Abstrict A prism shaped in the form of a truncated obround, has one end
defining an aperture through which a cat can enter. Internally,
the hedron defines a plenum but transcending through a sector of
the hedron, the plenum is sub-divided into a first and second sub-plenum
by a sieve preferably in the shape of a plurality of spatially disposed
parallel slats extending from front to rear. On the upper margin
of the sieve is a collection station adapted to collect solid and
urine saturated waste from a cat. The interior of the hedron is
partially filled with granular cat litter and on defecation of a
cat, the solid and urine saturated waste are consumed, in part,
by the cat litter. On rotation in one direction and counter-rotation
in the other direction, the cat litter is passed through the sieve
into the second sub-plenum while at the same time, the solid waste
and urine saturated waste pass over the screen into a collection
station where they are collected on the moment of counter-rotation
which step also causes the clean cat litter in the second sub-plenum
to flow back into the first sub-plenum which is in communication
with the aperture.
Claims I claim:
1. A litter box for separating animal wastes from litter material
comprising:
an enclosure defining a plenum and shaped as a truncated obround
with a planar truncation side; a semi-circular side opposite said
truncation side; planar, substantially parallel top and bottom surfaces;
and planar, substantially parallel front and rear ends;
dividing means vertically disposed in said enclosure between said
truncation side and said semi-circular side and extending horizontally
from said front end to said rear end for dividing said plenum into
first and second sub-plenums; said first sub-plenum being located
between said truncation side and said dividing means and said second
sub-plenum located between said separation means and said semi-circular
side; said dividing means including a separation grill adjacent
said bottom face for separating animal wastes from the litter material;
an aperture in said front end sized to permit passage of a cat
into and out of said first plenum; and
an imperforate collection tray disposed within said first sub-plenum
above, and adjacent to said separation grill;
whereby, in use, the litter box is positioned such that the bottom
surface rests upon a floor with litter material disposed within
the first sub-plenum and after usage of the litter box by the cat,
the litter box is rotated in a first direction by rolling the semi-circular
side upon the floor until the top surface is resting upon the floor
thereby causing the litter material to pass through the separation
grill into the second sub-plenum while animal wastes are separated
therefrom and retained in the first sub-plenum, and thereafter the
litter box is rotated in a second, opposite direction by rolling
the semi-circular side upon the floor until the bottom surface is
again resting upon the floor thereby causing the litter material
to pass back through separation grill and into the first sub-plenum
while the animal waste is deposited and retained in the collection
tray.
2. The litter box as set forth in claim 1 wherein said separation
grill comprises a plurality of inclined slats spatially disposed
from one another so that the litter material may freely pass therethrough
while wastes are retained thereby.
3. The litter box as set forth in claim 1 wherein said separation
grill lies in a substantially vertical plane and comprises a plurality
of inclined slats spatially disposed from one another so that the
litter material may freely pass therethrough while wastes are retained
thereby; said slats extending longitudinally from said front end
to said rear end of said enclosure and being disposed at an angle
of inclination of about 30 degrees relative to the plane of said
separation grill.
4. The litter box as set forth in claim 1 wherein said front end
of said enclosure includes an opening and said collection tray is
received in said opening, whereby said collection tray may be readily
removed from said enclosure and emptied.
5. The litter box as set forth in claim 1 wherein the collection
tray comprises a longitudinally disposed tray having an upper side
edge, and said litter box further includes means for holding said
tray in juxtaposition above said separation grill with said upper
side edge of said tray held against said semi-circular side of said
enclosure.
Description This invention relates to a litter box for cats.
BACKGROUND TO THE INVENTION
Various proposals over the years have been suggested for the purposes
of creating an apparatus for the mechanical separation of cat solid
waste randomly buried in cat litter. The cat litter is generally
entrained not only with the solid waste but is saturated with cat
urine waste that coalesces the cat litter into clumps. Separating
the urine clumps of waste and solid waste is not an enjoyable task.
Various proposals have been proposed. For instance, PIERSON in
U.S. Pat. No. 4846104 issued 17 Oct., 1978 discloses an AUTOMATED
CAT TOILET featuring a rotary drum with an internal sieve member
that is a fixed member within the cylinder and on rotation of the
cylinder, passes through the cat litter to collect the solid waste
and the clumps of saturated urine litter and upon further spinning,
discharges them out of the cylinder into a collection region or
tray beneath the same.
CARTER in U.S. Pat. No. 1128264 issued on 17 Oct., 1978 discloses
a SANITARY FACILITY FOR PETS, being a rotatable drum chamber that
accomplishes the same.
These inventions are cumbersome, have moving parts, and are expensive.
THE INVENTION
I have conceived of a prism or hedron that, in lateral cross-section,
is a truncated obround and having at one end, an aperture through
which a cat can enter. Internally, transcending through a sector
of the hedron is a sieve, which partitions the hedron into two communicating
sub-plenums. The sieve therefore extends from a lower peripheral
side of the obround toward the other parallel side of the obround.
