U.S. patent application number 12/420195 was filed with the patent office on 2009-10-15 for flexible storage bag with vent between two zipper.
This patent application is currently assigned to ILLINOIS TOOL WORKS INC.. Invention is credited to Victor Matias.
Application Number | 20090257685 12/420195 |
Document ID | / |
Family ID | 41164046 |
Filed Date | 2009-10-15 |
United States Patent
Application |
20090257685 |
Kind Code |
A1 |
Matias; Victor |
October 15, 2009 |
FLEXIBLE STORAGE BAG WITH VENT BETWEEN TWO ZIPPER
Abstract
A bag comprising a receptacle and first and second reclosable
structures installed inside and across a mouth of the receptacle,
the first and second reclosable structures being parallel and
spaced apart from each other. At least portions of the first and
second reclosable structures bound a passageway within the mouth of
the receptacle when the first and second reclosable structures are
in fully closed states. The receptacle comprises a vent that is in
flow communication with an interior volume of the receptacle via
the passageway when both the vent and the first reclosable
structure are in at least partially open states. If, while the
first and second reclosable structures are in fully closed states,
the pressure inside the interior volume is increased sufficiently,
the first reclosable structure will open at least partly to allow
gas from the interior volume to escape into the passageway while
the second reclosable structure remains in a fully closed
state.
Inventors: |
Matias; Victor; (New
Braunfels, TX) |
Correspondence
Address: |
OSTRAGER CHONG FLAHERTY & BROITMAN PC
570 LEXINGTON AVENUE, FLOOR 17
NEW YORK
NY
10022-6894
US
|
Assignee: |
ILLINOIS TOOL WORKS INC.
Glenview
IL
|
Family ID: |
41164046 |
Appl. No.: |
12/420195 |
Filed: |
April 8, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61044541 |
Apr 14, 2008 |
|
|
|
Current U.S.
Class: |
383/38 ; 383/103;
383/120 |
Current CPC
Class: |
B65D 33/2566 20130101;
B65D 77/225 20130101 |
Class at
Publication: |
383/38 ; 383/103;
383/120 |
International
Class: |
B65D 30/22 20060101
B65D030/22; B65D 33/01 20060101 B65D033/01; B65D 30/20 20060101
B65D030/20 |
Claims
1. A bag comprising a receptacle and first and second reclosable
structures installed inside said receptacle, said first reclosable
structure bounding an interior volume for product inside said
receptacle when said first reclosable structure is in a fully
closed state, and at least portions of said first and second
reclosable structures bounding a first passageway inside said
receptacle when said first and second reclosable structures are in
fully closed states, said receptacle comprising a first vent that
is in flow communication with said interior volume via said first
passageway when both said first vent and said first reclosable
structure are in at least partially open states, wherein if, while
said first and second reclosable structures are in fully closed
states, the pressure inside said interior volume is increased
sufficiently, said first reclosable structure will open at least
partly to allow gas from said interior volume to escape into said
first passageway while said second reclosable structure remains in
a fully closed state.
2. The bag as recited in claim 1, wherein at least portions of said
first and second reclosable structures bound a second passageway
inside said receptacle when said first and second reclosable
structures are in fully closed states, said receptacle further
comprising a second vent that is in flow communication with said
interior volume via said second passageway when both said second
vent and said first reclosable structure are in at least partially
open states.
3. The bag as recited in claim 1, wherein said receptacle comprises
first and second walls, said first reclosable structure comprises
first and second closure profiles, and said second reclosable
structure comprises third and fourth closure profiles, said first
and second closure profiles being mutually engageable to close said
first reclosable structure, and said third and fourth closure
profiles being mutually engageable to close said second reclosable
structure.
4. The bag as recited in claim 3, wherein said first vent comprises
an opening or slit located on said first wall at an elevation
between said first and second reclosable structures.
