Odor free litter system

An improved sifting type pet waste receptacle, commonly known as a litter box, for separating both solid and liquid pet waste from clumping type litter material. It includes at least two solid bottomed pans with a vertical wall portion and an open top, plus at least one sifting device having a perforated bottom portion with a vertical wall portion and an open top. The bottom portion of the solid bottomed pans also include a plurality of projections to prevent clogging of the perforations in the sifting device. Also included is a spill rim to help contain litter material which may be thrown out during digging and/or covering by the pet, with a disposal door added to the vertical wall portion to prevent pet waste from being spilled during disposal.

DETAILED DESCRIPTION 
Referring to FIG. 1, a perspective view of the preferred embodiment of the 
invention designated therein by the numeral 10, is shown. The invention 10 
is designed for use with clumping cat litter only, so that both liquid and 
solid pet waste may be completely removed on a daily, or at least very 
frequent basis, thus eliminating odor and bacteria while extending the 
useful life of the cat litter material and providing far greater 
convenience than similarly designed inventions. 
The invention 10, has two nestably interchangeable receiving pans 12 and 
14, both comprising a solid bottom portion 16 and 18, both having a 
plurality of projections 20 and 22, on said bottom portion 16 and 18, 
respectively. The vertical wall portion 24 and 26, of the receiving pans 
12 and 14, have an integrally formed rim 28 and 30, which have integrally 
formed handles 32 and 34, which mutually oppose each other for gripping 
the componants when lifting one out of the other during the sifting 
procedure. Said handles 32 and 34, are positioned at a distance of one 
half of the total length of the handles from the center of the length of 
the wall portion 24 and 26, in order to provide space for gripping any one 
of the componants. Further, when one of the receiving pans 12, is turned 
180 degrees and nestably placed inside the other, the edge of the handle 
nearest the center 36, of the wall portion 24, will align with the edge of 
the handle nearest the center 38, of the wall portion 26, of the remaining 
receiving pan 14. Because each of the receiving pans 12 and 14, are 
substantially identical, this positioning of the handles previously 
described, is also interchangeable or reversible, making it insignificant 
which one of the receiving pans is turned. 
A third nestable receptacle 40, has a perforated bottom portion 42, the 
perforations 44, are arranged to interengage the projections 20 or 22, of 
the receiving pan 12 or 14, in which it is selectively nested, thus 
filling the cavities otherwise created if projections 20 or 22, did not 
exist, as is shown in FIG. 3. The third receptacle 40, serves as the 
sifting tray for separating the pet waste from the clumping litter 
material. The vertical wall portion 46, of the sifting tray 40, is 
slightly greater in height than the vertical wall portion 24 and 26, of 
the receiving pans 12 and 14, and has an integrally formed rim 48, with 
integrally formed handles 50, which mutually oppose each other for ease of 
gripping the sifting tray 40, when lifting it out of either of the 
receiving pans 12 or 14, during the sifting procedure. Said handles 50, 
are on dead center of the length of the vertical wall portion 46, so that 
when the sifting tray 40, is nestably placed inside either receiving pan 
12 or 14, half of the handle 50, is unobstructed by the handle 32, of the 
receiving pan 12, in which it is placed, thus providing space to grip the 
handle 50, of the sifting tray 40. 
The fourth component 52, is a removable spill rim for retaining litter 
material which may otherwise be thrown out during digging and/or covering 
by the pet. The spill rim 52, has a vertical wall portion 54, which has a 
disposal door 56, with a locking apparatus 58, which engages the upper 
edge 60, of the vertical wall portion 54. When locked in this open 
position, the disposal door serves to guide the pet waste into the trash 
receptacle or water toilet into which it is being discarded, and prevents 
any pet waste or litter material from being spilled onto the floor. The 
disposal door 56, has a second locking apparatus 62, to engage the rim 48, 
of the sifting tray 40, to hold it closed during pet use. The side 
opposing 64, the locking apparatus 62, of the disposal door 56, is hinged 
to allow opening and closing the disposal door. The spill rim 52, also has 
an integrally formed lip rim 66, which lockingly engages the rim 48, of 
the sifting tray 40, to hold it in place during pet use and during the 
disposal of pet waste. The integrally formed lip rim 66, also has an 
integrally formed notch 68, to allow space for the handles 50, of the 
sifting tray 40, and/or the handles 32 or 34, of the receiving pans 12 or 
14, so that when the clean litter material is reintroduced to the second 
receiving pan which now contains the sifting tray 40, after the pet waste 
has been discarded, the disposal door can alternately be used to guide the 
clean litter material into the receptacle. Further, the lip rim 66, of the 
spill rim 52, is of minimal height, so that when it is lockingly engaged 
with the rim 48, of the sifting tray 40, it does not engage or obstruct 
the rim 28 or 30, of the receiving pan 12 or 14, whichever one the sifting 
tray 40, is selectively placed. The spill rim 52, is open 70, to the 
litter material contained in the sifting tray 40, below. 
