Patent Publication Number: US-2005115509-A1

Title: Litter box

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      Not Applicable  
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH  
      Not Applicable  
     REFERENCE TO MICROFICHE APPENDIX  
      Not Applicable  
     FIELD OF THE INVENTION  
      The present invention generally relates to an improved litter box and, more particularly, to a litter box having relatively high sidewalls to better retain litter and the like within the litter box.  
     BACKGROUND OF THE INVENTION  
      A cat instinctively seeks to bury its excrement by digging and scratching litter or whatever else is present. At times this digging and scratching can be quite vigorous. As a result, litter is frequently thrown out of conventional litter boxes. Additionally, male cats are known to spray urine out of conventional litter boxes. Many attempts have been made to design a litter box from which no litter, feces, or urine escapes. For example see U.S. Pat. Nos. 3,310,031, 5,590,623, D370,094, D370,095, and D392,076 the disclosures of which are each expressly incorporated herein in their entirety by reference.  
      U.S. Pat. No. 3,310,031 discloses a “Sanitary Cat Box” which includes a material retaining structure that substantially extends the height of the end walls of the litter box but not the sidewalls of the litter box. As a result, the sidewalls do not adequately retain litter, feces, and urine within the litter box. Additionally, an interface between the material retaining structure and the litter box can form a trap, particularly for urine, which not only can require more frequent cleaning of the litter box but also makes cleaning of the litter box more difficult and unsanitary.  
      U.S. Pat. No. 5,590,623 discloses a “Cat Litter Box” which has no side openings and no doors or flaps to admit cats. This litter box requires cats to enter through the top of the litter box using their natural jumping ability. An attempt is made to make sidewalls of the box tall enough to prevent the escape of litter yet low enough to permit entry by a cat over the sidewalls. This compromise in height, however, can permit the escape of litter, feces, or urine in some cases, such as with a vigorous scratcher or very large cats, and can prevent the entry of the cat into the litter box in other cases, such as with injured, handicapped, or extremely old cats. Additionally, this litter box is formed of separate upper and lower sections which are secured together. As noted above, this interface between the separate sections can form a trap, particularly for urine, which not only can require more frequent cleaning of the litter box but also makes cleaning of the litter box more difficult and unsanitary  
      U.S. Pat. Nos. 3,310,031, 5,590,623, D370,094, D370,095, and D392,076 each disclose a “Cat Litter Box” having a removable lid which closes the top of the litter box. While such lids prevent entry of cats through the top opening of the litter box, these lids reduce and/or eliminate ventilation of the litter box. Without adequate ventilation, finicky cats can quickly refuse to use the litter box resulting in more frequent cleaning of the litter box. Additionally, as noted above, the interface between the lid and the litter box can form a trap, particularly for urine, which not only can require more frequent cleaning of the litter box but also makes cleaning of the litter box more difficult and unsanitary.  
      While many attempts have been made to design litter boxes from which no litter, feces, or urine escapes, applicant is not aware of any litter box which does not have at least one of the above-noted problems or limitations. Accordingly, there remains need in the art for an improved litter box.  
     SUMMARY OF THE INVENTION  
      The present invention provides a litter box which overcomes at least some of the above-noted problems of the related art. According to the present invention, a one-piece litter box for an animal comprises, in combination, a container having a base wall with sidewalls extending vertically upward from edges of the base wall to form a hollow interior space. A top opening is formed by upper edges of the sidewalls and an entrance opening is formed in one of the sidewalls. The entrance opening is free of coverings so that the animal can see through the entrance opening. The sidewalls form a height of the container which substantially prevents the animal from seeing over the sidewalls while standing within the hollow interior space so that the animal faces the entrance opening while within the hollow interior space.  
      According to yet another aspect of the present invention, a one-piece litter box comprises, in combination, a container having a base wall with sidewalls extending vertically upward from edges of the base wall to form a hollow interior space. A top opening is formed by upper edges of the sidewalls and an entrance opening is formed in one of the sidewalls. The sidewalls form a height of the container which is at least fifteen inches while the entrance opening is spaced at least six inches above the bottom wall of the container. The entrance opening is circular and has a diameter in the range of about eight inches to about ten inches.  
      From the foregoing disclosure and the following more detailed description of various preferred embodiments it will be apparent to those skilled in the art that the present invention provides a significant advance in the technology of litter boxes. Particularly significant in this regard is the potential the invention affords for providing a high quality, reliable, inexpensive, and easily cleaned product. Additional features and advantages of various preferred embodiments will be better understood in view of the detailed description provided below.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      These and further features of the present invention will be apparent with reference to the following description and drawings, wherein:  
       FIG. 1  is a perspective view of a litter box according to a preferred embodiment of the present invention;  
       FIG. 2  is a front elevational view of the litter box of  FIG. 1 ;  
       FIG. 3  is a cross-sectional view taken along line  3 - 3  of  FIG. 2 ; and  
       FIG. 4  is a top plan view of the litter box of FIGS.  1  to  3 . 
