Particulate material distributor, having a tensioned flexible cover for clean-out aperture below hopper

A hopper, comprising:

• wall means defining a box having two opposite end walls, a front wall, a bottom wall and a rear wall, said box enclosing in a lower portion thereof a dispensing mechanism which is constructed and arranged to direct fluent material, when contained in said hopper, towards means defining an outlet aperture from said box through said wall means in said lower portion;
• said two opposite end walls having respective front edges which are convexly curved as seen in side elevation
• a normally-closed clean-out aperture being defined between said curved front edges of said two opposite end walls, and between an upper edge provided on said bottom wall meanss a lower edge provided on said bottom wall means, so that said curved front edges, said upper edge and said lower edge define the perimeter of said aperture;
• a normally-closed, openable cover means for said clean-out aperture, said cover means comprising at least one sheet of deformably flexible inert non-metallic material secured along one edge thereof, to said box along one of said upper edge and said loer edge of said aperture;
• and
• means for releasably securing each said sheet of said cover means to said box along the other of said lower edge and said upper edge with said cover means tensioned into wrapped sealing engagement with both said curved front edges of said end walls, thereby normally closing said clean-out aperture.