Abstract:
A litter box for an animal, typically a pet, comprises a base which holds a drain pan that contains litter. A drawer slides to and from the interior cavity of the base. The drawer holds a funnel and container, for receiving liquid pet waste from the drain pan. A hinged lid pivots downwardly from the front of the base, to rest on the top of the front end of the drawer where it projects from the front of the litter box. The lid provides a step for pet access to the drain pan.

Description:
[0001]    This application claims benefit of provisional patent application Ser. No. 62/144,933 filed Apr. 9, 2015, the disclosure of which is hereby incorporated by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to devices which are familiarly called litter boxes, that is, to devices for receiving liquid and solid wastes of cats and other small pets. 
         [0003]    Litter boxes provide places where small pets, particularly cats, can urinate and defecate while inside a dwelling. One familiar kind of litter box uses particulates of water absorbent clay such as bentonite, commonly called “cat litter.” Litter boxes require continual maintenance to avoid odors and encourage pet use. The urine causes the litter particles to swell and agglomerate. Solid waste is usually raked from the clumped litter and disposed of in a toilet, outdoors or in a municipal waste stream. While there are commercial litters which are marketed to alleviate the problem of odors, most users find they must often change the litter to avoid unpleasant odors. Cats often like to move the litter about after defecating, and upon repetitive use of a litter box, the cat will be undesirably pawing urine and feces filled litter, providing another incentive to replace the litter. Used litter is commonly disposed of by mixing it with trash or garbage, in that the hydrophilic clay can create a gooey mass if thrown in the yard, it is non-combustible, and it is not suitable for disposal in a sewage system, particularly an onsite treatment system. 
         [0004]    As reflected in commerce and the patent literature, inventors and developers have employed various approaches to improve litter box functioning. In one approach, a non-absorbent particulate is employed as litter and it is placed in a structure having a perforated bottom. The urine flows through the perforated structure and into a collection container. U.S. Pat. No. 6,408,790 of Maguire and U.S. Pat. No. 8,887,667 also Maguire describe such a device. The disclosures of the foregoing patents are hereby incorporated by reference. 
         [0005]    Other factors that influence a consumer&#39;s choice of litter box include convenience of use, ease of cleaning, cost, and “environmental friendliness.” Some inventors have provided litter boxes with trays which pull from beneath the box to ease cleaning. See U.S. Pat. No. 8,683,953 of Ramisch, U.S. Pat. No. 7,380,519 of Ikegami et al., and the Maguire patents. While the manner of making the litter box assemblies is not detailed in most litter box patents, we can reasonably presume from the details of the construction that they are most likely made of molded plastic and, as is well known, molds can be expensive. 
       SUMMARY 
       [0006]    Objects of the invention include providing a litter box device for use by cats and small animals, which device provides ease of use for the pet, ease of cleaning for the owner, ease of disposal of pet waste products, pleasing appearance, and attractiveness to the pet and owner. A further object is to provide a litter box which has low cost of manufacture and which enables economic shipping, that is, which is compact and light in weight when shipped. 
         [0007]    In accord with the invention, an embodiment of litter box for use by an animal, typically a household pet, comprises a base, a drain pan mounted in the base, the pan having a perforated floor for holding particulate litter, and a drawer that slides through a front opening of the base, to and from the interior of the base, beneath the drain pan. The drawer holds a container for receiving liquid from a drain port of the drain pan; preferably, the liquid is channeled to the container by a funnel which is also carried in the drawer. The container and funnel are preferably positioned on a pedestal set within the drawer at a location which is spaced apart from one or both the front and the back of the drawer, to provide storage space for supplies within the drawer. Preferably, the pedestal is a box like structure. When the drawer is open, the funnel may be tilted upon the pedestal, to expose and enable removal for emptying of the liquid waste container. 
         [0008]    When the drawer is fully inserted, i.e., closed, the litter box unit presents a clean and neat appearance. Any odor from the collected liquid waste in the container is minimized because the container has a small opening and is within the mostly closed-off base. Preferably the container is a rectangular cross section common waxed-paper container such are used for retail sale of juice, milk, etc. 
         [0009]    Preferably, the front of the drawer extends beyond the front end of the base when the drawer is closed; and an optional lid that is hinged from the front surface of the base rests on the top of the extending portion of the drawer, thereby to close the front opening of the box, to keep the drawer in place, and to provide a step for the pet to access the litter which is held on the floor of the drain pan. In alternative embodiments, the drawer slides in and out of the base through an opening at the side or back of the base, with or without a lid. 