In FIG. 2, a side view of the invention 10, is shown with the receiving 
pans, 12 and 14, the sifting tray 40, and the spill rim 52, nestably 
stacked, and engaged. The combined vertical height of the componants is 
substantially low to allow easy access for the pet. In some cases, such as 
small kittens, the use of the spill rim may impede the entry of the pet, 
in which case the spill rim may be removed, and then replaced during 
disposal of pet waste for use of the disposal door. 
FIG. 4 is an exploded cross-sectional view of the disposal door, 56, which 
illustrates the locking apparatus 62, engaging the rim 48, of the sifting 
tray 40. The locking apparatus 62, holds the disposal door closed during 
pet use to prevent litter material from being thrown out during digging 
and/or covering by the pet. This same type of locking apparatus is used on 
portions of the lip rim 66, of the spill rim 52, to hold it in place 
during disposal of pet waste, but is not separately illustrated. 
FIG. 5 is an exploded bottom view of the section of the vertical wall 
portion 54, of the spill rim 52, which is engaged by the the disposal door 
56. It illustrates an overlap 72 and 74, on each side of the opening 76, 
in the vertical wall portion 54, of the spill rim 52. 
To use the invention, a clumping litter material is poured into the sifting 
tray 40, which is nestably placed inside the receiving pan 12, which is 
placed inside the second receiving pan 14, and the spill rim 40, is then 
lockingly engaged on top of the sifting tray. After one day of pet use, 
the the empty receiving pan 14, which is stored under the first receiving 
pan 12, is removed and placed next to the remaining componants of the 
unit. The sifting tray 40, with the spill rim 52, still engaged, is then 
lifted two or three inches above the first receiving pan 12, to to allow 
the clean litter material to sift through the openings 44, into the 
receiving pan 12, while trapping both solid and clumped liquid pet waste 
in the sifting tray 40, for disposal. Immediately following separation, 
the sifting tray 40, is then placed into the empty receiving pan 14, to 
prevent any spilling through the openings 44, of the sifting tray 40. The 
disposal door 56, is then lifted open 180 degrees and locked onto the 
upper edge of the spill rim itself to create a somewhat small opening in 
the vertical wall portion 54, of the spill rim 52. The pet waste is then 
discarded into a waste receptacle of choice, and the disposal door closed 
and locked in its original position. Upon the removal of all pet waste and 
contaminated litter contained in the sifting tray 40, and second receiving 
pan 14, the clean litter material is then poured from the first receiving 
pan 12, into the second receiving pan 14, which now contains the sifting 
tray 40. Once all clean litter has been transferred, the empty receiving 
pan 12, is then stored under the the other receiving pan 14, until next 
use. 
FIG. 6 is a side view of an alternative embodiment of the invention. In 
this embodiment the invention, indicated by the number 100, has a 
plurality of sifting trays 110, having perforations for separating waste 
from litter material, and are nestably placed inside a plurality of 
receiving pans 112, having a ribbed, solid bottom portion. In use, the 
sifting tray is removed, the clean litter poured into the second receiving 
pan which contains the second sifting tray. Then the first sifting tray is 
replaced into the first receiving pan, which are then stored under the 
second sifting tray and receiving pan until next use. 
As demonstrated by the alternative embodiment, changes and/or additions 
could be made to the preferred embodiment which would remain within the 
scope of the invention disclosed herein. The intent of this disclosure is 
merely for illustration and not as a limitation, therefore, the invention 
should be accorded the full scope of the claims.