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STORAGE BAG WITH FLUID SEPARATOR
FIELD OF THE INVENTION
This invention pertains generally to storage containers and more particularly to flexible, thermoplastic, storage bags designed to be sealed and evacuated. The invention finds particular applicability in the field of food storage.
BACKGROUND OF THE INVENTION
Storage bags are commonly used for a variety of purposes such as storing food items. Such storage bags are typically made from a flexible, low cost, thermoplastic material that defines an interior volume into which food items can be inserted. To preserve the inserted food, the storage bag may also include a distinct closing mechanism, such as interlocking fastening strips, for sealing closed an opening through which the interior volume is accessible.
One problem that occurs with the aforementioned storage bags is that latent air may remain trapped within the interior volume after sealing closed the opening. The trapped air may cause spoiling or dehydration of the food items. To remove the trapped air, it is known to provide a one-way valve element or other evacuation device communicating with the interior volume. The one-way valve element allows for the evacuation of trapped air while preventing the ingress of air from the surrounding volume into the interior volume. The one-way valve element may be activated in various ways such as, for example, by applying compressive pressure to the flexible sidewalls to force air from the interior volume or by engaging a nozzle of a vacuum source to or about the one-way valve element to draw air from the interior volume.
Often, the stored food items contain fluids or juices that, during evacuation, may be drawn into and thereby contaminate the valve element. As will be appreciated, the contaminated valve element may result in sanitary issues and may not function properly. Additionally, the fluids or juices may also be drawn through the valve element and into the vacuum source or otherwise ejected into the environment, causing additional sanitary or operational problems. The inventive storage bag remedies these and other problems.
BRIEF SUMMARY OF THE INVENTION
The invention provides a storage bag configured with a separator that causes separation of fluids and juices from air being evacuated through the one-way valve element. The valve element communicates with the interior volume via the separator such that evacuating air must pass through the separator. By removing fluids and juices from the evacuating air before the air passes through the one-way valve element, contamination of the valve element is avoided.
In an aspect of the invention, the separator is configured as an excess piece of flexible material that sealingly connects the valve element to a smooth sidewall of the storage bag. The flexible separator is adjustable between a collapsed position and an expanded position. In the collapsed position, the valve element is generally located within the plane of the sidewall to enable compact stacking and folding of multiple bags. In the expanded position, the separator expands to define a chamber that raises or spaces the valve element from the sidewall. As air is drawn through the chamber, fluids and juices are caused to gravitationally separate from the evacuating air, condense together, and are returned to the interior volume.
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An advantage of the invention is that it provides a storage bag configured to prevent contamination of a one-way valve element by separating fluids from evacuating air. Another advantage is that, in an aspect, the bag including the separator 5 is made from flexible material to allow collapsing and folding of the bag for compact packaging during distribution. These and other advantages and features of the invention will become apparent from the detailed description and the accompanying drawings.
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BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a storage bag designed in accordance with the teachings of the invention, the storage 15 bag having a one-way valve element and a separator for separating fluids and juices from evacuating air.
FIG. 2 is a cross-sectional view through the valve element and the separator as taken along line 2-2 of FIG. 1, the valve element and separator being acted upon by a nozzle during 20 evacuation and the separator shown in an expanded position.
FIG. 3 is a cross-sectional view through the valve element and the separator as taken along line 3-3 of FIG. 1, the separator shown in a collapsed position.
FIG. 4 is an exploded view of another embodiment of a 25 storage bag having a one-way valve element and a separator for separating fluids and juices from evacuating air.
FIG. 5 is a cross-sectional view through the valve element and separator taken along line 5-5 of FIG. 1, the valve element and separator being acted upon by a nozzle during evacuation 30 and the separator shown in an expanded position.
FIG. 6 is a cross-sectional view through the valve element and the separator as taken along line 6-6 of FIG. 4, the separator shown in a collapsed position.
FIG. 7 is a cross-sectional view of another embodiment of 35 the storage bag as taken through the valve element and the separator as being acted upon by a nozzle during evacuation, the separator shown in the expanded position.
