Abstract: A method of calibrating a multi-color electrophotographic machine having an image bearing surface includes forming toner patches of cyan, magenta, and yellow solid areas individually and in superimposed combination to form a series of single layer and multi-layer test patches. Light is emitted onto these single and multi-layer test patches. The amount of light that is reflected off of each test patch is measured. Light is also emitted onto a bare section of the image-bearing surface. The bare section has substantially no toner thereon. An amount of light that is reflected off of the bare section is measured. The step of measuring an amount of light reflected off single layer solid area test patches is repeated for a series of laser power and developer bias conditions. A laser power and/or a developer bias is adjusted dependent upon each of the three measuring steps.

Abstract: A waste toner removal device for transporting toner from a photoconductive drum within an image-forming apparatus. The invention includes a waste toner reservoir having outer walls forming an interior chamber for housing toner removed from the photoconductive drum. An opening is positioned within the outer walls into the interior chamber forming an upper chamber section extending above the opening and a lower chamber section extending below the opening. An auger extends along the photoconductive drum and unobstructed into the opening of the waste toner reservoir. The auger includes helical blades extending outward for moving the toner from the photoconductive drum into the waste toner reservoir. A pumping cylinder having a generally cylindrical shape extends around the auger adjacent to the waste toner reservoir.

Abstract: An electrophotographic image forming apparatus includes a photoconductive drum and a transfer roll-positioned adjacent to and defining a nip with the drum. An image substrate travels through the nip in an advance direction. A toner cartridge assembly is positioned in association with the drum and above the image substrate. A pre-transfer erase assembly having a light emitting outlet is positioned between the toner cartridge assembly and the image substrate. The light emitting outlet is directed toward the drum.

Abstract: A toner cartridge has a comminuator that prevents the buildup of toner behind the doctor blade that meters the toner delivered to the developer roller for later image development and printing. The comminuator is mounted to, and for movement with, an agitator adjacent to an exit port of the toner hopper. A paddle that rotates within the toner hopper contacts the agitator and generates joint movement of the agitator and comminuator. The comminuator comprises a plurality of spaced blades held by a coupler mounted to the agitator. Alternatively, the comminuator comprises a wire mounted in opposing connectors mounted to the agitator.

Abstract: A charge roller has a steel shaft and conductive outer cylindrical body which is formed by curing with heat a blend comprised of epichlorohydrin rubber, mineral-oil-free zinc oxide dispersion, stearic acid as a lubricant, accelerators and a sulfur donor. The roller has a long useful life and does not express oil while inactive.

Abstract: A flexible doctor blade having a radiused surface or nub for contacting a developer roll. The blade geometry which includes a cantilevered support for the nub provides lower torque in the developer, compliance to compensate for developer imperfections, and less tendency for streaking due to toner packing and filming.

Abstract: A toner cartridge (1) has a cylindrical toner hopper (61) with a rear wall (61a) defining an output opening well above the lower part of the hopper. A paddle (63) is rotated in the hopper. The exit surface (61aaa) declines downward to form a chamber for the toner adder roller (45) and developer roller (43). This configuration discourages toner from returning to the hopper after it has been electrically charged.To improve movement of toner past the opening an agitator bar (65) extends across the cartridge near the exit surface. The bar is pivoted at both ends and has a portion (65a) which extends into the path of the paddle. As the paddle rotates, it moves the agitator upward until the curved paths of the two members reach separation, at which time the bar drops by gravity. The bar jars toner loose and eliminates jams of toner. The flat surface of the bar, when it has been moved up, partially blocks the exit opening, which desirably limits toner flow.