Abstract: Artificial toner consumption is triggered to minimize the incidence of “conditioned” toner when a comparison of the rate of toner consumption to the mechanical activity of the electrophotographic printing device indicates that the toner consumption rate is too low. The artificial toner consumption operation may be achieved through a dummy print operation where an intentionally un-printed image is formed on a photoconductive drum, but the corresponding toner is routed to appropriate waste toner reservoir(s) and the image is not printed on the recording medium. The dummy print toner may be cleaned from the photoconductive drum without being transferred to an intermediate transfer medium and/or may be cleaned from the intermediate transfer medium, both without transferring the toner to the recording medium. The dummy print operation may correspond to a next normally occurring interdocument gap or a dedicated dummy print period inserted between print jobs.

Abstract: Artificial toner consumption is triggered to minimize the incidence of “conditioned” toner when a comparison of the rate of toner consumption to the mechanical activity of the electrophotographic printing device indicates that the toner consumption rate is too low. The artificial toner consumption operation may be achieved though a dummy print operation where an intentionally un-printed image is formed on a photoconductive drum, but the corresponding toner is routed to appropriate waste toner reservoir(s) and the image is not printed on the recording medium. The dummy print toner may be cleaned from the photoconductive drum without being transferred to an intermediate transfer medium and/or may be cleaned from the intermediate transfer medium, both without transferring the toner to the print medium. The dummy print operation may correspond to a next normally occurring interdocument gap or a dedicated dummy print period inserted between print jobs.

Abstract: An apparatus for developing an electrostatic latent image on an imaging member with a liquid developing material, including a liquid developing material applicator, the housing defining an aperture adapted for transporting liquid developing material into contact with the imaging member, the housing further including a planar surface adjacent the aperture for providing a liquid developing material application region in which the liquid developing material can flow freely with the imaging member; a developing roll situated adjacent the liquid developing material applicator and downstream therefrom relative to a path of travel of the imaging member; and a cleaning system, operatively coupled to the liquid developing material applicator, for cleaning residue liquid developer material from the liquid developing material applicator and the developing roll.

Abstract: A development system for developing a latent image so as to compensate for differences in the surface roughness of different types of copy papers receiving the developed image. The development system includes a development unit for each color of toner particles being used within the machine for latent image development. Each development unit has a first developer material supply source, and a second developer material supply source, containing respectively a first developer material and a second developer material of a same color. In order to more fully correct for hue and density differences in images of the same color developed and transferred onto rough versus smooth surface type copy papers, the first developer material importantly contains a higher level of pigmentation than the second developer material.

Abstract: An apparatus which detects a mass of marking material developed on a test patch recorded on a photoconductive surface. The apparatus includes a densitometer, a capacitor sensor and a controller. The densitometer is spaced from and adjacent to the photoconductive surface. The capacitor sensor is also positioned adjacent to the photoconductive surface and spaced therefrom. In operation, the densitometer generates a first signal proportional to the specular component of the total reflectivity of the material deposited on the test patch developed on the photoconductive surface. The capacitor sensor generates a second signal proportional to the mass of material developed on the test patch recorded on the surface. In response to these signals, the controller generates a first control signal as a function of the first signal received from the densitometer in response to the mass of material deposited on the test patch being less than a preselected mass.

Abstract: A method and apparatus for compacting a liquid ink developed image on an image bearing surface in a multicolor electrostatographic printing machine of the type utilizing liquid developing material, particularly an image-on-image type liquid ink multicolor system. The image compacting apparatus includes a biased electrode situated proximate to the image on an image bearing surface, and a liquid applicator for depositing liquid insulating material in a conditioning gap defined by the electrode and the image bearing surface. A high electric potential is applied to the electrode for generating a large electric field in the gap to electrostatically compress toner particles into image areas on the image bearing surface. The liquid insulating material is deposited into the conditioning gap for avoiding the risk of air breakdown as may occur in an electrostatic device of this nature due to the small geometry of the apparatus and the tendency of air ionization in an air gap between electrically biased surfaces.

Abstract: An apparatus for illuminating a photoconductive surface. The apparatus includes a housing defining a chamber and an open end. An imaging device is placed in the housing chamber. The imager transmits light rays through the open end of the housing to the photoconductive surface. An air pump is coupled to the housing. The air pump maintains an outwardly directed flow of air from the open end of the housing so as to move particles away from the open end. Electrically biased electrodes are located between the imaging device and the photoconductive surface. They attract the particles so as to prevent the particles from contaminating the imaging device.

