Abstract:
An improved sanitary facility for pets for the collecting, removing and disposing of small animal excrement without the attendant mess and odor heretofore experienced, uses a rotatable chamber which contains pet litter, sand or other suitable material. A first opening is provided for animal ingress and egress, and a second opening for expulsion of separated waste. Filter means, disposed circumferentially within the chamber, selectively separate solid excrement and agglomerated matter from unsoiled litter as the chamber is rotated. The separated waste is urged, by the action of gravity on the inclined filter means, toward a sealable second opening in the chamber. The separated matter is expelled from the chamber through the second opening and deposited in an attached receptacle. The media&#39;s weight prevents rotation of the chamber during use by the animal. Means are also provided for automatically sealing the second opening to prevent odor from escaping the chamber.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a non-provisional application describing the same invention as a currently active provisional application Ser. No. 60/832,859, filed on Jul. 24, 2006, and the present non-provisional hereby claiming date priority therefrom. 
     
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable. 
         [0003]    The Names of the Parties to a Joint Research Agreement 
         [0004]    Not applicable. 
       INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTTED ON A COMPACT DISC 
       [0005]    Not applicable. 
       REFERENCE TO A “MICROFICHE APPENDIX” 
       [0006]    Not applicable. 
       BACKGROUND OF THE INVENTION 
       [0007]    1. Field of the Present Disclosure 
         [0008]    This disclosure relates generally to animal litter boxes and more particularly to the type of litter box that is rotated for segregating waste materials from clean litter. 
         [0009]    2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98 
         [0010]    Carter, U.S. Pat. No. 4,120,264, discloses an improved sanitary facility for pets for the collecting, removing and disposing of small animal excrement without the attendant mess and odor heretofore experienced. A rotatable chamber which contains pet litter, sand or other suitable material has a first closeable opening for animal ingress and egress, and a second opening for expulsion of separated waste. Filter means, disposed circumferentially within the chamber, selectively separate solid excrement and agglomerated matter from unsoiled litter as the chamber is rotated. The separated waste is continuously urged, by the combined action of gravity and the incline of the filter means, toward a second sealable opening in the chamber. The separated matter is expelled from the chamber through the second opening and deposited in an appropriate receptacle. Means are provided to prevent rotation of the chamber during use by the animal. Means are also provided for automatically sealing the second opening to prevent odor from escaping the chamber. 
         [0011]    Pierson, Jr., U.S. Pat. No. 4,846,104, discloses an apparatus for mechanical separation of cat solid waste, randomly buried in cat litter, and cat urine saturated litter clump waste from surrounding clean cat litter and mechanically removing the waste to storage, the apparatus including: a support including a waste collection region; a circular housing that is rotatably mounted about its axis on the support over the waste collection region, the housing having an opening in its periphery for passage of a cat when in a first rotational position and for passage of the solid waste and litter clump waste when in a second, downwardly directed, rotational position over the waste storage region; a solid partition extending inwardly from the periphery at a location adjacent to the opening so as to trap litter on the side opposite of the solid partition from the opening when the opening is in the second rotational position; a screen that retains the solid waste and litter clump waste, the screen extending inwardly from the periphery at a location spaced from the solid partition so as to pass through the litter as the housing is rotated in a manner that causes the opening to move from the first rotational position to the second rotational position, whereby when the housing rotates through a complete revolution, the solid waste and litter clumps are automatically discharged through the opening into the waste collection region, the litter is automatically sifted and aerated by passing twice through the screen, and the litter is retained in the housing. 
         [0012]    Shirley, U.S. Pat. No. 5,048,464, discloses a litter system that includes a chamber for containing a quantity of particulate litter. The chamber includes front and rear walls, the front wall thereof including an aperture providing an entry way to the chamber for an animal. A helical shaped screen is disposed within the chamber and extends from adjacent the front end to adjacent the rear end of the chamber for separating the litter from animal waste and for transporting the animal waste through the chamber. Structure is provided for rotating the chamber, such that animal waste is transported through the chamber as the chamber rotates. 
