MODULAR PET LITTER BOX SYSTEM

Abstract

A pet litter box system comprising a base tray with a non-apertured bottom wall and a plurality of sifting trays each with an apertured bottom wall, the sifting trays formed of molded pulp material. The sifting trays and base nest together. The system may include an upper shield seated on the nested sifting trays to contain litter that is kicked up by a cat utilizing the tray system. The shield may be formed of pulp and inverted to receive nested pulp sifting trays to define a transport or storage mode, the shield enhancing the combined structure in the transport or storage mode.

Claims

1. A sifting tray formed from pulp material, the tray comprising an apertured bottom wall and four sidewall portions comprising two opposing end sidewall portions and two opposing lateral sidewall portions, each of the four sidewall portions extending upwardly from a periphery of the apertured bottom wall, the apertured bottom wall and the four sidewall portions all unitary with each other; wherein the apertured bottom wall having a planar lowermost wall portion extending between each of the four sidewall portions at a lowermost level; and wherein the apertured bottom wall having a plurality of elongate openings.

2. The sifting tray of claim 1, wherein the apertured bottom wall has a plurality of ribs projecting upwardly from the lowermost wall portion of the apertured bottom wall, each rib having a flattened top, and wherein the flattened tops define an uppermost wall portion of the bottom wall.

3. The sifting tray of claim 2, wherein at least one rib extends from each of the four sidewall portions.

4. The sifting tray of claim 2, wherein the planar lowermost wall portion extends uninterrupted from each corner of the sifting tray towards a center of the sifting tray such that an “X” shape is formed between the plurality of ribs and openings.

5. The sifting tray of claim 2, wherein a singular traverse extends from a first lateral sidewall portion to the end to the opposite lateral sidewall uninterrupted by a rib.

6. The sifting tray of claim 1, wherein the pulp is formed of at least one of recycled cardboard, grasses, bagasse, or bamboo.

7. The sifting tray of claim 1, wherein the pulp material has a thickness of about 1.5 mm.

8. The sifting tray of claim 1, wherein each corner of the tray comprises an uninterrupted bottom wall portion.

9. The sifting tray of claim 1, wherein the sifting tray is configured to nest within a second sifting tray.

10. The sifting tray of claim 1, wherein the pulp material has a thickness of about 1.5 mm.

11. The sifting tray of claim 1, wherein the sifting tray has a weight of about 147 grams.

12. A modular pet litter box system comprising a pulp formed sifting tray, the pulp formed sifting tray comprising an apertured bottom wall with at least four rows of alternating elongate sifting openings and upwardly extending ribs, each sifting opening positioned at a lowermost level of the apertured bottom wall.

13. The modular pet litter box system of claim 12, wherein each rib comprises a flat horizontal plateau portion and, each of said horizontal plateau portion of each rib at an upper level of the apertured bottom wall.

14. The modular pet litter box system of claim 12, wherein the sifting tray comprises four sidewall portions surrounding the apertured bottom wall.

15. The modular pet litter box system of claim 14, wherein each of the four rows of sifting openings extends from a different sidewall portion.

16. The modular pet litter box system of claim 12, further comprising a base tray defining a cavity configured to retain cat litter.

17. The modular pet litter box system of claim 16, further comprising a high shield portion that is conformingly sized to seat on lip portions of the sifting trays.

18. A sifting tray formed from pulp material, the tray comprising a bottom wall and four sidewall portions comprising two opposing end sidewall portions and two opposing lateral sidewall portions, each of the four sidewall portions extending upwardly from a periphery of the bottom wall, the bottom wall and the four sidewall portions all unitary with each other; wherein the bottom wall having a first cluster of a plurality of elongate and straight ribs and a plurality of elongate and straight slots positioned at a first lateral sidewall of the sifting tray; and the bottom wall having a second cluster of a plurality of elongate and straight ribs and a plurality of elongate and straight slots positioned at an opposite lateral sidewall of the sifting tray.

19. The sifting tray of claim 18, wherein the bottom wall of the sifting tray has a non-ribbed and non-slotted planar bottom portion positioned between said first cluster and said second cluster.

20. The sifting tray of claim 19, wherein two non-ribbed and non-slotted straight planar bottom portions define an X-shape in the bottom wall of the sifting tray.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0061] FIG. 1A is a perspective front view of a modular pet litter box system according to an embodiment of the disclosure.

[0062] FIG. 1B is an exploded perspective front view of a modular pet litter box system according to an embodiment of the disclosure.

[0063] FIG. 2A is a perspective top view of a base tray according to an embodiment of the disclosure.

[0064] FIG. 2B is a perspective bottom view of a base tray according to an embodiment of the disclosure.

[0065] FIG. 2C is a top view of a base tray according to an embodiment of the disclosure.

[0066] FIG. 2D is a side view of a base tray according to an embodiment of the disclosure.

[0067] FIG. 2E is a front view of a base tray according to an embodiment of the disclosure.