5. The bag as recited in claim 3, wherein said first and second
walls are joined to each other in first and second marginal
portions disposed along a first side edge of said receptacle, said
first and second marginal portions being separated by a gap where
said first and second walls are not joined to each other,
respective portions of said first and second walls at said gap
forming said first vent.
6. The bag as recited in claim 3, wherein said first and third
closure profiles project from a first base strip joined to said
first wall, and said second and fourth closure profiles project
from a second base strip joined to said second wall.
7. The bag as recited in claim 6, wherein respective portions of
said first and second base strips, disposed adjacent a first side
edge of said receptacle, are not joined to each other and form said
first vent.
8. The bag as recited in claim 6, wherein said first passageway has
a serpentine shape, a part of a boundary of said first passageway
being formed by a seal, said seal being a zone where said first and
second base strips are sealed together.
9. The bag as recited in claim 3, wherein said first passageway has
a serpentine shape, a part of a boundary of said first passageway
being formed by a seal, said seal being a zone where said first and
second walls are sealed together.
10. The bag as recited in claim 1, further comprising a third
reclosable structure installed inside said receptacle, wherein said
third reclosable structure divides said interior volume into first
and second chambers when said first and third reclosable structures
are in fully closed states.
11. The bag as recited in claim 3, wherein said receptacle further
comprises a bottom gusset.
12. A bag comprising a receptacle and first, second and third
reclosable structures installed inside said receptacle, said first
reclosable structure bounding a first interior volume inside said
receptacle when said first reclosable structure is in a fully
closed state, said first and second reclosable structure bounding a
second interior volume inside said receptacle when said first and
second reclosable structures are in fully closed states, and at
least portions of said second and third reclosable structures
bounding a first passageway inside said receptacle when said second
and third reclosable structures are in fully closed states, said
receptacle comprising a first vent that is in flow communication
with said second interior volume via said first passageway when
both said first vent and said second reclosable structure are in at
least partially open states, wherein if, while said first
reclosable structure is in a fully closed state, the pressure
inside said first interior volume is increased sufficiently, said
first reclosable structure will open at least partly to allow
mixing of the contents of said first and second interior volumes,
and wherein if, while said first reclosable structure is in a
partially open state and said second and third reclosable
structures are in fully closed states, the pressure inside said
interior volume is further increased sufficiently, said second
reclosable structure will open at least partly to allow gas from
said second interior volume to escape into said first passageway
while said third reclosable structure remains in a fully closed
state.
13. The bag as recited in claim 12, wherein at least portions of
said second and third reclosable structures bound a second
passageway inside said receptacle when said second and third
reclosable structures are in fully closed states, said receptacle
further comprising a second vent that is in flow communication with
said second interior volume via said second passageway when both
said second vent and said second reclosable structure are in at
least partially open states.
14. The bag as recited in claim 12, wherein said receptacle
comprises first and second walls, said first reclosable structure
comprises first and second closure profiles, said second reclosable
structure comprises third and fourth closure profiles, and said
third reclosable structure comprises fifth and sixth closure
profiles, said first and second closure profiles being mutually
engageable to close said first reclosable structure, said third and
fourth closure profiles being mutually engageable to close said
second reclosable structure, and said fifth and sixth closure
profiles being mutually engageable to close said third reclosable
structure.
15. The bag as recited in claim 14, wherein said first vent
comprises an opening or slit located on said first wall at an
elevation between said second and third reclosable structures.
16. The bag as recited in claim 14, wherein said first and second
walls are joined to each in first and second marginal portions
disposed along a first side edge of said receptacle, said first and
second marginal portions being separated by a gap where said first
and second walls are not joined to each other, respective portions
of said first and second walls at said gap forming said first
vent.
17. The bag as recited in claim 14, wherein said first passageway
has a serpentine shape, a part of a boundary of said first
passageway being formed by a seal, said seal being a zone where
said first and second walls are sealed together.
18. The bag as recited in claim 12, wherein said first reclosable
structure partly opens in response to a first pressure level inside
said first interior volume, and said second reclosable structure
partly opens in response to a second pressure level inside said
second interior volume, said second pressure level being greater
than said first pressure level.
