Samsung Electronics Co., Ltd.

Other

Imation Corporation

William D Edwards

Truman Frank Kellie

Charles W Simpson

Hsin Hsin Chou

Robert E Brenner

Steven C Jensen

Michael R Bury

Brian P Teschendorf

Edward J Moe

Vicki K Edwards

Andrew J McClaren

This invention relates to a developing unit for maintaining constant density in an electrophotographic imaging process. The developing unit has a developer roll, wherein the developer roll provides a surface and a first voltage is applied to the developer roll; a skive device, wherein the skive device is positioned in contact with the developer roll and a second voltage is applied to the skive device; a cleaning device for the developer roll, wherein the cleaning device is in contact with the developer roll; and an ink container, wherein the developer roll and the cleaning device are inside the ink container. It is preferred that a current measuring device is present to measure current flow between skive device and the developer, or a voltage meter is present to measure a voltage across a known resistor that is in series with the power supply to the skive device.

Developing unit and density control method in electrophotography

A process and apparatus prints images. The process provides an imaging surface; an array of styli opposed to the imaging surface; and a flow of liquid ink containing charged ink particles in the ink between the imaging surface and the array of styli. A voltage bias is established between at least one stylus in the array of styli and the imaging surface. The voltage bias plates at least some charged ink particles onto the imaging surface in response to the voltage bias.

Electrophoretic stylus array printing with liquid ink

Linear spot velocity or position variations are measured in a scanning system by a process and apparatus. The process comprises providing at least two radiation detectors that can move in tandem across a scan line, the two radiation detectors being spaced apart by a distance d; positioning the at least two radiation detectors at a first point on the scan line; scanning the at least two radiation detectors with scanning radiation and recording the position of the two detectors along the scan line and the time taken for the scanning radiation to scan from a first of the at least two radiation detectors to a second of the at least two radiation detectors while the at least two radiation detectors are positioned at the first point; moving the at least two radiation detectors to a second point on the scan line maintaining the distance d between the at least two radiation detectors; and again scanning the at least two radiation detectors with scanning radiation and recording the position of the two detectors along the scan line and the time taken for the scanning radiation to scan from a first of the at least two radiation detectors to a second of the at least two radiation detectors while the at least two radiation detectors are positioned at the second point.

Scanner linearity tester

A method measures the conductivity (&#x3c3;) of a liquid or paste electrophotographic toner by providing two parallel plane conductive plates with a uniform separation (d) between the plates to form a space between the plates; filling the space between the plates with liquid or paste electrophotographic toner; applying an alternating current voltage of at least 100V between the plates across the liquid or paste toner; measuring as data the current passing through an external component into the plates; adjusting the data to remove current contributions attributable to impurity ions; sending adjusted data to a processor; and determining the conductivity from the adjusted data.

System and method for measuring charge/mass and liquid toner conductivty contemporaneously

A method of maintaining a surface charge on a photoreceptor within a predetermined voltage range is provided, comprising the steps of providing a charging device adjacent to a surface of the photoreceptor, determining a reference voltage to be applied by the charging device to the photoreceptor surface to establish a first photoreceptor surface voltage, and applying the reference voltage to the surface of the moving photoreceptor with the charging device while measuring a first photoreceptor current. The method further comprises comparing the first photoreceptor current to predetermined characteristics of the photoreceptor to calculate a first output value, comparing the first output value to predetermined characteristics of the photoreceptor and calculating a first correction voltage, and applying the first correction voltage to the photoreceptor surface with the charging device to obtain a surface voltage on the photoreceptor that is within the predetermined operational voltage range.

Closed loop control of photoreceptor surface voltage for electrophotographic processes

An optical transceiver measures optical density of a toned image. The optical transceiver comprises:

Optical transceiver and method for image density measurement

A developing unit maintains constant density in an electrophotographic imaging process. The developing unit has:

A fusing apparatus for fixing images made from a liquid toner onto a substrate using an electrophotographic process, the apparatus including a first fusing station having first and second prefusing rollers, the second prefusing roller contacting the first prefusing roller to create a first nip area, wherein at least one of the prefusing rollers is heated to a temperature that provides a prefusing temperature within the first nip area, and a second fusing station spaced from the first fusing station and having first and second final fusing rollers, the second final fusing roller contacting the first final fusing roller to create a second nip area, wherein at least one of the final fusing rollers is heated to a temperature that provides a fusing temperature within the second nip area, wherein the fusing temperature of the second nip area is higher than the prefusing temperature of the first nip area.

