Note: Descriptions are shown in the official language in which they were submitted.
CA 02395388 2005-09-06
CONTAINER HAVING~COVER WITH A MULTI-SECTOR SEAL
15 ~ FIELD OF INVENTION
This invention is directed to containers for storage of objects, and more
particularly
containers which are sealable with a cover.
2o BACKGROUND OF THE INVENTION
Sealable containers are known in the art. For example, U.S. Pat. Nos.
3,784,055, iss.
Jan. 8, 1974 to Anderson, and 3,967,756, iss. July 6, 1976 to Barish, disclose
containers
having plug seals. However, plug seals require significant manual manipulation
to effect tight
25 sealing. Unless the user is careful, such a seal may not perimetrically
enclose the aperture
through which the contents of the container are to be accessed. Unless full
perimetric
enclosure is obtained, perishable contents stored in the container may spoil.
Another type of seal is illustrated in commonly assigned U.S. Pat. No.
5,996,882, iss.
Dec. 7, 1999 to Randall. This patent discloses a container having a closure
means activatable
3o by an externally applied force.
One attempt in the art to overcome the problem of having to manipulate a full
perimeter closure, without having visual, tactile, or audible signal that full
sealing has been
obtained, is to use a slider, as illustrated in U.S. Pat. No. 3,660,875, iss.
May 9, 1972 to
Gutman. However, to date, sliders have only been
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2
capable of unidirectional operation. Sliders are not capable of operation in
an XY plane
when used in conjunction with a rigid seal.
U.S. Pat. No. 4,013,214, iss. Mar. 22, 1977 to Hansen et al., discloses a
multiple
plastic container having a cover with a hinged connection to the base. U.S.
Pat. No.
5,046,659, iss. Sept. 9, 1991 to Warburton, discloses a thermoformed plastic
container
1o having a locking lid and base. U.S. Pat. No. 5,577,627, iss. Nov. 26, 1996
to Richie-
Dubler, discloses a thermoformed plastic container having a lid and base with
an integral
hinge. U.S. Pat. 5,339,973, iss. Aug. 23, 1994 to Edwards et al., discloses a
container
having a seal flange comprising a curved surface which interlocks over an arc
of more than
180 degrees.
U.S. Pat. No. 5,667,092, iss. Sept. 16, 1997 to Julius et al., discloses a
container
comprising a cover having a lid tray and peripheral flange. U.S. Pat. No.
5,507,407, iss.
Apr. 16, 1996 to Feer et al., discloses a container lid having a peripheral
flange
dimensioned to receive the rim of a container. The flange terminates at a
skirt having a
lever arm to allow removal of the lid from the container. Likewise, U.S. Pat.
No.
5,377,860, iss. Jan. 3, 1995 to Littlejohn et al., discloses a food container
having a unitary
base and also a unitary lid. U.S. Pat. No. 5,058,761, iss. Oct. 22, 1991 to
Williams,
discloses a reclosable package having a lid and base fusion bonded and
peelably sealed.
U.S. Pat. No. 5,524,990, iss. June 11, 1996 to Buck, discloses a flexible
container
having a flap which closes the container opening. A stiffening element extends
around the
periphery of the flap. However, such a container is neither sealable with a
slider, nor
sealable by manipulating only a limited sector of the stiffening element.
U.S. Pat. No. 4,576,330, iss. Mar. 18, 1986 to Schepp, discloses a tray and
hinged lid
having a locking engagement internal to a flange. U.S. Pat. No. 4,576,307,
iss. Mar. 18,
1986 to Frydenberg, discloses a container having elements held together by a
sliding latch.
3o The sliding latch precludes opening of the container by preventing
transverse movement of
a post/rail combination. U.S. Pat. No. 5,427,266, iss. June 27, 1995 to Yun,
discloses a lid
with a visual seal indication for proper closure. U.S. Pat. No. 5,651,462,
iss. July 29, 1997
to Simonsen et al., discloses a rigid reclosable package having a flexible
cover.
None of the aforementioned references disclose a seal which can be applied by
manipulating a sector of the container subtending an arc less than that of the
seal.