         [0010]    The base, the drawer, the trays and the pedestal are preferably made of plastic or wax coated cardboard. Preferably the base is made of two pieces of cardboard that are mated. An optional canopy that is above the drain pan is preferably made of three pieces of flexible plastic, for convenient shipment. 
         [0011]    The foregoing and other objects, features and advantages of the present invention will become more apparent from the following description of preferred embodiments and accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is a perspective view of a litter box embodiment of the present invention. The box has a canopy. 
           [0013]      FIG. 2  is a side elevation cross section view of the box in  FIG. 1 . 
           [0014]      FIG. 3  is a partial perspective view of the litter box shown in  FIG. 1 , with the drawer pulled from the base. 
           [0015]      FIG. 4  is an exploded view of a litter box, mostly like that shown in  FIG. 1  and  FIG. 2 . 
           [0016]      FIG. 5  is a perspective view of a drain pan. 
           [0017]      FIG. 5A  is a perspective of an alternative drain pan. 
           [0018]      FIG. 6  is a side cross section view of the pan in  FIG. 5  with addition of a floor for holding litter. 
           [0019]      FIG. 6A  is a side cross section view of an alternative embodiment drain pan having a floor suspended within the pan by means of sides within the drain pan. 
           [0020]      FIG. 7  is partial cutaway perspective view of a container and funnel showing how they set within a pedestal. 
           [0021]      FIG. 7A  is a perspective view of an alternative embodiment funnel. 
           [0022]      FIG. 8  is a perspective view of a floor for a drain pan. 
           [0023]      FIG. 9  is a perspective view of another embodiment of litter box of the present invention. 
       
    
    
     DESCRIPTION 
       [0024]    Certain parts of the present invention described below are preferably made of corrugated boxboard, a paperboard product of the kind familiarly used for shipping containers, which also referred to more generally as cardboard box material. Using cardboard as a material of construction provides an economic and environmentally friendly litter box. Preferably, the cardboard is treated with hot wax or a like substance to impart water resistance. In one process, often referred to as cascading, the interior is coated; such process is familiar in its use with cardboard shipping boxes for seafood and vegetables. In another process, often referred to as curtain-coating, the exterior of the cardboard structure is coated with a plastic material, usually clear. Optionally, the cardboard is waxed with a neutral or a cat-attractive scent coating. The exterior surfaces of the cardboard structures may be decoratively printed or painted. The parts described as being made of cardboard may be formed by alternative means, including by molding, welding, and/or adhesively attaching plastic materials. 
         [0025]    An embodiment of litter box  20  of the present invention is shown in the perspective view of  FIG. 1 , a somewhat simplified cross section of  FIG. 2 , and in the perspective part-view of  FIG. 3 . The box  20  is shown in exploded fashion in  FIG. 4 . 
         [0026]    The box  20  comprises base  22  which holds drain pan  26  within which is perforated sheet floor  28 . In an embodiment of the present invention, the drain pan may be about 55 cm long, 44 cm wide and 8.5 cm deep. The other elements of the box will be proportioned to the drain pan. Non-water absorbing litter (not shown) is placed on the surface of floor  28  when the box is put into use, to attract the cat or other pet to use it for defecating and urinating. The feces are caught amongst the litter and the liquid pet waste (urine) flows through the floor to the bottom of the pan  26 , then through opening  40  in the pan  26  to funnel  36 ; then into a receptacle/container  34  which is held in a drawer  30 . 
         [0027]    The base of a litter box of the present invention preferably has walls at the front, back and sides, the exteriors of which are a substantially vertical; within the generality of such invention, exteriors may have modest inclines and curves. 
         [0028]    Box  20  has an optional enclosure, namely canopy  24  which is preferably clear flexible plastic; the canopy provides an element of security and privacy (when decorated or not-clear) and helps to avoid scattering of litter. In  FIG. 1 , the canopy is shown as one piece. In  FIG. 4 , as discussed below, it is shown in multi-piece configuration. 
         [0029]    As shown particularly in  FIG. 4 , box  20  comprises a base  22  which is preferably made of two mated pieces of cardboard  22 A,  22 B, as shown in  FIG. 4 . The pieces  22 A,  22 B may be glued, stapled, or otherwise attached to one another to form the base  22 . In alternate embodiments the base may be one piece. In still other embodiments, when the box  20  is large, integral strengthening ribs may be formed as part of the cardboard base (as well as other cardboard parts). 
