Note: Descriptions are shown in the official language in which they were submitted.
CA 02456605 2004-02-02
RECLOSEABLE ZIPPER AND BAG EMPL(aYING SAME
BACKGROUND Oi: THE INVENTIQN
Field of the Invention
[0001] The present invention relates generally to the packaging art, and more
particularly to a reclosable zipper of a type used to close a mouth of a bag.
Description of the Related Art
[0002] Packaging materials with reclosable plastic zippers that are opened by
peeling and resealed by pressing are widely used as packaging bags for
granular,
powdery and other solid materials mainly due to their light weight and
relatively low
cost. Although there are a wide variety of reclosable plastic zippers used in
packaging materials, most of them are rendered inoperable if the packaged
material
comes in contact with the zipper- as it is inserted into or removed from the
bag.
Particularly, granular or powdery materials have a tendency to clog the mating
portions of the zipper, rendering the zipper inoperable. The limitations
specifically
minimized andlor eliminated by the present invention include the inoperability
of a
reclosable zipper due to the insertion or removal of granular and powdery
packaged
materials from a packaging bag.
SUMMARY OF THE INVENTIOLV
[0003] According to the present invention, a reclosable zipper is provided
that
includes a female portion having a first base that defines a continuous
groove, and a
male portion that includes a second base and a male rib. The male nb extends
outwardly from the second base for insertion into the continuous groove of the
female
portion and is locked therein when the male and female portions are pressed
together.
A protective flange extends outwardly from at least one of the first and
second bases
proximate the male rib or continuous groove of the reclosable zipper.
[0004] In one embodiment of the present invention, the female portion includes
a
pair of female hooks that extend outwardly from the first base, wherein the
pair of
female hooks define the continuous groove. One of the female hooks extends
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outwardly from the first base a greater distance that the other female hook.
The
protective flange extends outwardly from the second base proximate the male
rib.
[000S] When the zipper is employed in a packaging bag, such as a reclosable
plastic bag, the longer female hook and protective flange deflect a granular
or
powdery packaged material away from the male and female portions, which
inhibits
clogging of the male and female portions and allows the zipper to be closed
without
interference.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The features and inventive aspects of the present invention will become
more apparent upon reading the following detailed description, claims, and
drawings,
of which the following is a brief description
[0007] FIG. I is a cross-sectional view of a reclosable zipper according to a
prefeiTed embodiment of the present invention.
[000$] FIG. 2 is a cross-sectional view of a reclosable zipper according to
another
embodiment of the present invention.
[0009] FIG. 3 is a cross-sectional view of a reclosable zipper according to
another
embodiment of the present invention.
j0010] FIG. 4 is a cross-sectional view of a recIosable zipper according to
another
embodiment of the present invention.
[0011] FIG. 5 is a cross-sectional view of the reclosable zipper of FIG. I,
showing
the male and female portions of the zipper molded into the side walls of a
packaging
bag.
[0012] FIG. 6 is a cross-sectional view of a packaging bag employing the
reclosable zipper of FIG. 1, showing insertion of a packaged material into the
bag.
[0013) FIG. 7 is a cross-sectional view of the packaging bag of FIG. 6,
showing
removal of the packaged material from the bag.
[00I4] FIG. 8 is a cross-sectional view of a packaging bag employing the
reclosable zipper of FIG. 3, showing insertion of a packaged material into the
bag.
[OOIS] FIG. 9 is a cross-sectional view of the packaging bag of FIG. 8,
showing
removal of the packaged material from the bag.
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DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0U16] Referring now to the drawings, preferred embodiments of the present
invention are shown in detail. Referring to FIG. l, there is shown a
reclosable zipper
10 that includes a female portion 12 and a male portion 14. Zipper 10 is
preferably
manufactured of a lightweight, flexible plastic, such as polyethylene and the
like, by
extrusion, molding or other known processes for forming plastic and other
polymeric
materials.