[0068] FIG. 3A is a perspective top view of a high shield according to an embodiment of the disclosure.

[0069] FIG. 3B is a perspective bottom view of a high shield according to an embodiment of the disclosure.

[0070] FIG. 3C is a top view of a high shield according to an embodiment of the disclosure.

[0071] FIG. 3D is a side view of a high shield according to an embodiment of the disclosure.

[0072] FIG. 3E is a back view of a high shield according to an embodiment of the disclosure.

[0073] FIG. 3F is a front view of a high shield according to an embodiment of the disclosure.

[0074] FIG. 4A is a perspective top view of a sifting tray according to an embodiment of the disclosure.

[0075] FIG. 4B is a perspective bottom view of a sifting tray according to an embodiment of the disclosure.

[0076] FIG. 4C is a top view of a sifting tray according to an embodiment of the disclosure.

[0077] FIG. 4D is a side view of a sifting tray according to an embodiment of the disclosure.

[0078] FIG. 4E is a perspective top view of a sifting tray according to an embodiment of the disclosure.

[0079] FIG. 4F is a perspective bottom view of a sifting tray according to an embodiment of the disclosure.

[0080] FIG. 4G is a top view of a sifting tray according to an embodiment of the disclosure.

[0081] FIG. 4H is a side view of a sifting tray according to an embodiment of the disclosure.

[0082] FIG. 5A is a perspective view of nested sifting trays in a use configuration according to an embodiment of the disclosure.

[0083] FIG. 5B is a cross-sectional view of nested sifting trays in a use configuration according to an embodiment of the disclosure taken at line 5B-5B of FIG. 5A.

[0084] FIG. 5C is a perspective view of nested sifting trays according to an embodiment of the disclosure.

[0085] FIG. 5D is a cross-sectional view of nested sifting trays in a compact shipping configuration according to an embodiment of the disclosure taken at line 5D-5D of FIG. 5C.

[0086] FIG. 5E is a cross-sectional view of a bottom wall portion of the bottom wall at a sifting opening.

[0087] FIG. 5F is a perspective view of nested sifting trays in a use configuration according to an embodiment of the disclosure.

[0088] FIG. 5G is a cross-sectional view of nested sifting trays in a use configuration according to an embodiment of the disclosure taken at line 5G-5G of FIG. 5F.

[0089] FIG. 5H is a perspective view of nested sifting trays according to an embodiment of the disclosure.

[0090] FIG. 5I is a cross-sectional view of nested sifting trays in a compact shipping configuration according to an embodiment of the disclosure taken at line 5I-5I of FIG. 5H.

[0091] FIG. 6A is a top perspective view of a pet litter box system in a shipping configuration.

[0092] FIG. 6B is a bottom perspective view of a pet litter box system in a shipping configuration.

[0093] FIG. 6C is an exploded perspective view of a pet litter box system in a shipping configuration.

[0094] FIG. 6D is a perspective view of a pet litter box system in a shipping configuration with a label therein.

[0095] FIG. 6E is a perspective view of a pet litter box system in a shipping configuration with a label therein, a bag of pet litter therein, and a bag enclosing same.

[0096] FIG. 7 illustrates a method of using a pet litter box system.

DETAILED DESCRIPTION

[0097] Referring to FIGS. 1A-1B, a modular pet litter box system 100 is illustrated in a use configuration having a disposable base tray 101, a lid or disposable high shield 121, and at least one disposable sifting tray 141. Sifting trays 141 nest within base tray 101. Lid 121 sits atop the nested trays 101, 141 and an enlarged edge portion 123 of lid 121 surrounds the upper periphery of nested trays 101, 141. A stack 145 of one or more sifting trays 141 in a use configuration may further be nested within base 101.

[0098] Referring to FIGS. 2A-2E, base tray 200 has a unitary bottom wall 201, front wall 203 opposite rear wall 205, and left wall 207 opposite right wall 209. Walls 203, 205, 207, 209 extend upwardly along a vertical axis from bottom wall 201. In embodiments, walls 203, 205, 207, 209 join one another at right angles. In embodiments, walls 203, 205, 207, 209 join one another at rounded corners. In embodiments, walls 203, 205, 207, 209 define a 90 degree angle 211 with bottom wall 201. In embodiments, walls 203, 205, 207, 209 define an angle 211 greater than 90 degrees with bottom 201. In embodiments angle 211 is between 90 degrees and 140 degrees. In embodiments, angle 211 is 110 degrees. In embodiments, walls 203, 205, 207, 209 and bottom wall 201 define a bowl like cavity capable of retaining items such as granular litter or additional trays.

[0099] In embodiments, a circumferential lip 213 surrounds a top peripheral edge of base tray 200. Circumferential lip 213 may have a vertical height 215 between 0.1 inches and 1 inch and a horizontal projection 217 between 0.2 inches and 1 inch. In embodiments, vertical height 215 is 0.2 inches. In embodiments, horizontal projection 217 is 0.5 inches. Base tray 200 may have a width 219 between 11 and 18 inches and a length 221 between 15 and 20 inches in the horizontal plane. Base tray 200 may have a vertical height 223 between 2.5 and 5.5 inches.

