US20110099950A1 - System and method for disposing waste packages such as diapers - Google Patents

Abstract

Systems and methods for facilitating hygienic storage and disposal of waste packages such as used disposable diapers include a housing, a lid, and a bag unit having a bag frame and an attached single use flexible bag. The flexible bag is pleated and larger in cross-section at a lower portion than it is at the connection to the bag frame. The bag frame is releasably mounted to the housing so that it will not rotate. The lower portion of the flexible bag is positioned in a storage chamber of the housing that is shaped so as to align and center the bag. A rotatable member having radially extending flexible fingers is engaged with an intermediate portion of the bag. When the lid is closed, the rotatable member will twist the intermediate portion of the bag, sealing odors in the lower portion of the bag. A parent or caregiver will push the waste package through the resistance of the twisted intermediate portion into the lower portion of the bag, and close the lid to re-seal the twisted portion.

Description

BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• 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
• 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.
• 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.
• One such system has been marketed under the trademark DIAPER GENIE®. The original DIAPER GENIE® 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 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.
• 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.
• Another version of the DIAPER GENIE® 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.
• Unfortunately, the pressure that is created by the spring-loaded jaws in the second version of the DIAPER GENIE® 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.
• 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.
• Another type of waste disposal system has been invented by Mr. David Stravitz and is disclosed in U.S. Pat. Nos. 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.
• 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 U.S. patent application Ser. Nos. 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.
• 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.
SUMMARY OF THE INVENTION
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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 bag, and wherein the rotatable member comprises a support member for supporting the bag frame.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 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;
• FIG. 2 is a second perspective view depicting the diaper pail assembly that is shown inFIG. 1, shown in a closed position;
• FIG. 3 is a side elevational view depicting the diaper pail assembly that is shown inFIG. 1;
• FIG. 4 is a fragmentary cross-sectional view depicting a portion of the diaper pail assembly that is shown inFIG. 1;
• FIG. 5 is another fragmentary cross-sectional view depicting a portion of the diaper pail assembly that is shown inFIG. 1;
• FIG. 6 is a side elevational view depicting the diaper pail assembly that is shown inFIG. 1, shown in a closed position;
• FIG. 7 is a top plan view depicting the diaper pail assembly that is shown inFIG. 6;
• FIG. 8 is a bottom plan view showing the diaper pail assembly that is shown inFIG. 6;
• FIG. 9 is a second side elevational view showing the diaper pail assembly that is shown inFIG. 6;
• FIG. 10 is a front elevational view depicting the diaper pail assembly that is shown inFIG. 6;
• FIG. 11 is a rear elevational view depicting the diaper pail assembly that is shown inFIG. 6;
• FIG. 12 is a fragmentary perspective view depicting a transmission mechanism within the diaper pail assembly that is shown inFIG. 1;
• FIG. 13 is a fragmentary perspective view depicting another portion of the transmission mechanism shown inFIG. 12;
• FIG. 14 is a fragmentary cross-sectional view depicting another portion of the transmission mechanism shown inFIG. 12;
• FIG. 15 is a fragmentary cross-sectional view depicting another portion of the diaper pail assembly that is shown inFIG. 1;
• FIG. 16 is a fragmentary perspective view depicting a portion of the diaper pail assembly that is shown inFIG. 1;
• FIG. 17 is a top plan view of one component of the diaper pail assembly that is shown inFIG. 1;
• FIG. 18 is a cross-sectional view taken along lines18-18 inFIG. 17;
• FIG. 19 is a cross-sectional view taken along lines19-19 inFIG. 17;
• FIG. 20 is a diagrammatical depiction of the diaper pail assembly shown inFIG. 1 in use;
• FIG. 21 is a top plan view of a diaper pail bag assembly that is constructed according to the preferred embodiment of the invention;
• FIG. 22 is a bottom plan view of the diaper pail bag assembly that is shown inFIG. 21;
• FIG. 23 is a cross-sectional view taken along lines23-23 inFIG. 22;
• FIG. 24 is a cross-sectional view taken along lines24-24 inFIG. 22;
• FIG. 25 is a fragmentary depiction of the diaper pail bag assembly shown inFIG. 21 in a closed position;
• FIG. 26 is a diagrammatical cross-sectional view taken along lines26-26 inFIG. 25;
• FIG. 27 is an isolation view of one component of the diaper pail bag assembly shown inFIG. 21;
• FIG. 28 is an exploded cross-sectional view taken along lines28-28 inFIG. 25;
• FIG. 29 is an exploded cross-sectional view taken along lines29-29 inFIG. 25; and
• FIG. 30 is an exploded cross-sectional view taken along lines30-30 inFIG. 25; and
• FIG. 31 is a diagrammatical depiction of the film material that is used in the diaper pail bag assembly shown inFIG. 21.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
• Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views, and referring in particular toFIG. 1, a diaper pail assembly orsystem10 that is constructed according to a preferred embodiment of the invention includes ahousing12 and alid member14.Lid member14 is connected to thehousing12 by ahinge mechanism16 so that thelid member14 can be moved by a parent or caregiver between an open position that is shown inFIG. 1 and a closed position that is shown inFIG. 2.
• Housing12 defines aninterior storage space13, best shown inFIG. 5, which can be accessed by a parent or a caregiver by opening adoor18. Thedoor18 is hingedly mounted with respect to thehousing12.Diaper pail assembly10 further includes abase portion20 that is constructed and arranged to support thehousing12 on an underlying horizontal surface such as a floor or a carpet.
• A latching mechanism andgripping knob22 is provided on thedoor18 for permitting the consumer to open and close thedoor18 in conventional fashion. The latching mechanism andgripping knob22 further includes a latch mechanism of conventional design that interengages with a portion of thehousing12 in order to selectively lock thedoor18 in a closed position as shown inFIG. 1. Thedoor18 is also preferably provided with a mechanism for releasably retaining thedoor18 in the open position, so that thedoor18 will not swing shut at a time that is inconvenient for the consumer.
• Alid latching mechanism24 includes a laterallyexpandable latch member26 that is movably mounted on thelid member14 and amating recess28 that is defined in thehousing12. Referring briefly toFIG. 4, a button or actuatingsurface30 is movably mounted on a side of thelid member14 that is opposite thehinge mechanism16 and is constrained with respect to thelid member14 so as to permit only substantially vertically upward and downward movement with respect to thelid member14. A slottedplunger member32 is integral with an underside of theactuating surface30 and is constructed and arranged to cam against outer cam surfaces25 of an opposed pair of pivotally mounted laterallyexpandable latch members34,36 when theactuating surface30 is depressed by a consumer.Latch members34,36 are biased by an internal spring towards the open position that is shown inFIG. 4.
• When a consumer closes thelid member14, curvedlower services27 of thelatch members34,36 cam thelatch members34,36 inwardly, permitting the recessed surfaces29 of therespective latch members34,36 to engage with the surface on thehousing12 that defines therecess28. 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 apowder dispensing assembly40 that is mounted to amating receptacle42 that is secured to the underside of thelid member14, best shown inFIG. 1.
