Patent ID: 8201280

Claim:
A device to protect waste water lines, comprising: a pipe wall defining an upstream end, a downstream end, an inside diameter and a longitudinal axis, and having an inner surface defining a hollow interior having an upper half and a lower half; first and second spikes projecting inwardly from first and second points on the inner surface of the pipe wall, said spikes extending from first and second bases at said first and second points to first and second free tips, respectively, each of said spikes projecting toward the upstream end of said pipe for its entire length from the respective base to the respective tip, with the upstream angle from the base of each of said spikes at the inner surface of the pipe wall to the tip being at least twenty degrees, with the angle defined between first and second radii of the pipe extending through the tips of the first and second spikes to the bases of those first and second spikes, respectively, being between ninety degrees and one-hundred thirty degrees, and with the spikes extending inwardly from the inner surface of the pipe wall a distance that is from 20% to 40% of the inside diameter, with said first and second spikes lying entirely in said upper half and with the lower half being free and open to permit the free flow of wastewater; wherein said pipe wall is a structurally independent member that can be connected downstream of an outlet pipe which projects rearwardly from a toilet and extends through the wall of a building.