Abstract:
Apparatus for cleaning a cat litter box to remove lumps of excrement while leaving most of the particles of liter in the box, and for hygienically disposing of the removed lumps. The apparatus includes a flexible bag ( 32 ) with a front bag end ( 36 ) forming a main opening ( 34 ) and with a rear bag portion ( 72 ) having multiple small openings ( 70 ). A wire frame (( 40 ) holds the bag main opening in an open state, and a cardboard handle ( 42 ) holds the wire frame and bag front end. The handle is used to drag the bag forwardly through the pool of particles in the litter box while lumps larger than the small openings are captured in the bag. The handle is then slid down to close the bag, and the bag with lumps therein is disposed of as by dropping it in a garbage can.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    Homes that have an indoor household cat as a pet, usually have a litter box in which the cat excretes urine and feces. Litter in the litter box should be cleaned at intervals such as every day and the litter should be changed at less frequent intervals. Otherwise odor builds up and a fastidious cat may find other locations in a house for urination or defecation. By cleaning the litter box, a person removes much of the lumps of excrement so the litter has to be changed less frequently to save on the cost of fresh litter and the work in emptying and cleaning the box. 
         [0002]    The pool of litter particles in a litter box can be cleaned by the use of a scoop that is pushed or dragged through the pool of litter to pick up lumps of excrement. The scoop has openings that let litter particles pass through, with the openings small enough to trap lumps of excrement. The lumps are formed by lumps of feces and by the clumping together of litter particles when urine has been deposited on them. When lumps lie on the scoop, the lumps are disposed of by turning the scooper upside-down to allow the lumps to drop into a bag that is carried to a garbage can, or by holding the scooper while walking to a toilet or garbage can and dumping the lumps into the toilet or can. When disposed of in a garbage can, the clumps may attract flies. Many people find it disagreeable to handle the scooper with exposed cat feces especially if the feces is soft, or to allow the clumps to remain in a garbage can that may attract flies. Furthermore, the scooper may have to be washed if soft feces sticks to it, or left unwashed in a house. If the lumps are to be dropped into a bag, there may be difficulty in holding the bag open while dumping the lumps. A low cost apparatus that could be operated in a simple manner to scoop lumps of excrement from a litter box and quietly dispose of them and which then largely covered the lumps, and which avoided keeping a contaminated scooper in the home, would be of value. 
       SUMMARY OF THE INVENTION 
       [0003]    In accordance with one embodiment of the invention, a low cost and easily manipulated apparatus is provided that facilitates the cleaning of litter in a litter box. The apparatus includes a flexible bag with a main opening at its front end, a wire frame that holds the bag main opening open during the scooping of lumps of excrement from the pool of liter in the litter box, and a handle that supports the wire frame and bag front end and that can be slid down on the frame to close the bag main opening. The bag has smaller holes rearward of the main opening, so when the handle is moved forward to scoop litter through the bag main opening, particles of litter can pass rearward through the smaller holes but lumps of excrement cannot pass through the smaller holes and the lumps remain in the bag. 
         [0004]    After a person believes that there has been sufficient scooping of the litter box, the person presses down the handle. The handle is pushed down to slide along the wire frame and close the main opening of the bag. The apparatus with a closed main opening is carried to a waste disposal site such as a garbage can and dropped in. The fact that the bag main opening is closed helps avoid free access of flies to the lumps of excrement. Since the entire apparatus is disposed of, there are no parts to be cleaned or that will remain uncleaned in the home. 
         [0005]    The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is an isometric view of a cat litter box with lumps of excrement in the pool of litter and with the cover shown only in phantom lines. 
           [0007]      FIG. 2  is a front isometric view of an apparatus of the invention for cleaning the pool of litter in the litter box of  FIG. 1 , with the apparatus shown with its bag main opening in an open state. 
           [0008]      FIG. 3  is a rear isometric view of the apparatus of  FIG. 2 , with the bag main opening in a closed state. 
           [0009]      FIG. 4  is an enlarged view showing how particles can pass through small openings of the bag of  FIG. 2 , while lumps are trapped in the bag. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0010]      FIG. 1  shows a cat litter box  10  which includes a base  12  that holds a pool  14  of litter particles, or litter  16 . The pool  14  shown has been used by a cat, and contains lumps  20  of excrement. Some of the lumps comprise lumps of feces, while other lumps may (or may not) comprise clumps of particles held together by the effects of urine. The litter  16  can be any of a variety of materials, but is usually particles having a width and length of less than one-eighth inch long and wide and usually less than one-sixteenth inch. Bentonit, or clumping litter, is often used, which absorbs urine into clumps. A cover  22  covers the base when the box is used by a cat, but the cover is removed to clean the litter box. 
         [0011]    The litter box can be partially cleaned easily and at low cost by scooping out the lumps  20  so the remaining litter can be reused. This may be done every day or two. The litter box can be more thoroughly cleaned perhaps every three days, by emptying the box of all litter, cleaning the box, and pouring in fresh letter. The lumps  20  can be removed by moving a scooper, which is a hand-held one-piece plastic tool with slots or holes of about three-eighths inch width, through the pool of litter. Lumps are retained on the scooper but particles are not retained. As discussed above, this has the disadvantage that a person must keep a bag open while dumping feces into the bag or carry the scooper with fully exposed feces to a disposal site. In either case, when the feces is dumped into a garbage can flies often find their way to the fully exposed feces in the can. Also, the soft feces may stick to the scooper and a person may decide that it is necessary to clean the scooper. The unwashed scooper generally retains some feces, which attracts flies and other insects. 
