WO2009007723A1

WO2009007723A1 - Improved cassette for a waste storage device

Info

Publication number: WO2009007723A1
Application number: PCT/GB2008/002360
Authority: WO
Inventors: Nicholas Curdworth
Original assignee: Sangenic International Ltd
Current assignee: Sangenic International Ltd
Priority date: 2007-07-12
Filing date: 2008-07-10
Publication date: 2009-01-15
Anticipated expiration: 2010-01-12
Also published as: EP2167404A1; DE202007009842U1; EP2167404B1

Abstract

A cassette (100) for use in dispensing1 pleated tubular film for waste storage comprising: an annular body having a generally U-shaped cross-section defined by an inner wall (102), an outer wall (104) and a bottom wall (106), the inner, outer and bottom walls defining a housing (103) for holding pleated tubular film (125), and the inner wall defining a central core (108); and an annular flange (110) extending across the housing, the flange having an inner portion engaging an upper part of the inner wall of the body, and having an outwardly projecting section (113) extending over the housing, the projecting section having an outer edge (112) situated below and inward from an upper edge of the outer wall (104) of the body so as to form a peripheral gap (116) between the projecting section and the outer wall; the cassette being -configured such that, in use, pleated tubular film (125) may be pulled out of the housing, through the peripheral gap.

Description

IMPROVED CASSETTE FOR A WASTE STORAGE DEVICE

This invention relates to a cassette for a waste storage container, for example for storing waste such as used nappies or diapers.

Background to the Invention

WO 2005/042381, the contents of which are incorporated by reference herein, discloses a cassette adapted to locate in a waste storage container. The cassette is particularly adapted for use in waste storage containers for storing waste items such as babies' nappies (or diapers), or other personal waste matter. The cassette comprises an inner wall and an outer wall, and a bottom wall joining the lower parts of the inner and outer walls such that the inner, outer and bottom walls together form a cavity having a U-shaped cross-section. The inner wall defines a central core.

A flange engages with an upper part of the inner wall. The flange extends outwardly, substantially perpendicular to the inner wall. The flange terminates in a circumferential outer edge located inward of an upper edge of the outer wall, so as to form a peripheral gap between the outer wall and the flange.

A profusely circumferentially pleated length of flexible tubular film is located in the cavity of the cassette. The flange partially obscures the tubular film within the cavity. A peripheral gap is provided between the outer edge of the flange and the outer wall, through which the tubular film may be drawn in use.

When the cassette is to be used in conjunction with a waste storage container, a user begins by pulling the top of the tubular film out through the peripheral gap, so that the tubular film extends upwards of the outer edge of the flange. The user then ties the end of the tubular film into a knot, and passes the knotted end down through the central core of the cassette. This knotted end forms the bottom of a waste package into which a used nappy or other waste item can be placed, through the central core of the cassette.

As described in more detail in WO 2005/042381, once a waste item has been placed in the flexible tubular film, the tubular film above the waste item may be twisted, sealing the waste item therein. In such manner, a series of waste items may be separately sealed within the tubular film, and stored in the waste storage container.

Summary of the Invention

The present invention is defined in the attached claims. Thus, a cassette for use in dispensing pleated tubular film for waste storage is provided, the cassette comprising: an annular body having a generally U-shaped cross-section defined by an inner wall, an outer wall and a bottom wall joining a lower part of the inner and outer walls, the inner,, outer and bottom walls defining a housing for holding pleated tubular film, and the inner wall defining a central core; and an annular flange extending across the housing, the flange having an inner portion engaging an upper part of the inner wall of the body, and having an outwardly projecting section extending over the housing, the projecting section having an outer edge situated below and inward from an upper edge of the outer wall of the body so as to form a peripheral gap between the outer edge of the projecting section and the upper edge of the outer wall; the cassette being configured such that, in use, pleated tubular film within the housing may be pulled out of the housing, through the peripheral gap, over the projecting section and the inner portion of the flange, and down through the central core. Preferably the projecting section tapers continuously downwards, from the top of the inner portion, to the outer edge. As a result, flexible tubular film can flow more easily over the surface of the flange. The lower outside edge of the outwardly projecting section, and the continuous downward slope of the projecting section, give less resistance to film flow than existing cassettes in which the flange extends substantially perpendicular to the cassette walls.

Preferably the annular flange further comprises a plurality of strengthening ribs on the underside of the outwardly projecting section. These ribs support the flange and increase its rigidity. Because the projecting section extends downwardly, having an outer edge below the upper edge of the outer wall of the cassette, the strengthening ribs can be deeper and thereby stronger and more supportive. This also enables the ribs to guide the tubular film through the peripheral gap, and away from the corner between the underside of the outwardly extending portion of the flange and the inner wall of the cassette. This helps to ensure that tubular film does not get trapped in this corner, and should lead to fewer rejects during manufacture.

