Note: Descriptions are shown in the official language in which they were submitted.
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CAT LITTER SIEVING SYSTEM
FIELD OF THE INVENTION
[0001] The disclosure herein relates to systems for sieving solidified waste
from granular cat litter maierial to dispose of the waste and reuse the cat
litter.
BACKGROUND OF THE INVENTION
[0002] The owners of indoor domestic cats typically provide one or more
cat litter boxes in the home. A cat litter box serves as a place for cats to
relieve themselves. The litter box is filled with cat litter. Cat litter is
usually
composed of many individual particles or granules of clay, crushed nut
hulls, paper pulp etc. Commonly cat litter is of the "clumping" type, meaning
that the individual granules clump together in the presence of urine or
feces, absorbing the fluids and odor. The clumps of litter must be removed
and fresh litter added on a regular basis. Alternatively, the entire contents
of the litter box including cat waste and the remaining unused litter must be
dumped and replaced. Dumping the entire contents of the box results in
very rapid use of an owner's supply of cat litter since a large quantity cat
litter which has not come into contact with urine or feces will be dumped out
along with the soiled litter.
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[0003] The simplest way to remove the clumps of waste is to dig each of
the clumps out with a slotted spoon or scoop, transfer them into a trash
bag, and discard them. Often smaller soiled clumps will pass through or fall
off the scoop and remain in the litter box. This means that the litter box is
never completely clean of cat waste after the scooping has been done.
Occasionally the clumps break up while being transferred into the trash
bag, creating a greater mess. Scooping out clumps of waste from the litter
box is an unpleasant daily task for cat owners. Cat owners always need to
keep a supply of small trash bags on hand to receive the soiled clumps.
Some owners also purchase protective gloves to cover their hands so that
they do not have to touch soiled litter while cleaning the litter box.
[0004] The job of cleaning out the litter box is made further unpleasant if
the box only contains a thin layer of cat litter. When cats urinate onto a
thin
layer of cat litter, the urine pools in the bottom of the box before it can be
absorbed into the cat litter. This results in the wet mixtures of litter and
urine sticking to the bottom of the box. When the owner attempts to scoop
out the soiled litter out of the box, it is not possible to get the scoop
under
the soiled litter. The owner then needs to find an alternate tool to scrape
the stuck on soiled litter off the bottom of the box. Subsequent washing of
the litter box is often also required. One possible solution is to place a
deep
layer of litter (3 inches or more) into the box. This increases the amount of
litter purchased and used. It has also been observed that when large
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quantities of cat litter are present, cats will spend more time digging in the
litter and toss quantities of it out of the box, leaving a mess on the floor.
It
would be advantageous to have a system for cleaning a litter box which
requires only a shallow layer of cat litter, and which prevents the problem of
soiled litter sticking to the bottom of the litter box.
[0005] There are many cat litter sieving systems known. However, each
system has drawbacks. For example, one system provides a stack of
plastic sheeting box liners each having sifting holes in it, and one liner
without holes at the bottom of the stack. The entire stack is placed into a
litter box and then filled with litter. After a cat has used the litter, the
top
liner lifted up above the box, allowing loose litter to fall through the holes
and back into the box, while the clumps of soiled litter are retained in the
top liner. The top liner is then transferred to a garage bag or can for
disposal. This system has a number of disadvantages. Granular cat litter
and small clumps may escape the top liner while it is being transferred to a
garbage bag or can, creating a mess in the area. Also, the stack of liners
may become torn when the cat digs in the litter, and become less effective
at its sieving function. Furthermore, it is possible for the stack of
perforated
liners to move out of position when the cat digs in the litter. This may
result
in waste material being deposited between the liners, or under the liners in
the cat box, creating a megs.
[0006] Another system provides a stack of nested litter boxes, the top one
perforated with sieving holes, and the bottom two being solid. Litter is
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placed into the nested boxes. After use by the cat, the perforated top liner
is lifted and shaken gently sifting the granular litter into the bottom litter
box
and retaining clumps of soiled litter in the top box. This system requires
multiple component parts which must be used together. Additionally, the
soiled clumps of litter must still be transferred in the top perforated box
and
poured out into a waste receptacle, with the potential for spills to occur.