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3
SUMMARY OF THE INVENTION
The invention comprises a container having an aperture to access the contents
of the
container. The aperture is at least partially sealable upon closure with a
cover. The cover
has a seal extending at least partially therearound. The seal subtends a first
sector of the
1o perimeter. The seal is fully activatable by manipulating a second sector of
the perimeter.
The second sector is less than and included within the first sector.
The container may be fully perimetrically sealed by a complementary cover. The
cover is applied to the seal by manipulating only a portion of the seal.
In another execution, the invention comprises a method of sealing contents in
a
container. The method comprises the steps of providing a container having
upstanding
sidewalk, an aperture to access the contents of the container, and a seal
therearound. A
cover is provided which is complementary to the seal. The contents to be
contained are
placed within the container. The cover is placed onto the aperture, so that
the cover is
juxtaposed with the seal and can thereby be engaged. The cover is applied to
the perimetric
2o seal by manipulating a portion thereof, so that the cover is frictionally
engaged by the seal.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective view of a container according to the present
invention,
illustrating the cover in the open position, and an optional slider not
engaging the seal of
the container.
Fig. 2 is a top plan view of the container of Fig. 1 showing the cover in the
closed
condition and the slider having moved from a position which does not engage
the seal to a
position which does engage the seal.
Fig. 3 is a vertical sectional view taken along lines 3-3 of Fig. 2.
DETAILED DESCRIPTION OF THE INVENTION
Fig. 1 depicts a preferred embodiment of a container 10 according to the
present
invention. The container 10 includes a container body preferably unitarily
formed from
sheet material. A cover 12 is included with the container 10 and may be
unitarily formed
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4
s with the container 10. The container 10 further includes a seal 14 for
perimetrically
closing the cover 12 onto the seal 14.
The container 10 is reversibly transformable between two conditions, an open
condition wherein the cover 12 is removed from the container 10 and the
contents of the
container 10 may be accessed. The contents of the container 10 may be accessed
through
an aperture 26. When the cover 12 of the container 10 is in the open position,
contents
may be inserted into or removed from the container 10.
In the other condition, the container 10 is closed and the cover 12 sealed
onto the
container 10. The closed condition prevents unintended removal, and
potentially
tampering with the contents of the container 10. If desired, a lock (not
shown) may be
included to prevent unauthorized access to the container 10 when the cover 12
is closed.
The cover 12 may be generally congruent and substantially coextensive of the
circumference of the container 10 as illustrated. Alternatively, it is to be
understood that
the aperture 26 and cover 12 may be sized and/or shaped to have a geometry
which is
different from that of the aperture 26 of the container 10. While the
illustrated
2o embodiments show a container 10 having a cover 12 which allows access to
the top of the
container 10, it is to be understood a cover 12 which is disposed on one or
more of the
sidewalk 20 or even the bottom of the container 10 may be included. Further,
the
container 10 may have a plurality of covers 12, as desired. For example, the
top of the
container 10 may have two smaller covers 12 rather than one large cover 12 or,
alternatively, the top of the container 10 may have one cover 12 and one or
more
sidewalls 20 of the container 10 have additional covers 12. Further, the
container 10 may
be internally partitioned as desired.
The container 10 is at least partially sealable with the cover 12 when the
cover 12
is in the closed position. In some embodiments, it may be desirable that the
seal 14
3o perimetrically enclose the container 10 when the cover 12 is attached. A
perimetric
closure of the seal 14 may be desired when perishable contents are stored in
the container
10 or dust and contamination are to be kept out of the container 10 for
hygienic purposes.
Alternatively, a partial seal 14 of the container 10 may be desirable when
aspiration of
the container 10 is sought. For example, if the container 10 is to be used for
microwave
heating of food contents, venting of the container 10 may be desired.
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5 The container 10 according to the present invention may be relatively small,
such
that the container 10 may be stored in one's pocket or purse. Such a container
10 may be
useful for storing pills, capsules, etc. Alternatively, the container 10 may
be relatively
large such that the container 10 is sized to fit a flat bed semi-truck. Such a
container 10
may be useful for carrying construction materials, etc. One contemplated use
for the
1o container 10 is to store perishable items such as food.