19. A bag comprising a receptacle and first and second reclosable
structures installed inside and across a mouth of said receptacle,
said first and second reclosable structures being parallel and
spaced apart from each other, and at least portions of said first
and second reclosable structures bounding a passageway within said
mouth of said receptacle when said first and second reclosable
structures are in fully closed states, said receptacle comprising a
vent that is in flow communication with an interior volume of said
receptacle via said passageway when both said vent and said first
reclosable structure are in at least partially open states, wherein
if, while said first and second reclosable structures are in fully
closed states, the pressure inside said interior volume is
increased to a first pressure level, said first reclosable
structure will open at least partly to allow gas from said interior
volume to escape into said passageway while said second reclosable
structure remains in a fully closed state.
20. The bag as recited in claim 19, further comprising
compartmentalizing means for dividing said interior volume into
first and second compartments, wherein if the pressure inside one
of said first and second compartments is increased to a second
pressure level less than said first pressure level, said
compartmentalizing means will open at least partly to allow mixing
of the contents of said first and second compartments while said
first reclosable structure remains in a fully closed state.
Description
RELATED PATENT APPLICATION
[0001] This application claims the benefit, under Title 35, United
States Code, .sctn.119(e), of U.S. Provisional Application No.
61/044,541 filed on Apr. 14, 2008.
BACKGROUND
[0002] This invention relates to a flexible bag for use in the
microwaving of cookable items, and more specifically pertains to
the controlled venting of any pressure or steam generated within
the bag during microwaving to assure that such is effectively
released to the atmosphere, preferably without substantially
opening of the structured bag, for maintaining the freshly cooked
and heated texture for the food product, until the bag is
physically opened for consumption or use by the consumer.
[0003] Historically, reclosable bags having press-to-close or
slide-to-close reclosable feature were designed for food storage
applications such as non-refrigerated and refrigerated storage.
These bag products were manufactured from a combination of
polyethylene resins with a reclosable feature. More recently, such
reclosable bag products have been designed for high-temperature
applications; for example, they are microwavable.
[0004] The uses and applications for reclosable bag technology are
continually expanding. There is a need for improvements in
reclosable bags or pouches designed for high-temperature
applications.
BRIEF SUMMARY
[0005] Disclosed herein are flexible storage bags having two
zippers and one or more vents located therebetween. The inner
zipper is designed to open when the pressure inside the bag
increases a sufficient amount during cooking of the bag contents.
When the inner zipper opens, steam from inside the bag can then
escape through the vent or vents while the outer zipper remains
closed. Preferably the bag has a bottom gusset so that it can stand
upright in a microwave oven. When the bag contents are fully
cooked, the bag can be removed from the oven and the outer zipper
can be opened, allowing the user to access the bag contents. If the
user wishes to store any portion of the bag contents not used, the
user can simply close both zippers and then place the resealed bag
inside a refrigerator. The remaining contents of the bag are not
exposed to ambient air via the vent or vents once the inner zipper
has been resealed. The bag can again be placed in a microwave oven
for re-use.
[0006] One aspect of the invention is a bag comprising a receptacle
and first and second reclosable structures installed inside the
receptacle, the first reclosable structure bounding an interior
volume for product inside the receptacle when the first reclosable
structure is in a fully closed state, and at least portions of the
first and second reclosable structures bounding a passageway inside
the receptacle when the first and second reclosable structures are
in fully closed states, the receptacle comprising a vent that is in
flow communication with the interior volume via the passageway when
both the vent and the first reclosable structure are in at least
partially open states, wherein if, while the first and second
reclosable structures are in fully closed states, the pressure
inside the interior volume is increased sufficiently, the first
reclosable structure will open at least partly to allow gas from
the interior volume to escape into the passageway while the second
reclosable structure remains in a fully closed state.