[0007] Still other systems provide a litter box which has a built in sieve
component. Typically there are multiple chambers: one containing litter
used by the cat, a repository for clumps of soiled litter, and a sieving
element imposed between the chambers. The box and/or some of its
structural components are moved in order to bring the litter into contact with
the sieving element. Systems of this type often have complex movable
parts which increase the cost of the system and may predispose the system
to malfunction or breakage. These systems require the use of dedicated
litter boxes of special shapes. They cannot be used with existing litter
boxes and parts are not interchangeable with existing boxes.
[0008] It would be desirable to have a system for cleaning a cat litter box
that eliminates the need for manually scooping up and removing clumps of
waste. Preferably the user could use the system without their hands
contacting soiled cat litter.
[0009] Preferably the system would not require a sieve containing soiled
litter to be transported over distances in order to dispose of soiled litter
in a
trash can or bag.
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[00010] The system should be cost effective to manufacture and easy and
convenient to use.
SUMMARY OF THE INVENTION
[00011] A cat litter sieving system comprises a litter handler convertible
between a flat storage configuration, an open container configuration, a
transport configuration, and a disposal configuration, and sieve.
[00012] The litter handler comprises a sheet having a first side and a
second side; a first tab extending from said first side, a second tab
extending from said second side; a first end and a third tab extending from
said first end. The litter handler further comprises a shaping element to
form the sheet into the open container configuration.
[00013] The shaping element is a curvature heat formed in the sheet to
divide the sheet into a substantially planar polygonal base, and a plurality
of
interconnected wall panels extending upwardly from the substantially planar
polygonal base to form the open container configuration.
[00014] In an alternative embodiment, the shaping element is a plurality of
fold lines in the sheet defining substantially planar polygonal base and a
plurality of interconnected wall panels; and wherein said plurality of
interconnected wall panels may be folded upward from said plurality of fold
lines to form an open container.
[00015] The plurality of fold lines comprise a center fold line extending
inwardly from a corner of the sheet and substantially bisecting said corner;
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a first lateral fold line and a second lateral fold line; said first lateral
fold line
and said second lateral fold line positioned one on either side of the center
fold line and extending inwardly to converge with the center fold line.
[00016] The sieve comprises a riser to retain a frame at a selected distance
above a litter box, said frame supporting a mesh member having a
perimeter and defining a plurality of holes therethrough of sufficient size to
permit granules of cat litter to pass through while retaining clumps of cat
litter.
[00017] A method of removing clumps of cat litter contaminated with waste
material from a granular cat litter comprises the following steps. A litter
handler comprising a sheet having a first side and a second side; a first tab
extending from said first side, a second tab extending from said second
side; a first end and a third tab extending from said first end is placed into
a
car litter box with the first tab, the second tab and the third tab extending
outside the litter box. Granular cat litter is placed inside the litter
handler.
After some of the granular cat litter has been soiled causing clumps of cat
litter contaminated with waste material, a user brings the first tab into
contact with the second tab forming the transport configuration of the litter
handler containing the cat litter and cat litter clumps. The litter handler is
lifted out of the litter box. The next is placing into the litter box a sieve
comprising a riser to retain a frame at a selected distance above a litter
box,
said frame supporting a mesh member having a perimeter and defining a
plurality of holes therethrough of sufficient size to permit granules of cat
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litter to pass through while retaining clumps of cat litter. The cat litter is
poured from the litter handler into the sieve. After all of the granular cat
litter
has passed through the sieve leaving clumps of cat litter in the sieve, the
sieve is removed from the litter box. The clumps of cat litter are returned to
the litter handler for disposal.
BRIEF DESCRIPTION OF THE DRAWINGS
[00018] FIG. 1A is a plan view of a litter handler according to the present
invention shown in a flat storage configuration.
[00019] FIG. 1B is a perspective view of the litter handler of FIG. 1A shown
in an open container configuration.
[00020] FIG. 2 is a perspective view of an alternative embodiment of the
litter handler deployed in a cat litter box.
[00021] FIG. 3 is a perspective view of the litter handler of FIG. 2
containing
granular cat litter.