The container 10 comprises a floor pan 22 and sidewalk 20 projecting outwardly
from the floor pan 22. Preferably, in use, the sidewalk 20 project upwardly
and
terminate at a distal end forming the aperture 26 of the container 10. The
illustrated
embodiment has four sidewalk 20. However, it is to be recognized the invention
is not
so limited. For example, the container 10 may have from three or more walls,
or may be
round, oval, etc.
The cover 12 may be generally flat, as illustrated, or may have a convex
inward or
convex outward orientation, as desired. For certain embodiments, it is
preferred that the
cover 12 be substantially flat so that the container 10 is stackable.
The floor pan 22 defines and lies in a first plane. For the embodiment
illustrated,
the floor pan 22 is defined by the vertices at the four corners of the
upstanding sidewalls
20. The floor pan 22 may be domed convex inwardly to increase strength, as is
known in
the art. Particularly, domed floor pans 22 provide increased strength for
loading by the
contents of the container 10 in a direction normal to the floor pan 22.
Alternatively, the
floor pan 22 may be disposed convex outwardly, although this may be decrease
stability
when the container 10 rests on a horizontal surface. It is to be recognized
and
appreciated that the floor pan 22 may be domed as is known in the art yet
still define a
plane.
The sidewalls 20 are illustrated to be generally perpendicular to and
projecting
outwardly from the floor pan 22. It is to be recognized that sidewalk 20 which
project
outwardly in a non-perpendicular orientation, e.g., such as a divergent
orientation to
provide a greater cross section at the top of the container 10 than at the
floor pan 22, are
known and may be utilized in accordance with the present invention.
Preferably, but not necessarily, the container 10 is formed from a unitary
sheet of
material. By forming the container 10 from a unitary sheet of material, the
presence of
CA 02395388 2005-09-06
6
seal 14 lines within the body of the container 10 is eliminated and pathways
for leakage
are reduced.
Various compositions suitable for constructing the storage containers 10 of
the
present invention include substantially impermeable materials such as
polyvinyl chloride
(PVC), polyvinylidene chloride (PVDC), polyethylene (PE), polypropylene (PP),
aluminum foil, coated (waxed, etc.) and uncoated paper, coated nonwovens etc.,
and
substantially permeable materials such as scrims, meshes, wovens, nonwovens,
or
perforated or porous films, whether predominantly two-dimensional in nature or
formed
into three-dimensional structures. Such materials may comprise a single
composition or
layer or may be a composite structure of multiple materials, including a
substrate material
utilized as a carrier for a substance. Materials found suitable for use in
accordance with
the present invention include a low density polyethylene film, 10 mil (0.25
millimeters)
thickness, commercially available from Chevron under the manufacturer's
designation
PE1122 or syndiotactic polypropylene available from Fina Corp. under the
designation
EOD96-28 of 20 mil (0.5 millimeters) thickness. Further suitable materials
include a
polyethylene/polypropylene blend. Wood and metal may be used for larger size
containers 10.
Optionally, the container 10 may be reversibly erectable and collapsible.
Particularly, such a container 10 is reversibly transformable between
collapsed and
erected conditions. A collapsible container 10 may be made by having a
plurality of the
sidewalls 20 interconnected and projecting outwardly from the floor pan 22. At
least one
of the sidewalls ZO may have a hinge line disposed substantially parallel to
the plane of
the floor pan 22. The hinge line divides the sidewall 20 into upper and lower
portions,
each of which is articulable about the hinge line when the container 10 is
transformed
between the collapsed and erected conditions. Preferably, each of the
sidewalls 20 has a
hinge line and/or an optional gusset to effect collapse and erection. Another
form of
collapsible container 10 is illustrated in the aforementioned U.S. Pat.
No. 5,996,882, iss. Dec. 7, 1999 to Randall. If it is desired to make a
resiliently
deformable container 10, the container 10 may be made according to the
teachings of
commonly assigned U.S. Pat. No. 5,379,897, iss. Jan. 10, 1995 to Muckenfuhs et
al.
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7
If desired, the container 10 may further be selectively reinforceable,
particularly if
the sidewalis 20 of the container 10 are collapsible. The sidewalk 20 may be
reinforceable with an upstanding strut removable from the sidewalk 20 without
separation from the container 10. The struts is transformable between a first
position
providing reinforcement to the sidewalk 20 and the second position wherein the
strut
to does not provide reinforcement to the sidewall 20. Such a strut may be
proximally
articulable and hingedly attached to the container 10 at the juncture of the
floor pan 22
and respective sidewall 20.