         [0013]    LaRoche, U.S. Pat. No. 5,107,797, discloses a litter box that includes a rotatable enclosure having at least one access opening for a domestic animal and a rake disposed on its inner surface, a motor for selectably rotating the enclosure, and a receptacle disposed within the enclosure and movable between a first position generally against the inner surface of the enclosure, and a second position which is nearly vertically disposed within the enclosure. In operation, the receptacle is extended to an operative position, and the enclosure is rotated so that the rake will separate relatively large particles of solid excrement from the litter for deposit into the receptacle. The receptacle is then retracted to its initial, rest position. The litter box may further operate to detect the presence of a domestic animal within the enclosure, and to initiate rotation of the enclosure when the domestic animal leaves the enclosure, to provide for fully automated operation of the litter box. 
         [0014]    Hoeschen, U.S. Pat. No. 5,509,379, discloses an animal litter box for automatically separating waste materials from animal litter. A rotating cylinder is provided with an internal surface for receiving the animal litter and waste materials. A perforated surface has one end fixed to the internal surface of the rotating cylinder so that as the cylinder is rotated, the animal litter and waste materials fall onto the perforated surface. The perforated surface includes openings sized to permit the animal litter to fall through the perforated surface and sized to capture the waste materials upon the perforated surface. A collection assembly is coupled to the perforated surface so that as the rotating cylinder continues to rotate, the waste materials supported on the perforated surface are guided to the collection assembly and are thereafter conducted to a waste reservoir. After the rotating cylinder has been rotated 360 degrees, the waste has been separated from the animal litter and is stored in the reservoir with the animal litter ready to receive new kitty urine and solid waste materials. 
         [0015]    Flores, U.S. Pat. No. 5,551,375, discloses a pet waste box for collecting waste deposited by a pet, and for subsequent removal and disposal of the pet waste. The waste box comprises a housing including opposed first and second sidewalls, opposed front and back walls, and opposed top and bottom walls, an interior space defined by the walls for retaining pet litter and pet waste, a first opening through which a pet may enter and exit the housing, a second opening, and a structure for supporting the housing for rotation about a horizontal axis. The housing also includes a structure for closing the first opening, and a removable drawer received through the second opening and having a waste separation screen and a waste retaining partition. The screen and the partition are positioned within the housing so that, as the housing is rotated through one revolution, the screen separates the waste from the litter, and the waste is retained between the partition and the screen. The waste is then disposed by removing the drawer from the housing, and emptying the waste into an appropriate receptacle. 
         [0016]    Page, U.S. Pat. No. 5,752,465, discloses an animal litter device that includes a chamber that is rotatable about a generally horizontal axis, the chamber having a first-rotation position and a second-rotation position. An internal portion of the chamber is disposed at a bottom of the chamber when the chamber is in the its first rotation position whereat the chamber is usable by an animal, and this internal portion of the chamber is disposed generally at a top of the chamber when the chamber is in its second rotation position whereat the chamber is not usable by an animal. A dump opening is located at a second portion of the chamber, the dump opening being located at or near a top of the chamber when the chamber is in its first-rotation position, and being located at a bottom of the chamber when the chamber is in its second-rotatable position. A moisture impervious, flexible and weighted liner has boarder portions thereof fixed to the interior of the chamber, and has a weighted mid-portion covering the internal portion of the chamber and movable relative thereto. A mass of litter loosely sits on the flexible liner when the chamber is in its first rotation position. Waste separation means within the chamber operates when the chamber is rotated in a first direction between its first-rotatable position and its second-rotatable position to separate animal waste from the mass of litter, whereupon the separated animal waste exits the chamber by way of the waste opening. When the chamber is rotated in a second direction between its first-rotatable position and its second-rotatable position, the mass of litter to exits the chamber by way of the exit opening. 