[00022] FIG. 4 is a perspective view of the litter handler of FIG. 2
containing
granular cat litter and clumps of litter contaminated with waste matter.
[00023] FIG. 5 is a perspective view of the litter handler of FIG. 2 being
converted into the transport configuration and lifted out of the litter box.
[00024] FIG. 6 is a perspective view of a sieve being placed into the litter
box.
[00025] FIG. 7 is a perspective view of the sieve in the litter box.
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[00026] FIG. 8 is a perspective view of the litter handler transporting the
granular cat litter and clumps of litter contaminated with waste matter into
the sieve.
[00027] FIG. 9 is a perspective view of the clumps of litter contaminated
with waste matter retained in the sieve and the granular cat litter inside the
litter box.
[00028] FIG. 9A is a perspective view of litter box containing granular cat
litter after the sieve containing the clumps of litter contaminated with waste
has been removed.
[00029] FIG. 10 is a perspective view of the contents of the sieve being
emptied into the litter hander.
[00030] FIG. 11 is a perspective view of the litter handler in a disposal
configuration.
[00031] FIG. 12A is a perspective view of a sieve according to an
alternative embodiment of the present invention.
[00032] FIG. 12B is an exploded view of the sieve of FIG. 12A.
[00033] FIG. 13A is an exploded perspective view of a sieve according to
an alternative embodiment of the present invention.
[00034] FIG. 13B is a perspective view of the sieve of FIG. 13A shown in a
collapsed configuration.
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DETAILED DESCRIPTION OF EMBODIMENTS
[00035] The present invention provides a cat litter sieving system shown in
the accompanying FIG. generally by reference numeral 10. The cat litter
sieving system comprises a litter handler 12 and a sieve 13. As shown in
FIG. 1A, the litter handler 12 comprises a sheet 14. The sheet 14 has a
first side 16 and a second side 18; and a first end 20. A first tab 24 extends
from the first side 16. A second tab 26 extends from the second side 18,
and a third tab 28 extends from the first end 20 of the sheet 14. Optionally,
the sheet 14 has a second end 22. A pair of dust retainers 29, 29 extends
from the second end 22 of the sheet 14.
[00036] The sheet 14 can be fabricated from a flexible sheeting material.
The sheet is preferably, though not necessarily water resistant. The sheet
may be constructed from a variety of flexible sheeting materials, including
waterproof paper, wax paper, polyethylene terephthalate (PET), cellulose
acetate, polyvinyl chloride (PVC), polythene, nylon, acrylic, textile, and
fabric. The sheet 14 is
preferably constructed from high density
polyethylene, having a sheet thickness in the range of 50.8 pm to
101.60 pm. The material is high density polyethylene having of 76.2 pm.
A person skilled in the art will recognize that other suitable materials may
be used without departing from the present invention.
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[00037] The sheet may also be treated to provide fragrances and/or odor
eliminating additives. In a further
modification, the sheet may be
constructed from moisture sensitive materials so that when the contained
litter becomes moist from use, the sheeting material changes colour to
provide a visual indication. This will alert the owner that the litter has
become soiled and requires removal.
[00038] The litter handler 12 is convertible between a flattened storage
configuration 12A shown in FIG. 1A, an open container configuration 12B
as shown in FIG. 1B, a transport configuration 12C as shown in FIG. 5 and
FIG.8, and a disposal configuration 12D as shown in FIG. 11.
[00039] A shaping element 30 serves to form the sheet 14 into the open
container configuration. Several embodiments of the shaping element are
possible.
[00040] In a first embodiment, shown in FIG. 2 through FIG. 11, the shaping
element 30 is a curvature 32 formed in the sheet 14 to divide the sheet into
a substantially a planar polygonal base 34, and a plurality of interconnected
wall panels 36 extending upwardly from the substantially planar polygonal
34 to form the open container configuration. It is preferred that the base 34
will be generally rectangular, though having curved corners. The generally
rectangular shape matches the generally rectangular shape of conventional
cat litter boxes. It should be understood that the particular shape of the
base 34 is not determinative of the present invention, but rather sheets may
be manufactured in variety of base shapes for use with a variety of litter box
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shapes. In the first embodiment, the curvature 32 is created through plastic
forming techniques. It will be understood by a person skilled in the art that
a formed curvature is an appropriate shaping element 30 in instances
where the sheet 14 is constructed from a material which can be formed.
