Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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PET LITTER TRAY, BOX, AND SYSTEM
FIELD
[0001] This disclosure relates to pet waste devices.
BACKGROUND
[0002] U.S. Patent No. 5,325,815 incorporated herein by reference
discloses a
sifting device for pets to deposit their waste, and for a user to separate the
waste from
the pet litter for disposal. The device has three nestable sifting trays. Each
tray has
handles, sidewalls, and a base. The thickness of the tray steadily increases
when going
from the handles to the base. Each tray base defines openings therethrough.
When
stacked, the bottom surface of each upper-tray is in direct continuous contact
with the
top surface of the tray therebeneath. When two trays are stacked in the proper
configuration, the openings do not overlap. This inhibits the litter from
passing through
the openings in the upper tray. To sift, a user lifts the top-most tray from
the two bottom
trays to expose the top-most tray grating. The top-most tray is shaken causing
litter to
fall through the grating while the pet waste stays in the top-most tray. Once
the waste is
disposed, the top-most tray is made the bottom tray of the two other nested
trays.
Failure to properly orient the top-most tray as the bottom tray, however, may
lead to
litter inadvertently spilling from the device via the grating.
SUMMARY OF THE INVENTION
[0003] A pet litter tray, box and system. The litter box comprises
multiple trays.
The trays are nestable within one another. Each tray comprises a base defining
one or
more openings. The opening allows litter to pass therethrough. When stacked in
a first
orientation, the openings of each upper tray are blocked by portions of the
the base of
the adjacent lower tray thus retaining the litter. The top-most tray is lifted
to sift the
unused litter into the two nested lower trays. The top-most tray is added to
the bottom of
the two nested trays in a selected orientation. The trays may comprise flanges
extending from the openings to contact the base of the lower tray when stacked
to
retain litter. The flanges help keep the tray base thin but maintain rigidity
and strength.
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The flanges may also help separate the trays from one-another when nested. The
flanges may have bridges therebetween. The trays may comprise protrusions
extending
from the rim to contact an adjacent lower tray to indicate improper
orientation of the
trays.
[0004] In an embodiment, the tray may comprise a base defining an opening
to
allow material to pass through; a flange extending from the opening, the
flange
configured to contact the base of a second tray in a selected orientation to
retain a
material in the tray; and a sidewall extending from the base to retain the
siftable material.
[0005] The second tray may be the same as the tray.
[0006] The tray may comprise a rim extending from the sidewall, and a
protrusion
extending from the rim to contact the second tray when the tray is nested in a
second
selected orientation within the second tray.
[0007] The tray may comprise a second flange and a bridge extending from
the
flange to the second flange.
[0008] In an embodiment, the litter box may comprise a plurality of
trays, each
tray configured to be nested in a first orientation within any of the other
trays, each tray
comprising a base defining an opening to allow a material to pass through; a
flange
extending from the opening for contacting the base of a lower tray to retain
the material;
and a sidewall extending from the base to retain the material.
[0009] The flange may extend around the periphery of the opening. The
thickness of the base and the sidewall may be the same. There may be three or
more
trays.
[00010] Each of the trays may comprise a rim extending from the sidewall,
and a
protrusion extending from the rim to contact a lower tray when the tray is
nested in a
second orientation within the lower tray.
[00011] Another embodiment of the litter box may comprise a plurality of
trays,
each tray configured to be nested within any of the other trays, each tray
comprising a
base defining an opening to allow a material to pass through; a sidewall
extending from
the base to retain the material; a rim extending from the sidewall, and a
protrusion
extending from the rim, wherein the protrusion of an upper tray contacts the
rim of an
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immediately lower tray when the upper tray is nested in a second orientation
within the
lower tray.
[00012] The number of trays may be three or more. The trays may be
identical to
one another.
[00013] The rim may define an opening, the opening for permitting a
protrusion of
a rim of an upper tray to pass therethrough when the trays are in the first
orientation.
The opening may be a smaller width rim. The opening may be an aperture. The
opening
may be a notch The protrusion may form a pivot point at its end.