FIG. 8 is a cross-sectional view of the embodiment of the storage bag illustrated in FIG. 7 as taken through the valve 40 element and the separator, the separator shown in the collapsed position.
FIG. 9 is a perspective view of another embodiment of the storage bag having a one-way valve element and a separator for separating fluids and juices from evacuating air, where the 45 separator is provided by forming opposing Z-folds into the sidewall of the bag.
FIG. 10 is a detailed view of the indicated portion of FIG. 9, illustrating the arrangement of the opposing Z-folds.
FIG. 11 is a cross-sectional view through the valve element 50 and separator taken along line 11-11 of FIG. 9 with the separator shown in the collapsed position.
FIG. 12 is a cross-sectional view through the valve element and separator taken along line 12-12 of FIG. 9 with the separator shown in the expanded position.
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DETAILED DESCRIPTION OF THE INVENTION
Now referring to the drawings, wherein like reference numbers refer to like elements, there is illustrated in FIG. 1 a
60 storage bag 100 for storing items such as food stuffs. In the illustrated embodiment, the storage bag 100 is made from a first sidewall 102 and an opposing second sidewall 104 overlying the first side wall to define an interior volume 106 therebetween. The first and second sidewall 102, 104 are
65 joined along a first side edge 110, a parallel or non-parallel second side edge 112, and a closed bottom edge 114 that extends between the first and second side edges. The first and
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second sidewalls 102,104 are preferably made from a flexible or pliable thermoplastic material formed or drawn into a smooth, thin walled sheet. Examples of suitable thermoplastic material include high density polyethylene, low density polyethylene, polypropylene, ethylene vinyl acetate, nylon, 5 polyester, polyamide, ethylene vinyl alcohol, and can be formed in single or multiple layers. The thermoplastic material can be transparent, translucent, opaque, or tinted. Furthermore, the material used for the sidewalls can be a gas impermeable material. The sidewalls 102,104 can be joined along 10 the first and second side edges 110,112 and bottom edge 114 by any suitable process such as, for example, heat sealing.
For accessing the interior volume 106, the top edges 120, 122 of the first and second sidewalls 102, 104 opposite the bottom edge 114 remain un-joined to define an opening 124. 15 To seal closed the opening 124, first and second interlocking fastening strips 126, 128 can be attached to the interior surfaces of the respective first and second sidewalls 102, 104. The first and second fastening strips 126, 128 extend generally between the first and second side edges 110,112 parallel 20 to and spaced below the top edges 120,122. In other embodiments, the bag 100 can include a movable slider straddling the fastening strips 126,128 to facilitate occluding and deoccluding of the opening 124. In other embodiments, instead of fastening strips, the first and second sidewalls can be config- 25 ured with pressure sensitive or cold seal adhesives (such as those disclosed in U.S. Pat. No. 6,149,304, herein incorporated by reference in its entirety), heat-sealing, or cling, to seal the open top edge.
To evacuate the bag of latent or entrapped air after the 30 opening has been sealed closed, a one-way valve element 130 is provided that communicates with the interior volume 106. In one embodiment, the one-way valve element 130 is configured to open under an applied pressure differential thereby allowing air from the interior volume 106 to escape and to 35 close after elimination or reduction of the pressure differential thereby preventing the ingress of environmental air into the interior volume. In accordance with the invention, the one-way valve element is connected to the rest of the bag via a separator to separate fluids and juices from evacuating air. 40
As illustrated in FIGS. 1 and 2, the separator 132 is formed from a piece of excess material in the shape of a thin-walled dome 134 that is joined along its base to a first sidewall 102 and protrudes outward therefrom. The thin-walled dome 134 of excess material surrounds and defines an enclosed cham- 45 ber 136 that communicates with the interior volume 106. The valve element 130 is sealingly joined to the apex of the dome 134 and is thereby connected to and spaced-apart from the first sidewall 102.
