Abstract:
This application relates to an improved container for holding pet litter. The container has a bottom surface and an outer wall extending upwardly from the perimeter of the bottom surface. The container also has an inner wall coupled to or seated on the outer wall and supported above the bottom surface. The container is partially filled with pet litter to a level below the bottom edge of the inner wall. The inner wall extends adjacent to and inwardly of the outer wall and functions as a urine splashguard, thereby preventing litter clumps from sticking to the outer wall and fouling it. This eliminates the need to dump the entire contents of the container in order to clean the outer wall. In one embodiment of the invention, the inner wall is pivotably and removably coupled to the outer wall. In another embodiment the inner wall has an upper rim which is supported on an upper edge of the outer wall.

Description:
TECHNICAL FIELD 
     This application relates to an improved container for holding pet litter. The invention prevents clumps of pet litter from sticking to the walls of the container. 
     BACKGROUND 
     Cleaning pet litter boxes is an unpleasant and potentially unsanitary chore. Consequently various“self-cleaning” litter containers are known in the prior art to facilitate removal of animal waste and reuse of the container. For example, U.S. Pat. No. 5,752,465, which issued to Page on May 19, 1998, relates to a pet litter holding device which includes a stationary base, a rotatable drum and a sieving panel which isolates solid and clumped litter during rotation of the drum. The waste material is directed to an exit spout adapted to hold a disposable plastic bag. The following United States patents disclose other similar devices for filtering and disposing animal waste: 
     
       
         
               
               
               
               
             
           
               
                   
               
               
                 U.S. Pat. No. 
                 Issue Date 
                 Title 
                 Inventor(s) 
               
               
                   
               
             
             
               
                 5,507,252 
                 April 16, 1996 
                 Waste Separating Cat 
                 Ebert 
               
               
                   
                   
                 Litter Box 
               
               
                 5,749,318 
                 May 12, 1988 
                 Self-filtering Litter 
                 Barbot et al. 
               
               
                   
                   
                 Box for Animals 
               
               
                 5,752,466 
                 May 19, 1998 
                 Clumping Litter Liner- 
                 Lundeen et al. 
               
               
                   
                   
                 Sieve System 
               
               
                 5,799,610 
                 Sept. 1, 1998 
                 Self-Filtering Litter 
                 Poulos 
               
               
                   
                   
                 Box for Pets 
               
               
                   
               
             
          
         
       
     
     Although many reusable pet litter containers facilitate filtering and removal of waste material, they do not eliminate the need for pet owners to periodically clean the walls or sides of the container. Adherence of clumping-type pet litter to container walls is a problem which is common to both conventional and self-cleaning devices. Most cats tend to urinate on or near the end walls or in the corners of litter containers, which are usually rectangular-shaped. Typically it is necessary to use a litter scoop or some other instrument as a scraper to dislodge clumps of pet litter from the container walls. This is an unpleasant job and often results in pet litter plugging the sifter holes of the litter scoop. Moreover, a thin layer of wet litter remains on the container walls which retains odour and is unsanitary. Cleaning is particularly difficult if the container has a litter containment hood which cannot be easily removed. 
     The need has therefore arisen for a pet litter container which is specifically designed to prevent litter from sticking to the walls of the container. 
     SUMMARY OF THE INVENTION 
     In accordance with the invention, an improved pet litter container is disclosed. The container includes an enclosure for holding pet litter, the enclosure having a bottom surface and an outer wall extending upwardly from the bottom surface. The container also includes an inner wall coupled to the outer wall, wherein the inner wall is supported in an upright position within the enclosure at a location above the bottom surface. 
     In a first embodiment of the invention, the inner wall is subdivided into a plurality of separate inner wall sections each of which is pivotably coupled to a portion of the outer wall for movement between the upright position and a folded position. In the folded position the inner wall sections are preferably positioned outwardly of the enclosure. 
     The inner wall sections may also be removably coupled to the outer wall for quick removal and ease of cleaning. Optionally the height of the inner wall above the bottom surface is selectively adjustable. 
     In a second embodiment of the invention the inner wall is formed in one piece. In this embodiment the uppermost portion of the inner wall flares upwardly and outwardly at an angle and then extends horizontally to form a rim which is removably seated on the upper edge of the outer wall. 
     The container may also optionally include a hood for covering the enclosure. The hood is removably connectable to either the outer wall in the first embodiment of the invention or the unitary inner wall in the second embodiment of the invention. The hood includes an opening in a side portion thereof to provide access to the interior of the container. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     In drawings which describe embodiments of the invention, but which should not be construed as restricting the spirit or scope thereof, 
     FIG. 1 is an isometric, partially exploded view of the applicant&#39;s pet litter container and hood assembly showing the inner wall sections in the upright position. 
     FIG. 2 is an isometric view of the container of FIG. 1 showing two of the inner wall sections pivoted to folded positions. 
     FIG. 3 is an isometric, exploded view showing a coupling means for pivotably coupling an inner wall section to the container outer wall. 
     FIG. 4 is a cross-sectional view of the coupling means of FIG. 3 showing the inner wall section moveable between upright and folded positions. 
     FIG. 5 is a longitudinal sectional view of the container of FIG. 1; and 
     FIG. 6 is an isometric view of an alternative embodiment of the invention comprising a unitary inner wall having a rim which is removably seated on the upper edge of the outer wall. 
    