• Thepowder dispensing assembly40 and its method of operation is preferably constructed as described in co-pending U.S. patent application Ser. No. 12/609,136, filed Oct. 30, 2009, the entire disclosure of which is hereby incorporated by reference as if set forth fully herein.
• Powder dispensing assembly40 is preferably constructed and arranged to dispense a deodorizing or odor-absorbing powder such as sodium bicarbonate into a targeted area of thediaper pail assembly10. It preferably includes a directional dispensing mechanism including an orifice for dispensing powder from theassembly40 in such a manner that initial dispersal of the powder is concentrated to a single side of thepowder dispensing assembly40 that is preferably away from thehinge mechanism16.
• When a consumer desires to open thelid member14 of thediaper pail assembly10 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 theactuator button30, which will drive theplunger32 downwardly, causing theplunger32 to contact the outer cam surfaces25 of therespective latch members34,36. This will cause thelatch members34,36 to disengage from therecess28 and enable thelid member14 to be lifted upwardly.
• An undercut31 or recess is preferably defined in thehousing12 on an opposite side ofhousing12 from thehinge mechanism16 in order to give the consumer space to be able to exert lifting pressure on a liftingsurface33 of thelid member14, as may be visualized by viewingFIG. 1. This will enable a parent or caregiver to easily lift thelid member14 after thelid latching mechanism24 has been disengaged.
• Referring now toFIG. 5,diaper pail assembly10 advantageously includesstructure44 for aligning and centering a diaper pail bag within theinterior storage space13 of thehousing12. In the preferred embodiment, the aligning and centeringstructure44 includes abottom surface46 defining a lowermost extent of theinterior storage space13 that includes a central, substantiallyflat portion48 and an annularcurved portion50 surrounding the substantiallyflat portion48.
• Alternatively, thebottom surface46 could be entirely concavely curved, or the central portion could even have a slight convex curvature. Theportion50 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 thecentral portion46 and generally annular.
• The central substantiallyflat portion48 is preferably substantially circular in shape as viewed in top plan and has a maximum radius R₁that 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 mm and most preferably within a range of about 45 mm to about 85 mm. Alternatively, thecentral portion48 could have a generally oval shape as viewed in top plan.
• The annularcurved portion50 occupies a substantial portion of thebottom surface46 and is substantially concave, having an average radius of curvature R₂that is preferably within a range of about 15 mm to about 120 mm. More preferably, the average radius of curvature R₂of the annularcurved portion50 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.
• In terms of surface area, the curvedconcave portion50 is preferably substantially at least 25% of thebottom surface46 as a whole, more preferably substantially at least 40% of the surface area of thebottom surface46 and most preferably substantially at least 60% of the surface area of thebottom surface46.
• Thebottom surface46 may additionally include a smallupper ledge portion52 at its extreme outer periphery, connected to the annularconcave portion50 by a concave portion that is shaped to provide a smooth transition between the annularconcave portion50 and theupper ledge portion52. Theentire bottom surface46 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.
• A ratio R₂/R₃is 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.
• Thebottom surface46 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.
• Thebottom surface46 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.
• Thebottom surface46 and the external surface of theflexible bag112 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.
• Thebottom surface46 and the external surface of theflexible bag112 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.
• The presence of the annularconcave portion50 has a beneficial effect of aligning and centering the diaper pail bag in order to enhance the effectiveness of thetwist seal120 that will be described in greater detail below and to optimize the space efficiency within theflexible bag112 and within theinternal storage space13.
• As can be visualized by viewingFIG. 20, the sloped walls of theannular portion50 will direct the center of mass of alower portion116 of theflexible bag112 radially inwardly toward a longitudinal axis of thehousing12 of thediaper pail assembly10. As waste packages118 are inserted into thelower portion116 of theflexible bag112, the resulting expansion will tend to occur radially outwardly and evenly in all directions, thus taking advantage of theentire storage space13 within thehousing12 in a space-efficient manner. As a result, more diapers may be stored within thediaper pail assembly10 before it needs to be emptied than would otherwise be the case.
• Diaper pail assembly10 further preferably includes a rotatable sealing and grippingmember54 that is constructed and arranged to create a restricted portion within the flexiblediaper pail bag112 in order to provide a temporary odor seal. In the preferred embodiment, this is accomplished by gripping and twisting the flexiblediaper pail bag112 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 theflexible bag112 instead of by twisting it.
• Atransmission mechanism56 is provided for causing rotation of therotatable sealing member54 for a predetermined rotational distance when thelid member14 is moved from the open position shown inFIG. 1 to the closed position shown inFIG. 2.Transmission mechanism56 includes apush rod member58, visible in FIGS.1 and12-14, that is caused and constrained to slide linearly downwardly when thelid member14 is closed and linearly upwardly when it is opened.Transmission mechanism56 is designed so as not to cause any movement of therotatable sealing member54 when thelid member14 is pivoted upwardly from the closed position to the open position.
• Preferably,transmission mechanism56 is constructed and arranged to cause therotatable sealing member54 to rotate a predetermined angular distance when thelid member14 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.
• Transmission mechanism56 is depicted in greater detail inFIGS. 12-14. In the preferred embodiment, thepush rod member58 includes atoothed rack portion60 that is best visible inFIG. 13. Thepush rod member58 is constrained to permit only vertical movement thereof with respect to thehousing12 by a slotted channel within theinternal housing frame70. Arack engaging gear59 is mounted for rotation with respect to theinternal housing frame70 in such a manner that it is permitted a limited amount of vertical movement with respect to theinternal housing frame70. Rack engaginggear59 has teeth that are operatively engaged with corresponding teeth on thetoothed rack portion60 when therack engaging gear59 is in its lowermost vertical position.
• Transmission mechanism56 further includes asecond compound gear62 having afirst gear portion68 and asecond gear portion69 that have common axes of rotation and are joined for common movement except when a predetermined transmission force therebetween is exceeded, when aclutch mechanism63 will incrementally permit relative angular displacement therebetween in order to relieve internal forces within thetransmission mechanism56 and avoid damage to thediaper pail assembly10.
• Thefirst gear portion68 is operatively engaged with therack engaging gear59, and thesecond gear portion69 is operatively engaged with athird compound gear65 having afirst gear portion66 and asecond gear portion67. Thethird compound gear65 is formed so that the first andsecond gear portions66,67 are integrally formed and are mounted for common rotation about a common axis. Thefirst gear portion66 of thethird compound gear65 is in operative engagement with thesecond gear portion69 of thesecond compound gear62. Thesecond gear portion67 of thethird compound gear65 is in operative engagement with atoothed rack portion82 that is formed on an underside of a rotatable flexible bag retaining and sealingmember54 that will be discussed in greater detail below.
