U.S. patent application number 11/627909 was filed with the patent office on 2007-07-26 for polymeric package with resealable closure and valve and methods relating thereto.
This patent application is currently assigned to Alcoa Inc.. Invention is credited to James E. Buchman.
Application Number | 20070172157 11/627909 |
Document ID | / |
Family ID | 39407343 |
Filed Date | 2007-07-26 |
United States Patent
Application |
20070172157 |
Kind Code |
A1 |
Buchman; James E. |
July 26, 2007 |
POLYMERIC PACKAGE WITH RESEALABLE CLOSURE AND VALVE AND METHODS
RELATING THERETO
Abstract
The present invention provides a vacuum storage bag system
having a storage device having at least one polymeric sheet sealed
along a portion of its' periphery to provide an opening to a
storage space; a resealable closure structure adapted to seal the
opening to the storage space, the resealable closure structure
comprising selectively engaging male and female profiles and a
sealing compound comprising liquid silicone and at least one filler
in proportions suitable for at least incidental contact to food
items contained within the storage space; a vacuum valve assembly
disposed on the polymeric sheet; a stand-off structure disposed
adjacent to the vacuum valve assembly, wherein the stand-off
structure has a series of raised surfaces facing the vacuum valve
assembly; a portable vacuum pump assembly structured to engage the
vacuum valve assembly; and a liquid separator assembly coupled to
the portable vacuum pump assembly.
Inventors: |
Buchman; James E.;
(Hortonville, WI) |
Correspondence
Address: |
INTELLECTUAL PROPERTY
ALCOA TECHNICAL CENTER, BUILDING C
100 TECHNICAL DRIVE
ALCOA CENTER
PA
15069-0001
US
|
Assignee: |
Alcoa Inc.
Pittsburgh
PA
|
Family ID: |
39407343 |
Appl. No.: |
11/627909 |
Filed: |
January 26, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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11186131 |
Jul 20, 2005 |
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11627909 |
Jan 26, 2007 |
|
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60590858 |
Jul 23, 2004 |
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60602685 |
Aug 19, 2004 |
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60609920 |
Sep 15, 2004 |
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Current U.S.
Class: |
383/63 ; 383/103;
383/105 |
Current CPC
Class: |
B65D 81/2038 20130101;
B65B 31/04 20130101; B65D 33/2508 20130101; B65D 33/2591 20130101;
B65D 81/2023 20130101; B65D 81/261 20130101; B65D 33/2541
20130101 |
Class at
Publication: |
383/063 ;
383/103; 383/105 |
International
Class: |
B65D 33/16 20060101
B65D033/16; B65D 33/01 20060101 B65D033/01; B65D 33/00 20060101
B65D033/00 |
Claims
1. A vacuum storage bag comprising: an evacuable package comprising
at least one polymeric sheet sealed about a portion of its
periphery to define a first panel, a second panel, an opening and
an interior space; a vacuum valve in fluid communication with the
interior space of the evacuable package; and a resealable closure
interconnected to the evacuable package proximal the opening of the
evacuable package, the resealable closure comprising: a first
flexible flange interconnected to the first panel of the evacuable
package, the first flexible flange comprising a first interengaging
profile; and a second flexible flange interconnected to the second
panel of the evacuable package, opposite the first flexible flange,
the second flexible flange comprising: a top portion comprising a
second interengaging profile adapted to restrictively engage the
first interengaging profile; and a skirt portion interconnected
with the top portion, the skirt portion comprising a stand-off
structure.
2. The storage bag of claim 1, wherein the vacuum valve is
interconnected to the skirt portion of the second flexible
flange.
3. The storage bag of claim 1, wherein vacuum valve is integral
with the skirt portion of the second flexible flange.
4. The storage bag of claim 1, wherein the top portion of the
second flexible flange comprises LDPE and the skirt portion
comprises MDPE.
5. The storage bag of claim 1, wherein the top portion comprises a
thickness of not greater than about 3 mils, and wherein the skirt
portion comprises a thickness of at least about 10 mils.
6. The storage bag of claim 1, wherein the ratio of the thickness
of the skirt portion to the thickness of the top portion is at
least about 1.5:1.
7. The storage bag of claim 1, wherein the skirt portion further
comprises: a non-textured portion adjacent a lateral edge of the
stand-off structure.
8. The storage bag of claim 1, wherein the stand-off structure is
an embossed structure.
9. A method for forming the resealable closure of claim 1, the
method comprising: feeding at least a portion of the resealable
closure through an anvil roll and an embossing wheel; and
contacting at least some of the skirt portion of the resealable
closure with an embossing portion of the embossing roll.
10. The method of claim 9, further comprising: contacting the skirt
portion of the resealable closure with a non-embossed portion of
the embossing roll.
11. A vacuum storage bag comprising: an evacuable package defining
an interior space, the evacuable package having a first side panel
and an opposing second side panel; a vacuum valve in fluid
communication with the interior space of the evacuable package; and
a wicking material in fluid communication with the interior space
of the evacuable package.
12. The vacuum storage bag of claim 11, wherein the wicking
material is interconnected to at least one of the first side panel
and the second side panel of the evacuable package.
13. The vacuum storage bag of claim 12, wherein the wicking
material is adhesively bonded to at least one of the first and
second sides panels of the evacuable package.
14. The vacuum storage bag of claim 11, further comprising: a
plurality of barriers proximal the periphery of the wicking
material and surrounding at least a portion of the wicking
material, the plurality of barriers defining a wicking section of
the evacuable package and restricting movement of the wicking
material from the wicking section.
15. The vacuum storage bag of claim 14, wherein the plurality of
barriers at least assist in defining at least one channel, the at
least one channel facilitating liquid communication between the
interior space of the evacuable package and the wicking
material.
16. The vacuum storage bag of claim 11, wherein the wicking
material comprises a cellulosed-based material.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent
application Ser. No. 11/186,131 filed Jul. 20, 2005, which claims
priority under 35 U.S.C. .sctn. 119(e) to U.S. Provisional Patent
Application Nos., 60/590,858, filed on Jul. 23, 2004, 60/602,685
filed on Aug. 19, 2004, and 60/609,920, filed on Sep. 15, 2004.
Each of the above patent applications is incorporated herein by
reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to a flexible, inexpensive,
evacuable storage device optionally having a resealable opening and
a caulking composition. The present invention also relates to a
vacuum storage device and a system for vacuum storage.
BACKGROUND OF THE INVENTION
[0003] Flexible, sealable storage devices, such as consumer storage
bags are commonly used to store items such as, but not limited to,
food. These devices typically have a bag body made from a thin,
flexible plastic material and include a resealable closure. While
inexpensive and easy to use, these devices also allow a quantity of
air to be enclosed with the item being stored. Air within a storage
device containing food is not desirable as the air reacts with the
food and will cause spoliation. Additionally, when storage bags are
placed in a below freezing environment, typically in a freezer,
"freezer burn" may also damage the food items. Freezer burn occurs
when moisture is drawn from the food item and forms ice, typically
on the food item. Freezer burn is reduced when entrapped air is
substantially eliminated from the storage device with concomitant
contouring of the bag wall of the storage device around the food
item. Consequently, less moisture will be drawn out of the food
item.
[0004] Prior systems that evacuate flexible storage bags typically
include a large device having a vacuum unit and a heat sealer
structured to bond sheets of plastic together. The user typically
cuts a length of plastic from a roll of plastic and uses the heat
sealer to form the plastic into a bag with an opening. After an
item has been placed in the bag through the opening, the vacuum
unit is then used to remove substantially all of the air from the
bag and the bag is sealed. Such systems have various disadvantages,
including high materials costs due to once-use methodology and
rigorous sealing requirements.
SUMMARY OF THE INVENTION
[0005] In view of the foregoing background, there is need for a
vacuum storage system utilizing a portable vacuum device and
optionally a resealable, evacuable, flexible storage device.
Resealable closure systems are known, for example, interlocking
profiles used in plastic bags. However, in a typical resealable
closure, engagement of the sealing structures is rarely perfect,
leaving gaps in the profile seal. Moreover, during manufacture of
reclosable devices, frequently seals at the ends of the reclosable
device distort the engaging portions of the closure which can also
provide an unsealed region in the closure. As a consequence of
these and other problems associated with resealable closures, a bag
utilizing a resealable closure may not be air tight. Consequently
when a bag utilizing a resealable closure is subjected to a
pressure differential, for example, when it is evacuated or when
there is a partial pressure differential of a particular gas
between the inside and outside of the bag, gas can leak across the
resealable closure and enter, or leave the sealed package through
the closure. Thus, gases, for example, air may penetrate into a
sealed bag, or for example water vapor may leak from a sealed bag.
This is especially a problem when the interior of the bag is at a
different pressure than the ambient air, for example, when the bag
is under a vacuum, or when the bag contains a gas at a higher or
lower partial pressure than the gas is present in the ambient.
[0006] Accordingly, there is a need for a flexible, resealable
storage device wherein the sealing structure has a resistance to
fluid permeability under a pressure differential across the sealing
device. Moreover, there is a need for a pre-made, inexpensive,
flexible, reusable storage device having a valve structured to
operate with a portable vacuum pump. Additionally, there is a
further need for a resealable closure that provides for reduction
in entrapped air, a flexible bag wall to maintain item conformance,
and an air tight seal providing reduced permeability to oxygen,
atmosphere intrusion or transmission, bacteria, molds and/or other
sources of contamination when used in combination with vacuum pump
technology. There is also a need for vacuum pump technology which
provides for portability and utility in evacuating a food storage
flexible package.
[0007] These needs, and others, are met by the present invention
that provides in one aspect a vacuum system comprising: (a) a
vacuum pump having a suction side; (b) a vacuum conduit in fluid
communication with said vacuum pump suction side, the vacuum
conduit comprising: (i) a gas/liquid separator means; (ii) at least
one vacuum valve optionally comprising a caulking compound (also
termed herein a caulking composition) disposed therein; (iii)
optionally, a standoff structure; (iv) optionally one or more
quick-connect means; (c) an evacuable package defining an interior
space in fluid communication with said vacuum conduit; and (d)
optionally, a resealable closure defining an opening of said
evacuable package. In some preferred embodiments the vacuum pump is
portable.