[0100] Referring to FIGS. 3A-3F, high shield 300 has a top portion 301 opposite a bottom portion 302, front wall 303 opposite rear wall 305, and left wall 307 opposite right wall 309. Walls 303, 305, 307, 309 extend upwardly along a vertical axis. In embodiments, walls 303, 305, 307, 309 join one another at right angles. In embodiments, walls 303, 305, 307, 309 join one another at rounded corners. In embodiments, walls 303, 305, 307, 309 define a circumferential ring. The circumferential ring can provide a shield that may prevent litter being sprayed outside modular pet litter box system 100 when an animal paws at the litter, for example, during an attempt to bury excrement. In embodiments, top portion 301 is open. In embodiments, top portion 301 is unitary, forming a solid lid. In embodiments, an enlarged edge portion 313 surrounds a bottom peripheral edge of lid or shield 300. Enlarged edge portion 313 may have a vertical height 315 between 0.5 inches and 3 inches and an inward horizontal projection 316 between 0.05 inches and 1 inch. In embodiments, shield bottom edge portion 302 configured as a skirt portion 303 and a shoulder portion 304 has a width 321 of between 12 and 22 inches that is wider and/or longer dimensionally than shield top portion 301 width 321 when measured in the horizontal plane. In embodiments, bottom portion 302 has a length 319 between 16 and 25 inches. In embodiments, bottom portion 302 has a width 321 of between 16 and 25 inches. In embodiments, top portion 301 has a length 325 between 15 and 24 inches and is less than the length of the bottom portion. In embodiments, top portion 301 has a width 327 between 14 and 24 inches and is less than the width of the bottom portion. In embodiments, enlarged edge portion 313 may have a slight outward taper towards the bottom peripheral edge of lid 300. In embodiments, the slight outward taper be between 90 and 100 degrees. A slight outward taper may be advantageous for lid enlarged edge portion 313 to surround other elements of modular pet litter box system 100.

[0101] In embodiments front wall 303 is vertically shorter than rear wall 305. In embodiments, left and right walls 307, 309 taper towards front wall 303. In embodiments, lid 300 has a vertical height 323 between 3 and 8 inches.

[0102] Referring to FIGS. 4A-4D, sifting tray 400 has a bottom wall 401, front wall 403 opposite rear wall 405, and left wall 407 opposite right wall 409. Walls 403, 405, 407, 409 extend upwardly along a vertical axis from bottom wall 401. In embodiments, walls 403, 405, 407, 409 join one another at right angles. In embodiments, walls 403, 405, 407, 409 join one another at rounded corners. In embodiments, walls 403, 405, 407, 409 define a 90 degree angle 411 with bottom wall 401. In embodiments, walls 403, 405, 407, 409 define an angle 411 greater than 90 degrees with bottom wall 401. In embodiments angle 411 is between 90 degrees and 140 degrees. In embodiments, angle 411 is 105 degrees. In embodiments, angle 411 of sifting tray 400 generally matches angle 211 of base tray 200. In embodiments, walls 403, 405, 407, 409 and bottom wall 401 define a bowl like cavity capable of retaining items such as solid excrement or additional trays.

[0103] In embodiments, a circumferential lip 413 surrounds a top peripheral edge of sifting tray 400. Circumferential lip 413 may have a vertical height 415 between 0.1 inches and 1 inch and a horizontal projection 417 between 0.2 inches and 1 inch. In embodiments, vertical height 415 is 0.2 inches. In embodiments, horizontal projection 417 is 0.5 inches. Sifting tray 400 may have a width 420 between 12 and 22 inches and a length 421 between 16 and 25 inches in the horizontal plane. Sifting tray 400 may have a vertical height 423 between 4 and 8 inches.

[0104] In embodiments, sifting tray 400 may have openings 431 that are flush with the bottom panel 401 and surface of the sifting tray. A sifting tray 400 may have ribs 433 with flattened top surfaces 434, such that the structure is suitable termed a plateaus 433 extending upwardly from the bottom surface 401 of the sifting tray 400. Ribs or plateaus 433 may be generally rectilinear in shape. Ribs or plateaus 433 may have a height 419 between 0.1 and 1.0 inches. In embodiments, ribs or plateaus 433 may have rounded corners. Ribs or plateaus 433 may be either uniform or staggered. Ribs or plateaus 433 may extend from walls 403, 405, 407, 409. In embodiments, ribs or plateaus 433 be self-contained such that they do not contact a wall 403, 405, 407, 409. In embodiments, a portion of ribs or plateaus 433 may conform to the shape of wall 403, 405, 407, 409 or corners of sifting tray 400. In embodiments, ribs or plateaus 433 may extend upwardly from bottom wall 401 between 0.1 and 1.0 inches. Openings 431 are illustrated as elongate but may be a variety of shapes. For example, openings 431 may be oblong, circular, oval, rectangular, triangular, or any other suitable shape configured to act like a sieve. Openings 431 may be generally uniform throughout. In embodiments, openings 431 may take on a variety of shapes or sizes throughout the sifting tray 400. For example, in embodiments, an opening 431 closer to a corner of sifting tray 400 may have a different size or shape than a more centrally situated opening 431. In embodiments, opening 431 may have a length 451 between 1 and 3 inches. In embodiments, opening 431 may have a width 455 between 0.1 and 0.5 inches.