• When thelid member14 is pivoted downwardly by a parent or caregiver from the open position that is shown inFIG. 1 to the closed position that is shown inFIG. 2, thepush rod member58 will be driven downwardly and the rotatable flexible bag retaining and sealingmember54 will be driven by thegear train mechanism61 to rotate for the predetermined angular distance, thereby creating atwisted portion120 in anintermediate portion113 of theflexible bag112 that is between a lower orbottom portion116 and anupper portion114. This is diagrammatically shown inFIG. 20.
• Thegear train mechanism61 is operatively interconnected when thepush rod member58 moves downwardly, because therack engaging gear59 is in its lowermost vertical position and operatively engaged with thesecond compound gear62. However, when thelid member14 is pivoted upwardly from the closed position to the open position, therack engaging gear59 is lifted upwardly out of engagement with thesecond compound gear62. Accordingly thegear train mechanism61 will be disengaged and there will be no rotation of the flexible bag retaining and sealingmember54 when thelid member14 is opened, which allows the twisted bag to remain closed.
• As may be visualized by viewingFIG. 20, the motion of pushing thewaste package118 downwardly through thetwisted portion120 may have the temporary effect of reducing the degree of twist in thetwisted portion120. However, when thelid member14 is closed, the amount of twist in thetwisted portion120 is increased, which reinforces the quality of the odor seal that is created by thetwisted portion120.
• In the event that thegear train mechanism61 becomes jammed, internal forces within thegear train mechanism61 will cause theclutch mechanism63 to permit a relative amount of relative movement between thefirst gear portion68 and the second gear portion of thesecond compound gear62.Clutch mechanism63 includes two relatively slidable components that are biased together by aspring member64, best shown inFIG. 14, which is operatively interposed between thesecond compound gear62 and theinternal housing frame70.
• Referring now toFIG. 16, the flexible bag retaining and sealingmember54 preferably includes amain body portion71 having anouter flange72 that defines anupper surface74, which is preferably substantially flat. Alternatively, theupper surface74 could be shaped so that it is slightly convex. A plurality of retainingmembers76 are defined as projections that are integral with aportion78 of theinternal housing frame70. These are constructed and arranged to vertically constrain the flexible bag retaining and sealingmember54 so that is permitted to rotate with respect to theinternal housing frame70 but is precluded from upward vertical movement.
• The retainingmembers76 and theupper surface74 of theouter flange72 are preferably constructed and arranged to minimize relative friction therebetween. The relative kinetic coefficient of friction between the retaining members and theupper surface74 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.
• The relative static coefficient of friction between the retaining members and theupper surface74 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.
• In addition, alower surface80 of theouter flange72 is supported for low friction rotation with respect to theinternal housing frame70 by a plurality of bearingmembers77, as is best shown inFIG. 15. In the preferred embodiment, the bearingmembers77 are positioned to bear against a lower surface of a lowerouter flange projection73 of theouter flange72.Bearing members77 are preferably fabricated out of a material having a relatively low coefficient of friction, such as nylon, polytetrafluoroethylene (PTFE) or polyoxymethylene (POM). Most preferably, bearingmembers77 are fabricated from POM.
• FIG. 15 also shows that thehousing12 preferably has afinger access recess75 defined therein for permitting a parent or caregiver to place a finger against thelower surface88 of thebag frame90 in order to prise thebag frame90 upwardly in order to disengage it from thehousing12. The consumer will perform such an action when removing theflexible bag assembly110 from thediaper pail assembly10. The inherent flexibility of thebag frame90 permits thebag frame90 to be elastically deformed to the extent that is necessary to remove it from thehousing12 in this manner.
• Referring again toFIG. 16, themain body portion71 of the flexible bag retaining and sealingmember54 preferably includes anupper flange portion84 having a narrow, convexly curvedupper surface86 that defines a low friction surface for supporting alower surface88 of abag frame90 that is part of aflexible bag assembly110.
• Theupper surface86 of theupper flange portion84 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 sealingmember54 can simultaneously perform the function of supporting the underside of thebag frame90 while being able to freely rotate with minimal friction. Theflexible bag assembly110 will be described in greater detail below.
• Themain body portion71 of the flexible bag retaining and sealingmember54 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 sealingmember54 further includes a radially innerresilient portion92 including a plurality of inwardly extendingresilient finger members94 that are configured to operatively interact with theflexible bag112 in a complex manner that includes engaging theintermediate portion113 of theflexible bag112 to create atwisted portion120 in order to effectively seal odors within thelower portion116 of theflexible bag assembly110 during use. This may be visualized by viewingFIG. 20.
• The innerresilient portion92 of the flexible bag retaining and sealingmember54 is also constructed in such a manner to make it easy for a parent or caregiver to push thelower portion116 of thebag assembly110 through the central portion of the innerresilient portion92 during initial installation of aflexible bag assembly110 into thediaper pail assembly10. This is achieved through a combination of the unique shape of the individualresilient finger members94, the shape of the spaces orslots95 that are defined between theindividual finger members94 and the degree of elasticity and frictional characteristics of both thefinger members94 and the outer and inner surfaces of theflexible bag112.
• FIG. 17 is a top plan view of a flexible bag retaining and sealingmember54 that is constructed according to a preferred embodiment of the invention. In this embodiment, sixresilient finger members94 are spaced about an inner periphery of themain body portion71 and extend radially inwardly to acentral opening96. Six spaces orslots95 are respectively defined between theadjacent finger members94, with each of thefinger members94 andspaces95 having substantially the same shape and dimensions in the preferred embodiment. Alternatively, the shape of thefinger members94 and theslots95 could be varied.
• Each of thefinger members94 includes a distal, radially innermost end portion terminating at a convexly radiusedtip101 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, theconvexly radius tips101 are shaped to have radius of curvature that is substantially within a range of about 0.9 mm to about 1.9 mm.Tip portion101 is also preferably thickened with respect to adjacent portions of theflexible fingers94, as is discussed below.
• The convexly radiusedtips101 of therespective finger members94 together define thecentral opening96, which preferably has a minimum diameter D₁that 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 D₁is substantially within a range of about 6 mm to about 10 mm.
• Each of thefinger members94 is also preferably shaped so as to have a pair of side edges98,100, each of which is curved and preferably slightly concave so that each of the spaces defined by a pair of the opposing side edges98,100 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 edges98 is preferably substantially within a 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 edges98,100 can be substantially constant, or it can alternatively be variable or formed of two or more compound curves.
• AsFIG. 17 shows, thefinger members94 are preferably shaped and sized so that at least one of thespaces95, when in an unstressed position, has a first width W₁at afirst location102, which is preferably at an intermediate radial location along thefinger members94 where the width of thespace95 is at a maximum. Preferably, thefirst location102 is located substantially at a radial midpoint of the opposingadjacent finger members94. Eachspace95 further has a second width W₂at asecond location104, which is preferably near the distal end of therespective finger members94 where the width is at a minimum. The first width W_iis preferably greater than the second width W₂.
