Patent ID: 7669555

Claim:
A self-cleaning pet litter box assembly configured to separate and remove clumped litter and solid pet waste from clean litter material, comprising: a base; an open-top pet litter container configured to hold litter therein and being mounted for substantially horizontal rotation relative to said base; a conveyor having one end configured to extend into the pet litter container and an opposite exit end, said conveyor comprising a first moving conveyor portion defined by a first plurality of horizontally spaced members and a second moving conveyor portion defined by a second plurality of horizontally spaced members, said first and second conveyor portions moving with reciprocating movement in an out-of-phase relationship and cooperating with each other to incrementally transport clumped litter and solid pet waste away from the litter within the pet litter container in a single direction toward the exit end thereof; a first transverse crankshaft operatively coupled to the first moving conveyor portion and the second moving conveyor portion proximate the exit end; and a second transverse crankshaft operatively coupled to the first moving conveyor portion and the second moving conveyor portion proximate the one end; each of the first and second transverse crankshafts having a fixed axis of rotation, and each of the first and second transverse crankshafts operating so as to rotate in only a single direction to incrementally transport the clumped litter and solid pet waste toward the exit end of the conveyor.