Note: Descriptions are shown in the official language in which they were submitted.
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SYSTEM AND METHOD FOR DISPOSING WASTE
PACKAGES SUCH AS DIAPERS
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] This invention relates broadly to the field of household and
institutional waste
disposal systems and processes, and more specifically to diaper pail systems
and methods for
hygienically holding and packaging particularly unsanitary and odiferous
waste, such as used
= diapers, for eventual disposal.
2. Description of the Related Technology
[0002] Since the introduction of disposable diapers several decades ago,
parents and
caregivers have struggled with the problem of how to hold unsanitary,
odiferous waste
packages such as used disposable diapers and wipes within an infant's changing
room for
eventual final disposal with a waste management service. Institutions, such as
hospitals and
day care centers have faced a similar problem.
[0003] Holding such waste packages in ordinary trash cans is problematic,
even when a lid
is used, because a substantial amount of odor can and will escape into the
surrounding room
when the lid is removed, and again when the lid is replaced. In order to
address this problem,
diaper disposal systems have been developed that are designed to encase the
waste package
within a plastic barrier material.
[0004] One such system has been marketed under the trademark DIAPER GENIES.
The
original DIAPER GENIES system uses a long, continuous length of plastic tubing
that is
dispensed from an annular space within a tube-holding cartridge that has a
central opening.
The consumer prepares the system for use by closing one end of the tubing with
a knot and
pushing the knotted end through the central opening. He or she then inserts a
waste package
through the central opening, and the cartridge is rotated in order to create a
twist seal in the
tubing above the waste package. Additional tubing is dispensed as the
cartridge is rotated.
The process may be repeated until the storage compartment in the container is
full. When this
occurs, the consumer must physically cut the upper end of the tube and tie
another knot at the
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open end of the tube. Such systems yield an awkward chain of individual waste
packets
within compartments that are defined in the long tube by a multiplicity of
twisted portions.
[0005] Such a system can be relatively complicated for the uninitiated,
requiring the parent
or caregiver to tie knots at both ends of the tube and to thread the tube
through the central
hole when installing a tubing cartridge. While this may not be a problem for
an experienced
individual, it could cause problems for an inexperienced caregiver, such as a
young babysitter
or grandparent. Using such a system could also be problematic for a disabled
individual,
especially a person who has vision problems or who lacks manual dexterity.
Removing the
long chain of waste packages from the storage space of such a device can also
be
cumbersome. Such systems are also uneconomical due to the amount of plastic
tubing
material used per waste package.
[0006] Another version of the DIAPER GENIES system also requires the parent or
caregiver to pull a measured length of plastic tubing out of a cassette and to
tie a knot at the
end of the tubing. The knotted portion must then be pushed downwardly through
a pair of
spring-loaded jaws into a lower portion of the unit. The parent or caregiver
will then insert
used disposable diapers that have been tightly rolled through a central
opening in the cartridge
downwardly into the knotted tube through a portion of the tube that is clamped
by the spring-
loaded jaws. When the lower portion of the tube is full of used diapers, the
parent or
caregiver will use an integrated cutter mechanism to cut the upper portion of
the tube and
close it with a knot. The tube having knots at both ends is then pulled out of
the unit and
thrown away.
[0007] Unfortunately, the pressure that is created by the spring-loaded
jaws in the second
version of the DIAPER GENIES system does not always form an effective odor
seal. When
a diaper is being pushed downwardly against the bias of the jaws, the jaws are
forced open,
causing open communication between the odiferous air in the lower portion of
the tube and
the surrounding room. Accordingly, when a new waste package is being placed in
the tube,
the parent or caregiver can be exposed to a noticeable amount of odor.
Inserting a waste
package into such a system can also be an uncomfortable experience for a
parent or caregiver,
because his or her hand may become temporarily trapped between the spring-
loaded jaws.
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[0008] In both versions of the DIAPER GENIE system, both ends of the tubing
are tied
with a knot rather than sealed, which under certain circumstances can lead to
leakage of liquid
waste onto the floor or carpet, the unit or the clothing of a parent or
caregiver.
[0009] Another type of waste disposal system has been invented by Mr. David
Stravitz
and is disclosed in United States Patents 6,612,099, 6,804,930, 6,851,251,
7,114,314, and
7,146,785. These systems may include a container that defines a waste
receiving chamber, an
insert defining a cavity for receiving a pack of flexible tubing and an inner
lid that is
connected to the container for covering or exposing an open top of the insert.
The inner lid
and the insert define a dispensing opening through which the tubing passes
during use of the
waste disposal system. An outer lid, which is optionally pivotally connected
to the container,
is movable between a position in which the waste receiving chamber is
accessible and a
position in which the waste receiving chamber is covered. A retention
mechanism holds the
waste package while a rotation mechanism causes rotation of the retention
mechanism
relative to the insert to cause a twist to be formed above a waste package
when held by the
retention mechanism. This encapsulates the waste package in the tubing.
[00010] Mr. Stravitz has more recently invented new diaper disposal systems in
which a
single use diaper pail bag has an upper end that is fixed between two
different portions of a
rigid frame that is mounted so as to be rotationally fixed with respect to the
housing of the
unit. In these systems, which are described in pending United States Patent
Applications
Serial Numbers 12/172,175, 12/172,758 and 12/172,793, a rotatable member
having a
plurality of resilient, inwardly directed fingers is used to engage an
intermediate portion of the
single use bag in order to create a twist between upper and lower portions of
the bag in order
to form an odor seal. While certain principles within this system are believed
to have
considerable promise, there has been a need for additional innovation in order
to provide a
diaper disposal system of commercial quality that has the convenience,
functionality and
durability to be the best diaper disposal system ever developed.
[00011] A need has existed for an improved diaper disposal system that is more
convenient
to load and to use, that utilizes space in a more efficient manner and that
reduces the potential
for odor and liquid leakage in comparison to conventional commercial diaper
disposal
systems.
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SUMMARY OF THE INVENTION
[00012] Accordingly, it is an object of the invention to provide an improved
diaper disposal
system that is more convenient to load and to use, that utilizes space in a
more efficient
manner and that reduces the potential for odor and liquid leakage in
comparison to
conventional commercial diaper disposal systems.
[00013] In order to achieve the above and other objects of the invention, a
diaper pail
assembly according to a first aspect of the invention includes a housing, the
housing having a
plurality of recesses; a bag unit having a bag frame and a flexible bag, the
bag frame being
releasably mounted to the housing so as to be prevented from rotating with
respect to the
housing, wherein the bag frame has a plurality of tabs that are respectively
positioned within
the plurality of recesses.
[00014] A diaper pail assembly according to a second aspect of the invention
includes a
housing, the housing having at least one recess; a bag unit having a bag frame
and a flexible
bag, the bag frame being releasably mounted to the housing so as to be
prevented from
rotating with respect to the housing, wherein the bag frame has at least one
tab that is
positioned within the recess; and wherein the housing further comprises a
locking mechanism
for releasably locking the tab within said recess.
[00015] According to another aspect of the invention, a diaper pail assembly
includes a
housing; a bag unit having a bag frame and a flexible bag, the bag frame
having a lower
surface and being releasably mounted to the housing so as not to rotate with
respect to the
housing; and wherein the housing is constructed and arranged to permit a user
to lift the bag
frame from said housing by contacting the lower surface.
[00016] A diaper pail assembly according to another aspect of the invention
includes a
housing; a flexible bag releasably mounted to the housing so as not to rotate
with respect to
the housing; and a rotatable member for twisting a portion of the bag, the
rotatable member
comprising a plurality of flexible, inwardly extending fingers, and wherein a
bag contact
portion of the fingers has a kinetic frictional coefficient with respect to
like material that is
substantially within a range of about 0.37 to about 0.67.
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[00017] A diaper pail assembly according to another aspect of the invention
includes a
housing; a flexible bag releasably mounted to the housing so as not to rotate
with respect to
the housing; and a rotatable member for twisting a portion of the bag, the
rotatable member
comprising a plurality of inwardly extending fingers that are fabricated from
an elastomeric
material, and wherein said elastomeric material has a hardness that is within
a range of about
60 Shore A to about 120 Shore A.
[00018] A diaper pail assembly according to another aspect of the invention
includes a
housing; a flexible bag releasably mounted to the housing so as not to rotate
with respect to
the housing, the external surface of the flexible bag having a kinetic
frictional coefficient with
respect to like material that is within a range of about 0.12 to about 0.47;
and a rotatable
member for twisting a portion of the bag, the rotatable member comprising a
plurality of
inwardly extending fingers having a bag contact surface.
[00019] A diaper pail assembly according to another aspect of the invention
includes a
housing; a bag releasably mounted to the housing so as not to rotate with
respect to the
housing; and a rotatable member for twisting a portion of the bag, the
rotatable member
comprising a plurality of flexible, inwardly extending fingers and a
corresponding plurality of
spaces defined between the fingers, and wherein at least one of the spaces has
a first width at
a first location and a second width at a second location, and wherein the
first width is greater
than the second width.