• Thespace95 further has a third width W₃defined at athird location106 that is preferably near the radially outermost, proximal end of therespective finger members94 where the width is at a minimum. The first width W₁is preferably greater than the third width W₃.
• The first, second andthird locations102,104,106 are accordingly radially spaced from each other, with thefirst location102 being radially intermediate between the second andthird locations104,106.
• The first width W₁is 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.
• The second width W₂is 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.
• A ratio of the first width W₁to the second width W₂is 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.
• The third width W₃is 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.
• A ratio of the first width W₁to the third width W₃is 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.
• FIGS. 18 and 19 are cross-sectional views taken along lines18-18 and19-19, respectively, inFIG. 17. These figures show that each of theresilient finger members94 includes anupper surface97 that is curved concavely with a varying radius of curvature so that the radially outermost portion between the first andthird locations102,106 as viewed inFIG. 17 has a smaller radius of curvature and is therefore more curved than the radially innermost portion between the first andsecond locations112,104. Accordingly, each of theresilient finger members94 initially curves downwardly from its proximal connection to themain body portion71 and then flattens out, extending substantially horizontally from its intermediate portion to its most distal portion. The lower surfaces99 accordingly have a convex curvature that is more pronounced in the proximal portion of thefinger94 than in the distal portion.
• The lower surfaces99 of each of the respectiveresilient finger members94 are also preferably spaced from theupper surface97 so that each of thefinger members94 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.
• The distal, radiallyinnermost tip portions101 of thefinger members94 are preferably slightly thickened with respect to the adjacent blade portions, as is best shown inFIG. 19. The thickenedtip portions101 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.
• Theresilient finger members94 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 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.
• The material from which theresilient finger members94 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.
• In addition, at least the portions of each of theresilient finger members94 that will contact theflexible bag112 preferably has a static coefficient of friction with respect to the external surface of theflexible bag112 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 theflexible bag112 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.
• The external surface of theflexible bag112 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.
• The internal surface of theflexible bag112 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.
• FIG. 20 is a diagrammatical depiction of adiaper pail assembly10 that is constructed according to the preferred embodiment of the invention, shown in operation. Abag assembly110 having abag frame portion90 that is attached to anupper portion114 of aflexible bag112 is installed by a parent or caregiver into thediaper pail assembly10 by seating thebag frame90 into thehousing12 of thediaper pail assembly10 in a manner that will be described in greater detail below.
• The parent or caregiver will then push thelower portion116 of theflexible bag112 downwardly into theinternal storage space13 of thehousing12 by pushing it through the resilientflexible fingers94 of the flexible bag retaining and sealingmember54. Thelid member14 is then closed, which causes the flexible bag retaining and sealingmember54 to rotate by a predetermined angular distance to create atwisted portion120 in theintermediate portion113 of theflexible bag112.
• The parent or caregiver will use thediaper pail assembly10 by inserting awaste load package118 such as a used disposable diaper into thelower portion116 of theflexible bag112 by pushing it downwardly through thetwisted portion120 of theintermediate portion113 of theflexible bag112. This is performed against the resistance bias that is applied by the resilience of theresilient finger members94. As the parent or caregiver pushes thewaste load package118 downwardly through thetwisted portion120, the tapered, leaf-like pattern of eachresilient finger member94 andspace95 helps thebag112 slide along theopposed edges98,100 that define thespace95. In addition, when thelid member14 is closed, the tapered, leaf-like pattern of eachresilient finger member94 andspace95 helps to reduce drag between thebag112 and the flexible bag retaining and sealingmember54.
• Thebottom portion116 of theflexible bag122 is not expected to move substantially with respect to thehousing12 during the creation of thetwisted portion120, particularly when it is weighted down by a number of waste packages118. Accordingly, the degree of twist that is created in theflexible bag112 by the rotation of the retaining and sealingmember54 when thelid member14 is closed is expected to be comparable and at least equal to the predetermined amount of angular rotation of the retaining and sealingmember54. In practice, the degree of twist in theflexible bag112 will be more than the predetermined amount of angular rotation of the retaining and sealingmember54 after insertion of thesecond waste package118, because a certain amount of residual twisting will remain in thetwisted portion120 even after thefirst waste package118 is pushed through thetwisted portion120.
• As is described in greater detail below with reference toFIG. 31, both the external and internal surfaces of theflexible bag112 is also preferably treated with a friction reducing slip agent in order to further reduce drag between thebag112 and the flexible bag retaining and sealingmember54. 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 packages118.
• As the consumer pushes thewaste load package118 downwardly through thetwisted portion120, the inherent resilience of theflexible bag112 at thetwisted portion120 in conjunction with the inward resilient bias that is imparted to the outer surface of theflexible bag112 by theresilient finger members94 keep the outermost portions of thewaste package118 tightly against the inner surface of theflexible bag112, which maintains an effective odor seal even during insertion of thewaste package118 into thelower portion116 of theflexible bag112. This minimizes leakage of odor from thelower portion116 of theflexible bag12 through thetwisted portion120 where it could be detected by the parent or caregiver.
• When thelid member14 is closed, powder material such as sodium bicarbonate is dispensed from thepowder disperser40 into theupper portion114 of theflexible bag112, above the twistedintermediate portion113. The powder material is retained in theupper portion114 above the twistedintermediate portion113 of theflexible bag112 for a period of time before a portion of it is swept by the parent or caregiver into thelower portion116 of the flexible bag as the parent of caregiver pushes awaste package118 downwardly through the twistedintermediate portion113. The powder material accordingly deodorizes or absorbs odor in the upper area of thediaper pail assembly10 for a period of time when it is positioned within theupper portion114 of theflexible bag112, and later in thelower portion116 of theflexible bag112.
• The process of pushing awaste package118 such as a wrapped, used disposable diaper through the intermediate,twisted portion113 of theflexible bag112 is facilitated by the low static and kinetic frictional characteristics of theinnermost layer204 of thefilm material190, shown inFIG. 31. Moreover, the presence of the powder material provides additional lubrication to the inner surface of theflexible bag122 in the area of the twistedintermediate portion113.
• 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.
• The powder material also preferably has a bulk density that is substantially within a range of about 48 lb/ft³to about 78 lb/ft³, more preferably within a range of about 53 lb/ft³to about 73 lb/ft³and most preferably within a range of about 58 lb/ft³to about 68 lb/ft³.