[0007] Another aspect of the invention is a bag comprising a
receptacle and first, second and third reclosable structures
installed inside the receptacle, the first reclosable structure
bounding a first interior volume inside the receptacle when the
first reclosable structure is in a fully closed state, the first
and second reclosable structure bounding a second interior volume
inside the receptacle when the first and second reclosable
structures are in fully closed states, and at least portions of the
second and third reclosable structures bounding a passageway inside
the receptacle when the second and third reclosable structures are
in fully closed states, the receptacle comprising a vent that is in
flow communication with the second interior volume via the
passageway when both the vent and the second reclosable structure
are in at least partially open states, wherein if, while the first
reclosable structure is in a fully closed state, the pressure
inside the first interior volume is increased sufficiently, the
first reclosable structure will open at least partly to allow
mixing of the contents of the first and second interior volumes,
and wherein if, while the first reclosable structure is in a
partially open state and the second and third reclosable structures
are in fully closed states, the pressure inside the interior volume
is further increased sufficiently, the second reclosable structure
will open at least partly to allow gas from the second interior
volume to escape into the passageway while the third reclosable
structure remains in a fully closed state.
[0008] A further aspect of the invention is a bag comprising a
receptacle and first and second reclosable structures installed
inside and across a mouth of the receptacle, the first and second
reclosable structures being parallel and spaced apart from each
other, and at least portions of the first and second reclosable
structures bounding a passageway within the mouth of the receptacle
when the first and second reclosable structures are in fully closed
states, the receptacle comprising a vent that is in flow
communication with an interior volume of the receptacle via the
passageway when both the vent and the first reclosable structure
are in at least partially open states, wherein if, while the first
and second reclosable structures are in fully closed states, the
pressure inside the interior volume is increased suffciently, the
first reclosable structure will open at least partly to allow gas
from the interior volume to escape into the passageway while the
second reclosable structure remains in a fully closed state.
[0009] Other aspects of the invention are disclosed and claimed
below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a drawing showing an isometric view of a vented
reclosable storage bag in accordance with one embodiment.
[0011] FIG. 2 is a drawing showing a plan view of the storage bag
depicted in FIG. 1.
[0012] FIGS. 3-6 are drawings showing sectional view of vented
reclosable storage bags in accordance with alternative
embodiments.
[0013] FIG. 7 is a drawing showing a plan view of a vented
reclosable storage bag having serpentine passageways between a pair
of zippers.
[0014] FIG. 8 is a drawing showing a plan view of a vented
reclosable storage bag having multiple product compartments.
[0015] Reference will hereinafter be made to the drawings in which
similar elements in different drawings bear the same reference
numerals.
DETAILED DESCRIPTION
[0016] The vented reclosable storage bags disclosed herein are
designed to withstand the particular temperature and pressure
conditions attending microwave cooking. Each reclosable bag is made
of flexible material, such as polypropylene, plastic lamination
films or other high-melting-temperature flexible material. Each
reclosable bag has a pair of reclosable structures, e.g., a pair of
plastic zippers, each zipper comprising a pair of zipper strips
having mutually interlockable closure profiles. The reclosable
structures may be arranged in mutually parallel and spaced-apart
relationship with at least one passageway therebetween. Also each
reclosable bag has one or more vents for pressure relief. The vents
are located between the reclosable structures, preferably at or
near the side edges of the storage bag. Each vent may take the form
of a slit or a small opening. The vent can also be made to be
forced open during initial exposure to pressure. Optionally, the
storage bag may be constructed with a bottom gusset that enables
the bag to stand upright inside a microwave oven. For each
embodiment disclosed hereinafter, the plastic film used to
construct the bag may be thin for single-use bags or thick for
multiple-use bags.