[00020] A diaper pail assembly according to another aspect of the invention
includes a
housing; a bag releasably mounted to the housing so as not to rotate with
respect to the
housing; and a rotatable member for twisting a portion of the bag, the
rotatable member
comprising a plurality of flexible, inwardly extending fingers, the fingers
being constructed
and arranged to define a central opening having a minimum diameter when the
fingers are in
an unstressed position, and wherein the minimum diameter is within a range of
about 3 mm to
about 13 mm.
[00021] A diaper pail assembly according to another aspect of the invention
includes a
housing; a bag having a bag frame, the bag frame being releasably mounted to
said housing so
as not to rotate with respect to the housing; a rotatable member for twisting
a portion of the
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bag, and wherein the rotatable member comprises a support member for
supporting the bag
frame.
[00022] A diaper pail assembly according to another aspect of the invention
includes a
housing; a bag holder for holding a bag; a bottom surface for supporting the
bag, wherein said
bottom surface comprises a curved concave portion for aligning and centering
the bag.
[00023] A diaper pail assembly according to another aspect of the invention
includes a
housing; a lid mounted to the housing; a bag; a rotatable member for effecting
twisting of the
flexible bag; and a transmission mechanism for rotating the rotating member
when the lid is
closed, and wherein the transmission member includes a clutch mechanism that
is constructed
and arranged to disengage when a predetermined amount of force within said
transmission
mechanism is exceeded.
[00024] A diaper pail bag according to another aspect of the invention
includes a flexible
bag; a frame attached to the flexible bag, the frame having a hinge defined
therein; and a
reinforcing element for strengthening the attachment between the flexible bag
and the frame
at a location proximate to the hinge.
[00025] A diaper pail bag according to another aspect of the invention
includes a flexible
bag; a frame attached to the flexible bag, the frame having a hinge defined
therein; wherein
the frame has a lower surface, and wherein the flexible bag is bonded to the
lower surface.
[00026] A diaper pail bag according to another aspect of the invention
includes a flexible
bag, at least a portion of the flexible bag being pleated; and a frame
attached to the flexible
bag.
[00027] A diaper pail bag according to another aspect of the invention
includes a flexible
bag; and a frame attached to the flexible bag, the frame having a hinge
defined therein
permitting the frame to be moved between open and closed positions, and a
plurality of
outwardly extending registration projections.
[00028] A method of storing used diapers for disposal according to another
aspect of the
invention includes steps of installing a pleated flexible bag having a first
diameter at a first
upper portion and a second diameter that is greater than the first diameter at
a second lower
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portion into a diaper disposal system so that said second, lower portion of
said pleated
flexible bag is located within a storage space of the diaper disposal system;
placing at least
one used diaper within the pleated flexible bag; and removing the pleated
flexible bag from
the diaper disposal system.
[00029] A method of opening a diaper pail bag assembly according to another
aspect of the
invention includes steps of providing a diaper pail bag assembly including a
flexible bag
portion and a hinged frame portion that is attached to the flexible bag
portion, the step of
providing a diaper pail bag assembly being performed by providing the diaper
pail bag
assembly with the hinged frame portion being in a closed, folded position; and
manipulating
at least two tab members that are integral with the hinged frame portion in
order to move the
hinged frame portion out of the closed position.
[00030] A method of using a diaper pail assembly according to another aspect
of the
invention includes steps of mounting an upper portion of a flexible bag to an
upper portion of
a diaper bag assembly; and pushing a lower portion of the flexible bag
downwardly through a
resilient rotatable sealing and gripping member having a bag engaging surface
that has a
kinetic frictional coefficient with respect to an outer surface of the
flexible bag that is
substantially within a range of about 0.37 to about 0.67.
[00031] A method of using a diaper pail assembly according to another aspect
of the
invention includes steps of installing a flexible bag into a diaper pail
assembly, the flexible
bag having an inner surface that has a kinetic frictional coefficient with
respect to like
material that is substantially within a range of about 0.08 to about 0.38;
inserting a waste
package into the flexible bag; and removing the flexible bag from the diaper
pail assembly.
[00032] A method of using a diaper pail assembly according to a another aspect
of the
invention includes providing a bag assembly having a bag frame and an attached
flexible bag,
the bag frame having a central opening, the central opening having a minimum
lateral
dimension that is substantially within a range of about 60 mm to about 180 mm;
installing the
bag assembly into a diaper pail assembly; inserting a waste package into the
flexible bag; and
removing the bag assembly from the diaper pail assembly.
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[00033] A method of using a diaper pail assembly according to another aspect
of the
invention includes providing a bag assembly having a bag frame that is
foldable about a hinge
and that has a central opening, the bag assembly further including a flexible
bag that is
attached to the bag frame; installing the bag assembly into a diaper pail
assembly; inserting a
waste package into the flexible bag; and removing the bag assembly from the
diaper pail
assembly, the step of removing the bag assembly from the diaper pail assembly
including a
step of folding the bag frame about the hinge in order to form a carrying
handle for the bag
assembly.
[00034] A method of using a diaper pail assembly according to another aspect
of the
invention includes installing a flexible bag into a diaper pail assembly, the
flexible bag having
an outer surface and an inner surface; engaging the outer surface of the
flexible bag to create a
twist in the flexible bag; dispensing a powder material into an upper portion
of the flexible
bag above the twist; and inserting a waste package into the flexible bag by
pushing the waste
package downwardly through the twist, whereby a portion of the powder material
is pushed
with the waste package through the twist into a lower portion of the flexible
bag.
[00035] A method of using a diaper pail assembly according to another aspect
of the
invention includes installing a flexible bag into a diaper pail assembly, the
flexible bag having
an outer surface, an inner surface and a lubricating material disposed on at
least a portion of
the inner surface; engaging the outer surface of the flexible bag to create a
restricted portion
in the flexible bag; and inserting a waste package into the flexible bag by
pushing the waste
package downwardly through the restricted portion, whereby the lubricating
material
facilitates passage of the waste package through the restricted portion.
[00036] These and various other advantages and features of novelty that
characterize the
invention are pointed out with particularity in the claims annexed hereto and
forming a part
hereof. However, for a better understanding of the invention, its advantages,
and the objects
obtained by its use, reference should be made to the drawings which form a
further part
hereof, and to the accompanying descriptive matter, in which there is
illustrated and described
a preferred embodiment of the invention.
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BRIEF DESCRIPTION OF THE DRAWINGS
[00037] FIGURE 1 is a perspective view depicting a diaper pail assembly that
is
constructed according to a preferred embodiment of the invention, shown in an
open position;
[00038] FIGURE 2 is a second perspective view depicting the diaper pail
assembly that is
shown in FIGURE 1, shown in a closed position;
[00039] FIGURE 3 is a side elevational view depicting the diaper pail assembly
that is
shown in FIGURE 1;
[00040] FIGURE 4 is a fragmentary cross-sectional view depicting a portion of
the diaper
pail assembly that is shown in FIGURE 1;
[00041] FIGURE 5 is another fragmentary cross-sectional view depicting a
portion of the
diaper pail assembly that is shown in FIGURE 1;
[00042] FIGURE 6 is a side elevational view depicting the diaper pail assembly
that is
shown in FIGURE 1, shown in a closed position;
[00043] FIGURE 7 is a top plan view depicting the diaper pail assembly that is
shown in
FIGURE 6;
[00044] FIGURE 8 is a bottom plan view showing the diaper pail assembly that
is shown in
FIGURE 6;
[00045] FIGURE 9 is a second side elevational view showing the diaper pail
assembly that
is shown in FIGURE 6;
[00046] FIGURE 10 is a front elevational view depicting the diaper pail
assembly that is
shown in FIGURE 6;
[00047] FIGURE 11 is a rear elevational view depicting the diaper pail
assembly that is
shown in FIGURE 6;
[00048] FIGURE 12 is a fragmentary perspective view depicting a transmission
mechanism
within the diaper pail assembly that is shown in FIGURE 1;
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[00049] FIGURE 13 is a fragmentary perspective view depicting another portion
of the
transmission mechanism shown in FIGURE 12;
[00050] FIGURE 14 is a fragmentary cross-sectional view depicting another
portion of the
transmission mechanism shown in FIGURE 12;
[00051] FIGURE 15 is a fragmentary cross-sectional view depicting another
portion of the
diaper pail assembly that is shown in FIGURE 1;
[00052] FIGURE 16 is a fragmentary perspective view depicting a portion of the
diaper pail
assembly that is shown in FIGURE 1;
[00053] FIGURE 17 is a top plan view of one component of the diaper pail
assembly that is
shown in FIGURE 1;
[00054] FIGURE 18 is a cross-sectional view taken along lines 18-18 in FIGURE
17;
[00055] FIGURE 19 is a cross-sectional view taken along lines 19-19 in FIGURE
17;
[00056] FIGURE 20 is a diagrammatical depiction of the diaper pail assembly
shown in
FIGURE 1 in use;
[00057] FIGURE 21 is a top plan view of a diaper pail bag assembly that is
constructed
according to the preferred embodiment of the invention;
[00058] FIGURE 22 is a bottom plan view of the diaper pail bag assembly that
is shown in
FIGURE 21;
[00059] FIGURE 23 is a cross-sectional view taken along lines 23-23 in FIGURE
22;
[00060] FIGURE 24 is a cross-sectional view taken along lines 24-24 in FIGURE
22;
[00061] FIGURE 25 is a fragmentary depiction of the diaper pail bag assembly
shown in
FIGURE 21 in a closed position;
[00062] FIGURE 26 is a diagrammatical cross-sectional view taken along lines
26-26 in
FIGURE 25;
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[00063] FIGURE 27 is an isolation view of one component of the diaper pail bag
assembly
shown in FIGURE 21;
[00064] FIGURE 28 is an exploded cross-sectional view taken along lines 28-28
in
FIGURE 25;
[00065] FIGURE 29 is an exploded cross-sectional view taken along lines 29-29
in
FIGURE 25; and
[00066] FIGURE 30 is an exploded cross-sectional view taken along lines 30-30
in
FIGURE 25; and
[00067] FIGURE 31 is a diagrammatical depiction of the film material that is
used in the
diaper pail bag assembly shown in FIGURE 21.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[00068] Referring now to the drawings, wherein like reference numerals
designate
corresponding structure throughout the views, and referring in particular to
FIGURE 1, a
diaper pail assembly or system 10 that is constructed according to a preferred
embodiment of
the invention includes a housing 12 and a lid member 14. Lid member 14 is
connected to the
housing 12 by a hinge mechanism 16 so that the lid member 14 can be moved by a
parent or
caregiver between an open position that is shown in FIGURE 1 and a closed
position that is
shown in FIGURE 2.
