US Patent 7740401 Food mixing machine and agitator therefor

A food mixer (10) includes a rotatable shaft (18) which is connected to the shaft (21) of an agitator (20). The agitator (20) includes an upper disk (23) attached to the shaft (21) and a lower disk (28). Slat walls (27, 29) extend from the upper disk (23) to the lower disk (22) and slat walls (27, 29) are curved so as to together forming a parabolic ring. A central blade (33) extends from the upper disk (23) to the lower disk (28) between the slat walls (27, 29). Both the upper and lower disks (23, 28) are circular and are curved upwardly in one direction and curved downwardly in a direction transverse to the one direction.