Browse Prior Art Database

Original Publication Date: 1983-Aug-31
Included in the Prior Art Database: 2004-Apr-04

Publishing Venue

Xerox Disclosure Journal


The figure illustrates in cross-section a toner dispenser with spring loaded walls. The dispenser includes two hopper side walls 10, 12 pivotally mounted at the bottom about pivot supports 14, 16 on each side of a rotatable foam dispensing roll 20 to thereby define a toner hopper for the dispensing roll. Each of the two side walls has a torsion spring 22, 24 supported by a base support 26, 28 to urge each of the side walls upward to the vertical position. When the hopper is filled with toner the weight of the toner is sufficient to hold the hopper side walls down or in the open position. As the toner level drops the load on the walls decreases and the spring force moves the walls toward the vertical position. In this way, the foam dispensing roll remains covered with toner as the toner supply is depleted thereby insuring continued uniform toner dispensing to the developer housing. In addition, this configuration eliminates the need for a toner agitator and allows the initial wall angle to be less than the angle of repose, the angle at which a powder will slide down a surface. Therefore, initially the sides of the hopper may be (level) flat enough that the toner will not "slide" off. As the hopper empties, the angle increases allowing the toner to slide.