         [0030]    Drawer  30  is slidable in and out of an opening at the front of the base from a pulled out position to a fully inserted position, also called the home position. There is a portion of base above the opening through which the drawer moves. The drawer also is preferably made of cardboard. In the embodiment of box  20  shown in  FIG. 1  and  FIG. 2 , when the drawer is in the home position (also referred to as the drawer-closed situation) a portion of the drawer extends from the front face of the base so that the front of the box presents a stepped shape. The drawer in  FIG. 2  is in the home position. The drawer in  FIG. 3  is in fully pulled out position. When the drawer is in pulled out position functionally, a user can access and remove the container from the drawer. 
         [0031]    Lid  32  is hinged from the front of the base, to rest on the front edge of drawer  30  when the drawer is in its home position. See  FIG. 1  and  FIG. 2 . When the lid is hinged-down and closed, the top surface of lid  32  provides a step surface that is intermediate in elevation between the top of the base and the bottom of the base (which in use normally sets on a dwelling floor or other support surface) thereby easing animal access to the litter in the drain pan. Lid  32  preferably has a lip  31  which captures the outer end of the drawer to keep it in the home position. Alternatively, there is no lip  31 . The hinge for the lid may be of the so-called living hinge type, essentially integral with the front wall of the base; other known kinds of hinges may be used. 
         [0032]    In a variation from what is shown in  FIG. 1  and  FIG. 2 , the drawer and lid may be configured so that when the lid is at rest on the front end of the drawer the lid surface is sloping downwardly from the hinge point. Optionally, the lid may have a roughened or grit-containing coating to provide gripping surface for animal paws and to inhibit scattering further such litter as the animal inadvertently ejects from floor/drain pan during use of the litter box. 
         [0033]    In another alternative embodiment of the invention, not shown but easily conceived, the front of drawer  30  in the home position is flush with the front surface of the base that is above the drawer opening, and there is no lid and step. In still other alternative embodiments, the drawer—with or without extension beyond the adjacent vertical wall of the base—may slide in and out through an opening which is at a side or at the rear of the base  22 , instead of at the front as shown. 
         [0034]    Pedestal  38  is at a mid-length location of the drawer  26 . Pedestal  38  is box-like and has a top shaped as a rectangular tray having a cutout. Preferred pedestal  38  is configured to hold funnel  36  and laterally to restrain container  34 . Pedestal  38  preferably has a rectangular opening  58  at its top, within which is received and suitably located container  34 , relative to the drawer and to the funnel, or relative to the drain port of the drain pan in an embodiment which does not employ a funnel. 
         [0035]      FIG. 7  is a partial cutaway view of pedestal  38 , showing how funnel  36  mounts on pedestal. The preferred funnel has opposing side legs  50 , the tab-ends  51  of which slip into slots of the pedestal top. To remove the container, the funnel may be tilted in the direction transverse to the front-back direction of the drawer with the legs in the slots, or the funnel may be removed by lifting vertically. 
         [0036]    The function of the funnel is to make less critical the alignment of the spout  56  of container  34  with the discharge port  40  of the drain pan. The funnel has a conical interior portion  52  which channels liquid received from the drain pan to output port  54 . Port  54  is fitted into the spout  56  of container  34 . 
         [0037]    The funnel may be mounted on the pedestal by other means than by the aforementioned tabs. For instance, as shown in  FIG. 7A , funnel  136  with port  154  has opposing side stepped legs  150 , the bottommost tabs  151  of which engage the fore-aft sides of the pedestal. Tabs  151  enable tilting of the funnel or removal of the funnel from the pedestal. In still another alternative, the funnel may be clamped or screwed to the pedestal. 
         [0038]    In another embodiment of funnel, the structure which comprises the funnel legs may be a separate structure from the cone of the funnel itself; or uprights integral with the pedestal may project upwardly to provide supporting structure for holding the funnel in substitution of legs. 
         [0039]    Fore and aft of the pedestal within the drawer are optional trays  42 ,  44 , shown only in  FIG. 4 . The trays  42 ,  44  fit in spaces which are fore and aft of the pedestal. See the spaces in  FIG. 2 . The pedestal and trays are preferably made of cardboard, preferably as described above. 
         [0040]    The space in the drawer which is fore and aft of the pedestal—whether trays are used or not—may be used for storage of replacement litter or supplies associated with cat care. When present, the trays are shaped so that they locate the pedestal and funnel along the front-back length of the drawer. When the drawer is in its home position, the funnel is beneath the drain port of the drain pan. In embodiments of the litter box of the present invention, when there are no trays, pedestal  38  may be held in position within the drawer by means such as struts or brackets, cooperating engagement features of the drawer and pedestal, and such as clips, tabs, bands, staples, etc. 