[00069] Housing 12 defines an interior storage space 13, best shown in FIGURE
5, which
can be accessed by a parent or a caregiver by opening a door 18. The door 18
is hingedly
mounted with respect to the housing 12. Diaper pail assembly 10 further
includes a base
portion 20 that is constructed and arranged to support the housing 12 on an
underlying
horizontal surface such as a floor or a carpet.
[00070] A latching mechanism and gripping knob 22 is provided on the door 18
for
permitting the consumer to open and close the door 18 in conventional fashion.
The latching
mechanism and gripping knob 22 further includes a latch mechanism of
conventional design
that interengages with a portion of the housing 12 in order to selectively
lock the door 18 in a
closed position as shown in FIGURE 1. The door 18 is also preferably provided
with a
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menhanism for releasably retaining the door 18 in the open position, so that
the door 18 will
not swing shut at a time that is inconvenient for the consumer'.
[00071] A lid latching mechanism 24 includes a laterally expandable latch
member 26 that
is movably mounted on the lid member 14 and a mating recess 28 that is defined
in the
housing 12. Referring briefly to noun 4, a button or actuating surface 30 is
movably
mounted on a side of the lid member 14 that is opposite the binge mechanism 16
and is
constrained with respect to the lid member 14 so as to permit only
substantially vertically
upward and downward movement with respect to the lid member 14. A slotted
plunger
member 32 is integral with an 'underside of the actuating surface 30 and is
constructed and
arranged to cam against outer cam surfaces 25 of an opposed pair of pivotally
mounted
laterally expandable lath members 34,36 when the actuating surface 30 is
depressed by a
consumer, Latch members 34,36 are biased by an internal spring towards the
open position
that is shown in FIGURE 4,
[00072] When a consumer closes the lid member 14, curved lower services 27 of
the latch
members 34,36 cam the latch members 34, 36 inwardly, permitting the recessed
surfaces 29
, of the respective latch members 34,36 to engage with the surface on the
housing 12 that
defines the recess 28. This movement creates a temporary deceleration and then
a sharp
acceleration at the end of the lid closing process that has a tendency to
cause a small amount
of odor absorbing or odor masking powder to be dispensed from a powder
dispensing
assembly 40 that is mounted to a mining receptacle 42 that is secured to the
underside of the
lid member 14, best shown in FIGURE 1.
[0607] The powder dispensing Assembly 40 and its method of operation is
preferably
constructed as described in co-pending U.S. Patent Application S.N.12/609,136,
filed October
30, 2009. =
(00074] Powder dispensing assembly 40 is preferably constructed and arranged
to dispense
a deodorizing or odor-absorbing powder such as sodium bicarbonate into a
targeted area of
the diaper pail assembly 10. It preferably includes a directional dispensing
mechanism
including an orifice for dispensing powder from the assembly 40 in such a
manner that initial
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dispersal of the powder is concentrated to a single side of the powder
dispensing assembly 40
that is preferably away from the hinge mechanism 16.
[00075] When a consumer desires to open the lid member 14 of the diaper pail
assembly 10
in order to install a diaper pail bag or dispose an odiferous waste package
such as a used
disposable diaper, he or she will depress the actuator button 30, which will
drive the plunger
32 downwardly, causing the plunger 32 to contact the outer cam surfaces 25 of
the respective
latch members 34, 36. This will cause the latch members 34, 36 to disengage
from the recess
28 and enable the lid member 14 to be lifted upwardly.
[00076] An undercut 31 or recess is preferably defined in the housing 12 on an
opposite
side of housing 12 from the hinge mechanism 16 in order to give the consumer
space to be
able to exert lifting pressure on a lifting surface 33 of the lid member 14,
as may be visualized
by viewing FIGURE 1. This will enable a parent or caregiver to easily lift the
lid member 14
after the lid latching mechanism 24 has been disengaged.
[00077] Referring now to FIGURE 5, diaper pail assembly 10 advantageously
includes
structure 44 for aligning and centering a diaper pail bag within the interior
storage space 13 of
the housing 12. In the preferred embodiment, the aligning and centering
structure 44 includes
a bottom surface 46 defining a lowermost extent of the interior storage space
13 that includes
a central, substantially flat portion 48 and an annular curved portion 50
surrounding the
substantially flat portion 48.
[00078] Alternatively, the bottom surface 46 could be entirely concavely
curved, or the
central portion could even have a slight convex curvature. The portion 50
could alternatively
achieve its centering and aligning function if it was generally flat, or even
slightly convex, as
long as it is raised with respect to the central portion 46 and generally
annular.
[00079] The central substantially flat portion 48 is preferably substantially
circular in shape
as viewed in top plan and has a maximum radius R1 that is preferably
substantially within a
range of about 20 mm to about 130 mm, more preferably within a range of about
30 mm to
about 100 nun and most preferably within a range of about 45 mm to about 85
mm.
Alternatively, the central portion 48 could have a generally oval shape as
viewed in top plan.
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[00080] The annular curved portion 50 occupies a substantial portion of the
bottom surface
46 and is substantially concave, having an average radius of curvature R2 that
is preferably
within a range of about 15 mm to about 120 mm. More preferably, the average
radius of
curvature R2 of the annular curved portion 50 is substantially within a range
of about 25 mm
to about 80 mm, and most preferably within a range of about 30 mm to about 60
mm.
[00081] In terms of surface area, the curved concave portion 50 is preferably
substantially
at least 25% of the bottom surface 46 as a whole, more preferably
substantially at least 40%
of the surface area of the bottom surface 46 and most preferably substantially
at least 60% of
the surface area of the bottom surface 46.
[00082] The bottom surface 46 may additionally include a small upper ledge
portion 52 at
its extreme outer periphery, connected to the annular concave portion 50 by a
concave portion
that is shaped to provide a smooth transition between the annular concave
portion 50 and the
upper ledge portion 52. The entire bottom surface 46 is constructed so as to
have a maximum
lateral extent, which in the preferred embodiment is represented by a maximum
radius R3,
that is preferably substantially within a range of about 60 mm to about 250
mm, more
preferably substantially within a range of about 80 mm to about 180 mm, and
most preferably
substantially within a range of about 90 mm to about 150 mm.
[00083] A ratio R2/R3 is preferably substantially within a range of about 0.15
to about 0.95,
more preferably substantially within a range of about 0.20 to about 0.60, and
most preferably
within a range of about 0.25 to about 0.45.
[00084] The bottom surface 46 also preferably is fabricated from a material,
preferably
polypropylene, that has a kinetic coefficient of friction with respect to like
material that is
substantially within a range of about 0.41 to about 0.71, more preferably
substantially within
a range of about 0.46 to about 0.66, and most preferably substantially within
a range of about
0.51 to about 0.61.
[00085] The bottom surface 46 also preferably is fabricated from a material
that has a static
coefficient of friction with respect to like material that is substantially
within a range of about
0.54 to about 0.84, more preferably substantially within a range of about 0.59
to about 0.79,
and most preferably substantially within a range of about 0.64 to about 0.74.
