Feline litter box sieve system

A feline litter box sieve system includes a screened lid connected by a hinge to a support frame that suspends an empty litter box in the top opening of a trash receptacle. L-shaped hooks suspend the support frame in the trash receptacle. Used litter is poured from a full litter box onto the screen. Clumps and feces are retained by the screen. Pivoting the lid to an open position dumps retained clumps and feces from the screen into the trash receptacle. While the lid is open, the held litter box containing unclumped sifted litter may be removed for use.

FIELD OF THE INVENTION

This invention relates generally to feline litter boxes and more particularly to a litter sieve assembly.

BACKGROUND

A house cat owner must frequently change litter in a litter box. A litter box contains litter, typically a clay-based substance that clumps when wet. Often, the litter box is lined with a plastic bag liner, to facilitate discarding and replacing the litter.

The cat performs its excretory functions while standing on the cat litter. Cat urine soaks into the cat litter forming clumps. The cat typically buries the excrement beneath the surface of the litter.

To avoid unsanitary conditions and malodors, such clumps and buried excrement must be removed. Failure to do so no only results in highly unpleasant odors, but risks rejection of the litter box, particularly by fastidious felines.

To facilitate removal of noxious clumps of urine soaked litter and excrement, handheld sieves have been devised. These devices resemble a small shovel with a perforated scoop. The perforations typically comprise elongated parallel openings, through which unclumped litter may fall back into the box, while clumped litter and excrement is removed. Unfortunately, however, the act of thrusting the scoop into the litter tends to rip the liner and break apart clumps into small pieces. This causes much of urine soaked clumps to remain in the litter box. Additionally, many clumps and excrement droppings are easily missed by scoop. Furthermore, the process of scooping is time consuming and tedious.

What is needed is a system of sifting all clumps and excrement from the litter, quickly and reliably. Such a system should save the remaining unclumped and excrement-free litter for re-use, while discarding the clumped litter and excrement.

The invention is directed to overcoming one or more of the problems and solving one or more of the needs as set forth above.

SUMMARY OF THE INVENTION

To solve one or more of the problems set forth above, in an exemplary implementation of the invention, a feline litter box sieve system includes an assembly that is configured (i.e., sized and shaped) to be suspended in the top opening of a trash receptacle and to suspend a litter box with a flanged (i.e., flanged, rolled or bulbous) top edge in the top opening. The assembly includes a support frame, i.e., a rectilinear framework sized to fit within the top opening of the trash receptacle. The framework has opposed front and back sides and opposed first and second sides. A plurality of inwardly extending opposed flanges define a space therebetween for receiving the litter box. The plurality of inwardly extending opposed flanges are sized and positioned to support the litter box by the top flanged edge of the litter box. A plurality of suspension hooks are attached to the support frame. The suspension hooks are positioned and sized to suspend the support frame from the top edge of the trash receptacle. A lid is pivotally attached at the back side of the support frame. The lid includes a screen top with apertures. The lid is moveable by pivoting from a closed position substantially parallel to and abutting the support frame to an open position at an angle relative to the support frame. The apertures are positioned over the space defined between the inwardly extending opposed flanges when the lid is in the closed position. The distance from the front side to the back side of the support frame is less than the distance from the front to the opposed back of the top edge of the trash receptacle. The lid has a front edge, an opposed back edge, a first side edge and an opposed second side edge. The distance between the front side and back side of the support frame is about the same as a distance between the front edge and back edge of the lid. The distance between the first side and second side of the support frame is about the same as a distance between the first side edge and second side edge of the lid. The apertures of the screen top are sized to prevent passage of feline feces and clumped litter.

The lid may be pivotally attached at the back side of the support frame with a hinge or a plurality of hinges. The screen top of the lid may be expanded metal sheet. Each of the plurality of suspension hooks may be an inverted L-shaped member with a substantially horizontal top segment and a substantially vertical segment extending downwardly from the substantially horizontal top segment, the substantially vertical segment being connected to the rectilinear framework of the support frame. Each substantially vertical segment may be connected to the rectilinear framework of the support frame by a coupling extending outwardly from the rectilinear framework of the support frame. Optionally, a stay may connect the lid to the support frame and defining a limit of pivoting motion of the lid relative to the support frame. Also optionally, a handle may be attached to the lid.