[0017] The inner reclosable structure is designed to partially open
when the pressure inside the bag increases sufficiently (e.g., to a
pressure in the range greater than 1 and less than 4 pounds per
square inch) during cooking. For example, the bag and its contents
may be placed inside a microwave oven, which oven is then set to
cook the bag contents. During this process, the pressure buildup
inside the bag is relieved by the partial opening of the inner
reclosable structure and the release of steam through the one or
more vents formed in the reclosable bag. The pressure relief
prevents the bag from bursting or otherwise having its integrity
compromised. The outer reclosable structure remains closed during
cooking. After cooking, the outer reclosable structure can be
opened and a desired portion of the cooked contents can be removed
by the consumer. After cooling, the inner reclosable structure can
be resealed and the cooked contents that remain inside the intact
bag can be stored for future use without the need to transfer the
remaining bag contents to some other airtight container.
[0018] FIG. 1 depicts one embodiment of a high-temperature vented
reclosable storage bag suitable for use in cooking food. The bag
shown in FIG. 1 comprises a receptacle 2 made of flexible material,
such as polypropylene film, plastic lamination film, other
higher-melting-temperature material, or a combination of two or
more of the foregoing types of flexible material. A web of flexible
high-temperature is folded and then heat sealed (or ultrasonically
welded) in marginal regions adjacent the side edges to form a front
panel 4, a rear panel 6 and a bottom gusset 8. The receptacle 2 has
an interior volume (not shown) for food product and a mouth in
which inner and outer reclosable plastic zippers 10 and 12 are
installed. The top and bottom edges of the receptacle are indicated
by reference numerals 14 and 16 respectively in FIG. 1. In this
embodiment, each zipper comprises a string (i.e., flangeless)
zipper consisting of two zipper strips having mutually
interlockable closure profiles respectively. These zipper strips
are joined to the bag walls by heat sealing or ultrasonic welding
and extend across the mouth of the receptacle. Preferably they are
mutually parallel and spaced apart. The upper portions of the front
and rear panels of the receptacle are provided with respective
pluralities of mutually parallel gripping ribs 18 (the ribs on the
rear panel are not visible in FIG. 1) which facilitate gripping of
those upper portions during opening of the outer zipper 10 by the
user.
[0019] The space between the zippers 10 and 12 may include a
passageway 11 that allows flow communication between a pair of
vents 20 and 20' respectively located at the side edges of the bag.
More specifically, that passageway is bounded by the zippers 10 and
12 and by those confronting portions of the front and rear panels 4
and 6 that extend between the zippers 10 and 12. The vent 20 is
formed by confronting marginal portions of the front and rear
panels 4 and 6 that are disposed adjacent the left-hand side edge
of the receptacle 2; the vent 20' is formed by confronting marginal
portions of the front and rear panels 4 and 6 that are disposed
adjacent the right-hand side edge of the receptacle 2. The vents 20
and 20' may be closed until such time that the inner zipper 12
partially opens, allowing steam to flow into the passageway 11 and
then out through the vents. Alternatively, the vents 20 and 20' may
already be open prior to the escape of steam into the
passageway.
[0020] FIG. 2 shows a plan view of the storage bag depicted in FIG.
1. The side seals 22 and 24 are indicated by hatching. Above the
horizontal dashed line (which indicates the bottom gusset 8),
respective confronting marginal portions of the front and rear
panels of the receptacle are sealed together except where the ends
of the zippers 10 and 12 intervene and where the vents 20 and 20'
are located. As shown, vents 20 and 20' are formed by confronting
marginal portions of the front and rear panels of the receptacle
that are not sealed together. The vents can be formed by providing
gaps in the heated side sealing bars typically used to form side
seals 22 and 24. The ends of the zippers 10 and 12 are also joined
together in the side seals 22 and 24, with the adjoining marginal
portions of the front and rear panels being joined to the fused
zipper ends. Below the horizontal dashed line (8), respective
marginal portions of the front panel and rear panels of the
receptacle and intervening marginal portions of the two gusset
panels are all sealed together in the side seals 22 and 24.
[0021] FIG. 2 shows a vented reclosable storage that is empty and
flat. A person skilled in the art will appreciate that when the
central portion of the bottom gusset 8 is unfolded and the
receptacle is filled with food product, the portions of the bottom
edges of the front and rear panels disposed between the side seals
22 and 24 will move apart and, in combination with the unfolded
portion of the bottom gusset, will form a base that enables the
filled bag to stand upright during cooking.