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[00086] The bottom surface 46 and the external surface of the flexible bag 112
are also
preferably fabricated from materials that create a relative static coefficient
of friction
therebetween that is substantially within a range of about 0.30 to about 0.60,
more preferably
substantially within a range of about 0.35 to about 0.55, and most preferably
substantially
within a range of about 0.40 to about 0.50.
[00087] The bottom surface 46 and the external surface of the flexible bag 112
are also
preferably fabricated from materials that create a relative kinetic
coefficient of friction
therebetween that is substantially within a range of about 0.17 to about 0.47,
more preferably
substantially within a range of about 0.22 to about 0.42, and most preferably
substantially
within a range of about 0.27 to about 0.37.
[00088] The presence of the annular concave portion 50 has a beneficial effect
of aligning
and centering the diaper pail bag in order to enhance the effectiveness of the
twist seal 120
that will be described in greater detail below and to optimize the space
efficiency within the
flexible bag 112 and within the internal storage space 13.
[00089] As can be visualized by viewing FIGURE 20, the sloped walls of the
annular
portion 50 will direct the center of mass of a lower portion 116 of the
flexible bag 112
radially inwardly toward a longitudinal axis of the housing 12 of the diaper
pail assembly 10.
As waste packages 118 are inserted into the lower portion 116 of the flexible
bag 112, the
resulting expansion will tend to occur radially outwardly and evenly in all
directions, thus
taking advantage of the entire storage space 13 within the housing 12 in a
space-efficient
manner. As a result, more diapers may be stored within the diaper pail
assembly 10 before it
needs to be emptied than would otherwise be the case.
[00090] Diaper pail assembly 10 further preferably includes a rotatable
sealing and gripping
member 54 that is constructed and arranged to create a restricted portion
within the flexible
diaper pail bag 112 in order to provide a temporary odor seal. In the
preferred embodiment,
this is accomplished by gripping and twisting the flexible diaper pail bag 112
in order to
provide a temporary seal, as will be described in greater detail below.
Alternatively, the
restricted portion could be created by pinching or folding a portion of the
flexible bag 112
instead of by twisting it.
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[00091] A transmission mechanism 56 is provided for causing rotation of the
rotatable
sealing member 54 for a predetermined rotational distance when the lid member
14 is moved
from the open position shown in FIGURE 1 to the closed position shown in
FIGURE 2.
Transmission mechanism 56 includes a push rod member 58, visible in FIGURES 1
and 12-
14, that is caused and constrained to slide linearly downwardly when the lid
member 14 is
closed and linearly upwardly when it is opened. Transmission mechanism 56 is
designed so
as not to cause any movement of the rotatable sealing member 54 when the lid
member 14 is
pivoted upwardly from the closed position to the open position.
[00092] Preferably, transmission mechanism 56 is constructed and arranged to
cause the
rotatable sealing member 54 to rotate a predetermined angular distance when
the lid member
14 is closed. Preferably, this predetermined angular distance is substantially
within a range of
about 108 degrees to about 540 degrees, more preferably substantially within a
range of about
of about 120 degrees to about 450 degrees and most preferably substantially
within a range of
about 162 degrees to about 288 degrees.
[00093] Transmission mechanism 56 is depicted in greater detail in FIGURES 12-
14. In
the preferred embodiment, the push rod member 58 includes a toothed rack
portion 60 that is
best visible in FIGURE 13. The push rod member 58 is constrained to permit
only vertical
movement thereof with respect to the housing 12 by a slotted channel within
the internal
housing frame 70. A rack engaging gear 59 is mounted for rotation with respect
to the
internal housing frame 70 in such a manner that it is permitted a limited
amount of vertical
movement with respect to the internal housing frame 70. Rack engaging gear 59
has teeth
that are operatively engaged with corresponding teeth on the toothed rack
portion 60 when the
rack engaging gear 59 is in its lowermost vertical position.
[00094] Transmission mechanism 56 further includes a second compound gear 62
having a
first gear portion 68 and a second gear portion 69 that have common axes of
rotation and are
joined for common movement except when a predetermined transmission force
therebetween
is exceeded, when a clutch mechanism 63 will incrementally permit relative
angular
displacement therebetween in order to relieve internal forces within the
transmission
mechanism 56 and avoid damage to the diaper pail assembly 10.
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[00095] The first gear portion 68 is operatively engaged with the rack
engaging gear 59, and
the second gear portion 69 is operatively engaged with a third compound gear
65 having a
first gear portion 66 and a second gear portion 67. The third compound gear 65
is formed so
that the first and second gear portions 66, 67 are integrally formed and are
mounted for
common rotation about a common axis. The first gear portion 66 of the third
compound gear
65 is in operative engagement with the second gear portion 69 of the second
compound gear
62. The second gear portion 67 of the third compound gear 65 is in operative
engagement
with a toothed rack portion 82 that is formed on an underside of a rotatable
flexible bag
retaining and sealing member 54 that will be discussed in greater detail
below.
[00096] When the lid member 14 is pivoted downwardly by a parent or caregiver
from the
open position that is shown in FIGURE 1 to the closed position that is shown
in FIGURE 2,
the push rod member 58 will be driven downwardly and the rotatable flexible
bag retaining
and sealing member 54 will be driven by the gear train mechanism 61 to rotate
for the
predetermined angular distance, thereby creating a twisted portion 120 in an
intermediate
portion 113 of the flexible bag 112 that is between a lower or bottom portion
116 and an
upper portion 114. This is diagrammatically shown in FIGURE 20.
[00097] The gear train mechanism 61 is operatively interconnected when the
push rod
member 58 moves downwardly, because the rack engaging gear 59 is in its
lowermost vertical
position and operatively engaged with the second compound gear 62. However,
when the lid
member 14 is pivoted upwardly from the closed position to the open position,
the rack
engaging gear 59 is lifted upwardly out of engagement with the second compound
gear 62.
Accordingly the gear train mechanism 61 will be disengaged and there will be
no rotation of
the flexible bag retaining and sealing member 54 when the lid member 14 is
opened, which
allows the twisted bag to remain closed.
[00098] As may be visualized by viewing FIGURE 20, the motion of pushing the
waste
package 118 downwardly through the twisted portion 120 may have the temporary
effect of
reducing the degree of twist in the twisted portion 120. However, when the lid
member 14 is
closed, the amount of twist in the twisted portion 120 is increased, which
reinforces the
quality of the odor seal that is created by the twisted portion 120.
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[00099] In the event that the gear train mechanism 61 becomes jammed, internal
forces
within the gear train mechanism 61 will cause the clutch mechanism 63 to
permit a relative
amount of relative movement between the first gear portion 68 and the second
gear portion of
the second compound gear 62. Clutch mechanism 63 includes two relatively
slidable
components that are biased together by a spring member 64, best shown in
FIGURE 14,
which is operatively interposed between the second compound gear 62 and the
internal
housing frame 70.
[000100] Referring now to FIGURE 16, the flexible bag retaining and sealing
member 54
preferably includes a main body portion 71 having an outer flange 72 that
defines an upper
surface 74, which is preferably substantially flat. Alternatively, the upper
surface 74 could be
shaped so that it is slightly convex. A plurality of retaining members 76 are
defined as
projections that are integral with a portion 78 of the internal housing frame
70. These are
constructed and arranged to vertically constrain the flexible bag retaining
and sealing member
54 so that is permitted to rotate with respect to the internal housing frame
70 but is precluded
from upward vertical movement.
[000101] The retaining members 76 and the upper surface 74 of the outer flange
72 are
preferably constructed and arranged to minimize relative friction
therebetween. The relative
kinetic coefficient of friction between the retaining members and the upper
surface 74 is
preferably substantially within a range of about 0.12 to about 0.32, and more
preferably
substantially within a range of about 0.17 to about 0.27.
[000102] The relative static coefficient of friction between the retaining
members and the
upper surface 74 is preferably substantially within a range of about 0.23 to
about 0.43, and
more preferably substantially within a range of about 0.28 to about 0.38.
[000103] In addition, a lower surface 80 of the outer flange 72 is supported
for low friction
rotation with respect to the internal housing frame 70 by a plurality of
bearing members 77, as
is best shown in FIGURE 15. In the preferred embodiment, the bearing members
77 are
positioned to bear against a lower surface of a lower outer flange projection
73 of the outer
flange 72. Bearing members 77 are preferably fabricated out of a material
having a relatively
low coefficient of friction, such as nylon, polytetrafluoroethylene (PTFE) or
polyoxymethylene (POM). Most preferably, bearing members 77 are fabricated
from POM.
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[000104] FIGURE 15 also shows that the housing 12 preferably has a finger
access recess 75
defined therein for permitting a parent or caregiver to place a finger against
the lower surface
88 of the bag frame 90 in order to prise the bag frame 90 upwardly in order to
disengage it
from the housing 12. The consumer will perform such an action when removing
the flexible
bag assembly 110 from the diaper pail assembly 10. The inherent flexibility of
the bag frame
90 permits the bag frame 90 to be elastically deformed to the extent that is
necessary to
remove it from the housing 12 in this manner.