[0105] In embodiments, the bottom wall of the sifting trays does not have a traverse on the planar top surface that extends from end to opposite end or side to opposite side that is uninterrupted by a rib. Moreover, in embodiments, no rib extends all the way from one lateral sidewall 461 to the opposing lateral sidewall 462, nor from an end sidewall 463 to an opposing end sidewall 464. This lack of linear spanning bottom wall portion provides structural rigidity facilitating the use of pulp materials for the sifting tray. Moreover, in embodiments, each elongate sifting opening is not positioned laterally adjacent to another elongate sifting opening without ribs being therebetween. In embodiments, most of the elongate sifting openings are not positioned laterally adjacent to another elongate opening without ribs being therebetween. In embodiments, the length of the openings of the sifting trays is limited to less than 3 inches and a width less than about 0.5 inches. In embodiments, the grid is laid out with two rows of elongate ribs or plateaus alternating with elongate openings, the directions of the elongations of each of the elongate ribs or plateaus and each of the openings being traverse to the direction that said row extends. In embodiments, the bottom wall has two rows of alternating elongate ribs or plateaus and elongate openings. In an embodiment with two rows of alternating ribs or plateaus and elongate openings, each elongate rib or plateau in one row is aligned with one or more elongate openings in the other row. And accordingly, each elongate opening in one row is aligned with an elongate rib or plateau in the other row. In embodiments each row has at least 6 ribs or plateaus and at least 6 or more elongate openings. In embodiments each row has less than 15 ribs or plateaus and less than 15 or more laterally arranged elongate openings. In embodiments, the layout may be changed by adding more or less, or bigger or smaller openings 431 to allow litter to pass through. Differences in the shape, size, depth, and angle of ribs 433 are within the scope of this disclosure.

[0106] Continuing to refer to FIGS. 4A-4D, and also referring to FIG. 5E, in embodiments, the ribs 433 project upwardly 0.17 to 0.30 inches from the top surface 434 of a lowermost level of the bottom wall. The ribs may have a horizontal width of from 0.40 to 1.0 inches and a length of from 2 inches to 8 inches. The corner 436 between the top planar surface 437 of the lowermost level 439 and the projecting rib may have a radius of curvature 441 of greater than 0.05 inches in embodiments. In embodiments, the radius of curvature may be greater than 0.08 inches. In embodiments, the radius of curvature may be greater than 0.12 inches. The radius of curvature of the corner 450 between the bottom wall and each of the outwardly canted sidewalls may be greater than 0.05 inches, in embodiments greater than 0.08 inches, in embodiments greater than 0.12 inches. The corners with relatively large diameter radius of curvature, and the horizontal planar walls on the opposing sides of the openings 431 facilitate horizontal sliding of the litter 460 and debris 461 in the tray. The openings 431 are defined by planar horizontal wall portions 470 with edges 472 at the opening. The length or height 477 of the opening equals the thickness of the wall portion at the opening.

[0107] Sifting tray 400 may have indicia to easily permit a user to determine an orientation of the sifting tray 400, the purpose of which is explained below. In embodiments, indicia may be a notch 441 in the circumferential lip 413 of sifting tray 400. In embodiments, indicia may be a marking 443 embossed in bottom wall 401 or ribs or plateaus 433. For example, marking 443 may be an arrow. Other visible indicia in the forms of markings, notches, or the like are not beyond the scope of this disclosure.

[0108] Referring to FIGS. 4E-4H, sifting tray 800 has a bottom wall 801, front wall 803 opposite rear wall 805, and left wall 807 opposite right wall 809. Walls 803, 805, 807, 809 extend upwardly along a vertical axis from bottom wall 801. In embodiments, walls 803, 805, 807, 809 join one another at right angles. In embodiments, walls 803, 805, 807, 809 join one another at rounded corners. In embodiments, walls 803, 805, 807, 809 define a 90 degree angle 811 with bottom wall 801. In embodiments, walls 803, 805, 807, 809 define an angle 811 greater than 90 degrees with bottom wall 801. In embodiments angle 811 is between 90 degrees and 140 degrees. In embodiments, angle 811 is 105 degrees. In embodiments, angle 811 of sifting tray 800 generally matches angle 211 of base tray 200. In embodiments, walls 803, 805, 807, 809 and bottom wall 801 define a bowl like cavity capable of retaining items such as solid excrement or additional trays.