         [0017]    Emery, U.S. Pat. No. 6,234,112, discloses a self-cleaning pet litter box assembly that automatically separates clumped material from unclumped pet litter and disposes of it. The assembly comprises a base member, an open-top pet litter container rotatably mounted on the base member, a motor, a sieve member and a conveyor. The pet litter container is substantially filled with pet litter. It is for use by a pet, particularly a cat. The pet litter container rotates about the base member so that clumped and unclumped material in the container is moved into contact with the sieve member. Clumped material is separated out by the sieve and conveyed away to a waste receptacle. The waste receptacle must be periodically emptied or replaced with another waste receptacle, but typically only about once a week. 
         [0018]    Sugahara, U.S. Pat. No. 6,286,457, discloses a self-cleaning cat litter box that has the ability to automatically filter and separate clumped soiled litter and fecal matter from clean litter. The apparatus includes a rotatable drum, a spiral filter within the drum, and a stationary back plate. The drum has front and back walls, and the front wall has a front opening which permits access and egress by a domestic pet. The back wall has a first opening for both the removal of soiled litter and the addition of clean litter. The spiral filter is slotted, and is mounted on the inner surface of the drum. The stationary back plate is parallel to the plane of the back wall and has a second opening which permits the passage of soiled litter away from the drum, and a third opening to permit the passage of clean litter into the drum. The drum is rotated by a suitable drive, which can be electively actuated by a switch. The filter is configured to act as a scoop, and when the drum is at its rest position the filter is at least 10 degrees from the bottommost point on the drum. When the second opening is aligned with the first opening, passage of soiled litter from the filter into disposable collection means occurs. When the third opening is aligned with the first opening, passage of clean litter into the drum from a reservoir mounted on the back of the back plate will occur. A domestic pet includes a cat, rabbit, ferret, or skunk. 
         [0019]    Reitz, U.S. Pat. No. 6,463,881, discloses an animal litter device that includes a chamber that is rotatable about a generally horizontal axis, the chamber having a first-rotation position and a second-rotation position. An internal portion of the chamber is disposed at a bottom of the chamber when the chamber is in the its first rotation position whereat the chamber is usable by an animal, and this internal portion of the chamber is disposed generally at a top of the chamber when the chamber is in its second rotation position whereat the chamber is not usable by an animal. A dump opening is located at a second portion of the chamber, the dump opening being located at or near a top of the chamber when the chamber is in its first-rotation position, and being located at a bottom of the chamber when the chamber is in its second-rotatable position. A moisture impervious, flexible and weighted liner has boarder portions thereof fixed to the interior of the chamber, and has a weighted mid-portion covering the internal portion of the chamber and movable relative thereto. A mass of litter loosely sits on the flexible liner when the chamber is in its first rotation position. Waste separation means within the chamber operates when the chamber is rotated in a first direction between its first-rotatable position and its second-rotatable position to separate animal waste from the mass of litter, whereupon the separated animal waste exits the chamber by way of the waste opening. When the chamber is rotated in a second direction between its first-rotatable position and its second-rotatable position, the mass of litter to exits the chamber by way of the exit opening. 
         [0020]    The related art described above discloses animal excrement boxes having rotating drums with filter screens, mechanization, and means for litter exit and entry, and with somewhat complex construction. However, the prior art fails to disclose a rotating drum type litter box that is mounted for free manual rotation and yet is designed to come to rest at a selected position; and which uses an internal screen for selectively picking up waste material exclusive of non-soiled litter, and then depositing, by gravity forces, the waste material into a container that is strategically placed at a functional location adjacent to a waste door in the drum. This simple and highly effective principal is taught in the present invention. The present disclosure distinguishes over the prior art providing heretofore unknown advantages as described in the following summary. 
       BRIEF SUMMARY OF THE INVENTION 
       [0021]    This disclosure teaches certain benefits in construction and use which give rise to the objectives described below. 
