Abstract:
A cat litter box having a base and detachable cover secured to the base. The front portion of the top of the cover and an inwardly and outwardly swinging door attached to the front portion together form a bifolding door for opening the front and a portion of the top of the box for servicing the litter box. The cover when detached from the base nests with the base for storage and shipping the box.

Description:
SUMMARY OF INVENTION 
       [0001]    This invention relates to cat litter boxes. 
         [0002]    The cat litter box embodies one or more of the following improvements that make cleaning and maintenance of the box more convenient, make it easier for the cat to enter and leave the box, employ improved latches to lock the base and cover together; reduce the knock down size of the box while enabling the various parts to be factory assembled, and reduce or prevent the transfer of unpleasant odors from the box to the surrounding area. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0003]    The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings: 
           [0004]      FIG. 1  is a front perspective view of one embodiment of cat litter box in accordance with this invention; 
           [0005]      FIG. 2  is a top plan view thereof. 
           [0006]      FIG. 3  is a cross-sectional elevation view thereof taken along section line  3 - 3  of  FIG. 2 , with the door and roof in the closed position; 
           [0007]      FIG. 4  is a cross-sectional view similar to  FIG. 3  but showing the door in an open position; 
           [0008]      FIG. 5  is a cross-sectional view similar to  FIGS. 3 and 4  but showing both the door and the retractable roof in their fully opened position, providing maximum access to the box interior; 
           [0009]      FIG. 6  is a fragmentary cross-sectional view taken along section line  6 - 6  in  FIG. 2  and showing one of the latches in the unlocked position, that connects the base and top together; 
           [0010]      FIG. 7  is a cross-sectional view similar to  FIG. 6  but showing the latch in its locked position; 
           [0011]      FIG. 8  is a fragmentary top view of the latch shown in  FIGS. 6 and 7 ; 
           [0012]      FIG. 9  is a fragmentary cross-sectional perspective view showing the manner in which the rim structures of the base and cover engage one another; 
           [0013]      FIG. 10  is a fragmentary top perspective view of the front position of the litter box. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    This invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having,” “containing,” “involving,” and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. 
         [0015]    The cat litter box of the present invention includes in its general organization, a base  10 , cover  12  and front swinging door  14 . A cat can push the door open from either the outside or inside of the box so as to easily enter or leave the box interior. The cover includes a top wall  16  having a fixed rear section  18  and a movable front section  20 . The base  10  and cover  12  are releasably connected together by latches  22  disposed on opposite sides  24  and  26  of the litter box. The base  10  includes a bottom wall  30 , front and rear walls  32  and  34  and side walls  36  and  38 . The cover  12 , base  10  and top front section  20  of the box may be made of polypropylene, polyethylene, styrene ABS, or other similar materials. The front door  14  preferably is made of clear ABS, but other similar materials may be used. 
         [0016]    The base  10  has a rim  40  that extends about the top edges of the front, rear and side walls  32 ,  34 ,  36  and  38  and includes a top outwardly extending flange  42  and a downwardly extending skirt  44  spaced outwardly from the front, side and rear walls of the base. The general rim configuration is shown in  FIG. 9 . The rim  40  of the base cooperates with rim  46  on the cover  12  to seat the cover firmly on the base. As described in detail below, the rim  46  of the cover carries a latching mechanism  48  for detachably locking the base and cover together. The rim  46  includes an outwardly extending flange  50  and a skirt  52  that engage the upper surface of the flange  42  and outer surface of skirt  44  of the base rim  40 . 
         [0017]    As shown in  FIGS. 3-5  and  9 , in one embodiment, the side wall  38  has a step  54  spaced a short distance from the top of the wall to create a recess  56  on the inside of the upper end of the side wall, which recess receives the lower ends  58  of the side and back walls of the cover  12 . This structure preferably extends continuously along the side and rear walls of the base and cover and further extends onto the side portions  60  of the front wall. 
         [0018]    As shown in  FIGS. 3-5 , the bottom wall  62  of the base  10  carries a small platform  64  that tilts the base slightly downwardly toward the front wall  32 , that causes litter (not shown) deposited in the base to spill toward the front of the base to increase the litter depth in the area beneath and behind the door  14 . 
         [0019]    The bottom  70  of the door opening  72  is defined in part by a lip  74  that extends inwardly of the base. The lip  74  includes recesses  76  at its ends (see  FIG. 10 ) that enable a waste bag (not shown) to be hooked over the lip so that the bag may be held securely in place with only one hand and a person cleaning the box may scoop up and/or sift the litter and deposit the waste material in the bag. The base  10  has a large radius at the lower rear corner  80  of the rear wall  34 , particularly as shown in  FIGS. 3 ,  4 , and  5 . This shape makes it easier to sift the litter as it helps to tumble the waste when the litter is scooped. 
         [0020]    In FIGS.  1  and  6 - 8  the latch  22  that locks the base  10  and cover  12  together is shown in detail. The rims  40  and  46  of the base and cover have recesses  90  and  92  in their respective flanges  42  and  44  that closely nest with one another when the cover is placed on the base and together accommodate the latch. The recess  92  is longer than the latch  94  enabling the latch to move longitudinally in the recess on its supports  96  and  97 . The latch carries a pair of L-shaped catches  98  that extend through slots  100  in the recess  92  provided in the flange  50  of the cover rim  46 . Similar slots  102  are provided in the flange  42  of the base recess  90 , and the catches  98  extend through the slots  102  as well when the cover is placed on the base with their respective rims engaged. In  FIG. 6  the L-shaped catches  98  are shown extending through the slots  100  and  102  in the flange  42  of the base, but the catches do not engage the margins of the slots  102  and, therefore, the catches are not engaged and do not prevent separation of the base  10  and cover  12 . When the latch  94  is moved to the right as viewed in  FIG. 6  so as to assume the position shown in  FIG. 7 , the L-shaped catches  98  engage and underlie the margins of the slots  102  so as to prevent separation of the cover  10  and base  12 . As shown in  FIG. 8 , a symbol or symbols such as a lock  103  may be carried on the surface of the recess  92  to indicate the locked and unlocked positions of the catch. 