• FIG. 21 is a top elevational view of aflexible bag assembly110 that is constructed according to a preferred embodiment of the invention.Flexible bag assembly110 includes aflexible bag112 that is preferably pleated so as to permit thelower portion116 of theflexible bag112 to expand to a cross-sectional area that is greater than the cross-sectional area of theflexible bag112 at its point of attachment to thebag frame90.
• Bag frame90 is preferably fabricated from a plastic material such as high density polyethylene, and includes afirst portion120 that is generally semicircular in shape and asecond portion122 that is also generally semicircular in shape.
• Bag frame90 defines anupper surface121, as is shown inFIG. 21, and alower surface88 that is best shown inFIG. 22.Bag frame90 is preferably constructed so as to be foldable about ahinge portion124 from the open position that is shown inFIGS. 21 and 22 to the closed position that is shown inFIG. 25. In the closed position that is shown inFIG. 25, the closure of thebag frame90 effectively closes theupper portion114 of theflexible bag112 and prevents odors from escaping from theflexible bag112.
• In addition, thebag frame90 when in the closed position forms a convenient handle that is shaped and sized for a consumer to conveniently grip in order to carry theflexible bag112, together with any waste load packages118 that are stored therein, to a location that is remote from thediaper pail assembly10 for final disposal of theflexible bag112 and the waste load packages118.
• Referring back toFIG. 21, thehinge portion124 is preferably integrally molded into thebag frame90 and is formed as a linear area that has a reduced cross-sectional thickness, so as to permit folding of thebag frame90 into the closed position. Thebag frame90 further includes an annularinner surface126 that defines acentral opening128 that forms the open end of thebag frame assembly110 when thebag frame90 is in the open position. Thecentral opening128 is preferably substantially circular and preferably has a maximum inner lateral dimension or diameter D_ithat 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 mm to about 150 mm.
• Bag frame90 also preferably is constructed to have an outercircumferential surface130 that is preferably substantially circular in shape and that defines a minimum outer diameter D_othat is preferably within a range of about 90 mm 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.
• The inner diameter D_irepresents a first diameter of theflexible bag112 at a location proximate theframe90. Theflexible bag112 at itslower portion116 further includes a second diameter D_Lthat is preferably the maximum diameter of the entireflexible bag112. The second diameter D_Lis depicted inFIG. 20, and should properly be measured for purposes of this document with thelower portion116 of thebag112 expanded to the maximum extent permitted by the construction of thebag122 in a shape that is circular in transverse cross-section. Preferably, the second diameter D_Lis larger than the first diameter D_i.
• The second diameter D_Lis 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.
• A ratio of the first diameter D_ito the second diameter D_Lis 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.
• Theflexible bag assembly110 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.
• A plurality of male, radially outwardly extendingprojections132,134,136,138 are preferably integrally formed in thebag frame90 for permitting secure registration of thebag frame90 with respect to thehousing12 of thediaper pail assembly10 during use. Referring back briefly toFIG. 16, a plurality ofrecesses133 are defined in thehousing12 for receiving therespective projections132,134,136,138 in such a manner that thebag frame90 is secured against rotation relative to thehousing12 and is securely oriented and aligned in a horizontal position when theprojections132,134,136,138 are received within therespective recesses133.
• In addition, structure that is embodied as a retainingprojection135 is preferably provided in each of therespective recesses133 for releasably locking therespective projection132,134,136,138 within therespective recess133. The retainingprojections135 are preferably fabricated from a substantially rigid plastic material and are integral with thehousing12 of thediaper pail assembly10. The inherent flexibility of the material from which thebag frame90 is fabricated permits the parent or caregiver to manipulate thebag frame90 into the secured position wherein each of theprojections132,134,136,138 are positioned beneath therespective retaining projections135. Similarly, the inherent flexibility of thebag frame90 is utilized when removing thebag frame90 from thehousing12.
• Releasable locking structure140 is also preferably provided on thebag frame90 in order to permit the parent or caregiver to releasably lock thebag frame90 into the closed position that is shown inFIG. 25. In the preferred embodiment, thereleasable locking structure140 includes a curvedfemale recess142 that is defined in thefirst portion120 of thebag frame90 and a mating curvedmale projection144 that is defined in thesecond portion122 of thebag frame90. Thecurved mating portions142,144 advantageously and preferably extend along most of the outer periphery of therespective portions120,122 of thebag frame90 in order to effectively retain odors within theflexible bag assembly110 when it is in the closed position shown inFIG. 25.
• Thereleasable locking structure140 accordingly is constructed and arranged to define an effective odor seal as well as a locking mechanism to retain thebag frame90 in the closed position. Thecurved mating portions142,144 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 150° to about 179°. The larger the angular distance covered by thecurved mating portions142,144, the more effective odor seal will be created by thereleasable locking structure140.
• As is shown inFIG. 22, which is a bottom plan view of thebag frame90 shown in the open position, the male, radially extendingprojections132,134,136,138 are preferably staggered about the outer periphery of thebag frame90 so that the projection pairs134,138 and132,136 are adjacent to each other but do not fully overlap when in the closed position shown inFIG. 25. In the preferred embodiment, theprojections132,134,136,138 are spaced so that there is a slight but not full overlap between the corresponding projection pairs134,138 and132,136. This permits the parent or caregiver to use his or her thumb and forefinger in order to gain leverage against one of the projection pairs134,138 or132,136 in order to disengage thereleasable locking structure140 and move thebag frame90 from the closed position into the open position.
• AsFIG. 22 shows, each of theprojections132,134,136,138 is preferably constructed so as to have an outer surface that is convexly about aradial center locus147. Theradial center locus147 of theprojection134 is preferably spaced a first distance L₁from a vertical transverse centerline of thebag frame90 and a second distance L₂from a horizontal transverse centerline as viewed in bottom plan as shown inFIG. 22. Theradial center locus147 of theprojection132 is preferably spaced by the second distance L₂from the vertical transverse centerline and by the first distance L₁from the horizontal centerline. Theprojection138 is preferably spaced by the first distance L₁from the horizontal centerline and by the second distance L₂from the vertical centerline, and theprojection136 is preferably spaced by the first distance L₁from the vertical centerline and by the second distance L₂from the horizontal centerline.
• Preferably, the first distance L₁is less than the second distance L₂. More preferably, the first distance L₁has a ratio with respect to the second distance L₂that 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 L₁could be greater than the second distance L₂.
• Referring now toFIG. 23, it will be seen that the femalecurved mating portion142 of thereleasable locking structure140 preferably has asmall projection150 defining an undercut for receiving and retaining the malecurved mating portion144 in the locked position. AsFIG. 24 shows, the malecurved mating portion144 also preferably includes aprojection148 for engaging theprojection150 in the femalecurved mating portion142. The female andmale mating portions142,144 are shown in the secured positions inFIGS. 28-30.