Preferably the top of the annular flange, and/or the outer edge of the projecting section of the flange, are rounded. This assists in smooth flow of tubular film over the flange, into the core of the cassette.

Brief Description of the Drawings

Embodiments of the invention will now be described, by way of example only, and with reference to the drawings in which:

Figure 1 illustrates a perspective view of a waste storage cassette according to an embodiment of the present invention; Figure 2 illustrates a partially cut away perspective view of the cassette of Figure 1;

Figure 3 illustrates a side view of the cassette of Figure 1; Figure 4a illustrates a cross-sectional side view of the cassette of Figure 1, with flexible tubular film housed therein;

Figure 4b illustrates a cross-sectional side view of the cassette of Figure 1 , not showing flexible tubular film therein;

Figure 5 illustrates an enlarged view of portion "A" of Figure 4b; Figure 6 illustrates a plan view of the top of the cassette of Figure 1; and Figure 7 illustrates a plan view of the bottom of the cassette of Figure 1.

Like elements are indicated by like reference numerals throughout.

Detailed Description of Preferred Embodiments The present embodiments represent the best ways known to the applicants of putting the invention into practice. However, they are not the only ways in which this can be achieved.

Figures 1 to 7 illustrate an improved cassette for a waste storage container. The basic operation of the cassette is as described in WO 2005/042381 and need not be discussed in detail herein.

The cassette 100 has an annular body including an inner wall 102, an outer wall 104 and a bottom wall 106 therebetween, forming a U shaped housing 103 for holding a profusely circumferentially pleated length of flexible tubular film 125. The inner wall 102 defines a substantially circular central core 108.

A flange 110 engages with an upper part of the inner wall 102. The flange comprises an inner portion and an outwardly projecting portion 113. The configuration of the inner portion depends on the method of engagement between the flange 110 and the inner wall 102. According to one embodiment, as illustrated, the inner portion comprises a downwardly extending collar 115 having a circumferential rim 117 at its upper end. Preferably the rim 117 has a rounded profile, to assist in smooth flow of the flexible tubular film 125 over the flange 110 and down into the central core 108.

As shown in more detail in Figures 4a, 4b and 5, the downwardly extending collar 115 may comprise a first annular branch 119 and a second annular branch 121, wherein the first 119 and second 121 annular branches are radially spaced from one another, and an upper part of the inner wall 102 of the cassette 100 is configured to insert into the space between the first 119 and second 121 annular branches, to fit the flange 110 to the housing 103. The housing 103 and flange 110 may be joined together by a snap fit or any other suitable locking means.

The outwardly projecting section 113 extends from the top of the inner portion of the flange 110. The outwardly projecting section 113 terminates in a circumferential outer edge 112, located below and radially inward of the outer wall 104. As shown in the figures, the outwardly projecting section 113 preferably tapers continuously downwards from the inner portion, towards the outer wall 104 of the housing 103. Preferably the outer edge 112 has a rounded profile, to assist in smooth flow of the flexible tubular film 125 over the flange 110. A peripheral gap 116 is defined between the outwardly projecting section 113 and the outer wall 104.

In use, a user may draw the flexible tubular film 125 through the peripheral gap 116. When placing a first waste item in the tubular film 125, for storage in a waste storage container, the user begins by pulling the top edge of the tubular film 125 out of the peripheral gap 116, so that it extends upwards of the outer edge 112 of the flange 110. A sufficient length of tubular film 125 should be pulled upwards from the peripheral gap 116 so that the user may gather the top edge of the tubular film 125 together above the central core 108 of the cassette 100, and tie the tubular film into a knot. The user then passes the knotted end of the tubular film 125 down through the central core 108 of the cassette, towards the bottom of the waste storage container.

The knotted end of flexible tubular film 125 may form the bottom of a waste package into which a used nappy or other waste item can be placed. Once a waste item has been placed in the waste package, the tubular film 125 above the waste item may then be twisted or knotted, sealing the waste item therein. The waste package may then be pushed or otherwise directed through the central core 108 of the cassette, into the waste storage container. During this process, the tubular film 125 flows over the flange 110, over the circumferential rim 117 and into the cassette core 108.

Because the flange 110 has an outwardly projecting section 113 which tapers continuously downwards and terminates in a lower outside edge 112, the frictional resistance encountered by the tubular film 125 when flowing over the flange 110 is reduced compared to prior art cassettes in which the flange is perpendicular to the cassette walls.

A series of waste items may be separately sealed within the tubular film and stored in a waste storage container. A waste storage container may contain gripping means for holding the formed waste packages in place, and/or means for cutting the tubular film to release previously formed waste packages.

