Abstract:
Apparatus and method to detect and measure, in a non-image area on a toner-image-bearing member, a low coverage of toner particles relating to a background coverage of toner particles in an image frame, and in particular, to detect and measure by an optical detector a low toner coverage in excess of a threshold coverage or a pre-selected coverage and thereby produce a signal, e.g., a process control signal. Such a process control signal can be used to adjust the operating parameters of a process in a subsystem, such as a toning process or a photoexposure process. In preferred embodiments, synchronous detection is used to extract a signal having a magnitude proportional to the low toner coverage representative of the background coverage of toner particles.
Abstract:
An apparatus and method for dispensing toner in an electrostatographic printer includes apparatus for drawing ambient air in a vertical direction, preferably upwards, through a relatively large toner container. The air-flow is sufficient to fluidize the toner in the toner container and thereby prevent compaction. Such fluidization is optionally supplemented by the action of an auger or propeller mechanism mounted within the toner container. During rotation of the auger/propeller, the toner is lifted and thereby further prevents toner compaction.
Abstract:
A non-contact optical sheet size and/or position detection system for detecting the position of at least one edge of an outside (top or bottom) document sheet stacked in a sheet stacking tray in which thin document sheets of different sizes and/or positions are stacked on top of one another; with an illumination source for illuminating the potential sheet edge areas at an angle generating detectable sheet edge shadows, and an optical detection system remotely detecting the edge shadow positions to provide sheet edge location information to a control system for the imaging or offsetting of the sheet. In a document feeder for sequentially feeding a top or bottom sheet to be imaged, the detection system may be responsive only to a moving sheet edge shadow to determine the size of the sheet being fed to be imaged relative to other sheets in the stack irrespective of intermixed different sizes of sheets in the stack. For a bottom feeder the detection may be through an elongate aperture in the tray. For an output stacking system with a system for offsetting alternately printed sets of sheets in a stacking tray the detected edge shadow(s) of the top sheet may be used to control the offsetting.
Abstract:
To remove ferromagnetic carrier beads from the surface of a photoreceptor leaving a development station in an electrophotographic machine, the carrier beads are magnetically attracted to the surfaced of an elongated, rotating cylinder. The cylinder surface is provided with a raised spiral thread to create a material conveying auger operating to axially convey the attracted beads to a cylinder end portion beyond a side edge of the photoreceptor, where the carrier beads fall into a sump.
Abstract:
An apparatus in which an electrostatic latent image recorded on a photoconductive member is developed with toner. A donor roll, spaced from the photoconductive member, transports toner to a development zone adjacent the photoconductive member. An electrode member is positioned in the development zone between the photoconductive member and the donor roll. The electrode member is electrically biased to detach toner from the donor roll so as to form a toner powder cloud in the space between the electrode member and the photoconductive member. A unitary magnetic roll is located in the housing to transport developer material to a reload zone where toner particles are attracted from magnetic carrier granules to the donor roll. The parameters are selected to optimize reload and suppress strobe lines.
Abstract:
An apparatus that monitors the quality of copies reproduced by a printing machine. A signal of an image to be reproduced by the printing machine is transmitted to an electronic subsystem. The electronic subsystem converts the signal to a reference bitmap and transmits the reference bitmap to a raster output scanner in the printing machine. The printing machine reproduces the image on a copy sheet. The image reproduced on the copy sheet is scanned by a raster input scanner and a scanned bitmap generated. A comparison is made between the scanned bitmap and the reference bitmap to determine if the image reproduced on the copy sheet is at an acceptable quality level.
Abstract:
An apparatus in which developer material is transported to the latent image. Toner particles are attracted from the carrier granules of the developer material to the latent image. The developer material is in a chamber of a housing and additional toner particles are supplied thereto. A portion of the toner particles are removed from the chamber of the housing. The average size of the toner particles removed from the housing chamber is greater than the average size of the toner particles remaining in the housing chamber.
Abstract:
An apparatus which controls the parameters in a processing station of an electrophotographic printing machine having a photoconductive member. A test patch having a half tone image is recorded on the photoconductive member. The test patch is developed with developer material to form a developed half tone image on the photoconductive member. In response to the average density of the developed half tone image on the photoconductive member, the parameters of the processing station are regulated.
Abstract:
Apparatus and method for separating and recovering separately toner particles of one matchable characteristic different color toner contained in a mixture of a plurality of such different color toners. The apparatus and method include a holder for holding a quantity of the mixture of a plurality of such different color toners, and a selected particular type of carrier beads characteristically matching, and being more likely to charge, attract and triboelectrically bind with, toner particles of a matching color toner in the mixture of the different color toners than with toner particles of any other color toner therein. The apparatus and method also include a blending device for forming, in the holder an admixture of a quantity of the mixture of the different color toners and a quantity of the selected particular type of carrier beads such that the admixture has a toner coated carrier phase and a loose toner particles phase, and such that the toner coated carrier phase consists of the selected particular type of carrier beads coated with toner particles of the matching one color toner of the different color toners of the admixture. The apparatus and method further include separating mechanisms for separating the toner coated phase from the loose toner particles phase, and a recovery mechanism for separating and removing, from the coated selected particular type of carrier beads of the toner coated phase, the toner particles of the matching one color toner.
Abstract:
A method and apparatus for identifying surface relief features of a substrate processed in a printing machine, and adjusting the machine parameters as a function thereof, before the substrate is processed through the machine. The apparatus includes a light source positioned adjacent to the substrate surface. A light sensing device, in a light receiving relationship with the substrate surface, detects light reflected from the substrate surface. A signal is generated indicative of sensed light intensity with a first magnitude range indicating ridges and a second magnitude range indicating depressions. Control circuitry, electrically connected to the light sensing device, receives the signals of ridges and depressions, and discriminates between them to generate a set of signals indicating surface relief features of the substrate.