[00041] In an alternative embodiment shown in FIG. 1A and FIG. 1B, the
shaping element 30 is a plurality of fold lines in the sheet defining
substantially planar polygonal base and a plurality of interconnected wall
panels. The fold lines are located at each of the corners of the sheet. A
centre fold line 38 substantially bisects each corner of the sheet 14. At each
corner, a first lateral fold line 40 and a second lateral fold line 42 are
spaced
equidistant from the first fold line 38. The first 40 and second 42 lateral
fold
lines extend inwardly from the edges of perimeter of the sheet and
substantially converge to meet the centre fold line 38. When the corners
of the sheet are folded about each centre fold line 38 such that the
respective first lateral fold line 40 and second lateral fold line 42 are
closely
adjacent with each other, the handler 20 is shaped into its open container
configuration. The handler 12 can then be placed into a litter box for use.
[00042] The sheet 14 can be heat crimped along the meeting of each
respective first lateral fold line 40 and second lateral fold line 42 in order
to
form a heat sealed gusset corner 44. FIG. 1B shows a handler having heat
sealed gusset corners. If the formation of gusset corners 44 improves the
strength and stability of the handler 12, allowing it to retain its open
container configuration even when it is not supported by the walls of a cat
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litter box. The handler 12 can still be folded into a flat storage
configuration
12A since it is constructed from a flexible material.
[00043] In an alternative embodiment, the shaping element is a plurality of
score lines. The positioning and direction of the score lines would be the
same as discussed in above with regard to fold lines. The choice between
score lines and fold lines is a function of the material selected for
manufacture of the sheet 14. If the material is such that it can be readily
folded, such as paper then fold lines will be used. If the material selected
does not readily remain folded, a pattern of score lines may be scored into
the sheet during the manufacturing process as a shaping element to form
the sheet into the open container configuration. Since the positioning
remains the same whether fold lines or score lines are used, FIG. 1A
illustrates the positioning of either fold lines or score lines, and the
reference numerals 38, 40, 42, 44 are equally applicable to reference the
respective score lines or fold lines.
[00044] The litter handler is deployed in a litter box 48 with the first tab
24,
the second tab 26, the third tab 28, and the pair of dust retainers 29, 29
each extending over a respective side and/or end of the litter box. The
base 34 of the litter handler 12 rests on the bottom of the litter box 48, and
the sides 36 are held in position along the sides of the litter box by the
tabs
26, 28, and the dust retainers 29, 29 extending over the sides of the litter
box. Clean granular cat litter 60 can then be placed into the litter box 48
for
use by a cat.
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[00045] When it is time to remove clumps 62 of soiled litter from the litter
box, the titter handler is converted into the transport configuration. The
first
tab 24 is located on the first side of the sheet 16 and is centred with
respect
to first side 16. The second tab 26 is located on the second side 18 in a
centred position. Thus, the first tab 24 and the second tab 26 are
positioned opposite one another. The user brings the first tab 24 into
contact with the second tab 26 and holds them securely together forming
the transport configuration 120. The positioning of first tab 24 and second
tab 26 opposite one another and each at the centre of its respective side
16, 18 of the sheet 14 serve to balance the cat litter 60,62 within the litter
handler 12. Tabs 24 and 26 serve as lifting handles to lift the litter handler
12 and its contents. It should be noted that the sheet 14 which forms the
litter handler 12 is not perforated, and has no sieving holes. The base 34
supports both the granular cat litter 60 and the clumps 62 of litter
contaminated with waste material. The interconnected wall panels 36 are
contiguous with the base 34 and serve to prevent litter 60, 62 from spilling
out of the litter handler 12. The litter handler 12 is then used to lift the
cat
litter 60, 62 from the litter box 48 in order to be sieved. The third tab 28
can
be grasped by the user in order to further stabilize the litter handler 12.