[00014] Each of the trays may further comprise a flange extending from
around the
opening to a position such that when any upper tray of the trays is nested in
a first
orientation within an immediately lower tray, the flange of the upper tray
contacts the
base of the lower tray to retain a material.
BRIEF DESCRIPTION OF THE DRAWINGS
[00015] Fig. 1 shows a perspective view of an embodiment of a sifting tray
according to the present disclosure.
[00016] Fig. 2 shows a side view of the sifting tray of Fig. 1.
[00017] Fig. 3 shows a cross-section side view of the sifting tray of Fig.
1 taken
from cut lines A-A.
[00018] Fig. 4 shows a bottom view of the sifting tray of Fig. 1.
[00019] Fig. 5 shows a perspective view of an embodiment of a sifting
system
according to the present disclosure comprising the trays of Fig. 1.
[00020] Fig. 6 shows a front view of the sifting system of Fig. 5.
[00021] Fig. 7 shows a front view of the sifting system of Fig. 5 with two
trays
incorrectly oriented.
[00022] Fig. 8 shows a cross-sectional view of the sifting system of Fig.
5 taken
from cut lines B-B.
[00023] Fig. 9 shows a perspective view of an embodiment of a sifting tray
according to the present disclosure.
[00024] Fig. 10 shows a perspective view of an embodiment of a sifting
tray
according to the present disclosure.
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,
[00025] Fig. 11 shows a front view of an embodiment of a sifting system
according
to the present disclosure comprising three nested sifting trays of Fig. 9.
[00026] Figs. 12 and 13 shows perspective expanded views of embodiments
of
flanges in accordance with the present disclosure.
DETAILED DESCRIPTION
[00027] Figs. 1-4 show different views of an embodiment of a sifting tray
10
according to the present disclosure. The sifting tray 10 has a rectangular-
like cross-
section, and comprises a base 12 and four sidewalls 14 that comprise a first
pair of
opposing side walls 14a and a second pair of opposing side walls 14b. The
sidewalls 14
are connected to the base 12 to enclose a space for containing a granular
material,
such as pet litter. The base 12 has an upper surface 34 and a lower surface
36. The
tray may be of any shape such as circular and square.
[00028] The base 12 defines a plurality of slots or openings 22 (also
referred to as
grates) extending from the upper surface 34 through to the lower surface 36.
The slots
22 are for allowing pet litter to pass through the base. The figures show the
grates
extending vertically across the base 12. The plurality of slots 22 may be
arranged in any
other pre-set pattern to allow the sifting tray to be used with one or more
substantially
identical trays to form a sifting system of the present invention as discussed
below.
Having a system which uses identical trays can help reduce manufacturing
costs.
Manufacturing different trays can, for example, significantly increase the
tooling costs
since a unique mold would be required for each different tray.
[00029] Any slots arrangements may be used so long as, when the nestable
trays
are stacked correctly, the slots of a top tray are blocked by the upper
surface of one or
more lower trays. The slots 22 may be sized and shaped to ensure that a
siftable
material such as the solid waste or the clumped litter is able to be trapped
and
separated from the remaining unused litter when sifting. In this embodiment,
the slots
22 are each elongated and narrow ones. The slots may also be round, square or
the
like in shape.
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[00030] The interior space defined by the base 12 and the sidewalls 14 is
shaped
to allow another substantially identical sifting tray to be nested inside. To
that end, the
sidewalls 14 extend upwardly and outwardly from the base 12 at certain angles
such
that the lower surface of the base 12 of one upper tray is able to reach down
to contact
the upper surface of the base 12 of another lower adjacent tray in the stack
of the trays.
[00031] Referring to FIG. 2, each of the slots 22 of the sifting tray 10
may
comprise a flange 24 around the periphery of the slot 22. The flange 24
extends
downwardly from the lower surface 36 of the base 12. The flanges 24 are lips
or collars
that protrude downward from the base 12. The flange 24 may have a height that
is two
or more times thicker than the base 12. The flanges 24 may each have a smooth
bottom surface that has a contour corresponding to that of the upper surface
34 of the
base 12. When two trays 10 are stacked one on top of the other in the correct
orientation, the bottom of the flanges 24 of the upper sifting tray may
contact the upper
surface of the lower sifting tray. This contact inhibits the litter from fully
passing through
the upper tray into the lower tray, and out of the slots of the lower tray. In
effect, the
flanges 24 create pockets of litter within the slots 22. The flanges 24 can
help reduce
the overall thickness of the base of the tray 10 but still create contact
between the trays
to inhibit litter from completely passing from out of the top tray into the
bottom tray.