In practice, two litter boxes are used with the exemplary litter sieve assembly according to principles of the invention. One litter box is suspended by the flanges of the support frame, while the assembly is suspended by the suspension hooks from the top edges of a trash receptacle. The other litter box contains used soiled litter which will poured onto the screen top of the closed lid. After pouring, this other litter box is empty (i.e., substantially empty), no longer containing soiled litter. Clumped litter and feces caught by the screen top of the lid may be dumped from the lid into the trash receptacle by raising the lid to an open position. The clumps and feces slide, roll, tumble and fall from the inclined lid into the trash receptacle. Unused litter that passes through the screen, falls into the litter box suspended from the support frame. That suspended litter box may then be removed (by lifting) from the assembly while the lid is open. That litter box, which now contains the unused (i.e., unclumped) litter, may be used as a cat litter box. If the amount of sifted unused litter is insufficient for use by cats, additional clean litter may be added to the box. Thereafter, the emptied litter box may then be suspended from the support frame while the assembly is suspended on the top edges of a trash receptacle and used to catch unused litter.

DETAILED DESCRIPTION

FIG. 1provides a top perspective view of an exemplary litter sieve assembly in a closed position according to principles of the invention. The sieve assembly includes 2 subassemblies—a lid105and a support frame130.

The support frame130is a generally rectangular cross section rectilinear framework sized to be received in a trash receptacle. More particularly, the frame130is small enough to fit into the top opening of a trash receptacle while support hooks,155,160,165,170grip top edges of the trash receptacle.

The framework of the support frame130is comprised of structural linear segments, such as triangular, rectangular, circular, elliptical, channel or L-shaped cross-section steel or aluminum segments. In a nonlimiting example, hollow rectangular cross-section steel (HSS) or aluminum segments135,140,145and150are mechanically fastened together at their ends using welds or fasteners. The segments are fastened into a generally rectangular frame with an opening that is defined by the inner periphery of the frame and sized to receive a litter box, and an outer periphery of the frame that is sized to fit within the top opening of a trash receptacle.

With reference toFIGS. 2 and 3, the support frame130includes at least a pair, or optionally a plurality of pairs, of opposed support flanges. Two opposed pairs180,185and190,195are shown inFIGS. 2, 3, 5 and 7. The support flanges180,185and190,195are positioned, sized and shaped to engage top edges of a litter box. Litter boxes are typically equipped with a curved, rolled or flanged top edge. Furthermore, they typically taper towards the bottom to provide a molding release draft angle. The space between opposed support flanges is sufficient for all but the top edges of the litter box to pass through. Thus, the flanges180,185and190,195support/suspend a litter box in the trash receptacle. A litter box300is shown suspended from the flanges180,185and190,195in the side and perspective views ofFIGS. 8 and 9as well as in the section view ofFIG. 10. The engaged flanged or rolled top edges305,310,315of the suspended litter box300are shown inFIG. 10.

While the flanges180,185and190,195are illustrated as structures extending below the framework of the support frame130, they may actually comprise the support frame. By way of example, and not limitation, the support frame may be constructed of angles (i.e., angle metal segments), each having a vertical wall and a bottom horizontal wall. The bottom horizontal walls may serve as the flanges to suspend a litter box.

A plurality of hooks extend from the sides140,150of the support frame130. In the exemplary embodiment illustrated in the figures, four separate hooks155,10,15,170are shown. However, two elongated hooks (one per side) may be used. Alternatively, more than two hooks may be used. Each hook is an inverted L-shaped bracket. The top horizontal portion of the inverted L-shaped bracket rests on top edge of the trash receptacle. Thus, the brackets extend outwardly from the sides140,150a sufficient distance for the free end of the top horizontal portion of the inverted L-shaped bracket to extend onto, and preferably beyond, the top edge of the trash receptacle. The distance by which the brackets extend outwardly depend upon the size of the particular trash receptacle. The outward extension is provided by extensions protruding from sides140,150, or by extended length front and back segments135,145, or by elongated top horizontal portions of the inverted L-shaped brackets.