[000105] Referring again to FIGURE 16, the main body portion 71 of the
flexible bag
retaining and sealing member 54 preferably includes an upper flange portion 84
having a
narrow, convexly curved upper surface 86 that defines a low friction surface
for supporting a
lower surface 88 of a bag frame 90 that is part of a flexible bag assembly
110.
[000106] The upper surface 86 of the upper flange portion 84 preferably has a
kinetic
frictional coefficient with respect to like material that is substantially
within a range of about
0.30 to about 0.50, and that is more preferably substantially within a range
of about 0.35 to
about 0.45. This ensures that the flexible bag retaining and sealing member 54
can
simultaneously perform the function of supporting the underside of the bag
frame 90 while
being able to freely rotate with minimal friction. The flexible bag assembly
110 will be
described in greater detail below.
[000107] The main body portion 71 of the flexible bag retaining and sealing
member 54 is
preferably fabricated from a rigid plastic material, such as nylon, acetyl or
POM, most
preferably the latter, and preferably has a relatively low frictional
coefficient with respect to
like material. The flexible bag retaining and sealing member 54 further
includes a radially
inner resilient portion 92 including a plurality of inwardly extending
resilient finger members
94 that are configured to operatively interact with the flexible bag 112 in a
complex manner
that includes engaging the intermediate portion 113 of the flexible bag 112 to
create a twisted
portion 120 in order to effectively seal odors within the lower portion 116 of
the flexible bag
assembly 110 during use. This may be visualized by viewing FIGURE 20.
[000108] The inner resilient portion 92 of the flexible bag retaining and
sealing member 54
is also constructed in such a manner to make it easy for a parent or caregiver
to push the
lower portion 116 of the bag assembly 110 through the central portion of the
inner resilient
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portion 92 during initial installation of a flexible bag assembly 110 into the
diaper pail
assembly 10. This is achieved through a combination of the unique shape of the
individual
resilient finger members 94, the shape of the spaces or slots 95 that are
defined between the
individual finger members 94 and the degree of elasticity and frictional
characteristics of both
the finger members 94 and the outer and inner surfaces of the flexible bag
112.
[000109] FIGURE 17 is a top plan view of a flexible bag retaining and sealing
member 54
that is constructed according to a preferred embodiment of the invention. In
this
embodiment, six resilient finger members 94 are spaced about an inner
periphery of the main
body portion 71 and extend radially inwardly to a central opening 96. Six
spaces or slots 95
are respectively defined between the adjacent finger members 94, with each of
the finger
members 94 and spaces 95 having substantially the same shape and dimensions in
the
preferred embodiment. Alternatively, the shape of the finger members 94 and
the slots 95
could be varied.
[000110] Each of the finger members 94 includes a distal, radially innermost
end portion
terminating at a convexly radiused tip 101 that is preferably shaped to have a
radius of
curvature that is substantially within a range of about 0.5 mm to about 3.0
mm. More
preferably, the convexly radius tips 101 are shaped to have radius of
curvature that is
substantially within a range of about 0.9 mm to about 1.9 mm. Tip portion 101
is also
preferably thickened with respect to adjacent portions of the flexible fingers
94, as is
discussed below.
[000111] The convexly radiused tips 101 of the respective finger members 94
together define
the central opening 96, which preferably has a minimum diameter DI that is
substantially
within a range of about 3 mm to about 13 mm, and more preferably within a
range of about 5
mm to about 11 mm. Most preferably, the minimum diameter DI is substantially
within a
range of about 6 mm to about 10 mm.
[000112] Each of the finger members 94 is also preferably shaped so as to have
a pair of side
edges 98, 100, each of which is curved and preferably slightly concave so that
each of the
spaces defined by a pair of the opposing side edges 98, 100 is wider in a
radially intermediate
location than it is at the radially innermost location and a radially
outermost locations. The
average radius of curvature of each of the side edges 98 is preferably
substantially within a
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range of about 50 mm to about 400 mm, and more preferably substantially within
a range of
about 100 mm to about 250 mm. The curvature of the opposing side edges 98, 100
can be
substantially constant, or it can alternatively be variable or formed of two
or more compound
curves.
[000113] As FIGURE 17 shows, the finger members 94 are preferably shaped and
sized so
that at least one of the spaces 95, when in an unstressed position, has a
first width WI at a first
location 102, which is preferably at an intermediate radial location along the
finger members
94 where the width of the space 95 is at a maximum. Preferably, the first
location 102 is
located substantially at a radial midpoint of the opposing adjacent finger
members 94. Each
space 95 further has a second width W2 at a second location 104, which is
preferably near the
distal end of the respective finger members 94 where the width is at a
minimum. The first
width WI is preferably greater than the second width W2.
[000114] The space 95 further has a third width W3 defined at a third location
106 that is
preferably near the radially outermost, proximal end of the respective finger
members 94
where the width is at a minimum. The first width WI is preferably greater than
the third width
W3.
[000115] The first, second and third locations 102, 104, 106 are accordingly
radially spaced
from each other, with the first location 102 being radially intermediate
between the second
and third locations 104, 106.
[000116] The first width WI is preferably substantially within a range of
about 3 mm to
about 11 mm, more preferably substantially within a range of about 4.5 mm to
about 9.5 mm,
and most preferably substantially within a range of about 6 mm to about 8 mm.
[000117] The second width W2 is preferably substantially within a range of
about 0.5 mm to
about 5 mm, and more preferably within a range of about 1.5 mm to about 3.5
mm.
[000118] A ratio of the first width W1 to the second width W2 is preferably
substantially
within a range of about 1.5 to about 4.0, and more preferably substantially
within a range of
about 2.0 to about 3.5.
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[000119] The third width W3 is preferably substantially within a range of
about 0.5 mm to
about 5 mm, and more preferably within a range of about 1.5 mm to about 3.5
mm.
[000120] A ratio of the first width WI to the third width W3 is preferably
substantially within
a range of about 1.5 to about 4.0, and more preferably substantially within a
range of about
2.0 to about 3.5.
[000121] FIGURES 18 and 19 are cross-sectional views taken along lines 18-18
and 19-19,
respectively, in FIGURE 17. These figures show that each of the resilient
finger members 94
includes an upper surface 97 that is curved concavely with a varying radius of
curvature so
that the radially outermost portion between the first and third locations 102,
106 as viewed in
FIGURE 17 has a smaller radius of curvature and is therefore more curved than
the radially
innermost portion between the first and second locations 112, 104.
Accordingly, each of the
resilient finger members 94 initially curves downwardly from its proximal
connection to the
main body portion 71 and then flattens out, extending substantially
horizontally from its
intermediate portion to its most distal portion. The lower surfaces 99
accordingly have a
convex curvature that is more pronounced in the proximal portion of the finger
94 than in the
distal portion.
[000122] The lower surfaces 99 of each of the respective resilient finger
members 94 are also
preferably spaced from the upper surface 97 so that each of the finger members
94 has a
substantially constant thickness, which is preferably substantially within a
range of about 0.5
mm to about 3.0 mm, and more preferably substantially within a range of about
1.0 mm to
about 2.0 mm.
[000123] The distal, radially innermost tip portions 101 of the finger members
94 are
preferably slightly thickened with respect to the adjacent blade portions, as
is best shown in
FIGURE 19. The thickened tip portions 101 preferably have a thickness that is
preferably
substantially within a range of about 1.0 mm to about 6.0 mm, and more
preferably
substantially within a range of about 1.5 mm to about 4.5 mm.
[000124] The resilient finger members 94 are preferably fabricated from a
flexible
elastomeric material, which is most preferably a plastic material such as a
thermoplastic
urethane (TPU) material having a Shore A hardness that is preferably
substantially within a
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range of about 60 to about 120, is more preferably substantially within a
range of about 70 to
about 110 and most preferably substantially within a range of about 80 to
about 100.
Alternatively, a thermoplastic elastomer (TPE) material or a thermoplastic
resin (TPR) could
be used.
[000125] The material from which the resilient finger members 94 are
fabricated preferably
has a static coefficient of friction with respect to like material that is
substantially within a
range of about 0.70 to about 0.95, that is more preferably substantially
within a range of about
0.80 to about 0.94 and that is most preferably substantially within a range of
about 0.85 to
about 0.89. This material further preferably has a kinetic coefficient of
friction with respect
to like material that is substantially within a range of about 0.37 to about
0.67, more
preferably substantially within a range of about 0.42 to about 0.62 and that
is most preferably
substantially within a range of about 0.47 to about 0.57. .
[000126] In addition, at least the portions of each of the resilient finger
members 94 that will
contact the flexible bag 112 preferably has a static coefficient of friction
with respect to the
external surface of the flexible bag 112 that is substantially within a range
of about 0.59 to
about 0.89, that is more preferably substantially within a range of about 0.64
to about 0.84
and that is most preferably substantially within a range of about 0.69 to
about 0.79. . This
material further preferably has a kinetic coefficient of friction with respect
to the external
surface of the flexible bag 112 that is substantially within a range of about
0.34 to about 0.64,
more preferably substantially within a range of about 0.39 to about 0.59 and
that is most
preferably substantially within a range of about 0.44 to about 0.54.
