Abstrict A cat litter box has a tray having a bottom from which sides upwardly
extend to an upper lip and a lid for the tray which has a top from
which sides downwardly extend to a lower lip configured to be supported
upon the tray upper lip. The lid sides are formed with an opening
through which cats may come and go. A ramp having a rough litter-dislodging
surface is mounted in the tray extending upwardly from adjacent
the tray bottom to adjacent the lid side wall opening.
Claims What is claimed is:
1. A cat litter box comprising a tray having a bottom from which
sides upwardly extend to an upper lip, a lid for said tray having
a top from which sides downwardly extend to a lower lip configured
to be supported upon said tray upper lip, said lid sides being formed
with an opening through which cats may pass, and a ramp having a
rough litter-dislodging surface mounted in said tray extending upwardly
from adjacent said tray bottom to adjacent said lid sides opening,
and said tray bottom has a bottom area and is substantially rectangular
and said lid top has an area less than said tray bottom area and
is substantially pentagonal whereby a corner portion of the tray
interior is exposed from above.
2. The cat litter box of claim 1 wherein said lid side opening
is located adjacent said exposed tray corner portion.
3. A cat litter box comprising a tray having a bottom upon which
litter may be spread and a lid removably mounted upon said tray,
said lid having an opening through which a cat may pass, and a walkway
with a rough litter dislodging surface mounted in said tray that
has a substantially level landing field portion located adjacent
said opening from which an extension portion extends, and an upright
barrier mounted on said walkway beside said level landing field
portion to prevent a cat from bypassing said walk extension portion
in exiting the box from the tray bottom.
4. The cat litter box of claim 3 wherein both said walkway landing
field portion and extension portion have a rough litter dislodging
surface.
5. The cat litter box of claim 3 wherein said walkway is removably
mounted in said tray.
6. The cat litter box of claim 5 wherein said tray has a support
upon which said walkway is replacebly mounted.
7. A cat litter box comprising a tray having a bottom from which
sides upwardly extend to an upper lip, a lid for said tray having
a top from which sides downwardly extend to a lower lip configured
to be supported upon said tray upper lip, said lid top being smaller
than said tray bottom whereby a portion of said tray is exposed
with the lid supported upon the tray, and where one of said lid
sides is formed with an opening thorough which cats may pass, said
lid one side said being adjacent said tray exposed portion, and
a ramp having a rough litter-dislodging surface mounted in said
tray extending upwardly from adjacent said tray bottom to adjacent
said lid side opening.
Description TECHNICAL FIELD
This invention relates to cat litter boxes.
BACKGROUND OF THE INVENTION
Cat litter is widely used today to provide absorbent material for
cat waste, i.e urine and feces. The litter is housed in a litter
box or tray. The litter boxes often are covered for aesthetics and
odor reduction with entry being had by a side opening in the cover.
A persistent problem with the use of cat litter boxes and trays
is that of cats tracking litter onto the floor or carpet when leaving
the litter box. Over the period of a day or two a significant amount
of unsightly litter typically accumulates near the box. Attempts
at training cats to wipe their paws upon leaving the box are useless
due to their independent nature.
Heretofore I addressed this problem by inventing a threshold for
a covered type cat litter box having a side entry as shown and described
in U.S. Pat. No. 5924383. The threshold comprised a stand that
supported an elevated cat landing field, a ramp having a rough litter-dislodging
surface that extended down from the landing field, and a barrier
in the form of a cover for barring cats from jumping onto or off
the sides of the ramp. By setting the threshold with the ramp accessible
to the litter box entry, cats could ingress and egress the box only
via the threshold rough litter-dislodging ramp and the landing field.
I have since found that cats are often hesitant to enter a litter
box through such a threshold. Apparently some find the covered ramp
to be a tunnel with an uncertain end that they cannot see until
they have jumped up onto the landing field. Moreover, the presence
of the threshold, which juts out from the litter box, places the
litter further away from the entry. This in turn makes the litter
odor weaker and thus less attractive. The addition of the threshold
also enlarges the overall litter box, the presence of which is usually
considered a necessary evil.
Accordingly, it is seen that were a litter box to be devised without
the just mentioned disadvantages of an add-on threshold, and yet
with the advantage it provides in dislodging and collecting litter
from the paws of departing cats, rather than have such tracked about,
a definitive advance would be achieved. It thus is to the provision
of such that the present invention is primarily directed.