The sieve is a plurality of parallelly disposed and inclined spatially
disposed strips or slats and a removable collection means or tray
slidingly insertable at the upper end of the screen so as to periodically
collect the solid waste or saturated urine litter clumps, after
a self-contained litter cleaning, or sieving step, is performed
in a fashion that will become apparent.
Particularly, rotation clockwise and counter-clockwise steps are
needed in order to rotate the hedron, along its longitudinal axis,
in either direction, one direction causing the separation from the
granular or loose cat litter, of urine saturated litter clumps and
solid wastes from the loose litter, conveying the separated items
from the loose litter into a collection bin, and on counter rotation,
placing the collection bin at an upper elevated position so that
it may be removed and the contents discarded and then the collection
bin for tray re-insertion.
In this respect, it is contemplated that the collection tray be
located entirely within the housing or hedron but is removable therefrom
so that its contents can be removed.
The invention has particular advantage, over the prior art, in
that there is a mechanical separation of the clumps and solid waste,
from the granular cat litter, but without using automated motors
or machines, gears and the like, which substantially increases the
costs, as noted in the earlier prior art cited, and also does not
require chemical separation.
One of the features of the invention is to provide, along a core
of the semi-circle, a slatted grill which acts as the sieve to segregate
the loose litter from the urine saturated clumps and the solid wastes
and that also conveys the lateral two into the removable collection
tray and that acts as a wall which holds the clean litter in the
second plenum location when in the inverted position.
The invention therefore contemplates a cat litter box adapted to
provide a station for cat litter and for cleaning the litter of
solid waste and urine saturated litter waste arising from defecation
of a cat, and for depositing the same in a collection station comprising
a hedron, defining a plenum, having opposite ends with an outer
convex surface and a truncated side surface, one of the ends defining
an aperture sized to accommodate the passage of a cat into and out
of the hedron, a slatted grill means mounted within the hedron,
partitioning the plenum into a first and a second sub-plenum, the
first sub-plenum communicating with the aperture, the screen means
adapted to pass cat litter through the same for temporary storage
in the second plenum and a removable collection station communicating
with said first plenum mounted adjacent said slatted grill and adapted
to receive the solid waste and urine saturated waste on rotation
of the hedron in one direction during which time the cat litter
passes through the slatted grill into the second sub-plenum, and
on counter-rotation of the same, causes the thence clean cat litter
in the second sub-plenum to pass back into the first sub-plenum.
Particularly, the litter box is a truncated obround and the slatted
grill has a spacing of about No. 6 to 8 but preferably is composed
of a family of spatially disposed parallel inclined slats. Additionally,
a removable collection tray is positioned at a collection station
adjacent to the screen to capture waste, as will become apparent.
The invention further contemplates a method of cleaning cat litter,
of solid waste, and urine saturated waste, comprising the steps
of selecting a hedron which has one convex side, and an aperture
in one end adapted to accommodate the passage of a cat into and
out of the hedron, the hedron defining a plenum, partitioning the
plenum with a slatted grill into a first and second sub-plenum,
placing at one upper end of the screen, a waste collection station,
placing within the plenum cat litter, subsequent to it being soiled
by a cat and rotating the plenum in one direction to clean cat litter
into the second which is held in location because of the slats,
thence, counter rotating the hedron so as to cause re-pass of the
cat litter from the second plenum into the first while at the same
time, depositing solid waste and urine saturated waste in the collection
station .
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described by way of example and reference
to the accompanying drawings in which:
FIG. 1 is a perspective view of the prior art;
FIG. 2 is a perspective view of the embodiment of the invention;
FIG. 3 is an x-ray view of the interior, and side elevational view,
of the litter box according to FIG. 2;
FIGS. 4A through 4E are respective sections along IV--IV of FIG.
2 FIG. 4A showing the rest position of the litter box, according
to the invention, for the purposes of receiving cat waste; FIGS.
4B through 4E being successive rotational positions of the litter
box of FIG. 2 showing the separating and cleaning of the litter,
of the saturated urine clumps and of solid waste from the balance
of the litter.
FIG. 5 is a perspective view of the collection tray removal step
of urine saturated clumps and solid waste, after the cleaning steps
by counter-rotating from FIG. 4E through and back to FIG. 4A.
FIG. 6 is a rear perspective view of an alternative embodiment
showing a rear surface removable deodorizer.
Referring to FIG. 1 and the prior art, there is demonstratively
shown a litter tray (10), according to the prior art, containing
cat litter (11) and cat (6) performing its duties therein.
Referring to the preferred embodiment of the invention and FIG.
2 a hedron is generally shown as (20) and in lateral cross-section,
is shaped as a truncated obround with a straight planar truncation
side (21), a semi-circular opposite surface (22), flat straight
top and bottom surfaces (2324), the latter two of which are respectively
parallel to each other; a forward and rearward flat faces or ends
(25) and (26). Although described as a truncated obround, the hedron
might be a semi-circular, in section, cylinder because it will be
apparent hereafter that the semi-circular opposite surface (22)
makes it most convenient for clockwise and counter-clockwise rotation
of the hedron in order to "sieve" and to separate from
the granular cat litter, solid waste and urine saturated waste that
coalesces with the litter. The forward and rearward faces or ends
(25) and (26). The forward face or end (25) defines a cat accommodating
aperture (27) with an outwardly extending slightly downwardly inclining
peak (28) extending from the upper portion of the perimeter of the
aperture (27). A collection tray handle (29) extends from a collection
tray (30) front end (30') that extends through an aperture (27)
defined in the front face (25). The tray front end (30') is but
one end of a collection tray, more clearly seen in FIG. 5 and referenced
as (30), and consists of a longitudinal element (31) formed with
a U-shaped lateral cross-section, as more clearly seen in FIGS.
