidewall overlying and joined to the first sidewall to provide an interior volume, the interior volume accessible via un-joined open top edges of the first and second sidewalls, the storage bag further comprising a separator member located proximate the opening for separating the first and second sidewalls; and

a vacuum device including a bottom housing, a pivoting lid pivotally attached to the bottom housing, and an airflow generating device.

2. The system of claim 1, wherein the separator member is substantially rigid.

3. The system of claim 1, wherein the separator member is compressible.

4. The system of claim 1, wherein the separator member is a piece of compressible foam attached to the first sidewall.

5. The system of claim 1, wherein the separator member is a corrugated area formed with the first sidewall.

6. The system of claim 1, wherein the separator member is a tube.

7. The system of claim 1, wherein the separator member is a comparatively rigid arch portion formed with the first sidewall.

8. The system of claim 1, further comprising first and second interlocking closing strips attached respectively to the first and second sidewalls proximate the opening.

9. The system of claim 1, wherein the vacuum device includes a nozzle, the nozzle receivable in the opening of the storage bag and communicating with the airflow generating device.

10. The system of claim 1, wherein the vacuum device includes a first heating element attached to the bottom housing and a second heating element attached to the lid, the first and second heating elements adapted to apply localized heating proximate the un-joined open top edges of the plastic storage bag.

11. The system of claim 1, wherein one of the sidewalls has a textured portion.

12. A method of evacuating a plastic storage bag comprising:

(i) providing a storage bag having first and second flexible plastic sidewalls joined together to provide an interior volume for receiving food items, the interior volume accessible via an opening disposed between the sidewalls, the storage bag further having a separator member proximate the opening;

(ii) inserting the storage bag into a vacuum device;

(iii) evacuating the interior volume such that the first and second sidewalls substantially collapse adjacent to each other; and

(iv) maintaining separation of the first and second sidewalls proximate the opening with the separator member.

13. The method of claim 12, further comprising the step of:

(v) sealing closed the opening with a heating element of the vacuum device.

14. The method of claim 12, wherein the vacuum device includes a nozzle for withdrawing air from the storage bag.

15. The method of claim 14, further comprising the step of:

(v) aligning the separator feature with the nozzle.