Reducing the thickness of the tray base 12 helps reduce the total amount of
material
used which, in turn, can help reduce material costs, manufacturing costs, and
shipping
costs (from weight savings). Reducing tray weight may also be helpful since a
user
needs to lift the tray to sift the litter from the waste. Flanges 24 can also
help stiffen or
strengthen the base notwithstanding reducing the amount of material used in
the base
12. The flanges 24 may allow the thickness of the base of the tray to be
similar to the
thickness of the walls of the tray and other parts of the tray.
[00032] In an embodiment, the tray 10 comprises a rim 16 extending
outwardly
from the sidewalls 14 at the top. The rim 16 may have a substantially planar
top face
and a bottom face. In one embodiment, the rim 16 comprises a first portion 18
with a
first width H1 and a second portion 20 with a second width H2, in which the
first width
H1 is greater than the second width H2. Due to the width difference, a
recessed area 30
may be formed as shown by the area enclosed by the stippled lines. The rim 16
may
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extend continuously or partially around the periphery of the sidewalls 14 of
the sifting
tray 10. In the embodiment shown in Figs. 1-4, the rim 16 extends continuously
around
the periphery of the entire sidewalls 14 of the sifting tray 10. The rim 16
may serve as a
handle for a user to grab the tray 10. The rim 16 may also be used to stiffen
and/or
reinforce the tray 10. Litter can be heavy, so each tray 10 is each
individually sufficiently
strong to withstand holding litter at a height and to withstand a sifting
motion. Stiffening
the tray can help prevent the tray 10 from buckling, twisting, deforming past
the point of
failure, or breaking.
[00033] The sifting tray 10 may comprise protrusions 26 which are attached
to the
first portion 18 of each end of the rim 16. The protrusion 26 may project
downwardly
from the rim 16 toward the base. The protrusions 26 may extend vertically from
the
bottom face of the rim 16. The protrusions 26 may have a pointed end. The
pointed end
may have a smooth or rounded contact surface to avoid scratching a user's
hands. The
protrusion 26 may be a flat tab. The flat tab may have a reinforcing rib
attached to the
back to increase the strength and stiffness of the protrusions 26.
[00034] A litter box comprising a sifting system may be formed by
combining the
sifting trays together so that an upper tray is nested in an adjacent lower
tray
without interference with each other. The sifting system is a container to
hold a siftable
material such as pet litter without leakage. When containing pet litter, it
functions as a
conventional pet litter box for a pet to climb into the top tray of the
sifting system for
excretion of pet waste such as urine and feces. The sifting system also serves
as a
sieve for separating the litter from the waste by lifting the top tray off its
lower trays of
the sifting system. Sifting helps separate the pet's solid excrement deposited
in the litter
and clumped litter from the remaining unused litter. The material which passes
through
the openings 22 falls into the bottom two trays. This helps conserve unused
litter thus
saving user's time and money.
[00035] A siftable material may be any granular or particulate material
that
comprises particles of different sizes in which unwanted larger particles need
to be
removed. For example, the siftable material may be pet litter, such as cat
litter. In one
preferred application, the sifting tray 10 is used to sift pet litter to
remove and dispose
solid waste and/or liquid waste clumped litter from the unused portion of the
litter. The
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following will take pet litter as an example to describe how the present
invention works
with pet litter. However, it should be appreciated that the exemplary pet
litter does not
serve as a limitation to the siftable material.
[00036] Fig. 5 shows a sifting system 100 according to the present
disclosure. The
sifting system 100 comprises three substantially identical sifting trays 10
illustrated in
Figs. 1-4, in which the three sifting trays 10 are stacked one on top of
another and each
upper tray is nested stably in its adjacent lower tray without interference
from each other.