    
    
      It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention. The specific design features of the litter box as disclosed herein, including, for example, specific dimensions, orientations, and shapes of the various components will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration. All references to direction and position, unless otherwise indicated, refer to the orientation of the litter box illustrated in the drawings. In general, up or upward refers to an upward direction within the plane of the paper in  FIG. 2  and down or downward refers to a downward direction within the plane of the paper in  FIG. 2 .  
     DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS  
      It will be apparent to those skilled in the art, that is, to those who have knowledge or experience in this area of technology, that many uses and design variations are possible for the improved litter box disclosed herein. The following detailed discussion of various alternative and preferred embodiments will illustrate the general principles of the invention with reference to a litter box for use with domestic felines or cats. Other embodiments suitable for other applications, such as litter boxes for other animals such as rabbits, ferrets, or other household pets, will be apparent to those skilled in the art given the benefit of this disclosure.  
      Referring now to the drawings, FIGS.  1  to  4  show a litter box  10  according to a preferred embodiment of the present invention. The illustrated litter box  10  is in the form of a unitary or one-piece box or container  12  having a bottom or base wall  14  and sidewalls  16 ,  18 ,  20 ,  22  upwardly extending from peripheral edges of the base wall  14  to form a hollow interior space  24 . The term unitary and one-piece is used within the specification and claims to mean a single piece or component of continuous material formed such as, for example, by molding. The width of each of the sidewalls  16 ,  18 ,  20 ,  22  is sufficiently sized so that the hollow interior space  24  can hold a cat. The width of each sidewall  16 ,  18 ,  20 ,  22  is preferably at least about ten inches and more preferably at least about fourteen inches. The height of each of the sidewalls  16 ,  18 ,  20 ,  22  is sufficiently sized so that the spraying of urine or the escape of litter or feces over the sidewalls  16 ,  18 ,  20 ,  22  is avoided, that is, the height is preferably at least eye level to an average cat and more preferably taller than the height of an average cat. Accordingly, each of the sidewalls  16 ,  18 ,  20 ,  22  preferably have a height of at least about fifteen inches, more preferably a height of at least about eighteen inches, and even more preferably a height of at least about twenty inches. The illustrated base wall  14  is rectangular-shaped but other suitable shapes such as, for example, a square, triangle, pentagon, hexagon, or the like can be utilized within the scope of the present invention. This interface between the base wall  14  and the sidewalls  16 ,  18 ,  20 ,  22  are preferably rounded to ease cleaning of the container  12 . The interface preferably has a radius of at least about one-half inch and more preferably a radius of at least about three-quarters of an inch. The interface between adjacent ones of the sidewalls  16 ,  18 ,  20 ,  22  is also preferably rounded to ease cleaning of the container  12 . This interface preferably has a radius of at least about one inch and more preferably a radius of at least about two inches.  
      As best shown in  FIG. 3 , the base wall  14  and the sidewalls  16 ,  18 ,  20 ,  22  of the illustrated container  12  are seamless so that the interior surface  26  of the container  12  is smooth and continuous (other than a single opening as described in more detail hereinafter). This smooth and continuous interior surface  26  is free of sharp corners, channels, cracks, seams, and other traps which can hold litter, feces, and urine. Therefore, not only is cleanup easier, but urine is not trapped away from the absorbent litter  28  which can cause odor and unsanitary conditions which result in the need for more frequent cleaning. The smooth and continuous interior surface  26  also enables the container  12  to be easily used and cleaned without liners which themselves can be urine traps. While it is preferred that the litter box  10  is used without liners, it is noted that alternatively the litter box  10  can be used with liners but some of the advantages of the present invention may not be fully appreciated. When using a liner, the liner can be relatively short, that is located entirely below the entrance opening  36  and secured to the sidewalls in a suitable manner such as, for example, tape. Alternatively, the liner can be relatively tall so that it extends to and is secured about the lip  30 . It is believed that suitably sized off-the-shelf kitchen trash bags are available which can adequately serve this purpose. When using these tall liners, it is necessary to cut a suitable opening which is located at the entrance opening  36  and it may be desirable to tape or otherwise secure the liner at the edge of the entrance opening  36 .  
      Upper edges of the sidewalls  16 ,  18 ,  20 ,  22  form a lip  30  defining a top opening  32  for the container  12  to stiffen the sidewalls  16 ,  18 ,  20 ,  22 . The illustrated lip  30  is in the form of an inverted-j so that the lip  30  extends outwardly and downwardly from the upper edge of the sidewalls  16 ,  18 ,  20 ,  22 . The lip  30  preferably forms a rounded upward-facing surface  34  and preferably has a width which is sufficiently narrow to prevent, or at least discourage, cats from standing thereon which could tip or overturn the litter box  10 . The lip  30  preferably has a width of no more than one-half inch. The top opening  32  is preferably entirely open and free of any covers, screens, lids, shields, or the like to avoid urine traps, provide ventilation, and ease clean-up.  
