Sanitary drain system, method, and fittings therefor

Claim 1

AN AERATING FITTING FOR CONNECTING A LATERAL SANITARY DRIAN PIPE TO A VERTICAL DRAIN STACK COMPRISING A BODY PORTION HAVING SIDE WALLS DEFINING A MIXING CHAMBER, THE UPPER PORTION OF SAID MIXING CHAMBER HAVING A WIDTH AT LEAST TWICE AS GREAT AS THE LOWER PORTION THEREOF, SAID BODY PORTION HAVING A DRAIN STACK INLET CONNECTION AT ITS UPPER END, A DRAIN STACK OUTLET CONNECTION AT ITS LOWER END, AND A LATERAL DRAIN INLET CONNECTIN, SAID STACK INLET CONNECTION AND SAID LATERAL DRAIN INLET CONNECTION COMMUNICATING SAID BY SIDE WITH THE UPPER PORTION OF THE MIXING CHAMBER AND SAID STACK OUTLET COMMUNICATING WITH THE LOWER PORTION OF THE MIXING CHAMBER, A SIDE WALL OF THE MIXING CHAMBER BETWEEN THE LATERAL DRAIN INLET CONNECTION AND THE STACK OUTLET CONNECTION BEING VERTICAL AND PARALLEL TO THE AXIS OF SAID OUTLET CONNECTION AND THE OPPOSITE SIDE ALL BEING DIVERGENT UPWARDLY AND AWAY FROM SAID AXIS, A GUIDE PLATE WITHIN THE FITTING ABOVE THE MIXING CHAMBER IN POSITION TO DIRECT SUBSTANTIALLY THE ENTIRE VOLUME OF LIQUID FLOWING INTO THE FITTING THROUGH THE LATERAL INLET CONNECTION DOWNWARDLY IN A STRAIGHT LINE VERTICAL PATH THROUGH THE MIXING CHAMBER TO THE STACK OUTLET CONNECTION, THE STACK INLET CONNECTION COMMUNICATING WITH THE UPPER PORTION OF THE MIXING CHAMBER ON THE SIDE OF SAID GUIDE PLATE OPPOSITE THE LATERAL DRAIN INLET CONNECTION AND ON AN AXIS DISPLACED LATERALLY FROM THE AXIS OF THE STACK OUTLET CONNECTION BY AT LEAST THE DIAMETER OF SAID OUTLET, WHEREBY THERE IS NO STRAIGHT LINE PATH FOR THE FLOW OF FLUID THROUGH THE MIXING CHAMBER FROM THE STACK INLET TO THE STACK OUTLET.