[0008] In one embodiment, the vacuum system comprises a kit
containing in one assembly the vacuum pump, a liquid separator
means and a portion of the vacuum conduit terminated with one
portion of a quick-connect means, and in a second assembly, an
additional portion of the vacuum conduit comprising a cooperating
portion of the quick-connect means, a vacuum valve, an evacuable
package and optionally a stand-off structure. In some preferred
embodiments, the vacuum pump assembly is provided in a break-apart
form wherein one portion of the system comprises the vacuum pump
integrally assembled with some portions of the vacuum conduit, for
example, the liquid/gas separator, terminating in a quick-connect
means, and the remaining portions of the vacuum conduit are
provided integral with the evacuable storage package, for example,
a vacuum valve having a cooperating quick-connect means arranged in
the remaining portion of the vacuum conduit and integral with the
flexible package and optionally a stand-off structure.
[0009] In one embodiment the standoff structure comprises an
embossed plastic sheet having a channel side and a projection side.
In one embodiment the standoff structure is positioned within the
evacuable package having the channel side in fluid communication
with the vacuum conduit and vacuum valve, and having the projection
side proximal to the interior space defined by the package.
[0010] In another aspect, the present invention provides an
evacuable storage package defining an interior space, a vacuum
valve in fluid communication therewith, optionally a standoff
structure in fluid communication with the vacuum valve, and
optionally a resealable closure defining an opening into the
interior space of the package wherein the resealable closure
comprises at least one set of interengaging profiles.
[0011] In some embodiments the resealable closure defining the
opening of the inventive storage package comprises at least one
pair of opposed interengaging profiles wherein at least one of said
interengaging profiles has associated therewith a portion of the
closure comprising a low density sealing material, thus providing a
region in the closure having a high degree of conformance with the
associated interengaging portion of the closure and as well as
insuring that when the closure is end-sealed, a gap free seal is
provided. In some embodiments the sealing material comprises a
portion of one or both interengaging profiles. In some embodiments
the sealing material comprises a portion of the flange or of a post
of the closure. In some embodiments the sealing material comprises
the entire length of the profiles. In some embodiments the sealing
material comprises selected portions of the profiles, such as the
periphery portions of one or both of the interengaging profiles. In
some embodiments the portion of the closure comprising the sealing
material is made from a polyolefin material having a density of not
more than 0.925 g/cm.sup.3, as defined according to ASTM D1505-03,
entitled "The standard test method for density of plastics by
density gradient techniques", Book of Standards Volume 08.01
(2005). In some embodiments the resealable closure is used in
conjunction with a caulking composition. In one embodiment of the
present invention, the caulking composition acts to fill one or
more voids between the interengaging profiles, thus reducing the
infiltration of ambient into the storage device when it is sealed
and placed in a condition of reduced pressure.
[0012] In some embodiments the caulking composition is disposed
proximal to the interengaging closure profiles such that it is
infiltrated into any gaps existing in the closure when the closure
profiles are engaged.
[0013] In some embodiments the caulking composition comprises a
mixture suitable for at least incidental contact to food items. In
some embodiments the caulking composition maintains chemical
stability throughout a temperature range suitable for food storage
and packaging.
[0014] In one embodiment the caulking composition is positioned on
the first male profile and/or the first female profile. In one
embodiment the caulking composition is placed proximal to the
interengaging profiles of the closure in one or more positions that
permit it to infiltrate gaps formed in the seal formed by the
interengaged profiles, for example, as applied to the ends of the
closure near the crush area, and as a continuous bead along the
closure either on or between one or more of the interengaging
profile portions.
[0015] In another embodiment of the present invention, the
resealable closure device further comprises at least a second set
of interengaging profiles positioned in close proximity and
parallel to the first set of interengaging profiles. In one
embodiment having multiple pairs of interengaging profiles, in
addition to sealing material being positioned between each of the
engaged portions of the interengaging profiles, a bead of caulking
composition may be positioned within the space separating the
substantially parallel sets of interengaging profiles.
[0016] In one embodiment, the caulking composition comprises
constituents such that it maintains integrity, without
decomposition, throughout a temperature range suitable for
packaging and food storage. Temperatures suitable for packaging and
food storage typically range from approximately -10.degree. F. to
approximately +160.degree. F. In one embodiment the caulking
composition comprises liquid silicone and a filler, e.g. fumed
silica, in proportions to provide a grease with a grease
consistency number of approximately 2.0, as characterized by
National Lubricating Grease Institute (NGLI) standards. In one
embodiment, the caulking composition comprises a soy adhesive, such
as Pro-cote.RTM. soy polymer available from DuPont.TM.. In another
embodiment, the caulking composition comprises soy oils, for
example, those available from Cargill.TM.. Industrial Oils &
Lubricants. In one embodiment the caulking composition comprises
two reactive constituents, each residing on a different portion of
the closure, such that when the interengaging profiles of the
closure are engaged the two constituents are admixed, providing a
reaction product which infiltrates at least one void defined by the
interengaging closure profiles.
[0017] In one aspect, a vacuum storage bag is provided, the vacuum
storage bag including an evacuable package, a vacuum valve integral
with the evacuable package, and a plurality of barriers positioned
within the evacuable package. The evacuable package comprises at
least one polymeric sheet sealed about a portion of its periphery
defining first and second panels, an opening and an interior space.
Each of the plurality of barriers interconnects a portion of the
first panel of the evacuable package to a portion of the second
panel of the evacuable package. The plurality of barriers also at
least assist in defining at least one channel, which is in fluid
communication with the vacuum valve and the interior space of the
evacuable package.
[0018] The plurality of barriers may be of various configurations.
For example, the plurality of barriers may be intermittently
located about at least a portion of the periphery of the vacuum
valve. In one approach, the vacuum valve is integral with the first
panel and the plurality of barriers are intermittently located
about at least a portion of the periphery of the vacuum valve. The
plurality of barriers may be arranged such that the plurality of
barriers define various portions of shapes, such as at least a
portion of an ellipse. The plurality of barriers may be
interconnected with the evacuable package in any suitable manner.
For example, the plurality of barriers may be integral with both
the first and second panels of the evacuable package, such as via
heat sealing of the first panel to the second panel. Thus, in this
embodiment, each of the plurality of barriers may define an
uninterrupted span from the first panel to the second panel. In
another embodiment, the plurality of barriers may comprise a
polymeric material bonded to the interior space of the evacuable
package.
[0019] In one approach, the plurality of barriers are located
proximal at least a portion of the perimeter of the evacuable
package. In a particular embodiment, a first portion of the
plurality of barriers may be substantially parallel to a lateral
side of the evacuable package. In turn, a second portion of the
plurality of barriers may be substantially orthogonal to the same
lateral side of the evacuable package. In one embodiment, the first
portion of the barriers may be interconnected to the second portion
of barriers, such as when it is desired to define a corner channel
portion of the evacuable package.
[0020] In a particular embodiment, the plurality of barriers may
define a sealing line, and the sealing line may be transverse to a
lateral side of the evacuable package. In one embodiment, the
sealing line is visible from the exterior of the evacuable package
and facilitates visual confirmation of a fill level for the
evacuable package. In a related embodiment, a visual indicator
(e.g., color or text) may be co-located with the sealing line and
this visual indicator may facilitate visual confirmation of a fill
level for the vacuum storage.
[0021] The plurality of barriers may be utilized in conjunction
with various other components of the vacuum storage bag. In one
approach, the storage bag may include a standoff structure
positioned within the evacuable package. In one embodiment, the
stand-off structure may be located proximal the plurality of
barriers. In a particular embodiment, at least some of the
plurality of barriers may overlap with the stand-off structure.
That is, the plurality of barriers and stand-off structure may be
co-located at various portions of the evacuable package. In a
particular approach, at least one channel fluidly interconnects the
stand-off structure and the vacuum valve, such when the plurality
of barriers and/or the geometrical structures of the stand-off
structure define the channel.
[0022] In one approach, the evacuable package may include a
resealable closure comprising at least one set of interengaging
profiles that facilitate repeated opening and closing of the
evacuable package. This resealable closure may define the opening
of the evacuable package. In a particular embodiment, the plurality
of barriers may be located between the resealable closure and the
vacuum valve. In a related approach, the storage bag may include a
grease composition associated with the resealable closure. This
grease composition may be positioned on the resealable closure to
facilitate sealing of the evacuable package.
[0023] In another aspect, the vacuum storage bag may include
materials to facilitate wicking of liquids contained therein. In
one approach, the vacuum storage bag includes a wicking material in
fluid communication with the interior space of the evacuable
package. In one embodiment, this wicking material may be
interconnected to at least one of the first panel and second panel
of the evacuable package. For example, the wicking material may be
adhesively bonded to at least one of the first panel and second
panel of the evacuable package. In another embodiment, to restrict
movement of the wicking material within the evacuable package, a
plurality of barriers, such as those described above, may be
utilized. In one embodiment, the vacuum storage bag includes a
plurality of barriers proximal the periphery of the wicking
material and surrounding at least a portion of the wicking
material. In this embodiment, the plurality of barriers may define
a wicking section of the evacuable package and restrict movement of
the wicking material from this wicking section. As described above,
the plurality of barriers may at least assist in defining at least
one channel, this at least one channel being adapted to facilitate
liquid communication between the interior space of the evacuable
package and the wicking material. The wicking material may be any
suitable material adapted to adsorb or absorb liquids, such as
desiccants, cellulose-based materials, and others.
[0024] As noted above, the resealable closure generally facilitates
repeated opening and closing of the evacuable package. The
resealable closure may also include structures to facilitate
removal of air from the evacuable package. In one aspect, the
resealable closure may include a first flexible flange
interconnected to the first panel of the evacuable package, the
first flexible flange including a first interengaging profile. The
resealable closure may further include a second flexible flange
interconnected to the second panel of the evacuable package and
opposite the first flexible flange. The second flexible flange may
include a top portion and a skirt portion, the skirt portion being
interconnected to/integral with the top portion. The top portion of
the second flexible flange may include a second interengaging
profile adapted to restrictably engage the first interengaging
profile. The skirt portion of the second flexible flange may
include one or more structures for facilitating removal of gases
from the evacuable package. In one embodiment, the skirt portion
may include a stand-off structure (e.g., an embossed structure).
Thus, gases proximal the resealable closure may be more readily
removed from the evacuable package via the channels of the skirt
portion stand-off structure.