[0022] FIG. 3 is a sectional view of a vented reclosable storage
bag having a bottom gusset in accordance with an alternative
embodiment. The bottom gusset 8 comprises two gusset panels 26 and
28 formed by folding a web. As previously described, in the side
seal regions the marginal portions of the gusset panels 26 and 28
and the front and rear panels 4 and 6 of the receptacle are all
joined together by heat sealing. The embodiment shown in FIG. 3
includes three zippers. The outer zipper comprises a female element
30 and a double hook element 32 that interlocks with the female
element 30 in a conventional manner to form a closure. The
intermediate zipper comprises a female element 34 and a monohook
element 36 that interlocks with the female element 34 in a
conventional manner to form a closure. The inner zipper comprises a
female element 38 and a monohook element 40 that interlocks with
the female element 38 in a conventional manner to form a closure.
The passageway 11 is disposed between the female elements 34 and
38. In this embodiment, a vent 42 is formed in the front panel 4
and a vent 42' is formed in the rear panel 6. Each of these vents
may be a slit or an opening. The vents 42 and 42' allow the escape
of steam from the interior volume of the receptacle when the inner
zipper is partially open (not shown), which steam flows through the
opening in the inner zipper, into the passageway 11, and then out
the vents 42 and 42'. Alternatively, the person skilled in the art
will readily understand that the vents can be placed at the side
edges in the manner previously described with reference to FIG.
1.
[0023] FIG. 4 is a sectional view of a vented reclosable storage
bag in accordance with a further embodiment. In this embodiment the
receptacle is shown as not having a bottom gusset, but a person
skilled in the art will readily appreciate that a bottom gusset
could be provided. The embodiment shown in FIG. 4 includes two
zippers. The outer zipper comprises a female element 44 and a
double hook element 46 that interlocks with the female element 44
in a conventional manner to form a closure. The inner zipper
comprises a female element 48 and a double hook element 50 that
interlocks with the female element 48 in a conventional manner to
form a closure. The passageway 11 is disposed between the female
elements 44 and 48. In this embodiment, a vent 42 is formed in the
front panel 4 and a vent 42' is formed in the rear panel 6. Each of
these vents may be a slit or an opening. As previously described,
the vents 42 and 42' allow the escape of steam from the interior
volume of the receptacle when the inner zipper is partially open
(not shown), which steam flows through the opening in the inner
zipper, into the passageway 11, and then out the vents 42 and 42'.
Alternatively, the vents can be placed at the side edges in the
manner previously described with reference to FIG. 1.
[0024] FIG. 5 is a sectional view of a vented reclosable storage
bag in accordance with yet another embodiment. Again the receptacle
is shown as not having a bottom gusset, but optionally a bottom
gusset could be provided. The embodiment shown in FIG. 4 includes
two zippers. The outer zipper comprises a female element 44 and a
double hook element 46 that interlocks with the female element 44
in a conventional manner to form a closure. The inner zipper
comprises a female element 52 having a detent 78, a double hook
element 54 that interlocks with the female element 52, and a backup
element 56. The detent 78 bears against the backup element 56 when
the female element 52 starts to open, thereby providing a
resistance to opening. The passageway 11 is disposed between the
female element 44 and the backup element 56. In this embodiment, a
vent 42 is formed in the front panel 4 and a vent 42' is formed in
the rear panel 6. Each of these vents may be a slit or an opening.
As previously described, the vents 42 and 42' allow the escape of
steam from the interior volume of the receptacle when the inner
zipper is partially open (not shown), which steam flows through the
opening in the inner zipper, into the passageway 11, and then out
the vents 42 and 42'. Alternatively, the vents can be placed at the
side edges in the manner previously described with reference to
FIG. 1.