4 the upper perimeter (32) which is rectangular, in plane, and
provides means for collection of the solid waste (40) and clump
waste (41) entrained in the granular litter (42), as will be described.
Referring to the perspective views of FIGS. 2 and 5 in the upper
left-hand corner of the obround hedron (20), and extending from
front face (25) to the rear face (26) is a handle (H) which assists
in the rotation and counter-rotation of the litter box (20) so as
to accomplish the cleaning steps, depicted in FIGS. 4A through 4E.
In that respect, the outer profile of the hedron steps through a
concave surface (C) to a accommodate the handle (H). It will apparent
to those skilled in the art that the handle (H) need not extend
the full length of the litter box but may be truncated so as to
only extend either from the front face (25) rearward or from the
rear face (26) forward some distance so as to provide a gripping
region for one's hand by which the rotation of the litter box may
be easily accomplished.
Referring to FIGS. 4A through 4E and particularly 4A, within the
litter box (20) is a screen (35) which extends from the front face
(25) to the rear face (26) and consists of a plurality of parallel
rectangular strips or slats (36), spatially disposed about 1/3 of
an inch to 1 inch (0.8 cm to 2.54 cm), preferably 1/2 inches, one
from the other, and having a width, of each slat, of about 3/32
inch (0.24 cm), although this dimension is not critical, and an
inclination at an angle relative to the plane of the screen of about
30.degree. in the fashion shown so as to provide a longitudinal
inclined aperture (37) between each adjacently disposed slats (36).
When this slat size and space is used, this translates into a slatted
grill with spacing of approximately No. 7 but generally in the range
from about No. 6 to No. 8. The slatted grill (35) extends vertically
along the diameter of the semi-circular face (25) of the obround,
as most clearly seen in FIGS. 4 to an extent of little over 50%
or 60% of the diameter, thence, steps into an L-shaped portion having
a bottom tray-supporting surface (38) and an upward extending side
(39). The inner surface of the obround end surface (22) has a glide
rail (50) extending from the inner side of the obround (22), from
front face (25) to back face (26). The tray (30) has its right-hand
upper margin (32) of such length or height so as to slide between
the glide rail (50) and the inner surface of the obround end (26).
The glide rail (50) is slightly inclined so the tray side margin
(32') engages between the glide rail and the inner side of the opposite
semi-circular surface (22). By judicially selecting the dimension
of the bottom tray-supporting surface (38) and the upward extending
side (39) relative to the height of the perimeter (32) to the bottom
of the tray (30), the same is "locked in" when fully pushed
into the litter box (20). If the forward face cat accommodating
aperture (26) is configured so that in fact that aperture is contoured
and has marginal upper notches (29') and (29"), these notches
will accommodate the upper longitudinal perimeter (32) of the tray
(30) and hence, "lock the tray" into position onto the
tray-supporting surface (38) and the upward extending side (39).
On rotation of the litter box (20), the tray is fixedly held there
and will collect the waste in the following fashion.
Referring to FIG. 4 the litter is generally shown as (40) and
consists of solid waste (41) and clump waste (42). On rotation and
referring to FIG. 4B, the litter (40) begins to pass through the
slatted grill (35) while the solid waste and urine saturated clumps
(41) and (42) sit on the upper surface of the slatted grill (35),
as shown in FIG. 4B. On further rotation, and now referring to FIG.
4C, the clumps fall to the inner surface of the top side (23) and
all of the litter has passed through the slatted grill (35) so as
to be clean litter (40'). Continual rotation in the clockwise direction
occurs so that the top surface (23) is flush with the ground. Thence,
as counter-rotation begins to occur, and now referring to FIG. 4D,
the solid waste and saturated clumps (41) and 42) slide into the
collection tray (30) and as seen in FIG. 4E, the cleaned litter
(40') slides back through the slatted grill (35) to occupy and become
litter (40), as in FIG. 4A.
Referring to FIG. 4E, the solid portion represents the counter-clockwise
return position of the litter box, according to the invention while
the phantom position illustrates, an overturn on counter rotation
of approximately 15.degree.-20.degree. so that the cat litter (40),
which has now been cleaned, assumes the flat attitude as that of
originally shown in FIG. 3 and 4. In that respect, the bottom corner
or intersection between the truncated side (40) and the bottom surface
(24) should be rounded or convex, as this allows simplistic movement
for the counter rotation overturning.
For deodorizing the hedron, of the smells from defecation, the
back wall, and now referring to FIG. 6 may have a removable deodorizer
tray (D) which can be slipped out of and slipped back into the hedron
since a track is provided in the rear inner surface wall (26) of
the hedron. |