[0109] In embodiments, a circumferential lip 813 surrounds a top peripheral edge of sifting tray 800. Circumferential lip 813 may have a vertical height 815 between 0.1 inches and 1 inch and a horizontal projection 817 between 0.2 inches and 1 inch. In embodiments, vertical height 815 is 0.2 inches. In embodiments, horizontal projection 817 is 0.5 inches. Sifting tray 800 may have a width 820 between 12 and 22 inches and a length 421 between 16 and 25 inches in the horizontal plane. Sifting tray 800 may have a vertical height 423 between 4 and 8 inches. In embodiments, a thickness of sifting tray 800 is between 0.02 and 0.2 inches. In embodiments, a thickness of sifting tray 800 is about 0.06 inches. In embodiments, sifting tray 800 weighs between 120 and 175 grams. In embodiments, sifting tray 800 weighs about 147 grams.

[0110] In embodiments, sifting tray 800 may have openings 831 that are flush with the bottom panel 801 and surface of the sifting tray. A sifting tray 800 may have ribs 833 with flattened top surfaces 834, such that the structure is suitable termed a plateau 833 extending upwardly from the bottom surface 801 of the sifting tray 800. Ribs or plateaus 833 may be generally rectilinear in shape. Ribs or plateaus 833 may have a height 819 between 0.1 and 1.0 inches. In embodiments, ribs or plateaus 833 may have rounded corners. Ribs or plateaus 833 may be either uniform or staggered. Ribs or plateaus 833 may extend from walls 803, 805, 807, 809. In embodiments, ribs or plateaus 833 be self-contained such that they do not contact a wall 803, 805, 807, 809. In embodiments, a portion of ribs or plateaus 833 may conform to the shape of wall 803, 805, 807, 809 or corners of sifting tray 800. In embodiments, ribs or plateaus 833 may extend upwardly from bottom wall 801 between 0.1 and 1.0 inches. Openings 831 are illustrated as elongate but may be a variety of shapes. For example, openings 831 may be oblong, circular, oval, rectangular, triangular, or any other suitable shape configured to act like a sieve. Openings 831 may be generally uniform throughout. In embodiments, openings 831 may take on a variety of shapes or sizes throughout the sifting tray 800. For example, in embodiments, an opening 831 closer to a corner of sifting tray 800 may have a different size or shape than a more centrally situated opening 831. In embodiments, opening 831 may have a length 851 between 0.1 and 12.5 inches. In embodiments, opening 831 may have a width 855 between 0.1 and 0.5 inches.

[0111] In embodiments, the bottom wall of the sifting trays does not have a traverse on the planar top surface that extends from end to opposite end or side to opposite side that is uninterrupted by a rib. In embodiments, the bottom wall of the sifting trays has a singular traverse on the planar top surface that extends from end to opposite end or side to opposite side that is uninterrupted by a rib. In embodiments, the singular uninterrupted traverse is centrally located on the sifting tray. Moreover, in embodiments, no rib extends all the way from one lateral sidewall 861 to the opposing lateral sidewall 862, nor from an end sidewall 863 to an opposing end sidewall 864. This lack of linear spanning bottom wall portion provides structural rigidity facilitating the use of pulp materials for the sifting tray. Moreover, in embodiments, each elongate sifting opening is not positioned laterally adjacent to another elongate sifting opening without ribs being therebetween. In embodiments, most of the elongate sifting openings are not positioned laterally adjacent to another elongate opening without ribs being therebetween. In embodiments, the length of the openings of the sifting trays is limited to less than half the length of the sifting tray and a width less than about 0.5 inches. In embodiments, a grid is laid out such that each wall 803, 805, 807, 809 has ribs and openings extending from the wall towards the center of the sifting tray, with no rib or opening intersecting one another or originating from a corner. In such a pattern, when viewed from the top, the flat floor portion of the tray appears to form an “X” shape. In embodiments, the “X” portion is intersected by a singular uninterrupted traverse through the middle extending from one sidewall to an opposing sidewall. The uninterrupted portions of the sifting tray floor extending generally from corner to corner creates added structural stability for the sifting tray. The uninterrupted traverse further adds to the structural stability. In embodiments, a lack of ribs or plateaus in the corners aids in sifting by preventing litter from pooling in the corners and not sifting out through the openings. In embodiments, the grid is laid out with four rows of elongate ribs or plateaus alternating with elongate openings, the directions of the elongations of each of the elongate ribs or plateaus and each of the openings being traverse to the direction that said row extends. In embodiments, the bottom wall has four rows of alternating elongate ribs or plateaus and elongate openings. In an embodiment with four rows of alternating ribs or plateaus and elongate openings, each elongate rib or plateau in a first row is aligned with one or more elongate openings in a second opposite row, and each elongate rib or plateau in a third row is aligned with one or more elongate ribs or plateaus in a fourth opposite row. In embodiments each row has at least 5 ribs or plateaus and at least 5 or more elongate openings. In embodiments each row has less than 15 ribs or plateaus and less than 15 laterally arranged elongate openings. In embodiments, the layout may be changed by adding more or less, or bigger or smaller openings 831 to allow litter to pass through. Differences in the shape, size, depth, and angle of ribs 833 are within the scope of this disclosure.