[0025] In another embodiment, the skirt portion may include a
vacuum valve interconnected therewith. In this regard, the vacuum
valve may be integral with the skirt portion of the second flexible
flange. To facilitate attachment of the vacuum valve, the skirt
portion of the second flexible flange may include differing
materials and/or thicknesses relative to the top portion of the
second flexible flange. For example, the top portion of the second
flexible flange may include low density polyethylene (LDPE) and the
skirt portion may include medium density polyethylene (MDPE). In a
related approach, the top portion of the second flexible flange may
include a first thickness and the skirt portion may include a
second thickness that is greater than the first thickness. In a
particular embodiment, the top portion comprises a thickness of not
greater than about 3 mil, and the skirt portion of the second
flexible flange comprises a thickness of at least about 10 mils. In
another related approach, the ratio of the thickness of the skirt
portion to the thickness of the top portion may be tailored to
facilitate interconnection of structures to the skirt portion of
the second flexible flange while restricting the thickness of the
top portion. For example, the ratio of the thickness of the skirt
portion to the thickness of the top portion may be at least about
1.5:1.
[0026] The skirt portion may also include non-structured portions.
For example, the skirt portion may include non-textural portions
adjacent a lateral edge of the skirt portion. These non-textured
portions may facilitate sealing of the evacuable package about the
periphery.
[0027] Methods for forming resealable closures comprising
structures are also provided. In one approach, the method includes
the step of feeding at least a portion of the resealable closure
through an anvil and an embossing wheel, and contacting at least
some of the skirt portion of the resealable closure with an
embossing portion of an embossing roll. The embossing roll may
include structures that facilitate development of the stand-off
structure (e.g., protrusions and/or cavities). The method may also
include the step of contacting the skirt portion of the resealable
closure with a non-embossed portion of the embossing roll to
facilitate production of non-embossed portions of the skirt portion
of the resealable closure.
[0028] As may be appreciated, various aspects, approaches and/or
embodiments noted hereinabove may be combined to yield various
different configurations of the vacuum storage system and
corresponding methods. These and other aspects, advantages, and
novel features of the invention are set forth in part in the
description that follows and will become apparent to those skilled
in the art upon examination of the following description and
figures, or may be learned by practicing the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1a is a front view of one of embodiment of a storage
device.
[0030] FIG. 1b is a side, cross-sectional view of one embodiment of
a storage device.
[0031] FIGS. 2-7 are cross-sectional views of embodiments of
resealable closure devices including a caulking composition and/or
sealing material.
[0032] FIG. 8 (perspective view) depicts one embodiment of a
clamping means.
[0033] FIG. 9 is an exploded view of one embodiment of a vacuum
valve assembly.
[0034] FIGS. 10a-10c are front views of embodiments of stand-off
structures.
[0035] FIGS. 11a-11c are isometric views of embodiments of
stand-off structures.
[0036] FIGS. 12a-12b are cross-sectional views of embodiments of
stand-off structures.
[0037] FIGS. 13a-13d are isometric views of embodiments of a
storage device in an unfolded condition.
[0038] FIG. 14 is an isometric view of one embodiment of a storage
device in a folded condition.
[0039] FIG. 15 is a cross-sectional view of the storage device
depicted in FIG. 14 along section line 9-9.
[0040] FIGS. 16a-16b illustrate the front view of one embodiment of
a closing clip and the side view of the closing clip.
[0041] FIG. 17 is a side view of one embodiment of an end stop.
[0042] FIG. 18(a) is an isometric view of one embodiment of a
suction cup tip of a portable vacuum pump
[0043] FIG. 18(b) depicts a side cross-sectional view of the
suction cup tip depicted in FIG. 18(a).
[0044] FIG. 19 is an exploded, cross-sectional view of one
embodiment of a liquid separator.
[0045] FIG. 20 is an exploded, isometric view of one embodiment of
a liquid separator.
[0046] FIG. 21 is an isometric view of one embodiment of an
evacuable bag in use, wherein the bag includes a stand-off
structure and vacuum valve assembly.
[0047] FIGS. 22a-22d illustrate various embodiments of an evacuable
package having a barrier structure.
[0048] FIG. 23 is a perspective view of one embodiment of an
evacuable package having a vacuum valve assembly interconnected
with a resealable closure.
[0049] FIG. 24 is a perspective view of an evacuable package having
a resealable closure that includes a stand-off structure.
[0050] FIGS. 25a-25c illustrate various views of one embodiment of
a resealable closure including a stand-off structure and an
interconnected vacuum valve assembly.
[0051] FIG. 26 is a perspective view of one embodiment of a process
for producing a resealable closure having a stand-off
structure.
[0052] FIG. 27a is a perspective view of one embodiment of a
process for producing a resealable closure having a vacuum valve
interconnected therewith.
[0053] FIG. 27b is a perspective view of one embodiment of a
process for producing a plurality of resealable closures, each
having a vacuum valve interconnected therewith.
[0054] FIG. 28 illustrates one embodiment of an evacuable package
including a wicking material.
DETAILED DESCRIPTION
[0055] The present invention is now discussed in more detail
referring to the drawings that accompany the present application.
In the accompanying drawings, like and/or corresponding elements
are referred to by like reference numbers. In one embodiment of the
present invention, a vacuum system is provided that may include a
portable vacuum pump and an evacuable package in communication
through a vacuum conduit. The evacuable package may optionally
include a stand-off structure and a resealable closure having a
caulking composition disposed thereon. In one embodiment, the
resealable closure comprises interlocking profiles on which the
caulking composition is disposed to provide a gas permeation
resistant seal in the resealable closure. The vacuum conduit
provides communication between the portable pump and the storage
portion of the evacuable bag, wherein the vacuum conduit comprises
at least a valve assembly and optionally a stand-off structure. In
one embodiment, the stand-off structure provides a means to
substantially eliminate the incidence of trapped air within the
storage area of the evacuable package. Each of the aspects of the
interlocking profiles, the caulking composition, the vacuum valve
assembly, the stand-off structure, and the vacuum pump are now
discussed in greater detail.
[0056] Referring to FIGS. 1a-1b, in one embodiment, the flexible,
resealable storage device 10 comprises a flexible material 12
shaped as an evacuable package 14 (also referred to as evacuable
bag). The flexible material 12 is preferably a plastic sheet 16,
such as polyolefin. The sheet 16 is, preferably, rectangular. In
one embodiment, the sheet 16 is folded over upon itself and two
lateral sides 15 are sealed adjacent to the periphery to provide an
opening 18 to a storage space 22. As such, the periphery of the bag
14 is substantially sealed. In another embodiment of the present
invention, the entire periphery of the evacuable bag 14 is heat
sealed.
[0057] In one embodiment of the present invention, the evacuable
package 14 may be a multilayer bag comprising an inner sealant
layer and a barrier/strength layer. The inner sealant layer may
comprise LDPE (low density polyethylene) or LLDPE (linear low
density polyethylene) and the barrier/strength layer may comprise
Nylon, PP (polypropylene) or PET (Polyester). As used herein the
term "low density" in conjunction with polyethylene denotes a
material having a density of no greater than 0.925 g/cm.sup.3, as
defined by ASTM standard D-15005-03, wherein the density may be
adjusted with the addition of ethylene vinyl acetate (EVA). Another
example of a multilayer bag and a method of forming a multilayer
bag is described in U.S. Pat. No. 4,267,960, titled "Bag For Vacuum
Packaging of Meats or Similar Products", filed Aug. 29, 1979, which
is incorporated herein by reference.
[0058] In the embodiments of the present invention in which the
evacuable bag 14 has an opening 18 to the storage space 22, the bag
opening 18 includes a resealable closure 20. The resealable closure
20 may include a set of interlocking profiles. In one example, the
set of interlocking profiles 21 may include resilient, selectively
engaging male and female profiles 21 (tongue-and-groove closure),
structured to seal the opening 18. It will be appreciated that
there are numerous interlocking profile geometries known, which can
be employed in the present invention.
[0059] With reference to FIG. 2, in one embodiment, the selectively
engaging profiles of closure 21 (also termed herein sometimes for
convenience as interengaging profiles) are positioned along two
opposing flexible flanges (also termed herein sometimes for
convenience as "panels") including a first flange 50 and a second
flange 52. As shown in FIG. 2, the two flexible panels 50, 52 may
include a raised surface 68, 69 on the inside surface of the panels
disposed outside the resealable closure. The first flange 50
includes a male profile having at least one protrusion 54 that
extends laterally across the bag 14. The second flange 52 includes
a female groove 60 defined by at least two protrusions (56,
58).
[0060] Still referring to FIG. 2, there may be multiple protrusions
62, 64, extending from the first and second flanges 50, 52 and
forming multiple corresponding male profiles and female grooves
(also termed herein sometimes for convenience as a female profile).
The protrusions 54, 56, 58, 62, 64 are generally formed from a
polyolefin material with a density of not less than approximately
0.925 g/cm.sup.3, preferably those described as a High Melt Index
polyolefin (HMI). More specifically, the protrusions 54, 56, 58,
62, 64 may comprise High Melt Index (MI) Polyethylene materials and
Ethylene Vinyl Acetate (EVA) Copolymers, particularly those having
a vinyl acetate content of from about 4 weight percent to about 12
weight percent. In addition, portions of the interengaging profiles
and/or surrounding closure structures may include one or more
features comprising low melt index or Ultra Low Density (ULD)
Polyolefins. As used herein, the term "Ultra Low Density" denotes a
density no greater than approximately 0.925 g/cm.sup.3. As will be
appreciated, the density may be adjusted with the addition of EVA.
At least one protrusion 54, 56, 58, 62, 64 may include a bead 66 of
polyolefin material with a density of not more than approximately
0.925 g/cm.sup.3. In some embodiments a bead 66 of softer material
is disposed at the tip of a protrusion 54, 56, 58, 62, 64 and is
structured to engage the opposing side 50, 52. The bead 66 of
softer material is hereafter referred to as a bead of sealing
material 66.
[0061] As discussed above, the bead of sealing material 66 may have
a lower density than the protrusions 54, 56, 58, 62, 64. During the
engagement of resealable closure 20, the lower density and hence
more compliant bead of sealing material 66 conforms to the geometry
of the higher density and more rigid material comprising the
portion of the closure against which the head of the profile abuts
upon engagement. The softer material abuts the closure with
increased conformance to the abutting surface, advantageously
providing a more effective seal against fluid exchange between the
interior of the package and the ambient, for example, the intrusion
of gas and the exterior atmosphere into the evacuable bag 14.