         [0041]    Container  34  is preferably a commercial wax-board juice container, such as is used for products sold in retail stores. Funnel  36  mounts on the pedestal  38  and channels liquids into the container  34 . The relatively small spout and associated opening that characterizes the aforementioned kind of commercial juice container, as illustrated, means that there will be limited evaporation and resultant odor from collected liquid waste (urine), compared to having an open container, or compared to the urine being only collected in the bottom of the drain pan  26 . In the generality of the invention, the container is rectangular or round or non-round in cross section and has an opening which is disposed for liquid flow communication with the port of the drain pan when the drawer is in the home position. Optionally, the container may be fitted with a liquid level sensor or a weight sensor, so the owner is signaled when it is time to empty the container. 
         [0042]    The apparatus configuration enables the funnel may be easily cleaned when needed and enables the container to be conveniently removed and replaced. Referring again to  FIG. 1-4 , when the drawer is pulled from the base sufficiently to expose the funnel  36  and container  34 , the funnel may be tilted in a direction which is transverse to the length of the drawer to slide the legs upwardly from the slots in the pedestal, or the funnel may be simply lifted vertically. Next, container  34  may be removed from its nested place within the pedestal and taken away to be emptied. Alternatively, when feasible, the container may be disposed of with its contents and replaced with a new container. Optionally, the pedestal and/or container may be fitted with handles or straps for ease of removal and handling. 
         [0043]    An advantage of the present invention is that the container can be one that is recycled from its use as juice packaging, lowering the user&#39;s cost. In alternative embodiments of the invention, a container (other than the aforementioned recycled juice container) having an attached or integral funnel may be employed. In a still further alternative embodiment, the funnel may be omitted and the container may be provided with an opening sufficiently sized to receive liquid from the port of the drain pan without spillage, notwithstanding there is some disadvantage in that a larger opening can let odors and vapors escape from the container more than occurs with the preferred embodiment container. 
         [0044]    While the above-described configuration of pedestal  38  is preferred, other embodiments of pedestal may be used: the term pedestal in the claims herein shall comprehend any structure configured for holding in place a container within the drawer, optionally with a funnel mounted above the container. For example, the container may be restrained from fore-aft and sideways movement by ridges or cleats on the bottom of the drawer. For example, the container may be held in place by detachable elastic bands or detachable light clamps. For example, the funnel could be restrained from movement by its engagement with the restrained container rather than both elements being separately engaged with the pedestal. 
         [0045]      FIG. 5  is a perspective view of an embodiment of drain pan  26 , showing how the pan bottom comprises lands  46 ,  44  and a drain port  40 .  FIG. 6  is a cross section of drain pan  26 . The bottom of the pan is preferably sloped slightly when the drain pan sets within the opening of the base, so that liquid flows toward the port  40 . 
         [0046]      FIG. 6  shows the addition of a flat perforated floor panel  28  which is supported by the top surfaces of the lands  44 ,  46 . A floor panel is optional, but preferred. The floor panel holds the litter, better allowing liquid waste to flow to the drain port  40 . An advantage of the configuration of drain pan  26  is that it has ease of cleaning. Alternative features for supporting the floor panel and providing drainage to the drain port  40  may be used. In an alternative embodiment of the invention, the floor panel may have other configurations, including that it may have downwardly-projecting ribs or pins for supporting the panel on a flat floor of a drain pan. In a still further alternative, small separate spacer blocks may be used. 
         [0047]      FIG. 8  is a perspective view of floor panel  28 . In an embodiment of dimensioned box  20  as noted above, drain pan  26  may be about 55 cm length, 44 cm wide, and about 8.5 cm deep. For such a pan, floor panel  20  may be about 38 cm long and 28 cm wide. A floor panel may have a circumscribing upward-running outer rail (not shown) or other shaping, to give the floor panel a generally concave shape for better retaining litter, particularly when the panel is lifted from the drain pan to discard the litter. See the description below about  FIG. 6A   
         [0048]    A floor panel may be made of polyethylene, other water resistant plastic, or other material of about 3 mm thick and may have a multiplicity of through-holes  48  which are round or some other shape. The holes  48  have dimensions that are small enough to prevent through-passage of the particles of litter, the use of which is anticipated. In one embodiment of floor panel, round holes are about 2 mm in diameter and spaced apart 4 mm center to center. Less preferably, the floor panel is a solid sheet with space around the edges for down-flow of liquid animal waste. 