[0112] In embodiments, a sifting tray for cat litter 800 has a bottom wall 801 with a first cluster 828.1 of a plurality of elongate and straight ribs and a plurality of elongate and straight slots positioned at a lateral sidewall 807 of the sifting tray, the bottom wall 801 having a second cluster 828.2 of a plurality of elongate and straight ribs and a plurality of elongate and straight slots positioned at an opposite lateral sidewall 809 of the sifting tray. In embodiments, said bottom wall of the sifting tray has a third cluster 828.3 of a plurality of elongate and straight ribs and a plurality of elongate and straight slots positioned at an end sidewall 803 of the sifting tray. In embodiments, said bottom wall of the sifting tray has a fourth cluster 828.4 of a plurality of elongate and straight ribs and a plurality of elongate and straight slots positioned at an opposite end sidewall 805 of the sifting tray. In embodiments, a sifting tray 800 may have from 4 to 8 clusters 828 of a plurality of elongate and straight ribs and a plurality of elongate and straight slots positioned at sidewalls.

[0113] In embodiments, a sifting tray has 800 on a bottom wall 801 with a first cluster 828.1 of alternating ribs and slots that each extend in a common first direction and a second cluster 828.2 of alternating ribs and slots that each extend in a common second direction different from the first on said bottom wall 801. In embodiments, said bottom wall 801 of the sifting tray 800 has a non-ribbed and non-slotted planar bottom portion 826 positioned between said first cluster and said second cluster. In embodiments, the non-ribbed and non-slotted planar bottom portion 826 is linear and extends one of lengthwise, widthwise, and diagonally. In embodiments, there are two non-ribbed and non-slotted straight planar bottom portions 826 that define an X-shape in the bottom wall of the sifting tray.

[0114] Continuing to refer to FIGS. 4E-4H, and also referring to FIG. 5E, in embodiments, the ribs 833 project upwardly 0.10 to 0.30 inches from the top surface 834 of a lowermost level of the bottom wall. The ribs may have a horizontal width of from 0.40 to 1.0 inches and a length of from 2 inches to 12.5 inches. The corner 836 between the top planar surface 837 of the lowermost level 839 and the projecting rib may have a radius of curvature 841 of greater than 0.05 inches in embodiments. In embodiments, the radius of curvature may be greater than 0.08 inches. In embodiments, the radius of curvature may be greater than 0.12 inches. The radius of curvature of the corner 850 between the bottom wall and each of the outwardly canted sidewalls may be greater than 0.05 inches, in embodiments greater than 0.08 inches, in embodiments greater than 0.12 inches. The corners with relatively large diameter radius of curvature, and the horizontal planar walls on the opposing sides of the openings 831 facilitate horizontal sliding of the litter 860 and debris 861 in the tray. The openings 831 are defined by planar horizontal wall portions 870 with edges 482 at the opening. The length or height 877 of the opening equals the thickness of the wall portion at the opening.

[0115] Sifting tray 800 may have indicia to easily permit a user to determine an orientation of the sifting tray 800, the purpose of which is explained below. In embodiments, indicia may be a notch 841 in the circumferential lip 813 of sifting tray 800. In embodiments, indicia may be a marking 843 embossed in a sidewall of sifting tray 800. In embodiments, indicia may be a marking embossed in bottom wall or ribs or plateaus. For example, marking may be an arrow. Other visible indicia in the forms of markings, notches, or the like are not beyond the scope of this disclosure.