Referring to FIG. 2, air drawn or forced from the interior 50 volume 106 must pass through the chamber 136 to reach and escape through the valve element 130. In the chamber 136, fluids and juices entrained in the evacuating air from the interior volume are removed by gravitational separation and returned to the interior volume 106. More specifically, the 55 pressure, velocity, and generally vertical direction of the air being drawn or forced through the chamber 136 interact to cause the fluids and juices to condense into droplets that can remain in the chamber during evacuation and return under the influence of gravity to the interior volume 106. This is facili- 60 tated by the greater density of the fluids as compared to air and due to the resulting condensation droplets' inability to traverse the chamber. Additionally, contacting the evacuating air generally along the inner surfaces of the sidewalls 102, 104 and causing the evacuating air to turn towards the valve 65 element 130 along the inner surface of the excess material making up the separator 132 facilitates separation and con
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densation of the fluids and juices. Hence, the evacuating air actually passing through the valve element 130 is relatively devoid of entrained fluids and juices in liquid or droplet form, thereby preventing contamination of the valve element. The size and shape of the chamber 136 can be optimized with respect to the shape of the interior volume 106, first sidewall 102, and valve element 130 to maximize the separation of fluids and juices.
Referring to FIGS. 2 and 3, to allow for folding and packaging of the storage bag 100, the separator 132 is preferably adjustable between a collapsed position and an expanded position. The separator 132 can be made from the same or similar flexible or pliable material as the first or second sidewalls 102, 104. When the bag 100 is placed atop a generally flat surface, the separator 132 can collapse from the dome shape and bunch or fold together about the valve element 130 so that the valve element is generally located within the plane of the first sidewall 102, as shown in FIG. 3. When the separator 132 is in the collapsed position, the chamber is by and large eliminated. Hence, the first and second sidewalls 102, 104 are generally parallel and can be pressed together to eliminate the interior volume 106 and flatten the bag 100. As will be appreciated, multiple flattened bags can be compactly stacked atop one-another for packaging and distribution.
In one embodiment, to make the separator 132 "pop-up" and thereby place the separator into its expanded position, referring back to FIG. 2, a pressure differential is applied across the first sidewall 102 proximate the valve element 130. The pressure differential can be generated by the same vacuum source used to evacuate air from the bag 100 or from a different vacuum source. Specifically, a generally tubular nozzle 140 is placed against the first sidewall 102 generally about the valve element 130 and the separator 132. The first end of the nozzle 140 can be pressed against the first sidewall 102 while the second end of the nozzle communicates with a vacuum source. When the vacuum source is activated, the pressure differential between the interior volume 106 and the nozzle 140 causes the separator 132 to expand and protrude in the shape of the thin-walled dome 134 from the first sidewall 102. The expanding separator 132 defines the chamber 136 that raises or spaces the valve element 130 apart from the first sidewall 102 and in which the separation of fluids and juices from the evacuating air occurs. After evacuation of the interior volume 106, the valve element 130 will close as the pressure differential is reduced or eliminated and the nozzle 140 can be removed. After removal of the nozzle, the separator 132 can be collapsed by vacuum from inside the bag or by external hand pressure to force the remaining air in the chamber 136 back into the interior volume. In other applications, it will be appreciated that, rather than using a nozzle and an attached vacuum source, evacuation of the interior volume can occur by pressing the first and second sidewalls together by hand thereby forcing air into and expanding the separator.
Referring to FIGS. 2 and 3, the excess material for the separator 132 is preferably provided from the same sheet of material as used for the first sidewall 102. For example, the pliable material of the first sidewall 102 can be stamped, thermoformed or otherwise displaced or formed to provide the dome-shape 134 of the separator 132. Hence, the separator 132 is integral with the first sidewall 102 and can likewise be made of any suitable thermoplastic material such as, for example, high density polyethylene, low density polyethylene, polypropylene, ethylene vinyl acetate, and can be formed in single or multiple layers.
Referring to FIG. 4, there is illustrated another embodiment of a storage bag 200 wherein the separator 232 has a generally tubular shape and is formed separately from the
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