Regardless of the above described embodiments, the resealable
closure 20 and its associated interlocking structures can comprise
resilient materials of varying densities and melt indexes.
Accordingly, embodiments within the scope of the present
disclosure, including combinations of materials selected to achieve
sealant conditions under vacuum and reduced temperature
conditions.
[0062] The protrusions forming the male profile may also be
referred as a profile having a male head. The protrusions defining
the female profile (also referred to as a groove) may also be
referred to as profile having a female head and a fillet positioned
to provide a groove. The resealable closure 20 may further include
a closing clip structured to ensure the complete engagement of the
closure profiles. Specifically, the closure clip functions to
ensure that the interengaging profiles are engaged as the clip is
disposed along a first direction, but does not affect the
engagement of the profiles when disposed along the direction
opposite to that of the first direction.
[0063] Regardless of the specific details of construction or
interaction of the profiles 21 of resealable closure 20, the
interengaging portions of the resealable closure of the present
invention preferably includes a caulking composition 99 (also
sometimes referred to as sealing compound 99). For example, the
caulking composition 99 may be positioned on at least one
protrusion 54 on the first flange 50 and/or at least one protrusion
56, 58 on the second flange 52 of the closure 21, wherein the
caulking composition 99 assists in creating an air tight seal to
the storage space 22. Specifically, during engagement of the first
and second flange protrusions 54, 56, 58, 62, 64 of the male and
female profiles, the caulking composition 99 sits within the groove
60 to ensure an air-tight seal of the male and female profile.
Specifically, the caulking composition 99 is positioned to
infiltrate the void space defined between the engaged interlocking
profiles 21 of the resealable closure 20. Without being bound by
theory, it is believed that that the caulking composition 99 acts
to infiltrate gaps between the male and female profiles, thus
reducing the infiltration of ambient into the storage device 10
when it is placed in a condition of reduced pressure.
[0064] Accordingly, the resealable closure 20 is prepared before
sealing by introducing the caulking composition 99 onto one or more
members of the interengaging profiles 21 or onto a surface of the
resealable closure 20 proximal to the interengaging profiles 21, by
methods such as deposition or injection, where it will be
distributed during the interlocking process within incipient gaps
left between the interengaging profiles 21 after interlocking.
Alternately, prior to sealing the resealable closure 20, the
caulking composition 99 can be placed proximal to known areas in
which the sealing profile is prone to exhibit gapping, for example,
the ends of the male and female profiles 21 at the bag's periphery.
The portions of the male and female profiles at the bags periphery
are engaged by crush seal, which is often the site of leakage in
the closure device. The voids caused by the crush seal engagement
at the male and female profile may be filled with the sealing
compound 99 to substantially reduce the incidence of leakage.
[0065] The caulking composition 99 may comprise any material that
provides a selectively reversible air tight seal between the
interlocking profiles 21 of the resealable closure 20, in which the
caulking composition 99 is suitable for at least incidental contact
to food items inserted through the opening to the storage space.
Preferably, the caulking composition 99 maintains its chemical
structure throughout the operable temperature range of storage
device 10. The term "suitable" for at least incidental contact
denotes compounds that are eligible for compliance with or
equivalent to being in compliance with the Federal Food Drug and
Cosmetic Act (Title 21 of the Code of Federal Regulations)
standards for being generally recognized as safe (GRAS). The term
"at least incidental contact" includes at least the unanticipated
contact of food items being passed through the opening on which the
closure strip is positioned as the food items are being inserted
into the storage space. Although indirect contact between the
caulking composition and the food items is preferred, in some
embodiments the caulking composition may more directly contact the
food, so long as the interaction between the food items and the
caulking composition is in accordance with the regulations of the
Federal Food Drug and Cosmetic Act.
[0066] It is noted that caulking compositions that are suitable for
at least incidental food contact may be consistent with the
classification of materials for "lubricants with incidental food
contact" according to Title 21 of the United States Code of Federal
Regulations .sctn. 178.3570 (revised as of Apr. 1, 2003), so long
as the materials are consistent with the Federal Food Drug and
Cosmetic Act and have an operable temperature range suitable for
food storage and packaging. In some preferred embodiments, the
operable temperature range of the storage device is defined as the
temperature range that the storage bag is typically subjected to in
shipping, packaging and food storage applications, for example,
food storage applications ranging from approximately -10.degree. F.
to approximately 160.degree. F. One example of a caulking
composition that is listed as a "lubricant with incidental food
contact" according to Title 21 Of the United States Code of Federal
Regulations .sctn. 178.3570 and has an operable temperature range
suitable for food storage and packaging comprises
dimethylpolysiloxane. Another example is soy-based oils, for
example, those distributed by Cargill Corp., and soy-based
adhesives, for example, those distributed by DuPont as Pro-cote.TM.
soy polymers.
[0067] In order to provide an air tight seal, in some embodiments
the caulking composition 99 should be selected to have a work
penetration of about 290 to about 340, in which the work
penetration is measured at 60 strokes and a temperature of
77.degree. F. in accordance with the National Lubricating Grease
Institute (NLGI) system for rating greases by penetration and ASTM
D217-97 titled "Standard Test Methods for Cone Penetration of
Lubricating Grease" (1997). The NLGI classifies greases by
consistency numbers as measured by worked penetration. In a
preferred embodiment, the caulking composition 99 has a work
penetration on the order of about 290 to about 340 and is
classified as a grease having a NLGI consistency number equal to
approximately 2. Although it is preferred that the caulking
composition 99 have NLGI consistency number equal to approximately
2, greases having lower or higher NLGI consistency numbers may
alternatively be utilized, so long as the caulking composition 99
may be applied to the interengaging profiles 21 of the resealable
closure 20 using conventional injection methods and that the
caulking composition 99 is contained within the resealable closure
20 when exposed to temperatures consistent with food storage
container applications.
[0068] One example of a caulking composition 99, which meets the
above requirements is silicone grease. Silicone grease is an
amorphous, fumed silica thickened, polysiloxane-based compound.
Silicone grease is formed by combining liquid silicone with an
inert silica filler. One example of liquid silicone that may be
utilized in forming silicone grease having suitable work
penetration properties is polydimethylsiloxane having a specific
gravity on the order of about 0.973 and a viscosity greater than
about 300 centistokes, preferably on the order of about 350
centistokes. Fumed silica, an inert silica filler, has a chain-like
particle morphology and when incorporated into liquid silicone
forms three dimensional networks that trap the liquid and
effectively increases the liquid's viscosity.
[0069] Silicone grease may provide desired work penetration values
and temperature range to produce an adequately air tight seal
between the interengaged profiles 21 of the resealable closure 20
by selecting the proper proportions of inert silica filler to
liquid silicone. The proportion of inert silica filler to liquid
silicone is generally selected to ensure that separation of liquid
from solid in the silicone grease is substantially eliminated
throughout the operable temperature range of the bag as applied to
food container storage. In general, proportions of inert silica
filler to liquid silicone are selected to yield a silicone grease
viscosity that would not inhibit the application of the silicone
grease onto the resealable closure 20. The proportion of inert
silica filler to liquid silicone is preferably less than
approximately 30% by weight. Even more preferably, the proportion
of inert silica filler to liquid silicone is on the order of 6% by
weight.
[0070] In one highly preferred embodiment, the silicone grease is
provided by Clearco.TM. Silicone Grease (food grade) provided by
Clearco Products Co., Inc., Bensalem Pa. Clearco.TM. Silicone
Grease (food grade) has a work penetration value of about 290 to
about 340, in which the work penetration is measured at 60 strokes
and a temperature of 77.degree. F. Clearco.TM. Silicone Grease
(food grade) comprises 94% dimethylpolysiloxane and 6% fumed silica
by weight % and has a specific gravity on the order of about 1.1.
Clearco.TM. Silicone Grease may be utilized at temperatures ranging
from approximately -40.degree. F. to approximately 400.degree. F.
without chemical decomposition and is therefore well suited for
food storage applications. In this embodiment of the present
invention, the silicone grease 99 may be positioned along at least
one of the male and female profiles 21 of the resealable closure
20, wherein incidental contact to food being inserted into the
storage space of the storage device typically accounts for less
that 5.0 ppb of silicone grease being incorporated into the food
item being stored. In one embodiment, at least about 0.01 grams of
caulking composition per linear foot of resealable closure is
utilized, such as at least about 0.03 grams of caulking composition
per linear foot of the resealable closure. Generally, not greater
than about 0.07 grams of caulking composition is used per linear
foot of the resealable closure.
[0071] In another embodiment of the present invention, the caulking
composition 99 may comprise a soy adhesive. Similar to the
above-described caulking compositions, the soy adhesive preferably
is suitable for incidental food contact and has an operable
temperature range suitable for food packaging and storage. One
example of a soy adhesive is Pro-cote.RTM. soy polymer, which is
available from DuPont.TM.. In general, soy adhesive is prepared by
extracting and refining soy oil from dehulled, flaked soybeans. The
extracted material contains isolated soy protein in its native or
globular form; and soluble, low molecular weight sugars. The
extract is then processed in a controlled pH environment at tightly
controlled temperatures to uncoil globular native soy protein into
smaller units, and fractionating the material into uniform polymer
fractions. The isolated protein molecule fractions are highly
reactive and are chemically treated to modify the protein chain to
provide desired adhesive properties. Unmodified soy-based oils may
also be employed as a caulking composition. An alternative source
of soy based oils and adhesives is the soy products available from
Cargill.TM. Industrial Oils & Lubricants.
[0072] As will be appreciated, numerous reactive materials may also
be employed as caulking compositions. In particular, materials
which may be coated as separate reactants onto separate
interengaging portions of the closure which are admixed upon
engagement of the interengaging portions of the closure may be
utilized. Accordingly, when the closure parts are engaged the
admixed reactants will be combined, reacting and forming in-situ a
caulking composition which is infiltrated into a least one void
defined by the engaged interengaging portions of the closure. One
example of such a system comprises a free-flowing reactive polymer
liquid and a liquid cross-linking agent, each coated on separate
portions of the closure. In this example, when the closure is
engaged, the separate portions contact, admixing the polymer and
cross-linking agent, providing a viscous, cross-linked polymer
caulking composition which is infiltrated into voids in the closure
defined by the interengaged portions of the closure. Other examples
include the provision of a free-flowing liquid and a gelling agent
on separate portions of the closure to form a viscous caulking
agent upon admixture, and the provision of a two-part adhesive
material which react to form an adhesive upon admixture, for
example, formation of a pressure-sensitive adhesive. Other types of
chemical transformations will also be apparent to those of skill in
the art.