         [0012]      FIG. 2  shows a scooper apparatus  30  of the present invention, which includes a flexible bag  32  with a main opening  34  at its front end  36 , a wire frame  40  that mounts to walls of the main opening, and a handle  42 . The bag has a lower main opening lower wall  50  and a pair of main opening side walls  52 ,  54  that are mounted or positioned on the wire frame  40 . The bag also has a main opening upper wall  56  forming a flap  58  that is fixed to the handle  42 . The handle is formed of corrugated cardboard that has vertical passages  60 , and the wire frame has upward extending arms  62 ,  64  that can slide in the cardboard passages. When the cardboard handle is pushed down, the wire frame arms  62 ,  64  slide into the handle, and the bag upper wall is moved down to lie adjacent to the lower wall, as in  FIG. 3 , so the bag is largely closed. This bag is similar to the Disposable Waste Scooper invented by applicant and described in U.S. Pat. No. 4,718,707. 
         [0013]    In accordance with the invention, applicant provides smaller, or small holes  70  in the flexible bag  32  along a bag portion that is rearward of the bag main opening  34 . The smaller holes  70  each is much smaller than the main opening  34 , and at least some, and preferably a majority, of the small holes lie in a rearward portion  72  of the main bag that lies closer to the bag rear end  74  (it is rearward during scooping) than to the bag front end  36 . However, preferably there are no hole at the extreme rearward tip  74   t . The small holes  70  prevent large lumps of excrement from passing through so such large lumps become trapped in the bag. Small lumps and unclumped litter particles readily pass through the small holes. Although small holes also may be provided in the front portion of the bag (closer to the front end  36  than the rear end), such forward small holes are not as effective in allowing particles to pass while clumps are trapped, as are the rearward holes. 
         [0014]    A person cleans litter in the litter box by removing the box cover  22 , and lowering the lower part  76  of the bag into the pool of litter so the bag is at least partially submersed. The person repeatedly drags the bag forwardly F through the litter, and lifts the bag above the pool of litter and moves the bag back to the box rear portion and down into it, after each forward dragging. The bag is moved forwardly by a person holding the handle  42  and moving it to move the frame and handle forwardly. Litter freely enters the bag main opening  34  and presses litter already in the bag to move rearward R. Most of such litter exits the bag through the small holes  70 . Lumps  20  of sufficient size cannot exit through the smaller holes so such lumps remain in the bag. 
         [0015]    After the bag has been repeatedly dragged through the litter, a considerable portion of the larger lumps lie in the bag. A person then may remove the scooper apparatus  30  from the base  12  and press the handle  42  firmly downward until the bag is closed (that is, the main opening area is preferably no more than one-tenth its original area), as shown in  FIG. 3 . The frame  40  is stationary in that the handle moves down relative to the frame and bag. The person may close the bag while the apparatus remains in the base. The person then may shake the apparatus while it lies over the base to allow particles to fall out. The person then may walk with the closed bag to a garbage can or other disposal site and throw the bag in. The bag rearward of the front end is not entirely closed because the small holes  70  remain open. However, the small holes are largely blocked by lumps, and insects such as flies do not enter small holes as readily as large openings or completely uncovered devices such as prior art scoopers that loosely support but that do not enclose lumps of excrement. The cardboard handle preferably contains instructions for using the apparatus, which is easily used especially after the operation is first viewed in a commercial or demonstration. 
         [0016]    In a scooper apparatus that applicant has constructed and successfully tested, the bag had a bag main opening  34  of a horizontal width of 4 inches and a vertical height of 2½ inches, the bag had a front-to-rear length of 6 inches and the handle had a height of 3½ inches. The small holes (36 of them) each was round and each had a diameter of ¼th inch. The bag main opening should have an opening area of a plurality of square inches, while the small holes should each have an opening area that is less than one tenth that of the main opening. The bag, the cardboard handle, and the wire frame each costs pennies, so the scooper apparatus can be constructed and sold at a low cost. 
         [0017]    Domestic cats typically weigh between four and five kilograms (nine and eleven pounds). The small holes, or small openings (which could be slots in a stronger bag) have a width of no more than one-half inch, and preferably have a diameter between one-eighth and three-eighths inch (area of 0.012 square inch and 0.11 square inch). This enables the removal of most of the volume of lumps in a litter box from such typical cats in a short period of time such as during about six scoops of the scooper apparatus. 
         [0018]    Thus, the invention provides a low cost and easily used scooper apparatus that is useful to clean litter in a litter box, and especially a cat litter box for a domestic house cat. The apparatus includes a flexible bag with a main opening at its front end and with small holes in its rear portion, a frame that is preferably a wire frame, and a handle which is preferably a corrugated cardboard handle. The scooper apparatus is used by repeatedly moving the handle forwardly above a pool of litter in a litter box while the bag main opening lies in the pool of litter, so particles and lumps enter the bag main opening and tend to move towards the rear of the bag. The larger lumps are retained while small lumps and unclumped particles pass out through the smaller holes. After the person moving the bag believes the bag is sufficiently filled with lumps (i.e. that the litter has been cleaned sufficiently), the person closes the bag main opening by pressing down the cardboard handle, and carries the bag and disposes of it in a garbage can or other disposal site. It would be possible to use a stiffer bag with slots of about one-quarter inch width to scoop the litter pool, instead of holes, but such slots are the equivalent of applicant&#39;s small holes. After the litter box has been cleaned, there is no scooper (usually contaminated with a small amount of feces) to be stored. 
         [0019]    Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art, and consequently, it is intended that the claims be interpreted to cover such modifications and equivalents.