• Theupper portion114 of theflexible bag112 has a complex and advantageous construction in order to ensure secure attachment to thelower surface88 of thebag frame90. It is preferably die cut in order to correspond to the shape of thebag frame90.
• Referring toFIGS. 22 and 25, it will be seen that afilm reinforcement insert154 is bonded to a portion of thelower surface88 that includes areas of the first andsecond portions120,122 as well as thehinge portion124. Thefilm reinforcement insert154 is preferably fabricated from a film material that is substantially identical in construction to the film material from which theflexible bag112 is fabricated. It increases the strength of the seal that is formed between theupper portion114 of the flexible bag in thelower surface88 of thebag frame90. It also provides the additional benefit of providing some reinforcement to thehinge portion124.
• Thefilm reinforcement insert154 is shown in isolation inFIG. 27 and includes afirst portion156 that is bonded to thefirst portion120 of thebag frame90, as shown inFIG. 22, and asecond portion160 that is bonded to thesecond portion122 of thebag frame90. Thefilm reinforcement insert154 is preferably tacked or heat sealed to thelower surface88 using a hot tool such as a hot tip soldering iron prior to the assembly of theupper portion114 of theflexible bag112 to thebag frame90.
• Theupper portion114 of theflexible bag112 further preferably includes aprimary seal portion162 that is bonded, tacked or heat sealed to a semicircular portion of each of the first andsecond portions120,122 of the bag frame91 on thelower surface88. Theprimary seal portion162 is integral with theupper portion114 and includes afirst end164, an oppositesecond end166 and a curvedcentral portion168. The first and second ends164,166 preferably respectively have broadened end portions that in the preferred embodiment are substantially circular. The first and second ends164,166 are bonded by heat sealing to the respective film reinforcement inserts154, which enhances the strength of the ultimate bond between the first and second ends164,166 and theunderside88 of thebag frame90.
• Referring briefly toFIG. 26, which is a diagrammatical cross-sectional view taken along lines26-26 inFIG. 25, theupper portion114 of theflexible bag112 is advantageously pleated in order to permit significant expandability of thelower portion116 of theflexible bag112 with respect to theupper portion114. The pleating is constructed and arranged in such a manner in the preferred embodiment that eachpleat176 includes threeplies182,184,186 of thefilm material190 from which theflexible bag112 is fabricated, with afirst fold178 being defined between the first andsecond plies182,184 and asecond fold180 being defined between the second andthird plies184,186. Each of thepleats176 is preferably substantially parallel to adjacent pleats and is preferably oriented so as to extend parallel to a longitudinal axis of theflexible bag assembly110 that is substantially perpendicular to the transverse plane in which thebag frame90 is positioned during use.
• Theflexible bag112 preferably includes at least twopleats176 around the outer periphery, more preferably at least fourpleats176 and most preferably at least sixpleats176. In the illustrated embodiment, theflexible bag112 has eightpleats176.
• FIG. 28 is an exploded cross-sectional view taken along lines28-28 inFIG. 25. Theprimary seal162 is constructed and arranged so that all three plies of theupper portion114 are bonded to each other, with the inwardmost ply182 being directly bonded to thelower surface88 of thebag frame90. This is also shown inFIG. 29, which is an exploded cross-sectional view taken along lines29-29 andFIG. 25.FIG. 30 is an exploded cross-sectional view taken along lines30-30 inFIG. 25, showing a portion of theprimary seal162 at a portion of the upperflexible bag portion114 betweenadjacent pleats176. In this location, which is betweenadjacent pleats176, only a single layer of thefilm material190 overlies thelower surface88 of thebag frame90.
• As is best shown inFIG. 25, abag assembly110 according to the preferred embodiment also preferably and advantageously includes a plurality ofsecondary seals170 that are formed in theupper portion114 of theflexible bag112 in an area that is closely adjacent to thebag frame90. Theflexible bag112 is preferably fabricated by welding two sheets of thefilm material190 together. One of the sheets forms the portion of theflexible bag112 that is bonded to thefirst portion120 of thebag frame90, while the other of the sheets forms a portion of theflexible bag112 that is bonded to thesecond portion122 of thebag frame90.
• Each secondary seal includes afirst end172 and asecond end174, and is formed by creating a supplemental heat seal or weld of the two sheets of thefilm material190 together slightly beneath thebag frame190, as is shown inFIG. 25. Thefirst end172 of thesecondary seal170 is preferably separated from thebag frame90 by a small distance D_sthat 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.
• Thefilm material190 preferably is fabricated from a material that substantially prevents transmission of odors therethrough and that is substantially liquid impervious. A preferred embodiment of thefilm material190 is diagrammatically shown inFIG. 31 and includes a firstouter layer192 that defines the outer surface of theflexible bag112, asecond layer194, athird layer196, afourth layer198, afifth layer200, asixth layer202, and a seventh,inner layer204 that defines the inner surface of theflexible bag112.
• Thefilm material190 preferably has a total thickness that is preferably substantially within a range of about 15 μm to about 45 μm, and more preferably substantially within a range of about 20 μm to about 40 μm.
• The first and seventhexternal layers192,204 are fabricated to ensure durability and their ability to be heat sealed together and to thebag frame90. 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 thefilm material190 and the bag-engaging surfaces of thefinger members94 both when thelower portion116 is pushed downwardly by the user through thefinger members94, and when theintermediate portion113 of thebag member112 is engaged and twisted by thefinger members94.
• The first and seventhexternal layers192,204 each both preferably have a thickness that is substantially within a range of about 2.75 μm to about 6.75 μm, and more preferably substantially within a range of about 3.75 μm to about 5.75 μm. The most preferable dimensions are shown in Table 1.
• An anti-block agent is also preferably provided in theexternal layers192,204 in order to prevent the film material from sticking together. In the preferred embodiment a zeolite, preferably CAS NO: 1318-02-1, is used.
• The second and sixlayers194,202 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 theselayers194,202, which is preferably cis-13-Docosenoamide, CAS NO.: 112-84-5.
• The second and sixlayers194,202 each both preferably have a thickness that is substantially within a range of about 3.25 μm to about 7.25 μm, and more preferably substantially within a range of about 4.25 μm to about 6.25 μm. The most preferable dimensions are shown in Table 1.
• Alternatively, the second andsixth layers194,202 could be integrated into the first and seventhouter layers192,204 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 μm to about 12.0 μm, and more preferably substantially within a range of about 9.0 μm to about 11.0 μm.
• The third andfifth layers196,200 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 andfifth layers196,200 each both preferably have a thickness that is substantially within a range of about 1.75 μm to about 5.75 μm, and more preferably substantially within a range of about 2.75 μm to about 4.75 μm. The most preferable dimensions are shown in Table 1.
• The fourth,middle layer198 is a barrier layer that ensures that thefilm material190 is substantially impervious to liquids and odor transmission. It preferably has a thickness that is substantially within a range of about 0.50 μm to about 4.50 μm, and more preferably substantially within a range of about 1.50 μm to about 3.50 μm. The most preferable dimensions are shown in Table 1.
• The respective layers most preferably have a construction and a thickness as described in the following table:

