Material feed system for selectively delivering lightweight, friable mesh fibers

Abstract

A material feed system and method for conveying a metered quantity of lightweight, friable mesh fibers without minimal damage to the mesh fibers to concrete and like materials mixing tank. The material feed system including a hopper with a spiral fiber guide near the discharge and flexible blades for clearing fibers from the upper and lower surfaces of the spiral fiber guide. A drive assembly is included for rotating the hopper at a rotation rate adequate to move and agitate the mesh fibers to facilitate flow of the mesh fibers first outward against the side walls of the bin and then rapidly downward through the bin being guided by the spiral fiber guide. To convey the fibers from the hopper outlet to the mixing tank with minimal damage, the material feed system includes a vacuum conveyor assembly comprising an air inlet and a vacuum conveyor conduit in which a vacuum is created by a venturi aspirator and blower to draw the fibers from the hopper outlet through the vacuum conveyor conduit in a compact state to minimize damage to fibrils of the mesh fibers. To meter the fibers fed into the hopper, a metered feed assembly is used that includes a feed drum with an inlet-outlet opening, a device for slowly rotating the feed drum, and a feed bin that stores inputted mesh fibers. When the feed drum is rotated, fibers from the feed bin enter the feed drum when the inlet-outlet opening is directed upward, and the fibers are dispensed to the hopper when the inlet-outlet opening is directed downward.