Lift-assisted litter box system

• US 8,230,810 B2
• Filed: 04/22/2010
• Issued: 07/31/2012
• Est. Priority Date: 04/22/2010
• Status: Expired due to Fees

• Current Assignee: Craig Mynatt
• Original Assignee: Craig Mynatt
• Inventors: Mynatt, Craig, Larson, Kenneth Michael
• Primary Examiner(s): Nguyen, Son T
• Assistant Examiner(s): ALKER, KATHLEEN IWASAKI
• Application Number:
  US12/765,137
• Publication Number:
  US 20110259275A1
• Time in Patent Office: 831 Days
• Field of Search: 119/161, 119/163, 119/165, 119/166, 119/168, 108/99, 108/100, 108/108, 108/94, 108/95, 108/138, 312/408, 312/351, 312/325
• US Class Current: 119/168
• CPC Class Codes: A01K 1/0114 Litter boxes with screens for separating excrement from litter

Abstract

A litter box device for use by pets. The device includes at least two litter boxes arranged as stacked drawers held in a housing. The upper drawer is accessible to a pet through an entry to the housing. The bottom of each drawer has a screen and a slidably removable drawer bottom. Removal of the slidably removable drawer bottom allows the contents of the drawer to pass into the underlying drawer. After pets excrete waste into the litter in the top box, the loose litter is separated from the waste clumps by sliding the removable drawer bottom from the top drawer, allowing loose litter granules to flow down through a screened opening into the underlying drawer. The top drawer will retain the waste clumps on its screen within the upper drawer, the screen positioned proximate to the slidably removable drawer bottom. The waste clumps may then be removed from the drawer and screen. The lower drawer containing the filtered litter can be guided up into the top position. A lift assisting mechanism allows the lower drawer to be lifted into the upper drawer position without the operator having to bear the full weight of the litter-filled drawer. After the emptied drawer is placed in the vacant lower drawer position the apparatus is ready for pet use again.

Claims

1. A device for holding pet litter comprising:

a housing having an open front face section;

a first drawer slidably mounted to be moved with first drawer supports moving on top horizontal runners and bottom horizontal runners in and out of said open front face section to an upper position and a lower position respectively, said first drawer including a screen proximate to a first drawer bottom and an at least partially retractable drawer bottom;

a second drawer slidably mounted to be moved with second drawer supports moving on the top horizontal runners or the bottom horizontal runners in and out of said open front face section, said second drawer including a screen proximate to a second drawer bottom and an at least partially retractable drawer bottom; and

a runner ramp system within said housing, said runner ramp system connecting the bottom horizontal runners to the top horizontal runners and having a direction-changing midway point that is at a forwardmost point towards the open front face section;

wherein when said first or said second drawer is in the upper position, a first drawer open top or a second drawer open top, respectively, is accessible to a pet.

2. The device of claim 1, wherein said housing includes a lower section and an upper section, said lower section holding said first drawer and said second drawer.

3. The device of claim 1, wherein said housing is divided into a pet entrance section and a pet litter drawer section, said pet entrance section and pet litter drawer section divided by a partial wall in an upper section of the housing.

4. The device of claim 3, wherein said pet entrance section includes a ramp extending from below an upper drawer bottom level to above an upper drawer bottom level.

5. The device of claim 1, wherein said first drawer and said second drawer each include a respective outward sloping back drawer wall having side sections angled and shaped to form a clump channel.

6. The device of claim 1, wherein at least one of said first drawer and said second drawer includes a spring or a gasket acting as a bottom sealing mechanism which exerts a force on a respective drawer bottom.

7. The device of claim 1, further including:

a first handle on the first drawer;

a second handle on the second drawer;

a first drawer bottom release latch on said first drawer bottom; and

a second drawer bottom release latch on said second drawer bottom, wherein each release latch may secure to the first or second handle respectively and be locked to prevent movement of an associated drawer bottom or released to allow retraction movement of an associated drawer bottom.

8. The device of claim 1, wherein the runner ramp system within said housing includes pairs of pivoting guides, said pivoting guides pivoting upward to allow the first and second drawer supports to move past the pivoting guides, and pivoting downward to form surfaces over which the first and second drawer supports may move.

9. The device of claim 8, wherein said pivoting guides include end toes and said runner ramp system includes toe holes into which said end toes fit, thereby securing said pivoting guides into place.

10. The device of claim 8, wherein said runner ramp system includes a head space above pivoting guide end toes, said head space proving sufficient clearance for the first and second drawer supports to pass through the runner ramp system.

11. The device of claim 8 wherein the pairs of pivoting guides include a pair of midway pivoting guides having respective pivot points above and rearward of the direction-changing midway point.

12. The device of claim 11 wherein at least one of the midway pivoting guides has a respective toe hole proximate to the midway point.

13. The device of claim 1, wherein said housing includes a ramp extending from below an upper drawer bottom level to above an upper drawer bottom level.

14. The device of claim 1 wherein the runner ramp system includes a drawer resting station at the direction-changing midway point.

15. A litter box system comprising:

two drawers each having a respective screen and a respective retractable bottom; and

a housing having;

top horizontal runners;

bottom horizontal runners;

inclined runners connected to the top horizontal runners and the bottom horizontal runners as a sideways V-shaped rampway having a midway point defining a single switchback at a forwardmost point towards a front of the housing; and

movable guides admitting each of the two drawers from the bottom horizontal runners to the inclined runners, thence to the midway point of the inclined runners and from the inclined runners to the top horizontal runners, and preventing admittance to either of the two drawers from the top horizontal runners to the inclined runners nor and to the bottom horizontal runners except by a removal of the either of the two drawers from the housing and a reinsertion of the either of the two drawers to the housing at the bottom horizontal runners.

16. The litter box system of claim 15 wherein a one of the two drawers is confined by the bottom horizontal runners while being pushed from outside of the housing to a lower position in the housing with a further one of the two drawers in an upper position in the housing.

17. The litter box system of claim 15 wherein the top and bottom horizontal runners, the inclined runners and the movable guides are arranged so that a one of the two drawers can be sequentially:

pushed from outside of the housing to an upper position in the housing, guided by the top horizontal runners;

pulled out of the housing, guided by the top horizontal runners;

pushed from outside of the housing to a lower position in the housing, guided by the bottom horizontal runners;

pulled up and partially out of the housing to the midway point, while being guided by the movable guides from the lower position on to the inclined runners and thereupon to the midway point, whereupon about half of the one of the two drawers remains in the housing; and

pushed up and in to the housing guided by the inclined runners from the midway point to the upper position.

18. The litter box system of claim 15 wherein the movable guides include pivoting guides at transition points between the bottom horizontal runners and the inclined runners, at the midway point, and between the inclined runners and the top horizontal runners.

19. The litter box system of claim 18 wherein the pivoting guides include at least one pivoting guide at the midway point having a respective pivot point above and rearward of the midway point.

20. The litter box system of claim 15 wherein the inclined runners include a drawer resting station at which either of the two drawers can rest at the midway point.