The
tab 28 further serves as a handle to guide and direct the flow of cat litter
60,
62 as it is being poured into the sieve 13. The dust retainers 29, 29
positioned on the second end 22 of the sheet 14 are each allowed to hang
down. When the litter is being poured from the handler 12, the pair of tabs
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is located one on either side of the stream of cat litter 60, 62 while it
pours
from the litter handler 12. The dust retainers 29, 29 act to direct dust and
fine particles toward the centre of the flow of cat litter 60, 62. This action
lessens the amount of litter dust which would otherwise rise whenever cat
litter is poured from one vessel into another.
[00046] In a simplified embodiment of the litter handler 12, the sheet 14
remains flat and planar until it is deployed in a litter box 48 with the first
tab
24, the second tab 26, the third tab 28, and the pair of dust retainers 29, 29
each extending over a respective side and/or end of the litter box. Once
deployed, the sheet takes on an open container shape as it lies in the box
suspended by the tabs 24, 26, 28, and dust retainers 29, 29. In this
embodiment, the sheet is shaped into the open container configuration by
the interplay of the suspension of the sheet 14 by the tabs 24, 26 and 28
and the sides 16, 18 and ends 20, 22 resting against the sides and ends of
the litter box 48. This simplified embodiment is less preferred than the other
embodiments, since the sheet 14 may become dislodged from its resting
place if the tabs may slip out of their extended positions over the sides of
the litter box 48. Additionally, when the litter handler 12 is removed from
the litter box and laid down on a flat surface, it will revert to its flat
configuration. This means that the litter handler 12 according to the
simplified embodiment cannot be laid down on a flat surface while it is full
of
cat litter. It will be laid flat when it is to be used for disposal of litter
clumps
contaminated with waste material. The litter clumps will be poured onto the
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litter handler 12 from the sieve (discussed below), and there is the potential
for litter clumps to roll off of the litter handler before it is folded or
rolled
around the litter clumps to form the disposal configuration.
[00047] Typically the clumps 62 of cat litter contaminated by waste material
are significantly larger than granular cat litter 60, and can be readily
separated by sieving. The sieving system 10 of the present invention
further comprises a sieve 13. The sieve 13 comprises a riser 50 to retain a
frame 52 at a selected distance above a litter box 48. The riser could be an
extension of the frame. Alternatively, the riser 50 could be comprised of
multiple legs 68. The frame 52 supports a mesh member 54.
[00048] The mesh member 54 has a perimeter 56 and defines a plurality of
holes 58 therethrough. The mesh member 54 may be woven, extruded,
expanded, knitted, or electroformed. It may likewise be constructed from a
variety of suitable materials including plastics, metals, and other durable
materials. The mesh member 54 is preferably molded from a plastic
material. The holes 58 of the mesh member must be of a sufficient size to
permit cat litter granules 60 to pass through easily, while retaining clumps
62 of cat litter contaminated with waste material. The selection of a material
from which to construct the mesh member 54, and the particular size and
shape of the holes 56 is within the ability of a person ordinarily skilled in
the
art. By way of example only, it has been determined that a mesh having
holes 58 approximately 8 mm by 8 mm in size and separated from one
another at a distance of approximately 2 mm is suitable to retain clumps
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while allowing granules of litter to pass through. The particular shape of the
holes is not determinative, so long as the passage of litter granules is not
impeded.
[00049] The frame 52 of the sieve 13 extends above the mesh member 54
at all points along the perimeter 56 thereof to form a box structure with the
mesh member 54 being the bottom of the box structure. This box structure
retains the granules 60 of cat litter and any clumps 62 in contact with the
mesh member 54 so that the cat litter granules 60 may be separated from
the clumps 62.
[00050] There are multiple embodiments of the sieve 13 according to the
present invention. In the simplest embodiment, the sieve 13 can be
constructed as a single body molded from plastic. The riser 50 may simply
be a downward extension of the frame 52 to retain the frame 52 at a
selected distance above a litter box 48 when in use. A suitable distance
would be approximately 8 cm but could be varied without departing from the
present invention. Alternatively, the riser 50 may comprise a plurality of
legs.