[0025] FIG. 6 is a sectional view of a vented reclosable storage
bag in accordance with yet another embodiment. This embodiment is
similar to the embodiment shown in FIG. 4, with the difference that
instead of two string zippers, a double zipper with common base
strips 74 and 76 is installed in the mouth of the receptacle. The
outer zipper comprises a female element 44 and a double hook
element 46 that interlocks with the female element 44 in a
conventional manner to form a closure. The inner zipper comprises a
female element 48 and a double hook element 50 that interlocks with
the female element 48 in a conventional manner to form a closure.
The passageway 11 is disposed between the female elements 44 and 48
and between the common base strips 74 and 76. In this embodiment, a
vent 42 is formed in the joined portions of the front panel 4 and
common base strip 74, and a vent 42' is formed in the joined
portions of the rear panel 6 and common base strip 76. Each of
these vents may be a slit or an opening. Alternatively, the vents
can be formed by confronting marginal portions of the common base
strips (i.e., marginal portions disposed between the closure
profiles) that are not sealed together in the side seal
regions.
[0026] A vented reclosable storage bag in accordance with a further
embodiment is shown in FIG. 7. The zippers 10 and 12 are mutually
parallel and spaced apart to form a passageway 11 that communicates
with a pair of vents 20 and 20' located between the zippers and at
the side edges. The distance between the zippers can be varied to
allow precise control of steam vent size and the rate at which
steam can escape from the bag. In the example depicted in FIG. 7,
means are provided to direct the flow of steam along serpentine
paths 64 and 70 before exiting via the vents 20 and 20', thereby
better controlling the pressure inside the receptacle 2. The
serpentine path 64 is formed by heat sealing the front and rear
panels together in rectangular areas 60 and 62; the serpentine path
70 is formed by heat sealing the front and rear panels together in
rectangular areas 66 and 68. When the pressure inside the
receptacle 2 increases to a sufficient level, a central portion of
the inner zipper 12 will open, allowing steam to escape into
passageway 11. The pressure differential between the inside and
outside of the bag will cause some steam to flow toward vent 20 via
serpentine path 64 and other steam to flow toward vent 20' via
serpentine path 70.
[0027] With respect to all embodiments disclosed above, a person
skilled in the art will appreciate that the broad scope of the
invention includes reclosable storage bags having only one vent as
well as bags having two or more vents disposed between the inner
and outer zippers.
[0028] In accordance with further embodiments of the invention, a
vented reclosable storage bag may be provided with multiple
compartments that open at different times during cooking based on
what is in each compartment, the zipper designs, and the
compartment sizes. For example, one could have a little water and
brown sugar in a top compartment and carrots in a bottom
compartment. A reclosable bag having a bottom compartment 80 and a
top compartment 82 is shown in FIG. 8. The top and bottom
compartments are separated by a seal 72 that opens when a first
pressure level in the top or bottom compartment is reached. Seal 72
may be a reclosable structure such as a plastic zipper. The top
compartment has a plastic zipper 12 that opens when a second
pressure level is reached, the second pressure level being higher
than the first pressure level. In this example, the seal 72 between
the top and bottom compartments would open first, allowing the
water and brown sugar in the top compartment 82 to fall into the
bottom compartment 80 and be mixed with the carrots during cooking.
As the temperature inside the bag rises further, the internal
pressure increases until the second pressure level is reached, at
which time the zipper 12 would partially open, allowing steam from
the top compartment 82 to escape into the passageway 11 and then
out vents 20 and 20 in the manner previously described.
[0029] While the invention has been described with reference to
preferred embodiments, it will be understood by those skilled in
the art that various changes may be made and equivalents may be
substituted for members thereof without departing from the scope of
the invention. In addition, many modifications may be made to adapt
a particular situation to the teachings of the invention without
departing from the essential scope thereof. Therefore it is
intended that the invention not be limited to the particular
embodiment disclosed as the best mode contemplated for carrying out
this invention, but that the invention will include all embodiments
falling within the scope of the appended claims.
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