• 	TABLE 1
  	Base Material	Thickness (um/inch/% of total)

  1st	66.0% mLLDPE + 30.0% LDPE + 3.8% slip agent +	4.75 um/0.00019″/15.8%
  layer	0.2% anti-block agent by weight
  (Outer	mLLDPE is preferably ExxonMobil 1018FA
  layer)	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	66.3% mLLDPE + 28.5% LDPE + 3.8% slip agent +	5.25 um/0.00021″/17.5%
  layer	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	Tie layer	3.75 um/0.00015″/12.5%
  layer	Preferably a anhydride-modified linear low-density
  	polyethylene (LLDPE) adhesive resin, most
  	preferably Dupont 41E687
  4th	Barrier layer.	2.5 um/0.0001″/8.4%
  layer	Preferably EVOH, most preferably
  	Nippon Gohsei ET3803
  5th	Tie layer	3.75 um/0.00015″/12.5%
  layer	Preferably a anhydride-modified linear low-density
  	polyethylene (LLDPE) adhesive resin, most
  	preferably Dupont 41E687
  6th	66.3% mLLDPE + 28.5% LDPE + 3.8% slip agent +	5.25 um/0.00021″/17.5%
  layer	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
  7th	66.0% mLLDPE + 30.0% LDPE + 3.8% slip agent +	4.75 um/0.00019″/15.8%
  layer	0.2% anti-block agent by weight
  (Inner	mLLDPE is preferably ExxonMobil 1018FA
  layer)	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