[0017] Female portion 12 is defined by a first base 16 having a pair of female
hooks 18, 20 that extend outwardly therefrom. Female hooks 18, 20
cooperatively
define an elongated channel or groove 22. Each of female hooks 18, 20 is
provided
with a catch 24 that extends inwardly toward groove 22. As shown in FIG. l,
and for
reasons that will be described in detail below, one of female hooks 18 extends
outwardly from first base 16 a greater distance than the other female hook 20.
[0018) Male portion 14 is defined by a second base 2G having a male rib 28
that
extends outwardly therefrom. Male rib 28 is provided with a head portion 30
that
cooperatively engages catches 24 on female hooks 18, 20 to retain male iib 28
in
groove 22 once it is inserted therein. Because male rib 28 must be pressed
into
groove 22, it is prefen-ed, but not required, that male rib 28 be more rigid
than female
hooks 18, 20. Similarly, for the same reasons, it is also preferred, but not
required,
that female hooks 18, 20 be more elastic than male rib 28 to allow them to
flex and
accommodate insertion of male rib 28 therebetween. However, it will be
appreciated
that a single material may be employed to manufacture zipper 10, the
properties of
this material exhibiting a balance between the rigidity preferred for male rib
28 and
the elasticity preferred for female hooks 18, 20.
[UU19] For convenience of description, reclosable zipper 10 is described as
having
a male nib 28 and a female groove 22, wherein a head portion 30 of the male
rib 28 is
received by the female hooks 18, 20 of the cooperating female groove 22, but
it will
be understood and appreciated by those of skill in the art that certain
principles of the
invention may apply to other modified forms of the zipper closure. Similarly,
it will
be appreciated that the claims are not limited to the specific form of the rib
and
groove illustrated in the drawings and described herein.
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[0020] As illustrated in the embodiment of FIG. I, male portion 14 is also
provided with a protective flange 32 that extends outwardly from second base
26.
Protective flange 32 is provided proximate male rib 28, but not too close as
to inhibit
insertion of male rib 28 into groove 22. Protective flange 32 extends from
second
base 26 at least the same distance male lib 28 extends from second base 26 and
preferably slightly farther, for reasons that will be detailed below.
Protective flange
32 may be disposed substantially perpendicular to second base 26, as shown in
FIG.
1, or at least a portion if not all of protective flange 32 may be disposed at
some angle
relative to second base 26.
[0021] A support flange 34 also extends from second base 26 to support the
portion of first base 16 proximate female hooks 18, 20. Support flange 34
cooperates
with protective flange 32 to support male rib 28 in groove 22, and
functionally
inhibits unintentional separation of male and female portions 12, 14.
[0022] FIG. 2 illustrates another embodiment of the present invention. In this
embodiment, a zipper IO' is provided that includes a female portion I2' having
a first
base 16' and a male portion 14' having a second base 26'. Unlike zipper 10
described
above, both first and second bases 16', 26' include a protective flange 32A
and 32B,
respectively. Also, unlike the female portion 12 of zipper 10 described above,
female
portion 12' of zipper 10' may include female hooks 18', 20' that are
substantially the
same length.
[0023] FIG. 3 illustrates another embodiment of the present invention. In this
embodiment, a zipper 10" is provided that includes a female portion 12" having
a first
base 1.6" and a male portion I4" having a second base 26". Unlike zippers 10,
IO'
described above, second base 26" includes a pair of protective flanges 32C,
32D,
which are positioned on either side of male rib 28". Additionally, first base
16"
includes a protective flange 32E that is longer than protective flange 32D,
Alternatively, as shown in FIG. 4, protective flange 32E may be shorter than
protective flange 32D.
[0024] Refen~ing to FIG. 5, first and second bases 16, 26 are each formed with
a
pair of elongated flanges 37 and 39 that extend away from first and second
bases 16,
26. Flanges 37, 39 provide additional surface area to secure zipper 10 to a
packaging
bag. Flanges 37, 39 of zipper 10 may be secured to the packaging bag by heat
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welding, ultrasonic welding or other known process for securing one polymeric
material to another. Although not illustrated, it will be appreciated that any
of the
embodiments shown in FIGS. 2-4 may also be integrally formed with flanges 37,
39
in a similar manner.