    
     DESCRIPTION 
     As shown in FIG. 1, the applicant&#39;s invention relates to a pet litter container  10  and a removable hood  12 . Container  10  includes a bottom surface  14  and an outer wall  16  extending upwardly from the perimeter of bottom surface  14 . Outer wall  16  may include rounded comers and a flat upper rim  18 . Hood  12  has a peripheral channel  20  which fits on and over rim  18  when container  10  and hood  12  are assembled together. Hood  12  also includes a handle  13  and a door opening  15 . 
     Container  10  further comprises an inner wall generally designated  22  which is coupled to outer wall  16 . In a first embodiment shown in FIG. 1, inner wall  22  is subdivided into separate wall sections  24  which are each pivotably connected to an adjacent portion of outer wall  16 . Wall sections  24  are independently pivotable between upright and folded positions (FIG.  2 ). Each inner wall section  24  includes a first panel  26  and a second panel  28 . When a wall section  24  is in the upright position as shown in FIGS. 1 and 5, first panel  26  extends in a vertical plane and second panel  28  flares outwardly and upwardly at an angle. In the upright position, the bottom edge  30  of inner wall  22  extends above the level of pet litter  32  placed within container  10  (FIG.  5 ). 
     FIGS. 3-5 illustrate “coupling means”, namely a latch assembly  34  for pivotably and removably coupling each inner wall section  24  to an adjacent portion of container outer wall  16 . In particular, a plurality of female slots  36  are formed on outer surface  16  for receiving corresponding male latches  38  connectable to inner wall sections  26 . Each slot  36  is defined between an inner wedge-shaped element  40  and an outer bar  42  which extends between vertical support elements  44 . As shown in FIG. 4, each latch  38  is generally Z-shaped and includes a first end segment  46 , intermediate segments  48  and  50 , and a second end segment  52 . In order to removably couple inner wall sections  24  to outer wall  16 , a first end segment  46  of each latch  38  is inserted into a corresponding slot  36  (FIGS. 3 and 4) where it engages an outer surface  54  of wedge-shaped element  40 . Second end segment  48  is selectively coupled to one of a plurality of spaced-apart fasteners  51  formed on the outer surface of first panel  26  (FIGS.  4  and  5 ). In the illustrated embodiment fasteners  51  comprise a series of narrow, elongated ribs which protrude in parallel from the inner surface of panel  26 . 
     Latches  38  permit pivotable movement of wall sections  24  between the upright position extending inwardly of outer wall  16  and the folded position extending outwardly of wall  16 . As shown best in FIG. 5, in the upright position intermediate section  48  of each latch  38  bears against the outer surface  54  of wedge-shaped element  40  and intermediate section  50  rests on the upper surface of element  40  to support wall section panel  26  in a vertical orientation. The height of each wall section  24  above container bottom surface  14  in the upright position may be adjusted by coupling second end segment  52  of each latch  38  to a selected fastener  51 . In the embodiment illustrated in FIG. 5, wall sections  24  are adjusted to the lowermost height extending a short distance above the level of pet litter  32 . 
     In the folded position shown best in FIGS. 2 and 4, latch  38  is stably supported at a position outwardly of wall outer wall  16 . In particular, one side of first end segment  46  of latch  38  bears against the outer surface  54  of wedge-shaped element  40  and the other side thereof bears against cross bar  42  at the joinder between first end segment  46  and intermediate segment  48  (FIG.  4 ). 
     As will be apparent to someone skilled in the art, other equivalent means for removably and/or pivotably coupling inner wall sections  24  to outer wall  16  may be envisaged. 
     FIG. 6 illustrates a second embodiment of the invention wherein container inner wall  22  is fixed in the upright position and is not subdivided into separate pivotable and removable sections. Inner wall  22  is connected to an upper edge of outer wall  16  by means of a rim  56  that extends around the perimeter of container  10 . In this embodiment the inner wall  16  and rim  56  together form a unitary removable inner wall unit  58 . Rim  56  suspends wall  22  at a position above bottom surface  14  and pet litter  32  (i.e. in an elevated position similar to that shown in FIG.  5 ). In the FIG. 6 embodiment, inner wall  22  is not height adjustable. 
     If a hood  12  is used, the hood peripheral channel  20  (FIG. 1) snaps onto rim  56  of inner wall unit  58  (rather than outer wall  16 ). When inner wall unit  58  and hood  12  are assembled in this manner they may be together lifted clear of outer wall  16 . This facilitates quick removal of inner wall unit  58  for access to pet litter  32 . 
     In use, container inner wall  22  functions as a splashguard in the upright position to prevent cats or other pets from urinating against or near to the inward facing surfaces of outer wall  16 . Container  10  is first filled with pet litter  32  to a level a short distance (typically ½ to 1½ inches below the bottom edge  30  of inner wall  22  (FIG.  5 )). In the first embodiment of the invention described above, pivotable inner wall sections  24  may be moved to the folded position to facilitate pouring of clean pet litter  32  into container  10 . After spreading pet litter  32  evenly, wall sections  24  are then returned to the upright position of FIG.  1 . In the second embodiment described above and illustrated in FIG. 6, inner wall unit  58  and hood  12  may be lifted clear of outer wall  16  (using hood handle  13 ) to permit filling and spreading of pet litter  32 . 