[000127] The external surface of the flexible bag 112 is preferably fabricated
from a material
that has a static coefficient of friction with respect to like material that
is substantially within
a range of about 0.18 to about 0.48, that is more preferably substantially
within a range of
about 0.23 to about 0.43 and that is most preferably substantially within a
range of about 0.28
to about 0.38. This material further preferably has a kinetic coefficient of
friction with
respect to like material that is substantially within a range of about 0.12 to
about 0.47, more
preferably substantially within a range of about 0.15 to about 0.42 and that
is most preferably
substantially within a range of about 0.18 to about 0.38.
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[000128] The internal surface of the flexible bag 112 is preferably fabricated
from a material
that has a static coefficient of friction with respect to like material that
is substantially within
a range of about 0.17 to about 0.47, that is more preferably substantially
within a range of
about 0.22 to about 0.42 and that is most preferably substantially within a
range of about 0.27
to about 0.37. This material further preferably has a kinetic coefficient of
friction with
respect to like material that is substantially within a range of about 0.08 to
about 0.38, more
preferably substantially within a range of about 0.13 to about 0.33 and that
is most preferably
substantially within a range of about 0.18 to about 0.28.
[000129] FIGURE 20 is a diagrammatical depiction of a diaper pail assembly 10
that is
constructed according to the preferred embodiment of the invention, shown in
operation. A
bag assembly 110 having a bag frame portion 90 that is attached to an upper
portion 114 of a
flexible bag 112 is installed by a parent or caregiver into the diaper pail
assembly 10 by
seating the bag frame 90 into the housing 12 of the diaper pail assembly 10 in
a manner that
will be described in greater detail below.
[000130] The parent or caregiver will then push the lower portion 116 of the
flexible bag 112
downwardly into the internal storage space 13 of the housing 12 by pushing it
through the
resilient flexible fingers 94 of the flexible bag retaining and sealing member
54. The lid
member 14 is then closed, which causes the flexible bag retaining and sealing
member 54 to
rotate by a predetermined angular distance to create a twisted portion 120 in
the intermediate
portion 113 of the flexible bag 112.
[000131] The parent or caregiver will use the diaper pail assembly 10 by
inserting a waste
load package 118 such as a used disposable diaper into the lower portion 116
of the flexible
bag 112 by pushing it downwardly through the twisted portion 120 of the
intermediate portion
113 of the flexible bag 112. This is performed against the resistance bias
that is applied by
the resilience of the resilient finger members 94. As the parent or caregiver
pushes the waste
load package 118 downwardly through the twisted portion 120, the tapered, leaf-
like pattern
of each resilient finger member 94 and space 95 helps the bag 112 slide along
the opposed
edges 98, 100 that define the.space 95. In addition, when the lid member 14 is
closed, the
tapered, leaf-like pattern of each resilient finger member 94 and space 95
helps to reduce drag
between the bag 112 and the flexible bag retaining and sealing member 54.
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[000132] The bottom portion 116 of the flexible bag 122 is not expected to
move
substantially with respect to the housing 12 during the creation of the
twisted portion 120,
particularly when it is weighted down by a number of waste packages 118.
Accordingly, the
degree of twist that is created in the flexible bag 112 by the rotation of the
retaining and
sealing member 54 when the lid member 14 is closed is expected to be
comparable and at
least equal to the predetermined amount of angular rotation of the retaining
and sealing
member 54. In practice, the degree of twist in the flexible bag 112 will be
more than the
predetermined amount of angular rotation of the retaining and sealing member
54 after
insertion of the second waste package 118, because a certain amount of
residual twisting will
remain in the twisted portion 120 even after the first waste package 118 is
pushed through the
twisted portion 120.
[000133] As is described in greater detail below with reference to FIGURE 31,
both the
external and internal surfaces of the flexible bag 112 is also preferably
treated with a friction
reducing slip agent in order to further reduce drag between the bag 112 and
the flexible bag
retaining and sealing member 54. The internal surface is further treated or
impregnated with a
blocking agent in order to further reduce internal friction both with respect
to itself and with
respect to the waste packages 118.
[000134] As the consumer pushes the waste load package 118 downwardly through
the
twisted portion 120, the inherent resilience of the flexible bag 112 at the
twisted portion 120
in conjunction with the inward resilient bias that is imparted to the outer
surface of the
flexible bag 112 by the resilient finger members 94 keep the outermost
portions of the waste
package 118 tightly against the inner surface of the flexible bag 112, which
maintains an
effective odor seal even during insertion of the waste package 118 into the
lower portion 116
of the flexible bag 112. This minimizes leakage of odor from the lower portion
116 of the
flexible bag 12 through the twisted portion 120 where it could be detected by
the parent or
caregiver.
[000135] When the lid member 14 is closed, powder material such as sodium
bicarbonate is
dispensed from the powder disperser 40 into the upper portion 114 of the
flexible bag 112,
above the twisted intermediate portion 113. The powder material is retained in
the upper
portion 114 above the twisted intermediate portion 113 of the flexible bag 112
for a period of
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time before a portion of it is swept by the parent or caregiver into the lower
portion 116 of the
flexible bag as the parent of caregiver pushes a waste package 118 downwardly
through the
twisted intermediate portion 113. The powder material accordingly deodorizes
or absorbs
odor in the upper area of the diaper pail assembly 10 for a period of time
when it is positioned
within the upper portion 114 of the flexible bag 112, and later in the lower
portion 116 of the
flexible bag 112.
[000136] The process of pushing a waste package 118 such as a wrapped, used
disposable
diaper through the intermediate, twisted portion 113 of the flexible bag 112
is facilitated by
the low static and kinetic frictional characteristics of the innermost layer
204 of the film
material 190, shown in FIGURE 31. Moreover, the presence of the powder
material provides
additional lubrication to the inner surface of the flexible bag 122 in the
area of the twisted
intermediate portion 113.
[000137] To that end, the powder material, which is preferably sodium
bicarbonate, has a
preferred granularity that is expressed as a mean particle size maximum
dimension that is
substantially within a range of about 40 microns to about 140 microns. More
preferably the
mean particle size maximum dimension is substantially within a range of about
60 microns to
about 120 microns and most preferably substantially within a range of about 80
microns to
about 100 microns.
[000138] The powder material also preferably has a bulk density that is
substantially within a
range of about 48 lb/ft3 to about 78 lb/ft3, more preferably within a range of
about 53 lb/ft3 to
about 73 lb/ft3 and most preferably within a range of about 58 lb/ft3 to about
68 lb/ft3.
[000139] FIGURE 21 is a top elevational view of a flexible bag assembly 110
that is
constructed according to a preferred embodiment of the invention. Flexible bag
assembly 110
includes a flexible bag 112 that is preferably pleated so as to permit the
lower portion 116 of
the flexible bag 112 to expand to a cross-sectional area that is greater than
the cross-sectional
area of the flexible bag 112 at its point of attachment to the bag frame 90.
[000140] Bag frame 90 is preferably fabricated from a plastic material such as
high density
polyethylene, and includes a first portion 120 that is generally semicircular
in shape and a
second portion 122 that is also generally semicircular in shape.
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[000141] Bag frame 90 defines an upper surface 121, as is shown in FIGURE 21,
and a
lower surface 88 that is best shown in FIGURE 22. Bag frame 90 is preferably
constructed so
as to be foldable about a hinge portion 124 from the open position that is
shown in FIGURES
21 and 22 to the closed position that is shown in FIGURE 25. In the closed
position that is
shown in FIGURE 25, the closure of the bag frame 90 effectively closes the
upper portion
114 of the flexible bag 112 and prevents odors from escaping from the flexible
bag 112.
[000142] In addition, the bag frame 90 when in the closed position forms a
convenient
handle that is shaped and sized for a consumer to conveniently grip in order
to carry the
flexible bag 112, together with any waste load packages 118 that are stored
therein, to a
location that is remote from the diaper pail assembly 10 for final disposal of
the flexible bag
112 and the waste load packages 118.
[000143] Referring back to FIGURE 21, the hinge portion 124 is preferably
integrally
molded into the bag frame 90 and is formed as a linear area that has a reduced
cross-sectional
thickness, so as to permit folding of the bag frame 90 into the closed
position. The bag frame
90 further includes an annular inner surface 126 that defines a central
opening 128 that forms
the open end of the bag frame assembly 110 when the bag frame 90 is in the
open position.
The central opening 128 is preferably substantially circular and preferably
has a maximum
inner lateral dimension or diameter Di that is substantially within a range of
about 60 mm to
about 180 mm. More preferably, the inner diameter Di is substantially within a
range of
about 85 nun to about 150 mm.