[00051] The sieve 13 is reusable and can be stored between uses. The
same sieve 13 can be wkh any new or existing litter box. In alternative
embodiments, the sieve can be constructed in parts and can be
disassembled for more compact storage.
[00052] In one embodiment, the riser 50 comprises a plurality of legs that
are removably supportingly attached to the frame 52. Fastening elements
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(not shown) can be provided on the legs and frame for a friction fit, or other
conventional fastening.
[00053] Alternatively, as shown in FIG. 12 A and 12B, the frame 52
comprises a plurality of side panels 66. Each of the side panels 66 defines
a riser 50 and a support 68 for the mesh member 56. Each of said side
panels 66 having a first end 70 having a means 72 for retainingly mating
another one of said plurality of side panels 66. Each of said side panels 66
also has a second end 74 having a second means 76 for retainingly mating
with another one of said plurality of side panels. As illustrated in FIG. 12A
and B, the first mating means 72 and the second mating means 74 may be
tongue and groove components. Other conventional mating means may be
used. It does not matter whether two of the panels 66 have the same first
mating means 72 and second mating means 74 (i.e. both tongues) or two
different complementary mating means (one tongue and one groove) so
long as the panels may be retaining mated to form the frame 52. Each of
the panels has a support 68 for the mesh member 56. The support 68 may
be a ledge extending from the panel 66, such that when all of the panels 66
are connected, the ledges are aligned and the mesh member can rest
securely on the ledges, suspended above a litter box 48 at a distance
determined by the height of the riser 50. Alternatively, the support 68 may
be contoured as a channel 78 to slidingly receive and support the mesh
member.
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[00054] In an alternative embodiment of the present invention shown in
FIG. 13A and 13B, the frame 52 comprises a plurality of side panels 66;
each side panel defining a riser 50 and a support 68 for the mesh member
56. The panels 66 each have hinging means 80 for retaining another one of
said plurality of side panels 66. One of the panels and the mesh member
may also be provided with means for hingedly engaging. This will allow the
mesh means to be rotated out of the way and the frame to be folded for
storage.
[00055] The litter sieving system according to the present invention is used
to remove clumps of soiled cat litter from a granular cat litter according to
the following basic method. The litter handler 12 comprising a sheet 14
having a first side 16 and a second side 18; a first end 20 and a second end
22; a first tab 24 extending from said first side16, a second tab 26 extending
from said second side 18, and a third tab 28 extending from said first end
20 is placed into a cat litter box 48 with the first tab 24, the second tab 26
and the third tab 28 extending outside the litter box 48. The user then
places granular cat litter 68 inside the litter handler 12. The cat uses the
litter in the ordinary manner. Eventually, it will be time to remove the
soiled
cat litter clumps from the litter box. After some of the cat litter 60 has
been
soiled causing clumps 62 of cat litter contaminated with waste material, the
user brings together the first tab, the second tab and the third tab to
contain
the cat litter within the litter handler. The bringing together of the tabs
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converts the litter handler into the transport configuration. The user lifts
the
litter handler 12 containing the cat litter out of the litter box 48.
[00056] A second new, clean litter handler is placed into the litter box 48.
[00057] A sieve 13 comprising a riser to retain a frame at a selected
distance above a litter box, said frame supporting a mesh member having a
perimeter and defining a plurality of holes therethrough of sufficient size to
permit granules of cat litter to pass through while retaining clumps of cat
litter is placed into the litter box on top of the second new litter handler
12.
The cat litter is then poured from the litter handler 12 into the sieve 13.
Gently rocking the sieve from side to side will assist in bringing the
granular
litter into contact with the holes 58 in the mesh member, allowing them to
pass through the mesh member. After all of the granular cat litter 60 has
passed through the sieve 13 leaving clumps 62 of cat litter in the sieve 13,
the sieve 13 is removed from the litter box and the clumps 62 of cat litter
are
poured back into the litter handler 12 and it is rolled up into the disposal
configuration and thrown into the trash, thereby disposing of the cat litter.
[00058] Multiple litter handlers 12 may be layered inside the litter box 48 so
that a supply of litter handlers is constantly available for repeated
cleanings
of the litter box over time.
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