For ease of discussion, the three sifting trays 10 are denoted as upper tray
10a, middle
tray 10b, and bottom tray 10c from top to bottom, respectively. Of any two
stacked
adjacent trays of the sifting system, one tray on top of the other may be
referred to as
an upper tray, and the adjacent lower one may be referred to as a lower tray.
[00037] To form the sifting system 100 according to the present invention,
the
multiple sifting trays 10 are stacked in the correct orientation, one on top
of another,
without interference therebetween. In this context, when these trays are being
stacked,
each tray needs to be placed by turning in a generally horizontal plane a pre-
determined
degree relative to the adjacent tray. The degree of rotation may be 180. Figs.
5-6 show
perspective, side and front views of a sifting system 100 in one embodiment,
in which
the three trays 10a, 10b, 10c are nested in one another with the correct
orientation.
Each tray is stacked to each other by being turned 180 degree relative to
another
adjacent one. Being stacked in this manner, the openings of the slots 22 of
the top tray
10a are blocked by the upper base surface 34 of the middle tray 10b, and the
slots of
the middle tray 10b are also blocked by the lower tray 10c, whereby a material
to be
sifted is contained within the upper tray 10a and prevented from passing all
the way
through the slots 22 of the top tray 10a. As such, when the sifting system 100
of the
stacked trays is placed on a flat surface, each of the trays 10a, 10b, 10c
will sit stably
and the upper base surface 34 of the top tray 10a is substantially flat.
[00038] Fig. 6 shows a front view of the system 100 of Fig. 5. When the
three
trays 10a, 10b, 10c are correctly nested in one another in a way described
above, the
protrusions 26 of the three trays are staggered at either side of the trays
such that the
protrusions 26 of any tray will not be obstructed by, or otherwise interfere
with, any parts
of any other trays such as the lip or rim of the other tray. This interference
is
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pronounced by the protrusion 26 helping ensure the user is made aware of the
incorrect
orientation of the trays. As discussed earlier, due to the width difference
between the
first portion 18 and the second portion 20 of the rim 16, a recessed area 30
is formed
along the second portion 20. When stacking the trays 10a, 10b, 10c, this
recessed area
30 enables the protrusions 26 of the top tray 10a and the middle tray 10b to
pass
through the recessed area of their respective lower trays without obstruction
or
interference from any other trays. For this purpose, the vertical height of
the protrusions
26 of the sifting tray 10a may be less than or equal to the distance from the
lower
surface of the first portion 18 of the top tray 10a to the face 2 of the
bottom tray 10c. In
other words, while stacking at least three trays one on top of another, the
protrusions 26
of any tray will not interfere with any other trays, which ensures that the
slots of any
upper tray of the stacking are able to reach down to contact the upper base
surface of
its adjacent lower tray. Furthermore, to avoid this interference, the
protrusions 26 of the
sifting tray 10 can be disposed at a position on the lower face of the first
portion 18 of
the rim 16 such that the protrusions 26 of the top tray 10a and the middle
tray 10b can
be received within the recessed area 30. Referring to the tray 10 of Fig. 1,
for example,
the distance H3 should be more than the distance H4.
[00039] Fig. 7 shows a front view of the system 100 of Fig. 5 wherein the
middle
tray 10b and the bottom tray 10c are not correctly oriented with respect to
each other.
Because the orientation is not correct, the protrusion of the middle tray 10b
contacts the
rim of the bottom tray 10c. This causes the middle tray 10b to rock within the
bottom
tray 10c giving indicating to the user that the trays are not correctly
oriented.