         [0022]    The cat litter box, in one form or another, has been used for hundreds of years. Ultimately, it is desired to have such a pet waste depository that is self cleaning, that does not emit odors, and that provides sanitary operation. The present invention meets these needs, but additionally, is much less expensive to manufacture, pack, ship and use as will be shown in the following detailed description. The present invention is a rotational drum type cat litter box that is manually rotated to sift common litter material to capture waste on a screen that is then emptied by opening a door on the side of the drum. It is critical that the screen door be positioned just above and to one side of a receptacle so that when the door is opened, the waste material can fall by its own into the receptacle. This is accomplished by the use of a well designed base that holds both the drum and the receptacle assuring their mutual physical positions. No manual handling of the waste materials need be carried out. The drum, in the preferred embodiment, is separable into two halves, and with the end caps removed, the two halves may be nested to provide a low profile disassembled unit. This enables the apparatus to be packed in a relatively small box and can be shipped at low cost. Reassembly is easily accomplished by the consumer. Operation is highly intuitive. 
         [0023]    A primary objective inherent in the above described apparatus and method of use is to provide advantages not taught by the prior art. 
         [0024]    Another objective is to provide a cat litter box that reduces human contact with animal waste. 
         [0025]    A still further objective is to provide an improved method of use that is simple, sanitary, and effective. 
         [0026]    A further objective is to provide such a box that is able to sift litter without the use of mechanization. 
         [0027]    A still further objective is to provide such a box that is easily assembled so that it may be compactly shipped to users in a broken-down state thereby reducing shipping and packing costs. 
         [0028]    Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the presently described apparatus and method of its use. 
     
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
         [0029]    Illustrated in the accompanying drawing(s) is at least one of the best mode embodiments of the present invention In such drawing(s): 
           [0030]      FIG. 1  is a perspective view of the presently described apparatus showing a base, a drum and a waste receptacle; 
           [0031]      FIG. 2  is a perspective view of the base thereof; 
           [0032]      FIG. 3  is a perspective view of the base with the waste receptacle inserted; 
           [0033]      FIG. 4  is a perspective view of the waste receptacle with access door open; 
           [0034]      FIG. 5  is a perspective view of a portion of the interior of the drum showing a litter screen and a waste removal portal; 
           [0035]      FIG. 6  is a perspective view of a portion of the exterior of the drum showing the waste removal portal, portal door and litter screen; and 
           [0036]      FIGS. 7A-7E  are concept diagrams of the drum as viewed from one end, showing a method of use for screening and disposing of pet waste; whereby 
           [0037]      FIG. 7A  is a nominal position of the drum when used by an animal; 
           [0038]      FIG. 7B  is a position as rotated by 90° clockwise from nominal; 
           [0039]      FIG. 7C  is a position as rotated by 180° clockwise from nominal; 
           [0040]      FIG. 7D  is a position as rotated by 270° clockwise from nominal; and 
           [0041]      FIG. 7E  is as rotated by 360° clockwise to reassume the nominal position. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0042]    The above described drawing figures illustrate the described apparatus and its method of use in at least one of its preferred, best mode embodiment, which is further defined in detail in the following description. Those having ordinary skill in the art may be able to make alterations and modifications to what is described herein without departing from its spirit and scope. Therefore, it must be understood that what is illustrated is set forth only for the purposes of example and that it should not be taken as a limitation in the scope of the present apparatus and method of use. 