[0073] Referring now to FIG. 3, in another embodiment of the
present invention, the resealable closure structure includes at
least two sets of opposed interlocking profiles 150 respectively
having interengaging profiles 24, 28 and 23, 26 selectively engaged
in sealing the opening 18 to the storage space 22. Each pair of
interengaging profiles comprise a geometry having an asymmetrical
head 32, 36 extending from a stem 43. Each asymmetrical head is
preferably offset on the stem to complimentarily fit into the void
space defined by stem 43, post 38 and asymmetrical head 36. The
term "asymmetrical head" denotes that the centerline of the head
portion of the profile is substantially offset from the centerline
of the stem portion of the profile to which it is affixed.
[0074] The void space defined by stem 43, post 38 and asymmetrical
head 36 comprises a groove configured to selectively engage the
asymmetrical head 32 of the corresponding interengaging profile 23,
24. Stem 43, post 38 and asymmetrical head 36 are spaced to
selectively engage corresponding interengaging profiles 23, 24. The
spacing between the post 38 and stem 43, and between post 38 and
asymmetrical head 36 is sufficiently narrow to bias asymmetrical
head 32 toward asymmetrical head 36 when profiles 23, 24, 26, and
28 are engaged. The biased positioning of the asymmetrical head 36
in combination with the spacing of post 38 to correspond to the
width of asymmetrical heads 23, 24 defining a grove that reversibly
interlocks asymmetrical head 23, 24 into the groove when the
profiles are engaged.
[0075] Still referring to FIG. 3, the resealable closure further
includes a caulking composition 99 positioned on at least one of
asymmetrical heads 23, 24, 26, and/or 28. The caulking composition
99 may be deposited or injected onto the profiles 23, 24, 26,
and/or 28 insuring that an air tight seal is obtained when the
profiles 23, 24, 26, 28 are interengaged under varying temperature
and pressure conditions. The caulking composition 99 may be
positioned along the entire length of the opposed interlocking
profiles 150 or only a portion of the opposed interlocking profiles
150, such as the end portions of the opposed interlocking profiles
150 at the bag's periphery.
[0076] In another embodiment, shown in FIG. 4 (without showing
certain reference numbers for clarity), the resealable closure 20
includes a bead of caulking composition 100 in the gap between two
parallel sets of opposed interlocking profiles 150. In application,
as each set of opposed interlocking profiles 150 are interengaged,
the bead of caulking composition 100 contacts the ends of each set
of opposed interlocking profiles 150. In a preferred embodiment,
the bead of caulking composition 100 fills the void separating the
parallel sets of opposed interlocking profiles 150 and contacts the
female profiles grooves 26, 28 in each set of opposed interlocking
profiles 150, thereby creating a seal. In a further embodiment of
the present invention, the resealable closure structure 20 includes
a bead of caulking composition 100 in the gap between two parallel
sets of opposed interlocking profiles 150 and additional caulking
composition 99 between at least one set of interengaging profiles
(23, 26) and (24, 28).
[0077] In another embodiment, shown in FIG. 5 (without showing
certain reference numbers for clarity), the resealable closure 20
includes a bead of sealant material 45 in the gap between two
parallel sets of opposed interlocking profiles 150. The sealant
material 45 is a composition of high EVA & high MI polymers
selected to provide a high-conformance region in the closure, as
described above. Additionally, a bead of sealant material 53, 55
may be applied to the distal tip of each male profile 23, 24. In
general, suitable sealant material comprises compositions of
polymers as described above or alternatively ultra-low density
(ULD) polymers (as defined above) with EVA additives at a 2% or
higher loading. Beads of sealant material 45, 53, 55 ensure that an
air-tight barrier exists between substantially the entire length of
interengaging profiles (23, 26) and (24, 28) when the resealable
closure structure 20 is engaged. A bead of sealing material 45 may
also be positioned on both sides of a single set of opposed
interlocking profiles 150, as depicted in FIG. 6. Similar to the
above described embodiments, a bead of caulking composition may be
employed between parallel sets of opposed interlocking profiles
and/or the caulking composition may be employed between at least
one set of interengaging profiles (23, 26) and/or (24, 28).
[0078] Referring now to FIG. 7, in yet another embodiment of the
present invention, the resealable closure 20 may be provided by
resealable closure strips having independent and substantially
symmetric profiles 160, 162, 164, 166, unlike the embodiments above
utilizing asymmetrical structures. Accordingly, the heads
(described below) are not offset relative to the stems. That is,
each symmetric element 160, 162, 164, 166 includes a head 170 and a
stem 172. The head 170 is disposed generally symmetrically on the
stem 172. The symmetric profiles 160, 162, 164, 166 are disposed
with two elements of each panel 112, 114 and are spaced and
configured so that the gap between adjacent elements defines a void
region which has a shape corresponding to the shape of the
symmetric profiles 160, 162, 164, 166. This embodiment further
includes outer elements 180, 182. The outer elements 180, 182 are
offset toward the symmetric profiles 160, 162, 164, 166 and bias
the symmetric profiles 160, 162, 164, 166 into each other. The
outer elements 180, 182 are sized and shaped to correspond to the
outer most two symmetric profiles 160, 166. Similar to the above
described embodiments, a bead of caulking composition may be
employed between one or more of the symmetric profiles 160, 162,
164, 166. Additionally or alternatively the profiles may
incorporate a region of sealing material, as described above, for
example, by co-extrusion of the sealing material with the base
material comprising the profile. Resealable closures 20,
interengaging profiles 21, and profile members are well known, and
a variety of configurations are useable in accordance with the
principles of this disclosures; see, for example, U.S. Pat. Nos.
6,524,002; 6,152,600; 5,839,831; and 5,252,281, each of which is
incorporated herein by reference in its entirety.
[0079] Additionally, although not depicted in FIG. 7, multiple sets
of opposing interlocking profiles may be employed incorporating
independent and substantially symmetric profiles, wherein a bead of
caulking composition may be position between two sets of opposing
interlocking profiles. The bead of caulking composition may be
employed separately or in conjunction with caulking composition
disposed between each of the symmetric profiles. It is noted that
the present invention is not limited to profile geometries
disclosed above, as any profile geometry may be utilized and is
within the scope of the present disclosure, so long as the geometry
of the profiles is compatible with the caulking composition in a
manner that provides an air-tight seal.
[0080] Referring to FIG. 8, in one embodiment of the present
invention, the resealable closure 20 comprises a opening and a
clamping means. The clamping means may comprise a clip 170 that is
separate from the evacuable bag 14, in which the clip 170 seals the
opening 18 of the bag 14 in clamp seal engagement. In another
embodiment the clamping means may further include a mandrel 171,
wherein the opening 18 of the evacuable bag 14 is rolled around the
mandrel 171 and the clip 170 compresses the portion of the
evacuable bag 14 rolled about the mandrel in clamp seal
engagement.
[0081] Referring back to FIG. 1a, the storage device 10 further
includes a vacuum conduit having one end in fluid communication
with the interior of the storage space 22 and which includes a
vacuum valve assembly 30. The vacuum valve assembly 30 is in fluid
communication with the storage space 22 and defines a sealable
passage through which liquids and/or gases may be drawn. The vacuum
valve 30 is often a one-way evacuation valve, allowing fluid flow
therethrough in only one-direction; generally, the direction is
from storage space 22 of evacuable package 14 to the exterior of
evacuable package 14.
[0082] Referring to FIG. 9, in one embodiment the vacuum valve
assembly 30 includes a base 31 having a flat surface 33 with at
least one opening 37 there through, a resilient valve element 35,
and an alignment device 39. The base 31 is sealingly engaged to the
evacuable bag 14. The valve element 35 is generally flat and
disposed adjacent to the flat surface 33. The alignment device 39
is coupled to the base 31 and is structured to bias the valve
element 35 against the flat surface 33. The valve element 35 is
structured to move between a first position, wherein the opening 37
is open, and a second position, wherein the opening 37 is sealed.
The valve element 35 is normally biased to the second position. The
base 31 has a defined shape, such as, but not limited to a concave
disk. The outer surface 41 of the base 31 is a generally flat
torus.
[0083] The vacuum valve 30 can be any suitable valve, including
those known as "Goglio" type or "Raackmann" type. Goglio-type
valves are available, for example, from Bosch, Wipf, and Wico;
Raackmann-type valves are available, for example, from Amcor. Other
examples of suitable vacuum valves 30 include those described in
U.S. Pat. Nos. 6,913,803; 6,733,803; 6,607,764; and 6,539,691, each
of which is incorporated herein by reference in its entirety. In
one embodiment of the present invention, the vacuum valve assembly
may be consistent with the valves disclosed in U.S. Patent
Application Publication 11/100,301, entitled "EVACUATABLE
CONTAINER", filed Apr. 6, 2005. It is noted that the sealing nature
of the valve element 35 may be enhanced by incorporating a sealing
material and/or a caulking composition into the sealing members of
the valve assembly. In another embodiment, the vacuum valve
assembly 30 may further include at least one rib (not depicted)
extending from the interior side of the valve assembly base 31,
wherein the rib extending from the base 31 ensures that the valve
assembly is not obstructed during application of the vacuum.
[0084] As shown in FIGS. 1a-1b, 10a-10c, 11a-11d, and 15, the
storage device 10 further includes a stand-off structure 70. The
stand-off structure 70 provides a communicating passage for the
removal of liquids and gases. This is, preferably, a strip 71 of
film having a pattern of channels 72 embossed, or cut, therein. The
stand-off structure channels 72 are designed not to collapse even
when the bag 14 is placed under a vacuum. The channels 72 may be in
any shape, such as, but not limited to a honeycomb pattern (FIG.
10a), a grid or partial grid (FIG. 10b), a series of parallel
grooves (FIG. 10c) or a series of triangular columns (FIG. 11c).
Referring to FIG. 15, the cavity face 85 of the stand-off structure
70 faces the vacuum valve assembly 30 and the protrusion face 86 of
the stand-off structure 70 faces the storage space 22.