SUMMARY OF THE INVENTION
In a preferred form of the invention, the new cat litter box comprises
a tray having a bottom from which sides upwardly extend to an upper
lip and a lid for the tray has a top from which sides downwardly
extend to a lower lip configured to be supported upon the tray upper
lip. The lid sides are formed with an opening through which cats
may come and go. A ramp having a rough litter-dislodging surface
is mounted in the tray extending upwardly from adjacent the tray
bottom to adjacent the lid side wall opening.
In another preferred form the cat litter box comprises a tray having
a bottom upon which litter may be spread. The box has a lid removably
mounted upon the tray which has an opening through which cats may
pass. A walkway with a rough litter-dislodging surface is mounted
in the tray. The walkway has a substantially level landing field
portion located adjacent the lid opening from which an extension
portion extends. An upright barrier is mounted on the walkway beside
the level landing field portion to prevent a cat from bypassing
the walkway extension portion in exiting the box.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of a cat litter box that embodies
principles of the invention in its preferred form.
FIG. 2 is an exploded view of the cat litter box shown in FIG.
1 with its lid and ramp shown separated from its tray.
FIG. 3 is a cross sectional view of a fragment of the lid shown
seated upon the tray.
FIG. 4 is a cross sectional view of the lid handle.
DETAILED DESCRIPTION
With reference next in more detail to the drawings, there is shown
a cat litter box 10 of molded plastic construction which has a tray
11 a lid 12 and a walkway 13. The tray 11 is generally rectangular
and has a bottom 15 from which four sides 16-19 upwardly extend.
The sides 18 and 19 are seen to have a slight inward jog adjacent
the tray corner shown in the foreground. The tray is also molded
with an interior ledge 20 that extends level along the jog portion
of side 18 and level along the jog portion of side 19. At the end
of the jog it too widens and descends (not viewable) to the tray
bottom 15. The top of the tray sides is formed with a lip or ridge
21 the details of which are shown in FIG. 3.
The cat litter box lid 12 has a flat top 31 of pentagonal shape
in which a handle 32 is formed. The handle, an enlarged view of
which is shown in FIG. 4 has two semispherical recesses 33 that
straddle a bridge 34. The handle is used by placing a thumb in one
recess and a finger or two in the other and gripping the bridge.
The lid also has five sides 36 that depend from the top 31. The
bottoms of these sides are formed with a flange 37 the details
of which are best shown in FIG. 3. The flange is sized to fit snugly
over the tray ridge 21 in removably mounting and securing the lid
upon the tray. One of the lid sides 36' is seen to be formed with
a large opening through which a cat may pass. Alternatively, that
side may be completely open. Since side 36' cuts cata-cornered across
the tray where sides 18 and 19 join, the area of the lid top 31
is less than the area of the tray bottom 15. This adds to the ease
in which a cat may ingress and egress from the box.
The cat litter box walkway 13 is seen to have a level landing field
portion 41 from which an inclined ramp portion 42 extends. Each
is constructed of a rough, open grating through which litter may
fall. The walkway has an upright side 43 that extends along one
side of portions of the landing field and ramp. The walkway is sized
to be set upon the ledge 20 of the tray with its bottom end tucked
within a recess 44 and with its other end tucked through a slot
45 under the ridge 21 of tray wall 18. As the walkway is a little
resilient, it can be flexed slightly in inserting and extracting
it from the recess 44 and slot 45.
For use the landing field 41 is very accessible to a cat since
much of it is unsheltered by the lid. Litter odor may also easily
flow to this area over the walkway side 43 to further entice the
cat. Thus a tunnel effect is substantially avoided. When a cat leaves
the box it must walk up the ramp to jump off the landing field.
Both of these movements upon the grated surface of the walkway serve
to remove litter from the paws which falls through the grating to
the bottom of the tray. For filling, cleaning and refilling the
lid and runway may be easily removed from the tray and then remounted.
It thus is seen that a cat litter box is now provided which is
of a compact, sightly construction and yet which is effective in
removing litter from exiting cat paws without hindering cat entry.
It is also simple to fill, refill and clean. Though the box has
been shown and described in its preferred form it should be understood
that many modifications, changes or additions may be made without
departure from the spirit and scope of the invention as set forth
in the following claims. |