         [0043]    Described now in detail is a pet box apparatus providing rotational sifting of litter material  5  to separate out and dispose of waste material  7 . The apparatus may be used for any animal that can be trained to use a litter box, such as cats and dogs. The apparatus uses a support base  10  ( FIG. 2 ) having a concave drum support  20 , and adjacent thereto, a receptacle receiver  30 . The support base  10 , comprises a front strut  12 , a rear strut  14 , and, between the front and rear struts, a first  16  and second  18  side struts. Struts  12 ,  14 ,  16 , and  18  form a rectangular frame. The support base  10  further includes a medial strut  17  positioned between the first and second struts  16  and  18 . The drum support  20  extends between the medial strut  17  and the second side strut  18 . The front strut  12 , rear strut  14 , first side strut  16  and the medial strut  17  form the receptacle receiver  30  as an open rectangular frame within which a waste receptacle  40  ( FIG. 4 ) of appropriate size is inserted as a tight fit. Preferably, the waste receptacle  40  is a rectangular box with side wall panels  41  and a bottom panel  43  and a hinged door  42  which is fitted for an air-tight seal when closed to eliminate the emanation of odors from the receptacle  40 . The length of the receptacle  40  extends over the width W of the screen  60  so that any waste material in the screen  60  will drop into the receptacle  40  and not fall elsewhere. The receptacle  40  may also provide a lip  45  extensive between the receptacle  40  and drum  50  to assure collection of all particulate that may fall from screen  60  toward receptacle  40 . See  FIG. 6 . 
         [0044]    A drum  50  rests on the concave drum support  20  and drum  50  and support  20  are in intimate contact over the full range of the surface of support  20 . In this way, the drum  50 , when rested onto support  20 , although not engaged with support  20 , but merely resting on it, always is positioned in the same location relative to the receptacle receiver  30 . This is important as will be further explained. 
         [0045]    As shown in  FIG. 1 , the drum  50  is configured with a circular cylindrical wall  52  terminating at opposing front  54  and rear  56  ( FIG. 5 ) end walls. The front end wall  54  provides a pet access portal  58 . A litter screen  60  is mounted on an interior surface  55  ( FIG. 5 ) of the cylindrical wall  52  in a position adjacent to a waste disposal portal  53  as best seen in  FIGS. 5 and 6 . It should be noted that the waste receptacle  40  is positioned within the receptacle receiver  30  so that its entrance  32  is immediately below, and adjacent to, the disposal portal  53  of the drum  50  as best shown in  FIG. 6 . 
         [0046]    Preferably, the litter screen  60  is formed from a flat screening stock material with screen openings therein of such size as to allow a non-clumped animal litter material to pass through the litter screen  60  unimpeded. This action is well described in Flores, U.S. Pat. No. 5,551,375 which is hereby incorporated by reference herein. Preferably, as shown in  FIGS. 5 and 6 , the litter screen  60  is made up of a first elongate rectangular section  62  having a length approximating a spaced apart distance between the front and rear end walls  54 ,  56 . The first section  62  is bounded on each of two opposing edges by a modified triangular section  64 . As shown in  FIG. 5  the sections  64  abut the curved interior surface  55  of drum  50 . 
         [0047]    The waste disposal portal  53  is rectangular, as shown in  FIG. 6  with a width “W” approximating the length of the first section  62  of the litter screen  60 , and a height “H” sufficient for enabling the waste material  7  to pass through the disposal portal  53  from the screen  60  as will be described. 
         [0048]    The litter screen  60  is mounted on the interior surface  55  of the cylindrical wall  52  in a position for scooping and sifting the litter material  5  within the drum  50  when the drum  50  is rotated in a selected rotational sense. This process is illustrated by  FIGS. 7A  though  7 D as a sequence of rotational positions. Drum rotation, as depicted in  FIGS. 7A-7C  shows that heavier material (waste material  7 ) tends to move to the lowest position in drum  50  during rotation. The screen  60  enters the litter material, as shown in  FIG. 7D , and as it moves through the litter material  5  any animal solid waste and any clumped litter (formed from animal urination) is captured between the screen  60  and the cylindrical wall  52 . Clean litter  5  is also picked up by screen  60  but is able to move through screen  60  leaving waste material  7  remaining in the screen  60  as shown in  FIG. 7E . A waste disposal door  57  is hinged to the cylindrical wall  52  and covers the waste disposal portal  53  during drum rotation. Any form of hinge arrangement may be used and a snap-action friction lock of the door  57  is preferred. When the drum has been rotated one full turn as shown in  FIG. 7E , door  57  is opened allowing waste material  7  to drop into waste receptacle  40 . Waste receptacle door  42  is open, as shown in  FIG. 4  during the receipt of waste material  7  and is thereafter closed to eliminate odors. When the waste receptacle  40  is full, it is emptied into a proper waste container or toilet for ultimate disposal. A handle  44  is attached to the receptacle  40  to enable withdrawal of the receptacle  40  from the receptacle receiver  30  and for carrying the receptacle  40 . 