         [0049]      FIG. 5A  shows an alternative embodiment of molded plastic drain pan  126  having a plurality of peninsular-shape lands  146  around the periphery of the interior of the bottom of the pan, and a center island  144 . 
         [0050]      FIG. 6A  is a cross section like  FIG. 6 , showing another alternative embodiment drain pan  26 A with a suspended floor. Floor  28 A is concave in shape; there is a perforated bottom which is suspended above the interior surface of the bottom of drain pan  26 A by means of at least two opposing side webs  58  that rise up from the substantially flat bottom surface, with lips which rest on the upper edges of the drain pan periphery. There is a space under the floor which allows liquid which flows through the floor panel to run across the bottom of the drain pan to drain port  40 A. Preferably, there are four side webs  58 , in which case the floor might be characterized as being basket shape. Floor panel  28 A may be made of perforated plastic sheet as previously described, or it may be made of a corrosion resisting metal mesh. In still another embodiment of the invention, not shown, the floor rests directly on the bottom of the drain pan and there is either sufficient uneven fit, or texturing of the floor or of the bottom of the drain pan, to enable liquid flow between the underside of the floor and the bottom interior surface of the drain pan. 
         [0051]    The optional enclosure which is canopy  24  may be made of a single piece of arch shape material as shown in  FIGS. 1, 2, and 4 . In one embodiment the sheet material is flexible enough to be shipped as a flat sheet and bent into an arch by the user at the time of assembly of the litter box  20 , as pictured in  FIG. 1  and  FIG. 2 . The opposing side edges of canopy  24  slip into slots in the top of base  22 , adjacent the opposing side lengthwise lips of the drain pan  26 . 
         [0052]    In an alternative embodiment illustrated in  FIG. 4 , for more compact and economic shipment, the canopy  24 A is comprised of three flat flexible panels, top panel  25 A, and two side panels  25 B, which are connected to each other. Preferably, the three panels are nominally the same overall length and shipped flat for efficient packaging in knock-down condition; they are then bent by the user at the time of installation. Alternatively the three panels may be shipped with a preformed curve shape. 
         [0053]    Referring to  FIG. 4 , canopy  24  comprises two like opposing side panels  25 B and top panel  25 A, shown in curved condition. Top panel  25 A forms an overlap joint with each side panel  25 B. Two mating cleats  42  are preferably screwed to each other and sandwich the overlap joint portions between each side panel  25 B and the top panel  25 A. The lower ends of side panels  24 B optionally are screwed or otherwise attached to the upper sides of the base, or slip into lengthwise slots in the top of the base, or are shaped in the form of a multiplicity of downwardly extending tabs that are received in spaced apart lengthwise slots in the top of the base. 
         [0054]    In another variation, the canopy  24 ,  24 A enclosure above the drain pan may comprise an additional panel, not shown, which closes off the back opening of arch shape curve structure. In a still further variation, the enclosure may be fence-like with an open top, embodied by enclosure  124  in  FIG. 9 . In  FIG. 9  litter box  120  is comprised of base  122 , drawer  130 , drawer lid  132  and drain pan  126 . Fence enclosure  124  fits into collar  125  which is an upward extension of the rim of the drain pan  126  or a separate like-structure. Fence  124  has a substantially vertical back and two substantially vertical sides, and a front opening for animal access. 
         [0055]    With reference to  FIG. 9 , and applicable to other embodiments. An inclined ramp, not shown, may run from vicinity of the opening in the enclosure  124 , or the edge of drain pan  126  when there is no enclosure, to the floor that lies outboard of the front of drawer  130 , to enable infirm pets more easily to access the drain pan. The ramp could either rest lightly on the outer edge of lid  132 , or be slightly spaced apart from it. 
         [0056]    Different litters may be used with the invention. A preferred litter that is resistant to urine absorption comprises safflower seeds. If the user wishes, litter which is hydrophilic may be used, it being known that various litters only imperfectly absorb urine. 
         [0057]    The invention, with explicit and implicit variations and advantages, has been described and illustrated with respect to several embodiments. Those embodiments should be considered illustrative and not restrictive. Any use of words which relate to the orientation of an article pictured in space is for facilitating comprehension and should not be limiting should an article be oriented differently. Any use of words such as “preferred” and variations thereof suggest a feature or combination which is desirable but which is not necessarily mandatory. Thus embodiments lacking any such preferred feature or combination may be within the scope of the claims which follow. Persons skilled in the art may make various changes in form and detail of the invention embodiments which are described, without departing from the spirit and scope of the claimed invention.