The lid105is connected with hinges (hingedly mounted or pivotally mounted) to the support frame130. With reference toFIG. 3, one or more hinges200,205,210couple the back120of the lid105to the back145of the support frame130. While three barrel hinges200,205,210are illustrated, other numbers and types of pivot couplings may be used without departing from the scope of the invention, including without limitation pivot hinges, continuous (piano) hinges, and strap hinges. The hinges allow the lid105to be opened by pivoting about the barrel of the hinge.

The lid105is a generally rectangular cross section rectilinear framework having a size about the same as the support frame130. More particularly, the lid105is small enough to fit into the top opening of a trash receptacle on top of the support frame130.

The framework of the lid105is comprised of structural linear segments, such as triangular, rectangular, circular, elliptical, channel, I-, T- or L-shaped cross-section structural steel or aluminum segments. In a nonlimiting example, hollow rectangular cross-section steel (HSS) or aluminum segments110,115,120and125are mechanically fastened together at their ends using welds or fasteners. The segments are fastened into a generally rectangular frame with an opening that is defined by the inner periphery of the frame and sized to receive a litter box, and an outer periphery of the frame that is sized to fit within the top opening of a trash receptacle.

A screen175is mounted on top of the lid105. The screen175, a sieve, or sifter, separates unused litter from urine saturated clumps of litter and feline fecal waste. The mesh includes openings that allow unclumped (unused) litter to pass through, but are too small to allow clumps of litter and feces to pass through. In a nonlimiting example, the screen175is comprised of expanded sheet metal, such as expanded steel or aluminum sheet. Such expanded sheet metal is comprised of a sheet with slits that are cut or stamped into the sheet in alternating pattern that has then been stretched open in an accordion-like fashion. This process expands the cuts or slits into diamond shaped apertures of generally uniform size and shape. By way of example and not limitation, the diamond apertures may be roughly from 0.25 to 0.75 (minor [short] width) by 0.5 to 1.5 (major [long] width) inches in minor and major widths, respectively.

While an expanded sheet metal screen is shown, the invention is not limited to such a screen. Other screen materials (e.g., plastic), other screen structures (e.g., woven) and other aperture configurations (e.g., circular, elliptical or rectangular) may be used without departing from the scope of the invention.

In practice, used litter is dumped onto the screen175. The screen retains clumps of litter and feces because the apertures are too small to allow passage of the clumps and feces. Unused (unclumped) litter falls through the apertures of the screen175. In practice, an empty litter box is supported by the flanges180,185and190,195of the support frame130below the screen175. Thus, the unused litter falls into the supported litter box below the screen. The clumps of litter and feces retained by the screen are dumped into the trash receptacle by pivoting the lid about the pivot axis of the barrel of the hinges. The clumps and feces slide, roll, tumble and fall from the inclined lid into the trash receptacle.

A litter box300may be inserted into the support frame130and removed from the support frame130when the lid105is pivoted to an open position, such as shown inFIGS. 8, 9 and 10. Specifically, an empty litter box300may be inserted into the support frame130and suspended by the flanges180,185and190,195of the support frame130before the lid105is closed and used to sift urine soaked clumps and feces from unused litter. As used litter is poured onto the screen175of the lid105, when the lid is in a closed position, as shown inFIGS. 1 through 4 and 13, urine soaked clumps and feces are caught by the screen175while unused litter falls through the screen175into the box300. After sifting is completed, the lid105is pivoted to an open position, such as shown inFIGS. 8, 9 and 10, whereupon the litter box300may be removed from the support frame130and used by cats as a cat litter box. If the amount of sifted unused litter is insufficient for use by cats, additional clean litter may be added to the box300.

InFIGS. 11 and 12, the exemplary litter sieve assembly100is shown installed on a trash receptacle. The hooks155,160,165,170engage a top edge of the trash receptacle400. The lid105is shown in an open position to illustrate a space405between the back side120of the assembly100and the back edge of the trash receptacle. When the lid105is raised to the open position, debris may fall (slide, roll or fall) from the lid105directly into the trash receptacle400. Thus, the depth of the assembly100as measured from the front edges110,135to the back edges115,145, is less than the distance between the front and back edges of the top opening of trash receptacle, leaving adequate room for debris disposal. Dimensions may vary according to the size of the trash receptacle.