The reinforcement may further comprise a floor pan 22 support. The floor pan
22
support spans the floor pan 22, and preferably the major axis thereof. If
desired, the floor
pan 22 support may be unitarily formed with one or more struts which
selectively
reinforce the sidewalk 20.
Referring to Fig. 1, and examining the aperture 26, the seal 14 and the cover
12 of
the container 10 in more detail, the seal 14 may be disposed on a flange 52.
The flange
52 is circumjacent the aperture 26 of the container 10, although it is to be
understood that
2o in a less preferred embodiment, the seal 14 may be internal to the aperture
26 of the
container 10.
The seal 14 is preferably rigid, even though the sidewalk 20 may be flaccid,
self
supporting, and/or reversibly collapsible and erectable as noted above. By
rigid, it is
meant that the seal 14, even if compliant, has vector components extending in
both the X
and Y directions when the container 10 is in its natural, unconstrained state.
Thus, when
the container 10 is empty, the seal 14 extends in both the X and Y directions.
Further, the
aperture 26 of such a container 10 has the same geometry whether the container
10 is
empty or filled under normal usage conditions.
A seal 14 is considered to be applied and operable when the cover 12 is in the
3o closed position and the seal 14 resists and contains a static hydraulic
pressure of at least
2.5 centimeters of distilled water at 20°C. Such a seal 14 may be
tested by filling the
container 10 to the appropriate depth, applying the seal 14, then turning the
container 10
on its side so that the distilled water is applied at a height of 2.5
centimeters above the
seal 14. If no leakage occurs within 15 seconds, the seal 14 is considered to
be applied
and operable.
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8
The seal I4 defines an XY plane and a Z-direction orthogonal thereto. The seal
14 extends in at least two directions, such that the seal 14 defines a path
having multiple
vector components in each of the X and Y directions. The seal 14 path may be
rectilinear, curvilinear, or a combination thereof.
In one embodiment, the seal 14 may be disposed in two mutually perpendicular
1 o directions, one substantially parallel to the X direction and the other
substantially parallel
to the Y direction. Such directions may be congruent or even coincident the
top edge of
the sidewalls 20 of the container 10. If so, the seal 14 defines a vertex
having a minimum
radius of curvature determinable by the specific type of seal 14 to be
employed, as
discussed below. The vertex defines a Z-direction axis ~ perpendicular to the
aforementioned XY plane. It is to be noted that the XY plane so defined may
be, and is
preferably substantially parallel to the plane defined by the floor pan 22 of
the container
10, although skewed plane relationships are specifically contemplated. The
seal 14 may
lie within the XY plane, and the cover 12 removable in a direction having a Z-
direction
vector component. It is to be recognized that the cover 12 may be articulable
as shown or
2o translatable in the axis of the vertex. In contrast to the slider 60 type
geometries
illustrated in the aforementioned U.S. Pat. No. 3,660,875, iss. May 9,
1972 to Gutman, the seal 14 of the present invention is orthogonal to the axis
of the
vertex.
If the slider 60 is used, activation of the slider 60 in the closing direction
compresses the seal 14. The seal 14 may be thought of as having a longitudinal
axis
within the XY plane of the path of the seal 14. The slider 60 compresses the
seal 14 in a
direction substantially perpendicular to the longitudinal axis.
If it is desired to remove the cover 12 from the container 10 without a
hingeable
articulation as illustrated, guide rails may be joined to and project from the
internal or
3o external surfaces of the sidewalls 20 of the container 10. The cover 12 may
be joined to
the guide rails. The guide rails may have slots extending perpendicular to the
XY plane
of the seal 14. The cover 12 is thus translatable perpendicular to the XY
plane by
movement along the guide rails.
Whether an articulable cover 12 is selected, or a cover 12 translatably
removable
3s from the aperture 26 of the container 10 is selected, in either case, the
cover I2 may not
necessarily separate from the container 10 even though it is removable
therefrom. By not
CA 02395388 2005-09-06
9
being separable from the container 10, it is meant that the cover I2 cannot be
permanently displaced apart from the container 10 without tearing or gross
deformation
of the material comprising either the container 10, the cover 12, or any
members
connecting or adjoining the container IO to the cover 12. By not separating
the cover 12
from the container 10, the benefit occurs that the cover 12 does not become
misplaced,
lost, or intermixed with covers 12 from like-sized containers 10 having
different hygienic
or sanitary requirements.