     If hood  12  is used, hood door opening  15  provides the only means for a pet to enter and exit container  10 . Miniature stairs (not shown) may be provided to assist pets in climbing over the raised inner wall  22  at the door opening  15  and into the container  10 . However, such stairs are entirely optional and some pets, such as cats, may prefer to simply climb or hop into container  10  through opening  15  without using the stairs. 
     Although the shape of container  10  is not critical, it is preferable that it be relatively narrow and long as compared to conventional litter boxes. This ensures that, once inside container  10 , cats will be forced to situate their bodies lengthwise so that their rear ends are proximate an end wall of container  10 . This ensures that the pet litter  32  in the mid-portion of container  10 , immediately inside the hood doorway  15 , is never soiled and will therefore not be avoided by cats when entering and exiting container  10 . The position of doorway  15  in the middle of a side rather than in an end portion of hood  12  provides optimum containment of pet litter  32  which may be flung by cats digging or scratching within container  10  (since the length of the cat&#39;s body parallels the length of the container  10 ). 
     The length of container  10  has been increased as compared to conventional litter containers to ensure cats have enough room to feel comfortable. Hood  12  has a width larger than the distance between opposed side portions of inner wall  22  to afford cats a larger turning radius for their heads and tails (which extend above the height of inner wall  22 ). 
     Cats tend to urinate in the end portions of container  10 , either directly into pet litter  32  or against inner wall  22 . The spacing between the bottom edge  30  of inner wall  22  is sufficiently small (FIG. 5) that cats are unable to spray underneath inner wall  22  to outer wall  16 . Inner wall  22  is also sufficiently high such that cats are also unable to spray over its uppermost edge. As explained above, wall sections  24  are height adjustable to suit the habits of particular cats. 
     Cats typically urinate at a downward angle as illustrated by urine spray angle  60  shown in FIG.  5 . In the applicant&#39;s design, the uppermost second panel  28  of each wall section  24  flares outwardly and upwardly (FIG. 1) for optimum urine containment. The outward flaring of second panel  28  in this manner increases the effective height of wall  22 . In order for a conventional litterbox having vertical walls to have the same urine containment feature, the height of inner wall  22  would have to be extended as shown by the evenly spaced dashed lines of FIG. 5 to elevation  62 . The applicant&#39;s design achieves optimum urine containment while still restricting the actual overall height of container  10  to 7½ inches or less for ease of use by most cats. The outward angling of second panel  28  also stops cats from positioning themselves up against the top edge  64  of panel  28 , thereby preventing them from urinating over the top of inner wall  22 . 
     By way of comparison, the contour of a conventional litter-box brim  66  is shown in a broken line composed of dots and long dashes in FIG.  5 . Brim  66  extends inwardly from outer wall  16  and does not take into account urine spray angle  60 . Cats are able to position themselves against the top edge  68  of brim  66  and may urinate over the litterbox wall, especially if the level of litter  32  is high. Other cats may back under brim  66  and urinate against the inward facing surface of the outer wall, resulting in the litter clumping problem described above. 
     Any urine contacting inner wall  22  of the applicant&#39;s invention drips into pet litter  32  within container  10  and is absorbed in the vicinity of wall  22 . Inner wall  22  is positioned sufficiently inward of outer wall  16  (preferably about 2 inches) to provide enough distance for complete absorption without wetness contacting the inward facing side of outer wall  16 . If a cat urinates against a portion of inner wall  22  it will air dry in a short time unlike a conventional litter box where the urine remains suspended in a solid wet clump of pet litter. The wet clump of pet litter does not dry completely and stubbornly adheres to the inward facing surface of outer wall  16 . 
     Pet litter  32  within container  10  may be periodically cleaned by removing hood  12  and pivoting inner wall sections  24  to the folded position. With respect to the second embodiment of FIG. 6, inner wall  22  may be raised clear of outer wall  16  by lifting hood  12  as described above. Moving inner wall  22  as aforesaid facilitates removal of solid waste and clumped pet litter from the end portions of container  10  as shown in FIG.  2 . Since outer wall  16  remains dry, cleaning container  10  is extremely easy. As explained above, inner wall sections  24  may be instantly decoupled from outer wall  16  for convenience to periodically clean and disinfect such parts as necessary. 
     Containers  10  are stackable for display or shipping purposes. In the case of the first embodiment of the invention, inner walls sections  24  are decoupled from outer wall  16  and packed in the interior of container  10  for rapid assembly by the end user. With respect to second embodiment of FIG. 6, the outer wall  16  unit and inner wall units  58  are also stackable as are hoods  12  (FIG.  1 ). 
     As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.