[0085] The honeycomb pattern of channels is depicted in isometric
view in FIG. 11a, in which the channels 72 that provide the
communicating passage for the removal of liquids and gases is
defined by a series of polyhedron structures 100. Referring now to
FIG. 11b, in another embodiment of the stand-off structure 70, the
pattern of channels 72 for the removal of liquids and gasses may be
provided by a series of curvilinear columns 120.
[0086] Regardless of the geometry selected for providing the
channels, the stand-off structure 70 produces a passage for the
removal of liquids and gases by providing a cross-section with a
series of raised surfaces and recessed surfaces. In one embodiment,
the standoff structure is integral with a fluid conduit providing
fluid communication between the interior of the storage device and
a vacuum system by which the storage device is evacuated, and which
comprises a vacuum valve, the standoff structure, optionally a
quick-connect device, optionally a liquid/vapor separator and the
suction side of a vacuum pump. Referring to FIG. 12a, channels 72
are provided in the area defined between the raised surfaces 74 and
recessed surfaces 75 of the stand-off structure's 70 cross-section.
The stand-off structure 70 may have a series of channels 72 on one
side of the standoff structure 70, as depicted in FIG. 12a, or on
both sides of the stand-off structure 70, as depicted in FIG. 12b.
Referring to FIG. 11c, in one embodiment of the present invention,
the cavity face 85 of the stand-off structure 70 comprises channels
72 and the protrusion side 86 comprises a series of communicating
passages produced by a plurality of polyhedron structures.
[0087] As shown in FIGS. 13a-13d, 14 and 15, the stand-off
structure 70 may be bonded to the inner side of the bag 14, on the
same side of the evacuable bag 14 as the vacuum valve assembly 30.
Although thermal bonding of the stand-off structure 70 to the side
of the evacuable bag 14 is preferred, any conventional bonding
method may be utilized as known by those skilled in the art. The
stand-off structure 70 is positioned at a location corresponding to
the location of the vacuum valve assembly 30. Multiple valve
assemblies 30 and multiple stand-off structures 70 may be utilized
in a single storage device 10, as depicted in FIG. 13d.
[0088] As shown in FIG. 13a, the coupling of the stand-off
structure 70 may be accomplished prior to folding over the plastic
sheet 16, wherein the entire side periphery 73 of the stand-off
structure is bound to the plastic sheet 16. Referring to FIG. 13b,
in another embodiment, the coupling of the stand-off structure 70
to the storage device 10 may be accomplished by bonding only
selected portions of the stand-off's side periphery 73 to the
plastic sheet 16. Additionally, as opposed to limiting the
stand-off structure 70 to a single side of the storage device 10,
the stand-off structure 70 may be coupled to extend across both
sides of the bag 14, as shown in FIG. 13c. In another example, the
stand-off structure 70 may be positioned to extend diagonally
across the plastic sheet as depicted in FIG. 13d. It is noted that
examples depicted in FIGS. 13a-13d have been provided for
illustrative purposes and that other configurations in the
positioning of the stand-off 70 are within the scope of the present
invention, so long as the stand-off 70 is positioned to be in fluid
communication with the vacuum valve assembly 30 in a manner that
allows for the removal of liquids and gasses from the storage
device 10.
[0089] FIG. 14 depicts the positioning of the stand-off structure
70 once the plastic sheet 16 is folded over upon itself and two
lateral sides 15 are sealed adjacent to the periphery forming the
storage space 22. In the illustrated embodiment, the stand-off
structure 70 is depicted as being bound to the face of the plastic
sheet 16 within the storage space 22, wherein the channels 72 of
the stand-off structure 70 face the surface of the plastic sheet 16
to which the stand-off structure 70 is bound. In an alternate
embodiment, the stand off structure 70 may include channels 72 on
both sides of the stand off structure 70 (FIG. 12b), in which the
channels on a first side of the stand off structure 70 face the
surface of the plastic sheet 16 to which the stand-off structure 70
is bound and the channels 72 on the second side of the stand off
structure 70 face the opposing plastic sheet.
[0090] FIG. 15 illustrates the cross-section of the storage device
10 depicted in FIG. 14 along reference line 9-9, in which the
channels 72 of the stand-off structure 70 are clearly depicted as
facing away from the storage space 22 and towards the vacuum valve
assembly 30 as well as the surface of the plastic sheet 16 to which
the stand-off structure 70 is bound. Prior to the application of a
vacuum, the portion of the stand-off structure 70 opposing the
vacuum valve assembly 30 may be separated from the vacuum valve
assembly 30 by a distance D1 ranging from about 0.003'' to about
0.25''.
[0091] In one application, a vacuum pump is attached to the vacuum
conduit which includes at least one vacuum valve and in fluid
communication therewith, at least one standoff structure. The
vacuum pump is operated, applying a vacuum to the interior of the
storage device through the vacuum valve assembly 30 and standoff
assembly causing the storage space 22 to collapse upon a food
article contained therein. During the application of the vacuum,
the stand-off structure 70 separates the food article from the
vacuum valve assembly 30, ensuring that the food article does not
obstruct the flow of air or liquids to be removed from the storage
space 22, and insuring that the walls of the storage device conform
tightly to the food article. Additionally, as the vacuum causes the
portion of the plastic sheet 16 opposing the stand off structure 70
to collapse upon the raised portions of the stand-off structure 70,
any remaining liquid and air may be removed via the stand-off
structure's 70 recessed channels. During the application of the
vacuum, the distance D1 separating the vacuum valve assembly 30
from the opposing raised surfaces of the stand-off structure 70 may
be substantially eliminated while maintaining an effective
passageway for removing the remaining air and liquids from the
storage device through the stand-off structure's 70 recessed
channels.
[0092] The evacuable package 14 may be produced via any suitable
processes. For example, the evacuable package may be made by a
horizontal process (e.g., where the flexible material 12 forming
side panels 17, 19, and resealable closure 20 move in a generally
horizontal direction), a vertical process (e.g., where the flexible
material 12 forming side panels 17, 19, and resealable closure 20
move in a generally vertical direction), and combinations
thereof.
[0093] In one general embodiment of a horizontal process, two
extended lengths of the flexible material 12, each forming a side
panel 17, 19 move in a generally horizontal direction. An extended
length of resealable closure 20 may be attached to side panels 17,
19 or may already be integral with the flexible material 12. A
stand-off structure 70 can be attached to one or more of the side
panels 17, 19, or can be integral with side panels 17, 19, or can
be side panels 17, 19. A vacuum valve 30, and an optional
corresponding hole, are typically installed into/produced in one of
the extended lengths of flexible material 12 at predetermined
intervals, to correspond to one vacuum valve 30 per evacuable
package 14. After the various elements have been joined to form an
extended length, seals, which will result in lateral sides 15 and
bottom edge 13 may be made. Lateral seal portions (not illustrated)
which are seals located proximal the overlap of the lateral sides
15 and the resealable closure 20, are usually made (e.g., crushed)
simultaneously with the lateral sides 15 seals, but could be made
in a separate step.
[0094] In alternate embodiment of a horizontal process, one
extended length of flexible material 12 moves in a generally
horizontal direction. This flexible material is folded to form both
side panels 17, 19 and bottom edge 13. Any order of applying
resealable closure, stand-off structure 70 and vacuum valve 30 can
be used. Similar to the above embodiment, after the various
elements have been joined to form an extended length, the lateral
sides 15 and lateral seal portions ma y be made.
[0095] In one embodiment of a vertical process, two extended
lengths of the flexible material 12, each forming a side panel 17,
19 move in a generally vertical downward direction. Similar to
above, an extended length of resealable closure 20 may be attached
to the side panels 17, 19, before, after, or concurrently with the
bottom 13 being sealed, or the resealable closure 20 may already be
integral with the flexible material 12. A stand-off structure 70
can be attached to one or more of the side panels 17, 19, or can be
side panels 17, 19. A vacuum valve 30, and an option corresponding
hole, are typically installed into/produced in one of the extended
lengths of flexible material 12 at predetermined intervals, to
correspond to one vacuum valve 30 per evacuable package 14. After
the various elements have been joined to form an extended length,
seals, which will result in lateral sides 15 may be made. Lateral
seal portions (not illustrated) which are seals located proximal
the overlap of the lateral sides 15 and the resealable closure 20,
are usually made (e.g., crushed) simultaneously with the lateral
sides 15 seals, but could be made in a separate step.
[0096] In alternate embodiment of a vertical process, one extended
length of flexible material 12 moves in a generally vertical
direction. This flexible material is folded to form both side
panels 17, 19 and bottom edge 13. Any order of applying resealable
closure, stand-off structure 70 and vacuum valve 30 can be used.
Similar to the above embodiment, after the various elements have
been joined to form an extended length, the lateral sides 15 and
lateral seal portions may be made.
[0097] It will be appreciated that the resealable closure structure
20, shown in FIG. 1a, may be operated by hand, however, as shown in
FIGS. 1, 16a and 16b, the resealable closure 20 may also include a
closing clip 80 and end clips 82. The closing clip 80 is a rigid
U-shaped member 84 structured to fit snugly over at least the first
and second side protrusions 54, 56, 58. The U-shaped member 84 is
structured to bias the male protrusion 54 into the groove 60 formed
by the other protrusions 56, 58 as the U-shaped member 84 is moved
over the protrusions 54, 56, 58. In the embodiments of the present
invention incorporating multiple protrusions, the U-shaped member
84 may be structured to also fit snugly over multiple protrusions
62, 64, wherein the U-shaped member also biases at least one
additional male protrusion 62 into at least one additional groove
formed by the other protrusions 64. The closure clip 80 functions
to ensure that the interlocking profiles 21 are engaged as the clip
80 is disposed along a first direction, but does not affect the
engagement of the interlocking profiles 21 when disposed along the
direction opposite to that of the first direction. More
specifically, the closure clip 80 does not separate the
interlocking profiles when being traversed over engaged
interlocking profiles 21. The end clips 82 are bonded to the ends
of the resealable closure 20 and arrest the motion of the closing
clip as it traverses the bag 14. The cross-section of an end clip
is depicted in FIG. 17.
[0098] As mentioned above, in one embodiment the reclosable storage
device comprises a portion of a system which includes a vacuum
device having a low pressure side attached to a vacuum conduit
which is in fluid communication with the interior of the storage
device and which conduit includes a vacuum valve (described above).