Fuser system and method for electophotography including multiple fusing stations

A fusing apparatus for fixing images made from a liquid toner onto a substrate using an electrophotographic process, the apparatus including a prefusing roller, a backup roller positioned to create a first nip area between the prefusing roller and the backup roller, and a fusing roller positioned to create a second nip area between the fusing roller and the backup roller, wherein at least one of the prefusing roller and the backup roller is heated to a temperature that provides a prefusing temperature within the first nip area, and wherein at least one of the fusing roller and the backup roller is heated to a temperature that provides a fusing temperature in the second nip area that is different than the prefusing temperature of the first nip area.

Fusing apparatus and method for liquid toner electrophotography using multiple stations having different prefusing and fusing temperatures

A testing procedure and method is provided for assessing the quality or acceptability of performance of individual liquid ink electrostatic toners on individual receptor surfaces. An approximately standard drop of the individual liquid toner is placed on the receptor to be tested. The drop is pressed onto the receptor and spread on the surface of the receptor (preferably before the drop has had time to partially evaporate or to have the liquid in the drop absorb or naturally spread on the receptor surface) under controlled conditions. The characteristics of the spread drop on the receptor surface are measured, and the characteristics are compared to parameters defining the characteristics expected from a liquid toner that define acceptable performance between toner and receptor. In this manner the relative performance of individual toners on individual receptor surfaces can be evaluated independent of electrostatic effects. This can be important, as the electrostatic effects bring another parameter of performance into evaluation of the compatibility of the toner and receptor and can misdirect research for adjusting their compatibility.

Device and method for screening liquid toners and receptors for use with liquid toners in electrophotography

Reduction of seam mark from an endless seamed organophotoreceptor belt

A system for registration of one or more color separation images on a photoconductor belt prevents misregistration that otherwise can occur between different scan lines and between different latent images due to side-to-side movement of the photoconductor belt. The registration system operates to detect movement of the photoconductor belt. Based on the detected movement, the system operates to control modulation of laser beams used to form the latent images to ensure precise registration of the color separation images. As one advantage, the movement of the photoconductor belt can be detected precisely and inexpensively by a photodetector scanned with the same laser beam used for imaging.

System for registration of color separation images on a photoconductor

A method and apparatus for minimizing image banding and for registering multiple image planes of a single image on a receptor drum in electrographic systems. The system for registering multiple image planes of a single image in an electrographic system includes a receptor drum capable of capturing two or more overlaying image planes, an exposure device for forming overlaying image planes on the receptor drum, and at least one developer station transferring a developer to the receptor drum corresponding to each of the overlaying image planes. A measuring device is provided for measuring the rotational position of the receptor drum. A drive mechanism is provided for controlling a motor coupled to the receptor drum by at least one drive belt. A closed loop positioning system is coupled to the measuring device and the drive mechanism. The closed loop positioning system is capable of modulating the angular velocity of the receptor drum to achieve image plane registration of the two or more image planes. The system is capable of achieving image plane registration error of preferably about 100 micrometers or less, more preferably about 50 micrometers or less, and most preferably about 20 micrometers or less. The system is capable of achieving image plane registration error of about .+-.0.5 scan lines or less.

Image plane registration system for electrographic systems

A stir pot is provided including a stirring unit having an outer stir portion with an outer edge. Such outer edge defines a size and shape corresponding to a vertical cross-section of an interior surface of the pot along a diameter thereof. As such, the stirring unit is rotatably situated within the pot and adapted to rotate about central axis of the pot and the outer edge is adapted to scrape the interior surface of pot when rotating. Further provided is a rotating mechanism for selectively rotating the stirring unit.

Automatic stirring and scraping device

A system for registration of color separation images on a photoconductor belt in an imaging system operates to detect a position of an edge of the photoconductor belt. The registration system detects the position with the same laser scanner used for forming latent images on the photoconductor belt. The registration system includes a belt steering control system that steers the photoconductor belt based on the detected position to reduce deviation of the belt from a continuous transport path. The registration system also may include a scan control system that, based on the detected position, controls the modulation of laser beams scanned to form latent images on the photoconductor belt. By controlling belt steering and laser beam scanning, the registration system maintains the image quality of a final multi-color image upon transfer of registered color separation images to an output substrate.

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New Richmond, WI, United States of America

William D Edwards