Feed hopper assembly for particulate material and printer

Abstract

A feed hopper assembly particularly adapted for feeding particulate material which agglomerates has, end walls and side walls which define a storage chamber having a charging opening for the particulate material, and the side walls converge to form a discharge outlet for dispensing the particulate material. A pulsating diaphragm assembly including, an elastomeric member on the inner wall of the storage chamber, and pump means for causing the elastomeric member to expand the deflate. A transverse shelf or surface adjacent the discharge outlet can be provided for delivering the particulate material to a point of use. Bleed means can also be provided to bleed air from the pulsating diaphragm assembly in the event that pulsations terminate when the diaphragm assembly is in the expanded condition. Also, the combination of the above described feed hopper assembly with an electrostatic printer having a magnetic toning roller, pressure fusing rollers, and means for driving the pressure fusing rollers wherein the transverse shelf acts as a doctor blade for the magnetic toning rollers, and the means for driving the pressure fusing rollers also actuates the pump for pulsing the elastomeric member of the diaphragm assembly to prepare the magnetic toning rollers for the next electrostatic image to be printed.