Optionally, the assembly includes also a quick-disconnect means in
the vacuum conduit between the vacuum pump and the storage device
and optionally includes a gas/liquid separator means in the vacuum
conduit between the suction side of the vacuum pump and the storage
device.
[0099] As will be appreciated, any number of vacuum devices can be
utilized to evacuate a reclosable storage device in accordance with
the present invention, however, in some embodiments, it is
preferred to employ a hand-held or portable vacuum pump. An example
of one suitable portable device is illustrated in FIG. 21. The
portable vacuum pump assembly illustrated in FIG. 21, pump 40,
includes a power source, such as a battery, a vacuum pump having a
suction side and an exhaust side, and a motor, (all not shown). The
vacuum pump may be connected to the fluid conduit connected to the
interior of the storage device by a quick-connect means, wherein
one portion of the quick-connect means is integral with the vacuum
pump assembly and another portion of the quick-connect means is
integral with the flexible storage device. An example of this is
illustrated in FIG. 1 as engagement end 42 of vacuum pump 40. As
illustrated, engagement end 42 has a defined shape, for example, a
convex disk, concave disk or a disk shaped to fit within the medial
opening of the outer surface of a vacuum valve assembly's defining
one end of a fluid conduit associated with a storage device. The
engagement end 42 has a defined shape structured to engage the
vacuum valve assembly 30 and defines a passage that is in fluid
communication with the vacuum pump 40. Thus, the engagement end of
the portable vacuum pump 40 may function as a quick-connect means,
for example, as illustrated in FIGS. 18(a) and 18(b) a suction cup
tip 260, in which the suction cup tip 260 incorporates integrated
stand off structures 261 to maintain suction during application of
the vacuum as depicted in FIGS. 18(a) and 18(b). It is noted that
other quick-connect means, for example, vacuum tips (engagement end
42) have been contemplated and are within the scope of the present
invention, so long as the engagement end 42 geometry provides a
quick connect engagement with the vacuum valve assembly. A "quick
connection engagement" requires sealing of the vacuum valve
assembly 30 and engagement end 42 without separate fasteners or the
removal of separable sealing members. It will be appreciated that
the system may also utilize more conventional coupling means to
join the vacuum system to the fluid conduit to provide fluid
communication between the suction side of the vacuum pump and the
interior of the storage device.
[0100] As shown in FIGS. 19 and 20, the assembly may also include a
liquid separator assembly 90. The liquid separator assembly 90 is
structured to collect a liquid, while allowing gases to be drawn
into the suction side of the vacuum pump assembly 40. In one
embodiment, the liquid separator assembly 90 includes a tube 92,
and accumulator housing 94 and a diverter 96. The tube 92 further
includes a base 98 structured to sealingly engage both the
attachment end 42 and the accumulator housing 94. The accumulator
housing 94 is shaped as a cup and is structured to contain a
liquid. The diverter 96 is structured to engage the distal end of
the tube 92 and redirect the fluid flow from an axial direction in
the tube 92 into the accumulator housing 94. Thus, when assembled,
the attachment end 42 is coupled to the lower side of the tube base
98 and the accumulator housing 94 is coupled to the upper side of
the tube base 98. The diverter 96 is disposed at the distal end of
the tube 92. Thus, there is a fluid passage from the attachment end
42 into the accumulator housing 94.
[0101] In operation, the portable vacuum pump 40 is structured to
engage the vacuum conduit connected to the interior of the storage
device, for example, as illustrated, the outer surface of the
vacuum valve assembly 30. When the portable vacuum pump 40 is
engaged and actuated the vacuum valve assembly 30 is actuated by
the resultant pressure differential, the valve element 35 moves
into the first position (described above) and the vacuum conduit
passage is open and fluid (gas and liquid) is withdrawn from the
bag 14 through the vacuum conduit into the suction side of the
vacuum pump. The fluid may be both liquid and gas. When a separator
assembly is present in the vacuum conduit, liquid and gas are drawn
into the liquid separator assembly 90, the liquid contacts the
diverter 96 and is deposited in the accumulator housing 94. Thus,
the liquid is not drawn with the gas towards the vacuum pump. The
gas is exhausted via the vacuum pump from the vacuum pump assembly
40. When the accumulator housing 94 needs to be emptied, a user may
simply remove the tube 92 and base 98 allowing the liquid to drain
from the vacuum pump assembly 40.
[0102] When a portable vacuum pump 40 is actuated, air is withdrawn
from the storage space 22. Thus, as shown in FIG. 21, an item, such
as a food article 1 shown in ghost, may be placed in a storage
device 10. The stand-off structure 70 is structured to prevent the
plastic sheet that forms the evacuable bag 14, or an item within
the bag 14, from obstructing the vacuum valve assembly 30. That is,
the channels 72 on the stand-off structure 70 provide a path for
liquids and gases within the bag 14 to reach the vacuum valve
assembly 30. In the embodiments of the invention in which the
stand-off assembly has channels positioned on both sides of the
stand-off structure 70, the channels contacting the item contained
within the bag ensures that liquids and gasses are not trapped
between the stand-off structure 70 and the item contained within
the storage space.
[0103] To further assist in facilitating the removal of fluids from
the evacuable package 14 to form a vacuum, it may be useful to
restrict flow of solids and/or liquids proximal the valve 30. Thus,
in one embodiment, one or more barriers may be utilized proximal at
least a portion of the vacuum valve 30. These barriers may be a
part of the stand-off structure 70, or may be separate from the
stand-off structure 70. One embodiment of a useful barrier
arrangement is illustrated in FIG. 22a. In the illustrated
embodiment, the evacuable package 14 includes a vacuum valve 30
surrounded by a plurality of barriers 76. The plurality of barriers
76 at least assist in defining a plurality of channels 77, which
assist in providing fluid communication between the vacuum valve 30
and the storage space 22 of the evacuable package 14. The barriers
76 generally interconnect a first side of the evacuable package 14
to a second opposing side of the evacuable package 14, thereby
restricting movement of fluids and/or liquids into and/or proximal
the vacuum valve 30.
[0104] The plurality of barriers 76 may be formed by any suitable
methods. For example, at least a portion of the first side panel 17
of the evacuable package 14 may be bonded to a portion of the
second side panel 19 of the evacuable package 14 (e.g., via heat
sealing and/or an adhesive), thereby creating one or more barriers
76 integral with both these first and second side panels 17, 19.
Thus, the barriers 76 may comprise an uninterrupted span from the
first side panel 17 to the second side panel 19 of the evacuable
package 14. In one embodiment, the barriers 76 consist essentially
of portions of the first and second side panels 17, 19 of the
evacuable package 14. In another embodiment, a polymeric material
may be bonded to each of the first and second side panels 17, 19 of
the evacuable package 14 to provide the barriers 76. In the
illustrated embodiment, the plurality of barriers 76 are
intermittently spaced about at least a portion of the vacuum valve
30. Thus, the plurality of barriers 76 at least assist in defining
a portion of one or more of the channels 77.
[0105] The barriers 76 may be spaced about the valve 30 in any
suitable arrangement. By way of example, the barriers 76 may define
at least a portion of an ellipse, as illustrated in FIG. 22a. In
another example, and with reference to FIG. 22b, the barriers 76
may be located in a non-linear and/or non-elliptical fashion about
at least a portion of the periphery of the valve 30. In another
embodiment, and with reference to FIG. 22c, at least some of
barriers 76 may be disposed on a line, thereby defining a sealing
line. This sealing line may be oriented in any manner relative the
valve 30, but is generally oriented transverse to at least one
lateral side 15 of the evacuable package 14. One particularly
useful aspect of this embodiment is that the sealing line may
assist in providing a visual indicator to a user of the evacuable
package 14 regarding the filling limits of the evacuable package
14. More particularly, the sealing line may be visible from the
exterior of the evacuable package 14, thereby facilitating visual
confirmation of a fill level for the evacuable package 14 by a
user.
[0106] In a related embodiment, a separate visual indicator may be
utilized on the exterior of the evacuable package 14. This visual
indicator may correspond with the orientation of the sealing line.
Thus, the fill level of the evacuable package 14 may be further
emphasized. In one embodiment, the visual indicator is a color
indication and/or a textural indication. This visual indicator may
also be utilized without the use of barriers 76, thereby providing
an external visual indicator to a user of the fill level of the
evacuable package.
[0107] As illustrated in FIGS. 22a and 22b, the barriers 76 may be
utilized without a stand-off structure 70, thereby reducing
material costs associated with production of the evacuable package
14. In another embodiment, a stand-off structure 70 may be used in
conjunction with the barriers 76. For example, a stand-off
structure 70, such as described above, may be utilized proximal the
barriers 76. In a particular embodiment, and as illustrated in FIG.
22c, at least a portion of some of the plurality of barriers 76 may
overlap with the stand-off structure 70, thereby providing various
fluid evacuation pathways and further assisting in removal of
fluids from the evacuable package 14. In one embodiment, the
barriers 76 are a portion of the stand-off structure 70.
[0108] The plurality of barriers 76 may be located in any suitable
location within the evacuable package 14. As described above, the
plurality of barriers 76 may be located proximal the periphery of
the vacuum valve 30. In another embodiment, and with reference to
FIG. 22d, the barriers 76 may be located proximal at least a
portion of the perimeter of evacuable package 14. In this
embodiment, a plurality of barriers 76a-76h may at least assist in
defining a plurality of pathways 78 and channels 77a-77d via which
fluids may flow to the vacuum valve 30. In the illustrated
embodiment, a first barrier 76a is located proximal the vacuum
valve 30 and is substantially parallel to a lateral side 15a of the
evacuable package 14. A second barrier 76b is also located proximal
the lateral side 15a of the evacuable package 14 and is offset from
the first barrier 76a, thereby defining at least a portion of a
channel 77a through which fluids may flow to the vacuum valve 30. A
third barrier 76c is interconnected to the second barrier 76b and
is substantially orthogonal to the second barrier 76b. Thus, the
third barrier 76c is located substantially parallel to the bottom
13 of evacuable package 14 and is substantially orthogonal to the
lateral sides 15a, 15b of the evacuable package 14. A fourth
barrier 76d is also located substantially parallel to the bottom 13
of the evacuable package 14 and is offset from the third barrier
76c, thereby defining a channel 77b through which fluids may flow
to the vacuum valve 30. In turn, barriers 76e, 76f, 76g and 76h may
also be utilized to define channel 77c and channel 77d through
which fluids may flow to the vacuum valve 30. These barriers may be
formed as described above, such as by a heat sealing and/or an
adhesive. A vacuum pump 40 may be utilized in conjunction with the
vacuum valve 30 to remove at least a portion of the fluids within
the evacuable package 14 via pathways 78, channels 77a, 77b, 77c
and 77d.