• 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.

Claims (34)

1. A method of storing used diapers for disposal, comprising 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 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.

2. A method of storing used diapers for disposal according toclaim 1, wherein said step of installing the pleated flexible bag includes a step of securing a frame member that is attached to the pleated flexible bag to a portion of the diaper disposal system.

3. A method of storing used diapers for disposal according toclaim 2, wherein the step of securing the frame member to a portion of the diaper disposal system includes securing the frame member to a housing of the diaper disposal system so that the frame member is secured against rotation with respect to the housing.

4. A method of storing used diapers for disposal according toclaim 3, wherein the step of securing the frame member to the housing is performed by positioning a plurality of tab members located on said frame member into corresponding recesses that are defined within the housing.

5. A method of storing used diapers for disposal according toclaim 1, further comprising a step of aligning the second, lower portion of the pleated flexible bag with respect to the storage space of the diaper disposal system prior to said step of removing the pleated flexible bag from the diaper disposal system.

6. A method of storing used diapers for disposal according toclaim 5, wherein said step of aligning the second, lower portion of the pleated flexible bag comprises placing the second, lower portion on a concave, lower surface of the diaper disposal system.

7. A method of storing used diapers for disposal according toclaim 1, wherein said step of installing the pleated, flexible bag includes a step of pushing the second, lower portion of the pleated flexible bag through an opening that is defined by a plurality of resilient finger members.

8. A method of storing used diapers for disposal according toclaim 7, wherein said resilient finger members have a bag engaging portion that is constructed and arranged to have a kinetic frictional coefficient with respect to like material that is substantially within a range of about 0.37 to about 0.67.

9. A method of storing used diapers for disposal according toclaim 7, wherein said plurality of resilient finger members define a central opening in an unstressed position having a minimum diameter that is substantially within a range of about 3 mm to about 13 mm.

10. A method of storing used diapers for disposal according toclaim 1, wherein the frame member is hinged, and wherein said step of removing the pleated flexible bag includes a step of folding the frame member in order to close the pleated flexible bag and to form a carrying handle.

11. A method of opening a diaper pail bag assembly, comprising 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, said 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.

12. A method of using a diaper pail assembly, comprising:

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 0.34 to about 0.64.

13. A method of using a diaper pail assembly according toclaim 12, further comprising a step of twisting an intermediate portion of the flexible bag with the resilient rotatable sealing and gripping member.

14. A method of using a diaper pail assembly according toclaim 12, wherein said bag engaging surface has a kinetic frictional coefficient with respect to an outer surface of the flexible bag that is substantially within a range of about 0.39 to about 0.59.

15. A method of using a diaper pail assembly, comprising:

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.

16. A method of using a diaper pail assembly according toclaim 15, wherein said inner surface has a kinetic frictional coefficient with respect to like material that is substantially within a range of about 0.13 to about 0.33.

17. A method of using a diaper pail assembly according toclaim 15, further comprising a step of lubricating the inner surface with a powder material.

18. A method of using a diaper pail assembly according toclaim 17, wherein the powder material has a mean particle size maximum dimension that is substantially within a range of about 40 microns to about 140 microns

19. A method of using a diaper pail assembly comprising:

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.

20. A method of using a diaper pail assembly according toclaim 19 wherein the minimum lateral dimension of the central opening is substantially within a range of about 85 mm to about 150 mm.

21. A method of using a diaper pail assembly, comprising:

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, said 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.

22. A method of using a diaper pail assembly, comprising:

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, said 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.

23. A method of using a diaper pail assembly, comprising:

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.

24. A method of using a diaper pail assembly according toclaim 23, wherein the lower portion of the flexible bag is substantially sealed.

25. A method of using a diaper pail assembly according toclaim 23, wherein the inner surface has a kinetic frictional coefficient with respect to like material that is substantially within a range of about 0.08 to about 0.38.

26. A method of using a diaper pail assembly according toclaim 25, wherein the inner surface has a kinetic frictional coefficient with respect to like material that is substantially within a range of about 0.13 to about 0.33.

27. A method of using a diaper pail assembly according toclaim 23, wherein the powder material has a mean particle size maximum dimension that is substantially within a range of about 40 microns to about 140 microns.

28. A method of using a diaper pail assembly, comprising:

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;

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.

29. A method of using a diaper pail assembly according toclaim 28, wherein a lower portion of the flexible bag is substantially sealed.

30. A method of using a diaper pail assembly according toclaim 28, wherein the flexible bag is a single use bag.

31. A method of using a diaper pail assembly according toclaim 28, wherein the inner surface has a kinetic frictional coefficient with respect to like material that is substantially within a range of about 0.08 to about 0.38.

32. A method of using a diaper pail assembly according toclaim 31, wherein the inner surface has a kinetic frictional coefficient with respect to like material that is substantially within a range of about 0.13 to about 0.33.

33. A method of using a diaper pail assembly according toclaim 28, wherein the lubricating material comprises a powder material.

34. A method of using a diaper pail assembly according toclaim 33, wherein the powder material has a mean particle size maximum dimension that is substantially within a range of about 40 microns to about 140 microns.

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