[0025] FIGS. 6 and 7 illustrate a flexible bag 44 of lightweight plastic, such
as
polyethylene or like polymer, having a reclosable zipper 10 according to the
principles of the present invention. The plastic used as the material for
zipper IO may
be the same type or a different type of plastic used for the main body of the
bag as
Tang as it exhibits the material properties need for zipper 10 to function.
Preferably,
to the portion of the zipper which should exhibit high ugidity is employed a
plastic
having a high rigidity, while to the portion thereof which should exhibit
elasticity is
employed a plastic exhibiting the required elastic properties. However, it
will be
appreciated that a single material may be employed to manufacture bag 44, the
properties of this material exhibiting a balance between the properties
preferred for
the respective portions of the zipper.
[0026] Bag 44 includes a pair of opposing side walls 40, 42 that define an
openable mouth 46. Mouth 46 includes the elongate reclosable zipper 10
extending
across the inside thereof. Female portion 12 and male portion 14 of zipper 10
are
shown in FIGS. 6 and 7 as being non-interlocked.
[0027) In FIGS. 6 and 7, the longer female hook 18 and protective flange 32
are
positioned inwardly of groove 22 and male rib 28, respectively, toward the
inside of
bag 44. To fill bag 44 with a packaged material 4$, as shown in FIG. 6, an end
50 of
a fill tube 52 is inserted into bag 44 past protective flange 32 and the
longer female
hook 18. Thus, as bag 44 is filled, none of the packaged material 48 comes
into
contact with male rib 28 and female groove 22 of zipper 10, allowing zipper 10
to be
closed without interference.
[0028] When bag 44 is emptied, as shown in FIG. 7, protective flange 32 and
the
longer female hook 18 deflect the packaged material 48 away from the male and
femaie portions of zipper 10. Specifically, because protective flange 32 is
longer than
male rib 28, the packaged material 48 is completely deflected away from male
rib 28.
Similarly, because female hook 18 is longer than female hook 20, the packaged
material 38 is completely deflected away from groove 22. Thus, as bag 44 is
emptied,
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none of the packaged material 48 becomes attached to or clogs male rib 28 or
female
groove 22, allowing zipper 10 to be re-closed without interference.
[0029] Alternatively, although not illustrated, each portion of zipper 10 may
be
invested such that protective flange 32 and the longer female hook 18 face the
opening or mouth 46 or outside of bag 44. This configuration would be useful
where
the bag is emptied using a suction tube that is inserted past male rib 28 and
female
groove 22, and is filled in a manner that would normally allow the packaged
material
to contact male nib 28 and female groove 22, but far the protective flange 32
and the
longer female hook 18 deflecting the packaged material away from these
features,
[0030] The embodiments illustrated in FIGS. 2 and 3 are also employable in bag
44 and function in manner similar to the embodiment shown in FIGS. 1, 6 and 7
to
deflect a packaged material away from male rib 28 and female groove 22. For
example, FIGS. 8 and 9 illustrate a bag 44" employing the zipper 10" shown in
FIG.
3. Unlike the embodiment shown in FIGS. l, 6 and 7, no fill tube 52 is
required to
insert the packaged material 48" into bag 44". Instead, as shown in FIG. 8,
protective
flanges 32D and 32E deflect the packaged material 48" away from male rib 28"
and
female groove 22". Thus, as bag 44" is filled, none of the packaged material
48"
comes into contact with male rib 28" or female groove 22", allowing zipper 10"
to be
closed without interference.
[0031) When bag 44" is emptied, as shown in FIG. 9, protective flange 32C and
the longer female hook 18" deflect the packaged material 48" away from male
rib 28"
and female groove 22". Thus, as bag is emptied, none of the packaged material
48"
becomes attached to or clogs male rib 28" or female groove 22", allowing
zipper 10"
to be re-closed without interference.
[0032] Although certain preferred embodiments of the present invention have
been described, the invention is not limited to the illustrations described
and shown
herein, which are deemed to be merely illustrative of the best modes of
carrying out
the invention. A person of ordinary skill in the art will realize that certain
modifications and variations will come within the teachings of this invention
and that
such variations and modifications are within its spirit and the scope as
defined by the
claims.
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