Abstract: An apparatus for non-interactive, dry powder development of electrostatic Images composed of solid areas and fine lines areas on an imageable surface including a housing containing developer material; a first magnetic roll, spaced a first predefined distance from the image, for transporting the developer material from the housing to develop solid areas of the image, the magnetic roll including an magnetic core and a cylindrical sleeve enclosing and rotating about the magnetic core; and a second magnetic roll, spaced a second predefined distance from the image, for transporting the developer material from the housing to develop fine line areas of the image, the magnetic roll including an magnetic core and a cylindrical sleeve enclosing and rotating about the magnetic core.

Abstract: A xerographic reproduction machine for producing toner particle copy images of original images on sheet substrates includes a machine frame; a movable image bearing member mounted within and to the frame, the image bearing member having an image bearing surface defining a path of movement thereof. The xerographic reproduction machine also includes xerographic imaging elements mounted at various distributed locations along the path of movement for forming toner particle copy images of original images on the image bearing surface; devices for transferring the toner particle copy images onto sheet substrates for fusing; and an impulse air ejector cleaning system for intermittently purging and cleaning particulate dirt from sensitive elements among the electrostatographic imaging elements.

Abstract: A preconditioning process and dual electrostatic brush cleaning apparatus for reducing adhesion of toner particles on the photoreceptor surface such that cleaning of the photoreceptor is enhanced. Preconditioning of the brush and/or the photoreceptor in the cleaning apparatus allows for cleaning of dual polarity toners, CAD toners and DAD toners. The preconditioning of the brush does not need replenishing once the print operation begins due to the electrostatics that maintain a constant predetermined level of toner in the brush.

Abstract: An electrostatographic reproduction machine that includes an image bearing member means for forming a latent image having image areas and background areas; at least a development housing containing charged carrier beads, charged fragments of the charged carrier beads which undesirably cause image deletions, and charged toner particles for developing image areas to form a toner image; means for transferring the toner image to a sheet of paper, and means for fusing the toner image to the sheet of paper. Importantly the reproduction machine includes a method and control system for reducing halftone image deletions in future halftone images.

Abstract: An apparatus and method for cleaning charged triboelectric negative toner residual particles from the photoreceptor surface. A positive bias is applied to two electrostatic brushes in the dual cleaning system or to a single electrostatic brush. The rotational speed of the single positive brush is increased, over that of the individual brushes in a dual brush cleaner, to clean charged triboelectric negative toner particles.

Abstract: A particulate image developer material mixing system for a reproduction apparatus, with a rotatably driven helical mixing coil in a developer material sump for mixing the developer material in the sump, and with a system for holding the rotatably driven helical mixing coil in the sump, and a system for anti-bridging of the developer material by agitating the developer material in the sump by agitating the mixing coil; including a smoothly rounded rod substantially extending inside of the helical mixing coil with a smoothly enlarged diameter end portion outwardly radiused to operatively intermediately engage the mixing coil so that as the helical mixing coil is rotatably driven at least one coil thereof is periodically partially detained and deformed on the smoothly enlarged diameter end portion and then periodically released automatically after a further rotation, so as to provide a periodic anti-bridging agitation of the developer materials, at a desired frequency, and the free end of the helical mixing coil

Abstract: An apparatus which cleans a moving imaging surface with a cleaning blade and automatically detects a failure of the cleaning blade. A failure sensing mechanism detects the cleaning blade failure and activates a blade indexing mechanism. The indexing mechanism removes the failed cleaning blade and positions a new cleaning blade in a wiping or doctoring mode frictional contact with the imaging surface for cleaning. A brush positioned upstream of the cleaning blade, in the direction of movement of the imaging surface, disturbs the particles thereon.

Abstract: A cleaning brush electrically biased with an alternating current removes discharged particles from an imaging surface. The particles on the imaging surface are discharged by a corona generating device. A second cleaning device including an insulative brush, a conductive brush or a blade, located upstream of the first mentioned brush, in the direction of movement of the imaging surface, further removes redeposited particles therefrom.