         [0021]    As shown in  FIGS. 1 and 8  the latch  94  includes a vertical side wall  104  that extends over the skirt  52  of the rim  46  of the cover to maintain the position of the latch in the recess  92 . The latch also includes a stippled upper surface  105  (see  FIG. 1 ) to facilitate engagement of the latch to move it between locked and unlocked positions of  FIGS. 7 and 6 . 
         [0022]    The cover  12  includes top wall  16 , side walls  112  and  114 , rear wall  116  and the front door  14 . The side walls  112  and  114  and rear wall  116  in the illustrated embodiment are integrally molded as a single unit along with the rear fixed portion  18  of the top wall. The front portion  20  of the top wall  16  is supported in the closed substantially horizontal position by the inwardly extending flanges  119  at the tops of the side walls  112  and  114  (see  FIGS. 3-5  and  10 ). The front portion  20  of the top wall of the cover and the door  14  are separately molded independently of one another and of the major unitized portion of the cover. The rear portion  18  of the cover top wall includes a recess  122  that houses a handle  124  pivotally supported by a hinge  126  along the front edge thereof (see  FIG. 2 ). The handle, when used, is pivoted upwardly on the hinge into a generally vertical position and extends upwardly from the plane of the top wall  18 . The handle in the embodiment shown includes an opening  128  large enough to comfortably receive the four fingers of the hand so that it may be gripped firmly, and the box may be carried conveniently and comfortably with or without a cat inside the box. 
         [0023]    The front movable section  20  of the top wall  16  of the cover is also pivotally mounted by means of a transverse hinge  130  along the rear edge of the movable section  20  and is disposed in a plane above that of the rear section  18  (see  FIG. 3 ) The hinge  130  enables the front section  20  to pivot about an arc of approximately 180° from the normally closed position shown in  FIGS. 3 and 4  to the open position shown in  FIG. 5 . 
         [0024]    The front cover section  20  includes a chamber that removably houses a carbon filter  132 . The carbon filter is exposed through a decorative opening  134  in the top surface  136  of the front section  20  and is held in place by a retainer  138  that may be an integral part of the front section. The retainer  138  include a number of openings to allow air to pass through the carbon filter  132  to and from the interior of the litter box. The filter may be held in position by a fastener  140  that passes through the filter and is connected to the retainer. The retainer is perforated so as to allow the flow of air to and from the interior of the litter box. The filter removes odor carrying material from air flowing from the interior of the box to the surrounding atmosphere. 
         [0025]    Another transverse hinge  144  is incorporated into the cover top wall  16 . The hinge supports the door  14  and allows it to swing freely both inwardly and outwardly from its normal, substantially vertical, closed position and also allows the door to swing to a position above front section  20  of the cover top wall when the front section  20  is pivoted about hinge  130  to the open position lying atop the rear section  18  (see  FIG. 5 ). It is evident from an inspection of  FIG. 3  that access to and egress from the litter box by a cat may easily be achieved with minimum pressure exerted by a cat moving through the door opening in light of the freely swinging door. It is also evident as shown in  FIG. 5  that access to the interior of the box for servicing or cleaning may easily be achieved without removing the top from the base simply by inverting the front section  20  of the cover so that it lies upon the rear section  18  and collapsing the front door  14  on the top of the undersurface of the open front section  20  as illustrated in  FIG. 5 . 
         [0026]    The cat litter box described above has many advantages. The folding door in combination with the folding front section of the top wall of the cover provide a unique way to access the litter for maintenance, without removing the entire cover  12  from the base  10 . The door  14  hinged to the front section  20  of the top wall  16  of the cover that in turn is hinged to the rear portion  18  of the cover enables both the door and the front section  20  of the top wall to fold together and stack on top of the rear section  18  of the cover (see  FIG. 5 ). The large resulting opening through both the front and top of the box provides very substantial convenience for the person cleaning the litter box. The lip  74  on the front of the base  10  that protrudes inwardly toward the box interior provides a wide hook-like connector to engage an edge of the open end of a trash bag so that the person cleaning the litter box can hold the bag securely in place with one hand and have the other hand free to hold a scooper to sift the litter and brush the cat&#39;s waste inside the bag. 
         [0027]    The design of the litter box enables the cover, when inverted, to telescope into the base so as to reduce shipping costs and the space necessary for storage. Furthermore, the product design allows all of the components of the cover such as the folding top wall  20 , front door  14 , side latches  22  and handle  124  to be preassembled by the manufacturer, and the cover with all of those preassembled parts nests conveniently inside the base  10 . 
         [0028]    The large radius  80  at the rear of the base causes the waste with the litter to tumble when the litter is being sifted with the aid of a scooper. 
         [0029]    The back of the base being higher than the front retains horizontally projected urine in the base and avoid contact with the cover. Moreover, the mating profile of the cover and base rims preclude urine from leaking out of the box. 
         [0030]    The sliding latches on the opposite sides of the box securely hold the base and cover together even when the box is being carried by the handle. 
         [0031]    Having thus described several aspects of this invention, it is to be appreciated that various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description and drawings are by way of example only.