      One of the sidewalls  16  is provided with an entrance opening  36  of suitable size and shaped for ingress and egress of a cat therethrough but no larger than necessary so that the spraying of urine or the escape of litter or feces therethrough is avoided or at least minimized. The entrance opening  36  is preferably circular or at least having a rounded lower edge to minimize the size of the entrance opening  36  near its lower end. The entrance opening  36  is preferably in the shape of a circle having a diameter in the range of about eight to about ten inches, and more preferably having a diameter of about nine inches. The lower end of the entrance opening  36  is preferably spaced above the base wall  14  an adequate distance which easily permits the passage of cats through the entrance opening  36  but is spaced above the litter  28  an adequate distance so that the spraying of urine or the escape of litter or feces through the entrance opening  36  is avoided or at least minimized. It has been determined that a spacing of about six inches is optimal for use of litter  28  having a depth of about three inches. Thus, the entrance opening  36  is preferably located above at least forty percent of the height of the sidewall  16 . The entrance opening  36  of the illustrated rectangular container  12  is located in one of the sidewalls  16 ,  18  of longer length, but it is noted that the entrance opening  36  can alternatively be located in one of the sidewalls  20 ,  22  of shorter width, particularly where the container  12  has relatively small dimensions so that the cat freely faces the entrance opening  36  when within the container  12 . The entrance opening  36  is preferably centered on the sidewall  16  so that the cat can easily look out of the entrance opening  36  from within the container  12 .  
      The entrance opening  36  is preferably the only opening in the sidewalls  16 ,  18 ,  20 ,  22 , that is, the sidewalls  16 ,  18 ,  20 ,  22  are preferably smooth and continuous except for the single opening  36 . Also, the entrance opening  36  is preferably free of doors, shields, covers and the like which can be urine traps and complicate cleaning of the litter box  10 . It has been determined that when the sidewalls  16 ,  18 ,  20 ,  22  are tall enough to obscure the view of the cat, most cats will turn to face the entrance opening  36  while within the container  12  so that they can see out of the container  12 . With the cat facing the entrance opening  36  and the remaining sidewalls  18 ,  20 ,  22  being free of any openings, the spraying of urine or the escape of litter or feces through the entrance opening  36  is substantially avoided even though the entrance opening  36  is located in one of the sidewalls  16 ,  18 ,  20 ,  22 . Note that a cat typically does not spray urine or scratch litter forward toward it head.  
      The container  12  can be formed of any suitable material and in any suitable manner. The container  12  is preferably molded of a suitable plastic material. The entrance opening  36  can be molded in place or formed by cutting after the container  12  is molded. The container material is preferably an opaque material so that the cat cannot see through the sidewalls  16 ,  18 ,  20 ,  22  and must face the entrance opening  36  to see out of the container  12 . The container  12  can be advantageously include antibacterial or antimicrobial material such as, for example, MICROBAN so that the litter box has additional sanitary protection.  
      The illustrated embodiment of the litter box  10  can be produced from an off-the-shelf base container such as a seven-gallon plastic wastebasket having a length of about fourteen and one-half inches, a width of about ten and one-half inches, and a height of about fifteen inches which is available from Universal Office Products, Inc. Another suitable base container is believed to be an eighteen gallon plastic storage tote having a length of twenty-four inches, a width of about seventeen inches, and a height of about fifteen inches which is available from Sterilite Corporation. It is noted that these base containers are provided as examples only and that many other containers meet the desired features discussed in detail hereinabove.  
      To use the litter box  10 , a layer of the litter or other suitable absorbent material  28  is preferably placed in the bottom of the container  12  directly on the base wall  14 . The layer of litter  28  preferably has a depth of about three inches. A cat enters the litter box  10  through the entrance opening  36 . A cat will typically not enter through the top opening  32  because the sidewalls  16 ,  18 ,  20 ,  22  do not enable the cat to see in and the lip  30  is not wide enough to support the cat. Once inside the container  12 , the cat naturally turns to face the entrance opening  36  so that it can see out of the container  12  since it cannot see over the sidewalls  16 ,  18 ,  20 ,  22 . Upon relieving itself and scratching and digging the litter  28 , any flying litter, feces, and urine contacts the continuous sidewalls  18 ,  20 ,  22  and remains within the container  12  as the cat faces the entrance opening  36 . The cat then exits the entrance opening  36 . When the litter box  10  is to be cleaned, any contents are simply poured into a trash bag or the like and the interior of the container  12  is flushed with water and/or other cleaning solution and is easily wiped clean. The litter box  10  is then clean and ready for reuse.  
      It is apparent from the above detailed description that the relatively tall sidewalls and the shape, size, and location of the entrance opening avoids litter, feces, and urine from being ejected from the litter box. It is also apparent that, the invention is relatively inexpensive to manufacture, is lightweight, reduces maintenance and labor, and can be easily cleaned by scooping clumped litter through the top opening. Because it is lightweight, the litter box can be easily tipped and emptied by tilting and pouring the litter out of the container. It is additionally apparent, that the one-piece design of the litter box eliminates the need for assembly and any urine traps produced by prior multi-component designs.  
      From the foregoing disclosure and detailed description of certain preferred embodiments, it will be apparent that various modifications, additions and other alternative embodiments are possible without departing from the true scope and spirit of the present invention. The embodiments discussed were chosen and described to provide the best illustration of the principles of the present invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the present invention as determined by the appended claims when interpreted in accordance with the benefit to which they are fairly, legally, and equitably entitled.