[00040] Fig. 8 shows a cross-sectional side view of the sifting system 100
of Fig. 5
taken from the line B-B of Fig. 5. Tray 10a is nested in tray 10b, and tray
10b is nested
in tray 10c. The flanges 24a, 24b, 24c of each upper tray contact the upper
surface 34
of the base 12 of the lower tray such that the opening of the flanges 24a,
24b, 24c are
completely occluded. The flanges 24a, 24b of the trays 10a, 10b separate or
space
apparat the trays 10a, 10b and their rims 16a, 16b, 16c. The spacing between
the rims
can facilitate the user to fit their fingers in to grab the top tray, i.e.
tray 10a, with hands
from below the rim 16a to lift it up. Furthermore, the flanges 24 can help
optimize the
nesting of the trays. Without these flanges to properly nest the sifting trays
in one
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another, the base and sidewalls of each tray would need to have a particular
configuration to perfectly fit another so as to inhibit the litter from
passing through small
spaces between the two trays. It may be difficult to achieve such uniform fit
and good
tolerances across both of the trays. In this way, the flanges may allow for
some variation
across the top surfaces of the lower tray and the bottom surface of the upper
tray. The
height of flanges may vary depending on the size of the internal space formed
by the
sidewalls of the sifting tray. It may allow for the structural design of the
sidewalls to be
more flexible.
[00041] In use, the stacked trays of the sifting system 100 as shown in
Fig. 5 may
be used as a unitary container to hold a certain amount of a material such as
pet litter
(e.g. cat litter). When a pet has deposited excrement in the litter, its solid
waste and
clumped litter formed by liquid excrement may be separated from the unused
litter by
lifting the top-most tray and agitating or shaking the tray over the remaining
stacked
trays to cause the unused litter to exit through the slots of the top tray and
into the
adjacent lower trays. The solid waste and clumped litter which are too large
to pass
through the slots 22 are left in the tray 10a for discarding. The tray 10a may
be further
cleaned and washed if desired. Because the bottom two trays have slots
arranged in an
interference pattern, the sifted litter stays within those two trays without
going onto the
floor. When the top tray 10a is empty, it is placed on the bottom of the
stacked trays 10b,
10c by placing the tray 10a below the stack, and ensuring that the tray 10a
and the tray
10c are oriented 180 degree to each other. The operation may now be repeated
with
the tray 10b being the top-most tray. Additional litter may be added from time
to time as
desired.
[00042] When the user does not stack the trays correctly as shown in Fig.
7, and
the user does not notice the incorrect orientation, litter will fall through
the slots of the
trays to the ground or floor due to the slots of the upper tray not being
blocked by the
upper base surface of the adjacent lower tray. The structural design and the
cooperation of the protrusions and rim of the sifting tray of the present
disclosure help
indicate to the user that the trays are incorrectly oriented.
[00043] Fig. 7 shows an exemplary view in which the trays 10a, 10b, 10c of
the
sifting system 100 are incorrectly stacked and thus do not properly nest
together. The
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view indicates that the trays 10b and 10c are not turned 180 degree to each
other when
the tray 10c is placed back below the stacked trays 10a, 10bc after its use.
As a result,
the protrusions 26b of the tray 10b on its opposing sides fall on the top face
of the rim
16c and the tray 10b is thus lifted a certain height away from the tray 10c.
Since the
protrusions 26b each have a pointed end, which results in that the tray 10b
rocks or
shakes back and forth when the stacked trays are in use, and that the tray 10a
also
becomes tilted on its surface. This will help bring the incorrect orientation
to the user's
attention.
[00044] Fig. 9 shows another embodiment of the sifting tray 40 according
to this
disclosure. The sifting tray 40 is similar to the sifting tray 10 of Fig 1.
Rather than an
asymmetrical lip, the rim 42 has a rim aperture 48 on its surface at each of
its opposing
sides 50. The dimension of the aperture 48 corresponds to that of the
protrusion 46
such that, when another substantially identical sifting tray 40 is stacked on
the top by
turning 180 degree, the protrusion of the upper tray can pass through the rim
aperture
48 of the lower tray. If the trays are not correctly oriented, however, the
protrusion does
not pass through the aperture 48 and instead hits to the rim 42 resulting in
the top sifting
tray not nesting properly in the bottom sifting tray.