[0116] Referring to FIGS. 5A-5D, sifting trays 510, 512 may be combined in a stack 500 in a use configuration. The openings 531 flush with the bottom panel 501 are blocked by the ribs flattened top surfaces 532 or plateaus 537 of a like tray 512, rotated 180 degrees, and stacked below the sifting tray 510. Similarly, the ribs or plateaus 533 may have flat surfaces 535 that are positioned such that each engage and block the openings of a like tray, rotated 180 degrees, stacked above the sifting tray 510. Although FIG. 5A illustrates only two sifting trays 510, 512, any number of trays 510, 512 is not beyond the scope of this disclosure. One skilled in the art will appreciate that additional sifting trays 510 may be added above a top most or below a bottom most tray 510,512 and be incorporated into stack 510. So long as each tray 510 is rotated 180 degrees as compared to a tray 512 immediately above or below, openings 531 will continue to be blocked by ribs or plateaus 537. The blocking of the openings creates a barrier inhibiting the flow of litter so that litter does not pass downwardly through the openings to a lower sifting tray unless and until the sifting tray is lifted. In embodiments, ribs or plateaus 537 may have an upwardly extending projection or crown 516 that extends into openings 531 of the tray thereabove 510, thereby further inhibiting the downward flow of litter. In embodiments, sifting trays 510, 512 may be nested in the same orientation creating a stack 500 in a shipping configuration. In a shipping configuration openings 531 of sifting tray 510 align with openings 539 of a tray 512 immediately below. While the shipping configuration is not conducive to retaining contents, such as litter, within sifting trays 510, 512, it does have the advantage of reducing space between trays 510, 512. One will appreciate that as more trays 510 are incorporated into stack 500, this space saving becomes compounded. One will further appreciate that as additional trays 510 are incorporated into the stack 500, transitioning a stack 500 between a use and a shipping configuration entails ensuring that each tray 510 is rotated 180 degrees as compared to a tray 512 either immediately above or below tray 510. As discussed above, trays 510, 512 may have indicia to facilitate this task. When each tray 510 in a stack 500 has indicia in alignment, it is readily apparently to the user that stack 500 is in a shipping configuration and therefore objects such as litter will pass through stack 500. Similarly, a user can readily ascertain that when indicia alternate between adjacent trays 510, stack 500 is in a use configuration and will inhibit contents such as litter from flowing downward from one tray 510 to the next tray 512.

[0117] Referring to FIGS. 5F-5I, sifting trays 910, 912 may be combined in a stack 900 in a use configuration. The openings 931 flush with the bottom panel 901 are blocked by the ribs flattened top surfaces 932 or plateaus 937 of a like tray 912, rotated 180 degrees, and stacked below the sifting tray 910. Similarly, the ribs or plateaus 933 may have flat surfaces 935 that are positioned such that each engage and block the openings of a like tray, rotated 180 degrees, stacked above the sifting tray 910. Although FIG. 5F illustrates only two sifting trays 910, 592, any number of trays 910, 912 is not beyond the scope of this disclosure. One skilled in the art will appreciate that additional sifting trays 910 may be added above a top most or below a bottom most tray 910,912 and be incorporated into stack 910. So long as each tray 910 is rotated 180 degrees as compared to a tray 912 immediately above or below, openings 931 will continue to be blocked by ribs or plateaus 937. The blocking of the openings creates a barrier inhibiting the flow of litter so that litter does not pass downwardly through the openings to a lower sifting tray unless and until the sifting tray is lifted. In embodiments, ribs or plateaus 937 may have an upwardly extending projection or crown 916 that extends into openings 931 of the tray thereabove 910, thereby further inhibiting the downward flow of litter. In embodiments, sifting trays 910, 912 may be nested in the same orientation creating a stack 900 in a shipping configuration. In a shipping configuration openings 931 of sifting tray 910 align with openings 939 of a tray 912 immediately below. While the shipping configuration is not conducive to retaining contents, such as litter, within sifting trays 910, 912, it does have the advantage of reducing space between trays 910, 912. One will appreciate that as more trays 910 are incorporated into stack 900, this space saving becomes compounded. One will further appreciate that as additional trays 910 are incorporated into the stack 900, transitioning a stack 900 between a use and a shipping configuration entails ensuring that each tray 910 is rotated 180 degrees as compared to a tray 512 either immediately above or below tray 910. As discussed above, trays 910, 912 may have indicia to facilitate this task. When each tray 910 in a stack 900 has indicia in alignment, it is readily apparently to the user that stack 900 is in a shipping configuration and therefore objects such as litter will pass through stack 900. Similarly, a user can readily ascertain that when indicia alternate between adjacent trays 910, stack 900 is in a use configuration and will inhibit contents such as litter from flowing downward from one tray 910 to the next tray 912.

[0118] During transport or storage of a stack 500, 900 or pet litter box system 100, it may be advantageous to reduce the amount of space consumed by stack 500, 900 or the system 100. To further reduce the space consumed by pet litter box system 600, as depicted in FIGS. 6A-6E, lid 621 may be inverted and base 601 inserted into lid 621 such that bottom wall 603 of base 601 is situated generally within an upper portion 625 of lid 621. A stack 645 of one or more sifting trays 641.1, 641.2, 641.3 in a shipping configuration may further be nested within base 601. The three sifting trays may be aligned as illustrated in FIG. 6C for maximum compactness or the middle of three sifting trays may rotated 180° to be in a ready-to-use configuration. Even though lid 601 is inverted, it will be appreciated that enlarged edge portion 623 still surrounds the upper periphery of trays 601, 641. By capturing trays 601, 641 within the enlarged edge portion 623, trays 601, 641 will not readily slide or otherwise separate from one another during shipping or in storage. As many bulk transport carriers base fees upon shipping size, minimizing space consumed in a shipping configuration may result in beneficial cost savings. Stacking trays 601, 641 within inverted lid 621 as described may add further structural support to the system 600. Crushability is a consideration for shipping and storage. The added rigidity found from stacking the components of system 600 as described may reduce damage incurred from external forces such as during shipping. Further, a kit 650 is contemplated which might include any combination of a lid 621, a base 601, one or more sifting trays 641, one or more bags of litter 653. In embodiments, bags of litter 653 may be placed within the uppermost tray 641 of system 600, such that the kit is in a compact unit. A cardboard label 658 with graphic bridges across the upper sifting tray or along the sides and bottom and bag of litter. A plastic transparent bag 660 may enclose the entire kit.