[000144] Bag frame 90 also preferably is constructed to have an outer
circumferential
surface 130 that is preferably substantially circular in shape and that
defines a minimum outer
diameter Do that is preferably within a range of about 90 nun to about 270 mm,
more
preferably within a range of about 120 mm to about 250 mm and most preferably
within a
range of about 140 mm to about 230 mm.
[000145] The inner diameter Di represents a first diameter of the flexible bag
112 at a
location proximate the frame 90. The flexible bag 112 at its lower portion 116
further
includes a second diameter DL that is preferably the maximum diameter of the
entire flexible
bag 112. The second diameter DL is depicted in FIGURE 20, and should properly
be
measured for purposes of this document with the lower portion 116 of the bag
112 expanded
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to the maximum extent permitted by the construction of the bag 122 in a shape
that is circular
in transverse cross-section. Preferably, the second diameter DL is larger than
the first diameter
Di.
[000146] The second diameter DL is preferably substantially within a range of
about 9 cm to
about 40 cm, more preferably substantially within a range of about 13 cm to
about 30 cm, and
most preferably substantially within a range of about 15 cm to about 25 cm.
[000147] A ratio of the first diameter Di to the second diameter DL is
preferably substantially
within a range of about 0.20 to about 0.90, more preferably substantially
within a range of
about 0.40 to about 0.75, and most preferably substantially within a range of
about 0.50 to
about 0.70.
[000148] The flexible bag assembly 110 further is constructed so as to have a
length that is
preferably substantially within a range of about 30 cm to about 110 cm, more
preferably
within a range of about 40 cm to about 100 cm, and most preferably within a
range of about
50 cm to about 80 cm.
[000149] A plurality of male, radially outwardly extending projections 132,
134, 136, 138
are preferably integrally formed in the bag frame 90 for permitting secure
registration of the
bag frame 90 with respect to the housing 12 of the diaper pail assembly 10
during use.
Referring back briefly to FIGURE 16, a plurality of recesses 133 are defined
in the housing
12 for receiving the respective projections 132, 134, 136, 138 in such a
manner that the bag
frame 90 is secured against rotation relative to the housing 12 and is
securely oriented and
aligned in a horizontal position when the projections 132, 134, 136, 138 are
received within
the respective recesses 133.
[000150] In addition, structure that is embodied as a retaining projection 135
is preferably
provided in each of the respective recesses 133 for releasably locking the
respective
projection 132, 134, 136, 138 within the respective recess 133. The retaining
projections 135
are preferably fabricated from a substantially rigid plastic material and are
integral with the
housing 12 of the diaper pail assembly 10. The inherent flexibility of the
material from which
the bag frame 90 is fabricated permits the parent or caregiver to manipulate
the bag frame 90
into the secured position wherein each of the projections 132, 134, 136, 138
are positioned
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beneath the respective retaining projections 135. Similarly, the inherent
flexibility of the bag
frame 90 is utilized when removing the bag frame 90 from the housing 12.
[000151] Releasable locking structure 140 is also preferably provided on the
bag frame 90 in
order to permit the parent or caregiver to releasably lock the bag frame 90
into the closed
position that is shown in FIGURE 25. In the preferred embodiment, the
releasable locking
structure 140 includes a curved female recess 142 that is defined in the first
portion 120 of the
bag frame 90 and a mating curved male projection 144 that is defined in the
second portion
122 of the bag frame 90. The curved mating portions 142, 144 advantageously
and preferably
extend along most of the outer periphery of the respective portions 120, 122
of the bag frame
90 in order to effectively retain odors within the flexible bag assembly 110
when it is in the
closed position shown in FIGURE 25.
[000152] The releasable locking structure 140 accordingly is constructed and
arranged to
define an effective odor seal as well as a locking mechanism to retain the bag
frame 90 in the
closed position. The curved mating portions 142, 144 preferably have a
substantially constant
radius and preferably subtend an angular distance that is preferably
substantially within a
range of about 90 to about 179 , more preferably within a range of about 120
to about 179
and most preferably within a range of about 1500 to about 1790. The larger the
angular
distance covered by the curved mating portions 142, 144, the more effective
odor seal will be
created by the releasable locking structure 140.
[000153] As is shown in FIGURE 22, which is a bottom plan view of the bag
frame 90
shown in the open position, the male, radially extending projections 132, 134,
136, 138 are
preferably staggered about the outer periphery of the bag frame 90 so that the
projection pairs
134, 138 and 132, 136 are adjacent to each other but do not fully overlap when
in the closed
position shown in FIGURE 25. In the preferred embodiment, the projections 132,
134, 136,
138 are spaced so that there is a slight but not full overlap between the
corresponding
projection pairs 134, 138 and 132, 136. This permits the parent or caregiver
to use his or her
thumb and forefinger in order to gain leverage against one of the projection
pairs 134, 138 or
132, 136 in order to disengage the releasable locking structure 140 and move
the bag frame
90 from the closed position into the open position.
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[000154] As FIGURE 22 shows, each of the projections 132, 134, 136, 138 is
preferably
constructed so as to have an outer surface that is convexly about a radial
center locus 147.
The radial center locus 147 of the projection 134 is preferably spaced a first
distance L1 from
a vertical transverse centerline of the bag frame 90 and a second distance L2
from a horizontal
transverse centerline as viewed in bottom plan as shown in FIGURE 22. The
radial center
locus 147 of the projection 132 is preferably spaced by the second distance L2
from the
vertical transverse centerline and by the first distance L1 from the
horizontal centerline. The
projection 138 is preferably spaced by the first distance L1 from the
horizontal centerline and
by the second distance L2 from the vertical centerline, and the projection 136
is preferably
spaced by the first distance L1 from the vertical centerline and by the second
distance L2 from
the horizontal centerline.
[000155] Preferably, the first distance L1 is less than the second distance
L2. More
preferably, the first distance L1 has a ratio with respect to the second
distance L2 that is
preferably substantially within a range of about 0.60 to about 0.95 and that
is more preferably
within a range of about 0.75 to about 0.90. In an alternative embodiment, the
first distance L1
could be greater than the second distance L2.
[000156] Referring now to FIGURE 23, it will be seen that the female curved
mating portion
142 of the releasable locking structure 140 preferably has a small projection
150 defining an
undercut for receiving and retaining the male curved mating portion 144 in the
locked
position. As FIGURE 24 shows, the male curved mating portion 144 also
preferably includes
a projection 148 for engaging the projection 150 in the female curved mating
portion 142.
The female and male mating portions 142, 144 are shown in the secured
positions in
FIGURES 28-30.
[000157] The upper portion 114 of the flexible bag 112 has a complex and
advantageous
construction in order to ensure secure attachment to the lower surface 88 of
the bag frame 90.
It is preferably die cut in order to correspond to the shape of the bag frame
90.
[000158] Refening to FIGURES 22 and 25, it will be seen that a film
reinforcement insert
154 is bonded to a portion of the lower surface 88 that includes areas of the
first and second
portions 120, 122 as well as the hinge portion 124. The film reinforcement
insert 154 is
preferably fabricated from a film material that is substantially identical in
construction to the
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film material from which the flexible bag 112 is fabricated. It increases the
strength of the
seal that is formed between the upper portion 114 of the flexible bag in the
lower surface 88
of the bag frame 90. It also provides the additional benefit of providing some
reinforcement
to the hinge portion 124.
[000159] The film reinforcement insert 154 is shown in isolation in FIGURE 27
and includes
a first portion 156 that is bonded to the first portion 120 of the bag frame
90, as shown in
FIGURE 22, and a second portion 160 that is bonded to the second portion 122
of the bag
frame 90. The film reinforcement insert 154 is preferably tacked or heat
sealed to the lower
surface 88 using a hot tool such as a hot tip soldering iron prior to the
assembly of the upper
portion 114 of the flexible bag 112 to the bag frame 90.
[000160] The upper portion 114 of the flexible bag 112 further preferably
includes a primary
seal portion 162 that is bonded, tacked or heat sealed to a semicircular
portion of each of the
first and second portions 120, 122 of the bag frame 91 on the lower surface
88. The primary
seal portion 162 is integral with the upper portion 114 and includes a first
end 164, an
opposite second end 166 and a curved central portion 168. The first and second
ends 164,
166 preferably respectively have broadened end portions that in the preferred
embodiment are
substantially circular. The first and second ends 164, 166 are bonded by heat
sealing to the
respective film reinforcement inserts 154, which enhances the strength of the
ultimate bond
between the first and second ends 164, 166 and the underside 88 of the bag
frame 90.
[000161] Referring briefly to FIGURE 26, which is a diagrammatical cross-
sectional view
taken along lines 26-26 in FIGURE 25, the upper portion 114 of the flexible
bag 112 is
advantageously pleated in order to permit significant expandability of the
lower portion 116
of the flexible bag 112 with respect to the upper portion 114. The pleating is
constructed and
arranged in such a manner in the preferred embodiment that each pleat 176
includes three
plies 182, 184, 186 of the film material 190 from which the flexible bag 112
is fabricated,
with a first fold 178 being defined between the first and second plies 182,
184 and a second
fold 180 being defined between the second and third plies 184, 186. Each of
the pleats 176 is
preferably substantially parallel to adjacent pleats and is preferably
oriented so as to extend
parallel to a longitudinal axis of the flexible bag assembly 110 that is
substantially
perpendicular to the transverse plane in which the bag frame 90 is positioned
during use.