[00045] Fig. 10 shows another embodiment of a sifting tray 60 according to
the
present disclosure. The sifting tray 60 is similar to the sifting tray 10 of
Fig. 1. Rather
than an asymmetrical lip, the rim 62 of the sifting tray 60 has a notch 64 at
its edge at
each of its opposing sides 68. The dimension of the notch 64 corresponds to
that of the
protrusion 66 such that, when another substantially identical sifting tray 60
is stacked on
the top by turning 180 degree, the protrusion of the upper tray can pass
through the rim
notch 64 of the lower tray. If the trays are not correctly oriented, however,
the
protrusion does not pass through the notch 64 and instead hits to the rim 62
resulting in
the top sifting tray not nesting properly in the bottom sifting tray.
[00046] Fig. 11 shows another embodiment of the sifting system 400
according to
the present disclosure. The sifting system 400 as shown comprises three
substantially
identical sifting trays 40a, 40b, 40c as discussed above and illustrated in
Fig. 9, in which
the three sifting trays 40a, 40b, 40c are stacked one on top of another and
each upper
tray is nested stably in its adjacent lower tray without interference from
each other. The
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sifting system 400 is similar to the sifting system 100 except for the
placement of the
protrusions 46a, 46b. In this embodiment, the protrusions 48a of the sifting
tray 40a is
received and held in the aperture 48a of the sifting tray 40b, and the
protrusions 48b of
the sifting tray 40b is received in the aperture 48c of the sifting tray 40c.
Protrusions
which fit snugly into the apertures can help firmly hold together the stacked
trays to
inhibit the trays from shaking or moving when the pet climbs into or out of
the top tray or
moves around in the stack of trays. In an embodiment, the protrusions 46a,
46b, 46c of
may be located on the rims of the trays at a position such that the
protrusions 46a and
46b of the top tray 40a and the middle tray 40b, respectively, are received in
apertures
48a, and 48b, respectively. Referring to the tray 40 in Fig. 9, for example,
the distance
H5 should be equal to the distance H6. In another embodiment, the protrusions
66 of
any upper tray may be received and held in the notch 64 of another adjacent
lower tray
60. The engagement of the protrusions and the notch can hold together the
stacked
trays firmly and stably and can prevent each of the trays in the sifting
system from
shaking or moving when the pet climbs into or out of the top tray or moves
around in it.
The above-specified requirements for the arrangement of the aperture 48 and
the
protrusion 46 as shown in Fig 9 also apply to that of the notch 64 and the
protrusion 66
in Fig. 10.
[00047] Figs. 12 and 13 show embodiments of a flange bridge 72, 74 in
accordance with this disclosure. A bridge 72,74 connects two adjacent flanges
24
together. The bridges 72, 74 may be a rib. The bridge may be thin portions of
plastic.
The bridges 72, 74 may be formed at the same time as the entire tray. Bridge
thickness
may be thinner than the thickness of the flanges wall. The bridges 72, 74 may
extend
from the external wall of one flange 24 to that of the other flange 24. The
flanges 24
connected by the bridges 72, 74 may be on opposite lateral sides of the tray,
or on the
same lateral side of the tray. The height of the bridge 72, 74 relative to the
flange walls
may vary. Bridges can help stiffen or strengthen a tray. Bridges can be
especially
helpful when the base of the tray is very thin. Reducing the thickness of the
base helps
reduce the overall weight of the tray and the amount of materials used in the
tray. This
can help reduce material, production, and shippings costs. Lower tray weight
can also
make it easier for a user to lift a tray and sift the litter therefrom during
using. The
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bridges 72, 74 may also help a tray to resist deformation of the base, such as
along the
centre line of the tray. The tray is used to sift pet litter, which may
comprise aggregate ¨
a heavier material. Furthermore, the bridges 72, 74 can help improve tray base
flatness
and inhibit tray base bowing during the injection molding and/or manufacturing
process,
and reduce cooling time. When a molded tray part cools after injection
molding, it
typically shrinks. Shrinking of the walls of a tray inward can cause the base
of the tray to
warp or bow as it is contracted. Trays are most susceptible to warping between
the
flanges where the material is thin. Bridges 72, 74, help resist this warping
or bowing by
providing lateral support against the flanges. Consequently, the time required
to cool a
tray may be shortened since bridges 72, 74 inhibit the tray base from warping
if the tray
is allowed to cool rapidly.
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