Referring to Fig. 3, the seal 14 may comprise any type of reusable mechanism
known in the art. Suitable seals 14 include fin seals 14, adhesive seals 14,
cohesive seals
14, selectively activatable adhesives as illustrated by commonly assigned U.S.
Pat. Nos.
i5 5,662,758, iss. Oct. 2, 1997 in the names of Hamilton et al., 5,871,067,
iss. Feb. 16,
1999 in the names of Hamilton et al., U.S. Patent No. 5,965,235 iss. Oct. 12,
1999 in the
name of McGuire et al., and seals 14 having a friction fit or a compression
fit, as
illustrated. By reusable, it is meant that the cover 12 of the container 10
may be
reversibly transformed between each of the open and closed positions at least
two times
and still functionally seal 14 the container 10.
positions at least two times and still functionally seal 14 the container 10.
One suitable type of seal 14, as illustrated, utilizes complementary
projections S4
and recesses 56. It is to be understood that the illustrated embodiment
utilizes a flange 52
extending in the XY plane. The flange S2 is circumjacent the aperture 26 of
the container
10. The flange 52 has a projection 54 extending normal to the XY plane. The
cover 12
has a recess 56 extending normal to the XY plane and complementary with the
projection
S4. The projection 54 is inserted into the recess 56, providing a compression
seal 14
which extends at least partially, and preferably perimetrically around the
aperture 26 of
the container 10.
3o It is to be understood by one of ordinary skill that this disposition may
be
reversed, so that the recess 56 is disposed in the flange 52 of the container
10. Further,
the cover 12 of the container 10 may also have a flange 52 also extending in
the XY
plane.
If desired, the container 10 may be sealable with an optional slider 60. As
used
herein, a slider 60 is an apparatus which moves along the aforementioned path
of the seal
14 to open, close, or preferably open and close the seal 14.
CA 02395388 2005-09-06
5 Referring to Fig. 2, if the optional slider 60 is included with the
container 10 and
cover 12, the slider 60 may be movable in a path juxtaposed with the perimeter
of the
aperture 26. It is to be understood that the seal 14 need not be coincident or
juxtaposed
with the perimeter of the aperture 26 of the container 10.
The slider 60 may activate the seal 14, whereby the slider 60 applies the seal
14
1o when moved in a first direction and releases the seal 14 when moved in the
opposite
direction. Thus, activation of the seal 14 includes either application of the
seal 14, such
as desired for closing the container 10, or release of the seal 14, such as
desired for
opening the container 10, or both.
The slider 60 may be disposed in a track 62, thus distinguishing the slider 60
of
the present invention from and insuring the slider 60 of the present invention
does not
include an ordinary zipper. The track 62 is spaced apart from the seal 14. In
the
illustrated embodiments, the track 62 is outboard of the seal 14, it being
understood the
track 62 could be inboard of the seal 14 as well. The track 62 is in operative
association
with the seal 14, whereby the slider 60 can be disposed in the track 62, and
still activate
2o the seal 14 in either or both of the apply and release directions. The
track 62 is preferably
congruent with the seal 14, as illustrated.
The slider 60 is preferably frustroconically shaped. The inside of the slider
60
applies the seal 14 upon activation in the closing direction. The outside of
the slider 60
releases the seal 14 upon activation in the opening direction.
It is to be recognized that there are various configurations comprising a seal
14/track 62 combination. But, generally, any geometry having a friction or
compression
fit of the seal 14 against parent material of either the container 10 or cover
12 while also
providing a guide surface for the slider 60 will be suitable. It is to be
recognized that the
guide surface, and hence the track 62, will be spaced apart from the seal 14.
The track 62 may, and preferably does, further comprise one or more auxiliary
tracks 64. The auxiliary tracks 64 are defined as those portions of the track
62 which are
not operatively juxtaposed with the seal 14. The optional slider 60 may ride
in the track
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62 until it no longer engages the seal 14, then enters the auxiliary track 64.