[0109] As may be appreciated, a resealable closure 20 may also be
utilized in accordance with any of the above referenced barrier
embodiments. For example, and with continued reference to FIG. 22d,
a resealable closure 20 may be utilized in conjunction with the
evacuable package 14 and plurality of barrier structures 76a-76h.
The resealable closure 20 may also be used with any of the
embodiments as described above and with any of the embodiments
illustrated in FIG. 22a-22c.
[0110] As noted above, a stand-off structure 70 may be utilized
within the evacuable package 14 to facilitate fluid communication
between the interior of the evacuable package 14 and the vacuum
valve 30. As may be appreciated, extra materials and/or handling
time may be required to interconnect the stand-off structure 70 to
the interior of the evacuable package 14. Thus, in one embodiment
of the present invention, a resealable closure comprising a
stand-off structure may be used. One embodiment of such a
resealable closure is illustrated in FIGS. 23, 24 and 25a-25c, in
which the evacuable package 14 may include a resealable closure 230
that includes at least a portion of the stand-off structure 70
and/or the vacuum valve 30. The use of such resealable closure 230
may facilitate restricted manufacturing time and/or decrease
material costs, as will be described in further detail below.
[0111] Referring now to FIGS. 25a-25c, the evacuable package 14
includes a resealable closure 230 that includes a first flange 50,
such as described above, and a second flange 52'. The second flange
52' includes a top portion 52a, such as the second flange 52
described above. The second flange 52' also includes a skirt
portion 52b interconnected to, and often integral with, the top
portion 52a. The skirt portion 52b comprises a stand-off structure
70, such as any of the stand-off structures described above. In one
embodiment, the stand-off structure 70 is an embossed structure, as
will be described in further detail below. Each of the flanges 50,
52', may include the interengaging profiles 21, such as any of the
interengaging profiles described above.
[0112] The second flange 52' may include a vacuum valve 30
interconnected therewith. In this regard, any of the vacuum valve
assemblies described above may be utilized in conjunction with the
skirt portion 52b of the second flange 52'. For example, a hole may
be punched in the skirt portion 52b followed by interconnection of
a vacuum valve 30 to the skirt portion 52b relative to the punched
hole. In another embodiment, and as described in further detail
below, the vacuum valve 30 may be integral with the skirt flange
portion 52b, where the vacuum valve 30 is formed via ultrasonic
welding and/or thermal heating techniques.
[0113] The top portion 52a and skirt portion 52b of the resealable
closure 230 may comprise any suitable material. For example, the
top portion 52a may comprise a first polymeric material (e.g.,
low-density polyethylene (LDPE) or linear-low density polyethylene
(LLDPE)) having a melting point of about at least about 350.degree.
F., such as at least about 370.degree. F. The skirt portion 52b may
comprise this same first polymeric material, or the skirt portion
52b may comprise a second polymeric material. For example, it may
be desirable to facilitate bonding of a vacuum valve 30 to the
skirt portion 52b without substantial degradation of the skirt
portion. Thus, in one embodiment, the skirt portion 52b may
comprise a polymeric material having a melting point of at least
about 275.degree. F., such as at least about 350.degree. F., or at
least about 400.degree. F., or even at least about 420.degree. F.
to facilitate ultrasonic welding of and/or thermal bonding of the
vacuum valve 30 to the skirt portion 52b. One useful material in
this regard is medium density polyethylene (MDPE).
[0114] In a related approach, the top portion 52a may have an
average thickness, excluding the interengaging profiles 21, such as
at least about 3 mils. The skirt portion 52b may have an average
thickness, such as at least about 10 mils, 20 mils or even at least
about 30 mils. In the latter regard, bonding of the vacuum valve 30
to the skirt portion 52b may be facilitated due to the increased
thickness of the skirt portion 52b. In one approach, the ratio of
the thickness of the skirt portion 52b to the thickness of the top
portion 52a is at least about 1.5:1, such as at least about 3:1, at
least about 5:1, or even at least about 10:1.
[0115] The first flange 50 and second flange 52' of the resealable
closure 230 may be produced by any known or developed techniques.
One embodiment for creating a resealable closure 230 comprising a
stand-off structure 70 is illustrated in FIG. 26. In the
illustrated embodiment, the second flange 52' is fed between an
anvil roll 87 and an embossing roll 88, the embossing roll 88
including an embossing portion 91 and a non-embossed portion 89. As
the second flange 52' is fed through the anvil roll 87 and the
embossing roll 88, the embossing portion 91 embosses the skirt
portion 52b of the second flange 52', thereby providing a stand-off
structure 70 thereon. The intermittent non-embossed portion 89 of
the embossing roll 88 facilitates production of non-embossed
portions 79 of the skirt portion 52b of the second flange 52'. Such
non-embossed portions 79 facilitate a hermetic seal at the lateral
edges 15 of the evacuable bag 14 by providing a relatively smooth
surface for welding of ends of the resealable closure 230 to the
flexible material 12 of the evacuable bag 14.
[0116] The embossing may be accomplished while the resealable
closure 230 is in a cold form, such as prior to the resealable
closure 230 being interconnected with the flexible material 12,
which results in construction of the evacuable package 14.
Alternatively, the skirt portion 52b may be embossed while the
resealable closure 230 is being manufactured. In this regard, the
resealable closure 230 could then be immediately fed to an
apparatus for interconnection of the resealable closure 230 to the
flexible material 12, thereby facilitating increased manufacturing
efficiency.
[0117] As noted above, a vacuum valve 30 may be utilized in
conjunction with the resealable closure 230 and stand-off structure
70. In one approach, a vacuum valve assembly 30 may be
interconnected to the resealable closure 230, such as via thermal
welding, chemical bonding, or adhesives. In this regard, a hole may
be punched through a portion of the resealable closure 230, after
which a vacuum valve 30 may be positioned relative to the hole and
bonded thereafter to the resealable closure 230.
[0118] In another embodiment, a vacuum valve may be formed integral
with the resealable closure 230. One system for forming such a
vacuum valve is illustrated in FIG. 27a. In the illustrated
embodiment, a valve forming source 46, such as an ultrasonic
forming source or a thermal forming source, is used to form the
vacuum valve 30 via tip 47 and anvil 48. More particularly, the
resealable closure 230 may be placed between the anvil 48 and the
valve forming source 46. A portion of the resealable closure 230
(e.g., a skirt portion) may be contacted by a die 49 of the anvil
48, while an opposing side of the same portion of the resealable
closure 230 is subjected to energy from the valve forming source.
The energy (e.g., ultrasonic and/or thermal) provided to that
portion of the resealable closure 230, in conjunction with the die
49, mold that portion of the resealable closure 230 into the
desired valve shape. For example, the thermoplastic molding
techniques described in any of U.S. Pat. Nos. 6,569,368; 6,981,936;
6,840,675; 6,733,622; 6,662,410; 6,036,796; and 5,948,337 may be
used to form the vacuum valve 30. Valves of this type are available
from ENR Group, Inc. of Slinger, Wis. As may be appreciated, this
process may be applied to a single resealable closure 230, as
illustrated in FIG. 27a, or may be applied to a strip containing a
plurality of resealable closures 230, as illustrated in FIG.
27b.
[0119] As may be appreciated, various types of food products may be
utilized in accordance with the present invention. For example, raw
meats may often be utilized within the evacuable package 14. Such
meats may include various liquids, such as blood, which, while
non-frozen, may appear normal to a user. However, upon removal of
fluids from the evacuable package 14, such as via the vacuum pump
40 described above, followed by freezing of the meat, portions of
liquids within the evacuable package 14 may streak and/or otherwise
provide a undesirable visual appearance to a user. Thus, in one
embodiment of the present invention, a wicking material may be
utilized in conjunction with the evacuable package 14 to facilitate
wicking of liquids away from food products, thereby restricting
possible undesired visual effects. One embodiment of such an
evacuable package 14 is illustrated in FIG. 28. In the illustrated
embodiment, the evacuable package 14 includes a resealable closure
20, such as described above, a vacuum valve 30, such as described
above, and a stand-off structure 70, such as described above. The
evacuable package 14 also includes a plurality of barriers 76,
which at least assist in defining a plurality of channels 77, such
as described above. The plurality of barriers 76 define wicking
section WS, which allows for the wicking of liquids into a wicking
material 93. More particularly, fluids from the storage space 22 of
the evacuable package 14 may drawn to and/or flow through channels
77 and into the wicking section WS. The wicking material 93
collects such liquids, thereby removing those liquids from the
central portion of the storage space 22 of the evacuable package
14, which may assist in reducing undesired visual effects from
freezing of a material. The barriers 76 also restrict the wicking
material 93 from movement outside of the wicking section WS of the
evacuable package 14.
[0120] In another embodiment, the wicking material 93 is utilized
within the storage space 22 of the evacuable package 14 without the
use of barriers 76. In this embodiment, an adhesive or other
suitable type of bonding material may be utilized to adhere the
wicking material 93 to one or more of the side panels 17, 19 of the
evacuable bag, thereby restricting movement of the wicking material
93 within the evacuable package 14.
[0121] The wicking material 93 may be may be any material adapted
to wick, adsorb or absorb liquids. For example, the wicking
material 93 may be a cellulose-based material, such as paper, or a
synthetic absorbent (e.g., a sponge), a desiccant material, or any
other material adapted to wick, adsorb or absorb liquids. The
wicking material 93 may be associated with the evacuable package 14
at any suitable time. In one approach, the wicking material 93 is
applied to at least one side of the flexible material 12 during the
production of the evacuable bag 14. For example, a label-type
applicator may be utilized to apply a paper-type wicking material
to the flexible material 12 at any suitable time during a
horizontal or vertical bag manufacturing process, as described
above.
[0122] While illustrative embodiments of the invention are
disclosed herein, it will be appreciated that numerous
modifications and other embodiments may be devised by those skilled
in the art. Therefore, it will be understood that the appended
claims are intended to cover all such modifications and embodiments
that come within the spirit and scope of the present invention.
* * * * *