         [0049]    Rotation of drum  50  is enabled by the use of two handles  70  mounted on front end wall  54  and extending outwardly therefrom. These handles  70  are manually gripped and used to rotate drum  50  clockwise by exactly one rotation. 
         [0050]    The construction of the present invention may, of course, take many forms. Preferably, the front and rear end walls  54  and  56  have machine threads impressed on their circular peripheral edges and the ends of the cylindrical wall  52  has a female thread so that the end walls  54 ,  56  may be mounted to the cylindrical wall  52  by threaded engagement. Preferably, the drum  50  is an assembly of two half-drums  50 A and  50 B as shown in  FIG. 1 ; see parting line  51  wherein the two halves  50 A and  50 B are joined; and such joining may be by any well known technique including common fasteners. In order to pack and ship the present invention efficiently, the two halves  50 A and  50 B may be separated and nested within the support base  10 . Further disassembly and brake-down of the invention can reduce the size of a shipped unit even further. 
         [0051]    As described, the method of use of the present apparatus includes; providing the concave support base  10  and, selectively positioning adjacent thereto, the receptacle receiver  30 , resting the drum  50  on the support base  10  and placing a waste receptacle  40  into the receptacle receiver  30 . The screen  60  is mounted in axial orientation on the inside surface  55  of the cylindrical wall  52  of the drum  50  and a disposal portal is placed in the cylindrical wall  52  adjacent to the screen  60 . With a litter material  5  in the drum  50  and with waste material  7  mixed into the material  5 , the handles  70  are used to rotate the drum  50  manually thereby moving the screen  60  through the litter material  5  so as to separate the waste material  7  from the litter material  5 , the waste material  7  being captured in the screen  60 . The drum  50  is further rotated to position the screen  60  at a medial height, as shown in  FIGS. 7A and 7E , within the drum  50 , in a position immediately adjacent to the waste receptacle  40 . The waste door  57  on the cylindrical wall  52  that is positioned over and seals the waste aperture to allow the waste material to drop away from the screen into the waste receptacle. 
         [0052]    The enablements described in detail above are considered novel over the prior art of record and are considered critical to the operation of at least one aspect of the apparatus and its method of use and to the achievement of the above described objectives. The words used in this specification to describe the instant embodiments are to be understood not only in the sense of their commonly defined meanings, but to include by special definition in this specification: structure, material or acts beyond the scope of the commonly defined meanings. Thus if an element can be understood in the context of this specification as including more than one meaning, then its use must be understood as being generic to all possible meanings supported by the specification and by the word or words describing the element. 
         [0053]    The definitions of the words or drawing elements described herein are meant to include not only the combination of elements which are literally set forth, but all equivalent structure, material or acts for performing substantially the same function in substantially the same way to obtain substantially the same result. In this sense it is therefore contemplated that an equivalent substitution of two or more elements may be made for any one of the elements described and its various embodiments or that a single element may be substituted for two or more elements in a claim. 
         [0054]    Changes from the claimed subject matter as viewed by a person with ordinary skill in the art, now known or later devised, are expressly contemplated as being equivalents within the scope intended and its various embodiments. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are defined to be within the scope of the defined elements. This disclosure is thus meant to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, what can be obviously substituted, and also what incorporates the essential ideas. 
         [0055]    The scope of this description is to be interpreted only in conjunction with the appended claims and it is made clear, here, that each named inventor believes that the claimed subject matter is what is intended to be patented.