When the
slider 60 is disposed in the auxiliary track 64, the slider 60 does not
engage, and thus
cannot activate, the seal 14. The auxiliary track 64 may be disposed radially
outward of
the seal 14, as illustrated, or, if the track 62 is inboard of the seal 14,
may be disposed
radially inward of the seal 14. Preferably, the auxiliary track 64 does not
cross the seal
14, otherwise a perimetric seal will not occur, unless engagement occurs at
the top of the
seal 14.
In the external track 62 embodiment, the container 10 is perimetrically
enclosable
by the seal 14, a feature not obtainable in the prior art relating to sliders
60. The seal 14
is circumferentially applied and released, with or without the optional slider
60, around
the perimeter of the aperture 26. The seal 14 may be applied, at least
partially around the
perimeter of the aperture 26, by activation, manually or with a slider 60,
beginning at a
first circumferential position and continuing in serial fashion around the
container 10 to a
second position circumferentially spaced apart from the first position. The
cover 12 is
attached to the container 10 at yet a third circumferential position. The
third position is
2o circumferentially juxtaposed with at least one of the first position and
second positions,
and preferably both such positions, as illustrated.
Referring still to Fig. 2, two auxiliary tracks 64 are shown. The cover 12 is
hingedly attached to the container 10 at the third position. The auxiliary
tracks 64
circumferentially bound the hinged attachment of the cover 12 to the container
10. Thus,
preferably, the container 10 has two auxiliary tracks 64 as illustrated. With
this
arrangement, the slider 60 can be parked in one auxiliary track 64 upon
translation in the
opening direction, so that the slider 60 does not interfere with opening of or
access to the
contents of the container 10. Likewise, the slider 60 can be parked in the
other auxiliary
track 64 upon activation of the seal 14 in the closing direction. It is, of
course,
3o recognized that the slider 60 may be parked in an auxiliary track 64 at a
position not
juxtaposed with the hinge or other means for attaching the cover 12 to the
container 10.
In the auxiliary track 64, the terminal end 66 of the slider 60 need only be
spaced
apart from the seal 14 a distance sufficient to allow the slider 60 to clear
the seal 14, so
that the cover 12 may be opened or closed as desired without interference from
the slider
60. For the embodiments illustrated, a slider 60 having a width in the radial
direction, the
terminal ends 66 of the auxiliary tracks 64 are spaced outwardly, in the
radial direction,
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12
from the seal 14 a distance sufficient to accommodate the width of the seal 14
and the
width of the slider 60.
It is not necessary that the auxiliary track 64 have a terminal end 66 which
predisposes the slider 60 to park in a particular position. If desired, the
slider 60 may be
removed from the auxiliary track 64, and thus separated from the seal 14 and
container
l0 10. Such an arrangement may be useful where it is desired to independently
clean the
slider 60, providing the slider 60 is not lost or misused.
In an alternative embodiment (not shown), the slider 60 may be parked in a
position juxtaposed and even coincident with that of the seal 14. In such an
arrangement,
the cover 12 has a cut-out which allows the cover 12 to clear the slider 60 so
that the
cover 12 may be opened without interference from the slider 60.
In operation, the container 10 is at least partially and preferably
perimetrically
sealable upon closure by the cover 12. The seal 14 subtends a first sector 70
of the
perimeter. The first sector 70 preferably subtends at least 270 degrees, more
preferably
subtends 360 degrees. The seal 14 may be fully applied throughout the first
sector 70, by
2o activation in the closing direction, of a second sector 72 of the seal 14.
The second sector
72 is less than and included within the first sector 70. The second sector 72
preferably
subtends an angle of 260 to 360 degrees, and preferably at least 290 degrees.
As
illustrated, the hinge may be disposed circumferentially outside of the second
sector 72.
Thus, the slider 60, and any other manual manipulation or activation of the
seal 14, does
not intercept the hinge.
If desired, the container 10 and cover 12 may comprise two or more seals 14
disposed in series. Such seals 14 may be radially offset so that multiple
occurrences of
leakage through the seal 14 are required before the cover 12 is breached.
Alternatively,
an individual seal 14 may comprise two or more sliders 60. In such an
arrangement, each
3o slider 60 subtends a portion of the first sector 70.