[0119] Referring to FIG. 7, a method of using a modular pet litter box system includes providing a modular pet litter box system in the shipping configuration 701. The high shield is removed and each of the at least two disposable sifting trays are separated 702. Each of the at least two disposable sifting trays are oriented and nested such that the upwardly extending ribs of a first sifting tray block the sifting openings of a sifting tray nested immediately above the first sifting tray 703. The oriented and nested sifting trays, in a use configuration, are placed within the base tray 704. A top most disposable sifting tray is filled with a granular material 705. The high shield is placed atop the top most disposable sifting tray 706. A pet is permitted to place waste in the top most disposable sifting tray 707. The granular material is sifted to an adjacent disposable sifting tray while retaining the pet waste in the top most disposable sifting tray 708. The top most disposable sifting tray is disposed of along with the pet waste retained therein 709. In embodiments, a user may desire to reuse the top most disposable sifting tray and return it to the stack of nested sifting trays for additional use 710.

[0120] A pet litter box system offers a modular design and is customizable for a user to purchase the necessary amount of trays per their unique demands for maintaining the litter box. The system is utilized for maintaining the litter box by separating soiled waste from the non-soiled (clean) litter by lifting a topmost sifting tray so that clean litter passes downwardly through openings and enters onto (into) the next, now topmost layer. The removed upper-most tray containing soiled waste then may be placed into a bag, for example a biodegradable bag, for an eco-friendly disposal. In embodiments, a user may clean trays such a brushing them clean and return the brush cleaned trays to the system in lieu of disposing of trays after use.

[0121] In one embodiment, the system is designed to be a subscription, where a user orders the product online and it is shipped and delivered to the user's choice of location. Shipping directly to a user advantageously eliminates hauling heavy litter home from the store. Litter may be preloaded in the kit, advantageously eliminating the strain and hassle of lifting a heavy bag of litter and pouring it into the tray. In one embodiment, the litter ingredients may be 100% biodegradable. In an embodiment, the litter may be a hybrid blend of the most popular sodium bentonite (clumping) clay blended with a clumping plant based or wood based granule, or bentonite clay or fillers earth or diatomaceous earth, or a blend of any of the aforementioned or any other type of litter. In embodiments, the litter material may be customized for the user's and pet's preferences.

[0122] Components of the litter tray system, such as a high shield, base tray, and one or more sifting trays, may be formed from recycled cardboard, paper pulp, bagasse, bamboo, wheat straw, or any other biodegradable or plant based pulp material. In embodiments, components are shaped by applying slurry or pulp around a form and then drying. In embodiments, forms may define any openings in individual components of the system. In embodiments, the slurry or pulp dries into unitary components and desired openings are then cut into the component. In embodiments, components of the system are pressed or molded. Methods of molding pulp material into forms is known, see for example U.S. Pat. Nos. 3,046,187, 3,325,349, 3,243,096, 488,517, 5,656,135, and 1,551,257. All of which are incorporated herein for all purposes.

[0123] In embodiments, components of the system may be polymers or metallic. It is within the scope of this disclosure to have any combination of components formed of different materials. For example, a litter tray system could include a metallic base tray, one or more pulp based sifting trays, and a polymer high shield. In another example, a litter tray system could include a first polymer base tray, a pulp based base tray, one or more pulp based sifting trays, and a pulp based high shield. Additional structural ribs may be incorporated into the components for support in embodiments. Further, embodiments may include additional cooperating detents and indents, for example on walls or lips, to further prevent slippage or movement of components in either shipping or use configurations. It will be appreciated that some pulp materials have an amount of plasticity such that they may be flexible or otherwise deformable. According, some portions of the trays of a litter box system may readily conform to one another. For example, the circumferential lip of a top most sifting tray might readily conform the circumferential lip an adjacent sifting tray immediately below. As noted above, ribs and the like can add rigidity to pulp structures. In addition, buildup of pulp in key areas, such as along curved portions, may increase rigidity. Pulp structures may also become more rigid as they are stacked. For example, the sidewalls of two more stacked trays may be more rigid than the sidewall of an individual tray.

[0124] Although specific examples have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement calculated to achieve the same purpose could be substituted for the specific examples shown. This application is intended to cover adaptations or variations of the present subject matter. Therefore, it is intended that the invention be defined by the attached claims and their legal equivalents, as well as the following illustrative aspects. The above described aspects embodiments of the invention are merely descriptive of its principles and are not to be considered limiting. Further modifications of the invention herein disclosed will occur to those skilled in the respective arts and all such modifications are deemed to be within the scope of the invention.