Hopper bottom unit

In a hopper for discharging fluent material, said hopper having an outlet port, an opening at the bottom of said hopper, said opening being defined by a lip located in a plane that is slanted at an angle with respect to the horizontal, the lowest point of said lip being located subjacent to said outlet port and the highest point of said lip being located across said opening opposite and spaced from said outlet port, wherein the improvement comprises a discharge unit comprising:

• a casing with an integral attaching flange on a circumferential edge thereof;
• means for attaching said edge of said casing to said lip circumjacent said opening such that said discharge unit is attached to said hopper independently of and spaced from said outlet port;
• a planar plate mounted within said casing and tilted at said angle and sloping toward said outlet port;
• a plurality of spaced elongated, longitudinally curved projections mounted on the top surface of said plate so as to define a riffle-like pattern thereon, each of said projections including a ramp ascending toward said outlet port from said plate and a rear leg that is sloped upwardly from said plate away from said outlet port such that said projections are triangular in transverse cross-section;
• and
• a vibration producer, means connecting said producer to said plate and projections to cause said plate and projections to pulsate thereby assisting the movement of fluent material in said hopper toward said outlet port.