As shown in Figures 4a, 4b and 5, the underside of the flange 110 preferably includes a plurality of support ribs 123, circumferentially spaced from one another. The support ribs 123 are substantially triangular in cross section, having a first edge along the downwardly extending collar 115 of the inner portion, and a second edge along the underside of the outwardly projecting portion 113. Preferably the third edge extends from a lower part of the inner portion to a part of the outwardly projecting portion 113 near its outer edge 112. In an alternative embodiment, the support ribs can extend from an outer surface of the inner wall 102 of the cassette, to an inner surface of the outwardly projecting section 113 of the flange 110.

Because the outwardly projecting portion 113 of the flange 110 tapers downwards, the support ribs 123 connected to it can have increased depth, and thereby contribute to the rigidity of the flange 110. When the user pulls flexible tubular film out of the cassette housing 103, the support ribs 123 help to guide the tubular film out of the housing 103, through the peripheral gap 112. In addition, the support ribs 123 deflect the tubular film away from the corner between the underside of the flange 110 and the inner wall 102. This helps to prevent tubular film from becoming trapped in this corner, which would disrupt the flow of the tubular film in use, and could cause it to tear. By helping to ensure that tubular film does not get trapped in this corner, this should also lead to fewer rejects during manufacture of the cassette, when the flange 110 is attached to the inner wall 102. The second annular branch 121 also helps to guide the film away from the area of the joint between the flange 110 and the inner wall 102.

Preferably, a series of axially extending guide ribs 118 are circumferentially spaced from one another around the inner surface of the outer wall 104 of the cassette housing 103. In one embodiment, the axially extending guide ribs 118 may be located to align with the support ribs 123 on the flange. The axially extending guide ribs 118 assist in guiding the flexible tubular film out of the housing 103, and in strengthening the outer wall 104. Preferably, an upper part of the axially extending guide ribs 118 has a rounded profile to further assist flow of the tubular film, and to avoid catching or tearing the tubular film.

The cassette can include a second set of axially extending ribs 120 on an outer surface of the inner wall 102, and/or an external flange 122 extending outwardly from the outer surface of the inner wall 102. The cassette can further include a lug or recess for engagement with a cooperating recess or a lug on a waste storage container.

The cassette 100 is preferably formed from a resilient plastics material. The flange 110 and housing 103 can be separately moulded and welded together, or can be locked together as described above. The flexible tubular film may be loaded into the housing 103 by any suitable means. The loading is preferably carried out during manufacture of the cassette, before the flange 110 and housing 103 are attached to one another.

Although discussion has been directed to provision of a cassette for the waste disposal of nappies, it will be appreciated that any appropriate waste such as hygienic waste or household waste can be packaged and disposed of as described above. Similarly the cassette can be used in any appropriate environment - for example domestic, workplace, retail, public, hospital or care environments.

Claims

1. A cassette for use in dispensing pleated tubular film for waste storage, the cassette comprising: an annular body having a generally U-shaped cross-section defined by an inner wall, an outer wall and a bottom wall joining a lower part of the inner and outer walls, the inner, outer and bottom walls defining a housing for holding pleated tubular film, and the inner wall defining a central core; and an annular flange extending across the housing, the flange having an inner portion engaging an upper part of the inner wall of the body, and having an outwardly projecting section extending over the housing, the projecting section having an outer edge situated below and inward from an upper edge of the outer wall of the body so as to form a peripheral gap between the outer edge of the projecting section and the upper edge of the outer wall; the cassette being configured such that, in use, pleated tubular film within the housing may be pulled out of the housing, through the peripheral gap, over the projecting section and the inner portion of the flange, and down through the central core.

2. A cassette as claimed in Claim 1, wherein the projecting section tapers continuously downwards, from the top of the inner portion, to the outer edge.

3. A cassette as claimed in Claim 1 or Claim 2, wherein the annular flange further comprises a plurality of strengthening ribs on the underside of the outwardly projecting section.

4. A cassette as claimed in any of Claims 1, 2 or 3, wherein the top of the annular flange has a rounded profile.

5. A cassette as claimed in any of Claims 1 to 4, wherein the outer edge of the projecting section has a rounded profile.

6. A cassette as claimed in any of Claims 1 to 5, further comprising cooperating inter-engagement means on the upper part of the inner wall of the body and on the inner portion of the flange, for locking the flange to the body.

7. A cassette as claimed in any of Claims 1 to 6, further comprising a plurality of axial ribs on the inner surface of the outer wall.

8. A cassette as claimed in any of Claims 1 to 7, wherein the cassette further comprises inter-engagement means for fitting the cassette to cooperating inter-engagement means on a waste storage container.

9. A cassette as claimed in any of Claims 1 to 8, made of a resilient plastics material.

10. A cassette as claimed in any of Claims 1 to 9, further comprising pleated tubular film within the housing.