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[000162] The flexible bag 112 preferably includes at least two pleats 176
around the outer
periphery, more preferably at least four pleats 176 and most preferably at
least six pleats 176.
In the illustrated embodiment, the flexible bag 112 has eight pleats 176.
[000163] FIGURE 28 is an exploded cross-sectional view taken along lines 28-28
in
FIGURE 25. The primary seal 162 is constructed and manged so that all three
plies of the
upper portion 114 are bonded to each other, with the inwardmost ply 182 being
directly
bonded to the lower surface 88 of the bag frame 90. This is also shown in
FIGURE 29, which
is an exploded cross-sectional view taken along lines 29-29 and FIGURE 25.
FIGURE 30 is
an exploded cross-sectional view taken along lines 30-30 in FIGURE 25, showing
a portion
of the primary seal 162 at a portion of the upper flexible bag portion 114
between adjacent
pleats 176. In this location, which is between adjacent pleats 176, only a
single layer of the
film material 190 overlies the lower surface 88 of the bag frame 90.
[000164] As is best shown in FIGURE 25, a bag assembly 110 according to the
preferred
embodiment also preferably and advantageously includes a plurality of
secondary seals 170
that are formed in the upper portion 114 of the flexible bag 112 in an area
that is closely
adjacent to the bag frame 90. The flexible bag 112 is preferably fabricated by
welding two
sheets of the film material 190 together. One of the sheets forms the portion
of the flexible
bag 112 that is bonded to the first portion 120 of the bag frame 90, while the
other of the
sheets forms a portion of the flexible bag 112 that is bonded to the second
portion 122 of the
bag frame 90.
[000165] Each secondary seal includes a first end 172 and a second end 174,
and is formed
by creating a supplemental heat seal or weld of the two sheets of the film
material 190
together slightly beneath the bag frame 190, as is shown in FIGURE 25. The
first end 172 of
the secondary seal 170 is preferably separated from the bag frame 90 by a
small distance Ds
that is preferably substantially within a range of about 1 mm to about 12 mm,
more preferably
within a range of about 3 mm to about 9 mm and most preferably within a range
of about 4
mm to about 7 mm.
[000166] The film material 190 preferably is fabricated from a material that
substantially
prevents transmission of odors therethrough and that is substantially liquid
impervious. A
preferred embodiment of the film material 190 is diagrammatically shown in
FIGURE 31 and
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includes a first outer layer 192 that defines the outer surface of the
flexible bag 112, a second
layer 194, a third layer 196, a fourth layer 198, a fifth layer 200, a sixth
layer 202, and a
seventh, inner layer 204 that defines the inner surface of the flexible bag
112.
[000167] The film material 190 preferably has a total thickness that is
preferably
substantially within a range of about 15 pm to about 45 pm, and more
preferably substantially
within a range of about 20 pm to about 40 pm.
[000168] The first and seventh external layers 192, 204 are fabricated to
ensure durability
and their ability to be heat sealed together and to the bag frame 90. In
addition, these layers
are preferably fabricated using a slip agent in order to ensure that the
coefficients of friction
are within the predetermined ranges described above. The slip agent, which is
preferably cis-
13-Docosenoamide, CAS NO.: 112-84-5, decreases the engagement between the film
material 190 and the bag-engaging surfaces of the finger members 94 both when
the lower
portion 116 is pushed downwardly by the user through the finger members 94,
and when the
intermediate portion 113 of the bag member 112 is engaged and twisted by the
finger
members 94.
[000169] The first and seventh external layers 192, 204 each both preferably
have a thickness
that is substantially within a range of about 2.75 pm to about 6.75 pm, and
more preferably
substantially within a range of about 3.75 pm to about 5.75 pm. The most
preferable
dimensions are shown in Table 1.
[000170] An anti-block agent is also preferably provided in the external
layers 192, 204 in
order to prevent the film material from sticking together. In the preferred
embodiment a
zeolite, preferably CAS NO: 1318-02-1, is used.
[000171] The second and six layers 194, 202 are fabricated to ensure
durability and
preferably include a pigmentation agent in order to provide a desired
coloration. A slip agent
is also preferably included in these layers 194, 202, which is preferably cis-
13-
Docosenoamide, CAS NO.: 112-84-5.
[000172] The second and six layers 194, 202 each both preferably have a
thickness that is
substantially within a range of about 3.25 m to about 7.25 p,m, and more
preferably
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substantially within a range of about 4.25 um to about 6.25 um. The most
preferable
dimensions are shown in Table 1.
[000173] Alternatively, the second and sixth layers 194, 202 could be
integrated into the first
and seventh outer layers 192, 204 in order to create a five layered material.
In this case, the
thickness of each combined layer would preferably be substantially within a
range of about
8.0 ium to about 12.0 um, and more preferably substantially within a range of
about 9.0 um to
about 11.0 [mi.
[000174] The third and fifth layers 196, 200 are tie layers having the
function of binding the
respective adjacent layers together. Preferably, an anhydride-modified linear
low-density
polyethylene (LLDPE) adhesive resin is used, such as Dupont 41E687. The third
and fifth
layers 196, 200 each both preferably have a thickness that is substantially
within a range of
about 1.75 pm to about 5.75 um, and more preferably substantially within a
range of about
2.75 um to about 4.75 um. The most preferable dimensions are shown in Table 1.
[000175] The fourth, middle layer 198 is a barrier layer that ensures that the
film material
190 is substantially impervious to liquids and odor transmission. It
preferably has a thickness
that is substantially within a range of about 0.50 um to about 4.50 um, and
more preferably
substantially within a range of about 1.50 pm to about 3.50 um. The most
preferable
dimensions are shown in Table 1.
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[000176] The respective layers most preferably have a construction and a
thickness as
described in the following table:
TABLE 1
Thickness (urn / inch / % of
Base Material
total)
1st layer 66.0% mLLDPE + 30.0% LDPE + 3.8% slip agent
(Outer + 0.2% anti-block agent by weight 4.75um / 0.00019" / 15.8%
layer)
-mLLDPE is preferably ExxonMobil 1018FA
-LDPE is preferably ExxonMobil LD100 series
-Slip agent is preferably cis-13-Docosenoamide,
CAS NO.: 112-84-5
- Anti-block agent is preferably Zeolite, CAS NO:
1318-02-1
2nd layer 66.3% mLLDPE + 28.5% LDPE + 3.8% slip agent 5.25um / 0.00021" /
17.5%
+ 1.4% colorant by wt
-mLLDPE is preferably ExxonMobil 1018FA
-LDPE is preferably ExxonMobil LD100 series
-Slip agent is preferably cis-13-Docosenoamide,
CAS NO.: 112-84-5
-Colorant is preferably SPEM-5M1629
3rd layer Tie layer 3.75um / 0.00015" / 12.5%
Preferably a anhydride-modified linear low-density
polyethylene (LLDPE) adhesive resin, most
preferably Dupont 41E687
4th layer Barrier layer. 2.5um / 0.0001" / 8.4%
Preferably EVOH, most preferably
Nippon Gohsei ET3803
5th layer Tie layer 3.75um / 0.00015" / 12.5%
Preferably a anhydride-modified linear low-density
polyethylene (LLDPE) adhesive resin, most
preferably Dupont 41E687
6th layer 66.3% mLLDPE + 28.5% LDPE + 3.8% slip agent 5.25um / 0.00021" /
17.5%
+ 1.4% colorant by wt
-rriLLDPE is preferably ExxonMobil 1018FA
-LDPE is preferably ExxonMobil LD100 series
-Slip agent is preferably cis-13-Docosenoamide,
CAS NO.: 112-84-5
-Colorant is preferably SPEM-5M1629
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7th layer 66.0% mLLDPE + 30.0% LDPE + 3.8% slip agent 4.75um / 0.00019" /
15.8%
(Inner + 0.2% anti-block agent by weight
layer)
-mLLDPE is preferably ExxonMobil 1018FA
-LDPE is preferably ExxonMobil LD100 series
-Slip agent is preferably cis-13-Docosenoamide,
CAS NO.: 112-84-5
- Anti-block agent is preferably Zeolite, CAS NO:
1318-02-1
[000177] It is to be understood, however, that even though numerous
characteristics and
advantages of the present invention have been set forth in the foregoing
description, together
with details of the structure and function of the invention, the disclosure is
illustrative only,
and changes may be made in detail, especially in matters of shape, size and
arrangement of
parts within the principles of the invention to the full extent indicated by
the broad general
meaning of the terms in which the appended claims are expressed.
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