Patent ID: 6944891

Claim:
In a toilet of the type having a trapway, the trapway extending between a bowl opening and an outlet, the trapway having a curved water dam region extending from the bowl opening to above the bowl opening to a down leg, the down leg being linked to an out leg at a lower end of the down leg, the out leg communicating with the outlet, the improvement comprising: the trapway having an air dam cavity along an upper wall of the out leg causing flow passing through the trapway to separate from an interior surface of the trapway at a leading edge of the air dam; wherein the trapway further comprises an essentially horizontal baffle extending forward from a rear wall of the down leg adjacent a lower portion of the down leg; and wherein the trapway has a circular cross-section throughout the curved water dam region which does not vary more than 5 percent in diameter throughout the portion of the trapway that is the curved water dam.