InFIGS. 14 and 15embodiments with stays are illustrated. The stays hold the lid105in an open position. While a cable stay500and hinged bracket stay600are shown, other types of stays may be utilized within the scope of the invention. Other stays may include a kickstand or similar spacer too hold the lid105in an open position at an acute angle relative to the support frame130.

FIGS. 16 through 19illustrate an embodiment with a lid stop605attached to the back side of the lid105between hinges (e.g., between hinges200and205). When pivoted to an open position, the lid stop605contacts the back side of the support frame130, thereby preventing further pivoting motion of the lid105. In an exemplary embodiment, the lid stop comprises a protruding prismatic structure, having a surface that contacts the back side of the support frame130when the lid105pivots to an open position suitable for dumping litter collected on the lid. In a preferred implementation, the angle of the lid relative to the support frame when the lid105is fully open is obtuse, and more preferably between 90° and 130°. An obtuse angle maintains the lid105in an open position, while an acute angle would allow the lid105to fall to a closed position and may not provide an adequate incline for dumping collected clumped litter and feces.

The assembly may be equipped with other accessories. Such other accessories may include one or more handles, spring biased hinges to facilitate opening, cushioning spacers to prevent to absorb impact when closing the lid.

An exemplary litter sieve assembly according to principles of the invention may be comprised of any material that exhibits sufficient rigidity and strength to repeatedly support a litter box and sift dumped litter. By way of example and not limitation, the lid105and support frame130may be fabricated using metal, plastic, composites, or combinations of any of the foregoing, by any suitable forming technique. For example, the lid105, support frame130, either or both, may be comprised of a plastic or polymeric material, such as natural or synthetic rubber, polyvinyl chloride (PVC), nylon, polysulfone, polyethylene, polypropylene, polystyrene, acrylics, cellulosics, acrylonitrile-butadiene-styrene (ABS) terpolymers, urethanes, thermo-plastic resins, thermo-plastic elastomers (TPE), acetal resins, polyamides, polycarbonates and/or polyesters. Preferably the chosen material is relatively inexpensive, produces a durable and strong product, is easy to use in manufacturing operations and results in an aesthetically acceptable product.

The material may optionally further include coatings or additives to provide desired properties such as desired colors, structural characteristics, glow-in-the dark properties and thermal reactivity (e.g., color changes according to heat). Illustratively, phosphorescent polymer additives, such as aluminate based phosphors, may be added to adsorb light energy and continue to release that energy as visible light, after the energy source is removed. Advantageously, such an embodiment provides a glow-in-the-dark structure that is easy to locate in a dark space.

The exemplary litter sieve assembly may be produced using any suitable manufacturing techniques known in the art for the chosen material, such as (for example) casting, forging, milling, extruding, machining, injection molding, compression molding, structural foam molding, blow molding, or transfer molding; polyurethane foam processing techniques; and vacuum forming. Preferably the manufacturing technique is suitable for mass production at relatively low cost per unit, and results in an aesthetically acceptable product with a consistent acceptable quality and structural characteristics.

In one preferred embodiment the lid and support frame are comprised of aluminum, steel or stainless steel, with pieces for each component being fastened together with mechanical fasteners or welds. In another preferred embodiment, the lid and support frame are comprised of plastics.

In practice, two litter boxes are used with an exemplary litter sieve assembly100according to principles of the invention. One litter box300is suspended from the support frame130while the assembly100is suspended on the top edges of a trash receptacle400, as described above. The other litter box contains used soiled litter which will poured onto the screen175of the closed lid105, as described above. After pouring, this other litter box is empty. Clumped litter and feces caught by the screen175of the lid105are dumped from the lid105into the trash receptacle400by raising the lid105to an open position. Unused litter that passes through the screen175, falls into the litter box300suspended from the support frame130. That litter box300may then be removed from the assembly100while the lid is open105. That litter box, which now contains the unused litter, may be used a cat litter box. The emptied litter box may then be suspended from the support frame130while the assembly100is suspended on the top edges of a trash receptacle400and used to catch unused litter in the future.

While an exemplary embodiment of the invention has been described, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. With respect to the above description then, it is to be realized that the optimum relationships for the components and steps of the invention, including variations in order, form, content, function and manner of operation, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. The above description and drawings are illustrative of modifications that can be made without departing from the present invention, the scope of which is to be limited only by the following claims. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents are intended to fall within the scope of the invention as claimed.