Abstract: In accordance with the present invention, there is provided in a liquid electrophotographic reproduction machine, a development unit for developing latent images on an image bearing member using liquid developer material. The development unit includes a housing defining a liquid developer material holding chamber, and a quantity of liquid developer material contained within the chamber. The quantity of developer material includes carrier liquid and charged toner particles dispersed within the quantity of carrier liquid. The development unit also includes a heating element located inside the quantity of developer material for heating the quantity of developer material. The quantity of developer material when heated has a desired elevated temperature within a range of 50 to 60 degrees centigrade for improved developability without causing toner particle agglomeration.

Abstract: A apparatus for sensing fluid parameters such as optical density, light transmittance, electrical conductivity and/or other characteristics of a fluid, including an emitter adapted to project a light beam and an electrical current and a detector adapted to transmit a first signal in response to receiving the light beam and a second signal in response to receiving the electrical current. A processor determines a set of fluid parameters according to the signals transmitted from the detector. A measured amount of diluent may be added to the fluid to increase light transmittance and/or electrical conductivity so as to enhance sensor operation and sensitivity.

Abstract: System and process for replenishing liquid developer in equipment, such as a printer, whereby the percent of toner solids is maintained at about 0.5 to 4% by weight based on the total weight of liquid developer, the system comprising at least one liquid toner concentrate vessel containing aggregates of thermoplastic resin particles, median particle size (volume weighted) greater than 15 .mu.m, and with 90% of the particles (volume weighted) not less than 30 .mu.m, composed of 50 to 100% by weight of particles and 0 to 50% by weight carrier liquid; a liquid vessel containing carrier liquid, means communicating each of said vessels with a dispersing vessel containing electric field means for breaking apart agglomerates of liquid toner, wherein contents of the liquid toner concentrate vessel and the liquid vessel are supplied thereto and the resin particles are dispersed in the carrier liquid to form particles having a median particle size (volume weighted) of less than 15 .mu.

Abstract: An apparatus for dispersing and/or transporting/migrating particles such as toner that may be prone to agglomeration in a particle dispensing system. Movement and/or vibration of the dispersing and migrating plate member serves to break up, clear and prevent particle agglomerations. Perforations, slits or mesh areas in the upper surface of the plate member can prevent oversize particles/agglomerations from passing through the system, while side walls, fins or disposing the plate member at a angle can channelize the dispersion of the particles contacting the upper surface of the plate member.

Abstract: An electrophotographic printing machine in which an electrostatic latent image is recorded on a moving photoconductive surface by charging the appropriate areas of the surface to predetermined polarities. The latent image is a developed in a development zone with toners of a preselected color and predetermined polarity which are delivered by magnetic bead carriers. A bead removal device is provided adjacent the surface and downstream from the development zone relative to the movement of the surface. The bead removal device magnetically attracts carrier beads off the photoconductive surface. The beads are then deposited in a sump. A vacuum source is also provided for urging beads into the sump from the surface. The bead removal device comprising a sleeve mounted for rotation in a housing, adjacent the surface. The sleeve has a fixed magnet disposed proximate the surface therein and a shunt disposed generally opposite the magnet to define an attraction zone and a release zone.

Abstract: An electrophotographic printing machine in which an electrostatic latent image is recorded on a photoconductive surface by charging the appropriate areas of the surface to predetermined polarities. The latent image is a developed with toners of a preselected color and predetermined polarity by a developer unit. The developer unit includes a bead removal device which magnetically attracts carrier beads off the photoconductive surface and deposits these beads in a sump or reservoir of developer. The bead removal device includes a magnet and magnetic field shapers to enhance the magnetic fields which attract the beads in the zone between the surface and the bead removal device and attenuates the magnetic fields in the zone between the bead removal device and the sump or reservoir to reduce the attraction between the beads and the bead removal device in this zone.

Abstract: An apparatus in which a plurality of developer rollers develop a latent image recorded on a flexible photoconductive member. The photoconductive belt is deflected by the developer material to wrap around at least a portion of the first two developer rollers forming wrapped development zones. The last developer roller may either have the photoconductive belt wrapped about a portion thereof, or the photoconductive belt may remain in an undeflected condition. The developer rollers having the photoconductive belt wrapped thereabout rotate in opposite directions. A blanket of developer material is formed between the last two developer rollers. An apparatus of this type optimizes development of the latent image recorded on the photoconductive member.