Abstract: A grid has a frame body in a U-shaped cross-section defining a main plate section and two side plate sections. A rectangular opening is formed at the main plate section, and a plurality of grid wires extend in a lengthwise direction of the main plate section and at one side thereof. Each end portion of each grid wire is soldered to each lengthwise end portion of the main plate section under tension. For providing a scorotron charger, a discharge wire is positioned opposite to the grid wires with respect to the main plate section, and each end of the discharge wire is fixed to the frame body in such a manner that the discharge wire extends in parallel with the grid wires.

Abstract: An apparatus and method for reducing contamination of an image transfer surface in an image transfer device includes a charging device for charging the image transfer surface. An airflow control system ventilates the charging device and restricts airflow adjacent the image transfer surface.

Abstract: In a xerographic printing apparatus, a scorotron places a uniform charge on a photoreceptor for forming electrostatic latent images. Three conductive pin arrays are disposed in a housing defined by sidewalls and a screen adjacent the photoreceptor. There can be provided insulative walls between adjacent pin arrays. The screen and a surface of the housing can be curved to correspond to a curvature of the photoreceptor.

Abstract: The present invention drives cleaning member moving devices for moving cleaning members of a plurality of chargers at the same time by a single cleaning motor to miniaturize an image forming apparatus and reduce the cost. Further, at the end time of cleaning, all the cleaning members are shifted to a predetermined area by the cleaning member moving devices, and the cleaning motor is stopped, thus the cleaning members remain in a charging area, and uneven charging is prevented.

Abstract: In a xerographic printing apparatus, a small footprint charging device may provide uniformity of charge and/or long life in a small diameter photoconductive drum. A grid to be parallel to the drum surface and including small wing shields may reduce or even prevent leakage of corona current to the photoconductor around the grid region, which may otherwise detract from charge uniformity.

Abstract: In a xerographic printing apparatus, a scorotron places a uniform charge on a photoreceptor for forming electrostatic latent images. Two conductive pin arrays are disposed in a housing defined by sidewalls and a grid adjacent the photoreceptor. For each array, the distance to the adjacent sidewall is 1.0 to 1.5 the distance to the grid.

Abstract: A charging device has a discharging electrode, a stabilizer plate having a rectangular section and accommodating the discharging electrode, and a grid arranged in a opening of the stabilizer plate, and at least one member of the discharging electrode, the stabilizer plate and the grid is made of an electrically conductive material containing 30% or more of nickel by weight or is plated with nickel or platinum at a rate from 30% to 80% by weight with respect to whole weight of the plated member. An image forming apparatus employs the charging device.

Abstract: A grid has a frame body in a U-shaped cross-section defining a main plate section and two side plate sections. A rectangular opening is formed at the main plate section, and a plurality of grid wires extend in a lengthwise direction of the main plate section and at one side thereof. Each end portion of each grid wire is soldered to each lengthwise end portion of the main plate section under tension. For providing a scorotoron charger, a discharge wire is positioned opposite to the grid wires with respect to the main plate section, and each end of the discharge wire is fixed to the frame body in such a manner that the discharge wire extends in parallel with the grid wires.

Abstract: Systems and methods for setting up grid voltage for a tandem pin charging device for charging a photoreceptor in a xerographic printing machine. A charge-generating emitter ratio of a first charging unit is determined and a first grid voltage is set based on the charge-generating emitter ratio of the first charging unit. A charge-generating emitter ratio of a offset voltage is then determined and a second grid voltage is set, based on the determined charge-generating emitter ratio of the offset voltage. A final voltage of a photoreceptor is then compared with a final target voltage.

Abstract: An image forming apparatus having a charger of a non-contact type opposed to a photosensitive body coated with a photosensitive layer by dipping for charging a surface of the photosensitive body and an interval between the surface of the photosensitive body and the charger is narrowed on a dip upper portion side of the photosensitive body and widened on a dip lower portion side thereof. When the charger is a scorotron charger having a discharge electrode and a grid, an interval between the grid and the surface of the photosensitive body is narrowed on the dip upper portion side of the photosensitive body and widened on the dip lower portion side.

Abstract: A charging system for uniform charging of charge retentive surfaces such as photoreceptors in imaging systems. The charging system includes corona producing elements and grid elements such as scorotron screens wherein the grid elements are arranged generally parallel to each other and have differentiated grid feature patterns. The differentiated grid feature patterns enable more uniform charging.

Abstract: The surface of a photosensitive body is charged by a scorotron charger including a discharge electrode, a back plate having an aperture on the bottom face, and a grid. Air is passed along the back plate for ventilation. The back plate also has a vent aperture on the side face. The aperture rate of the aperture on the bottom face of the part corresponding to the vent aperture is set lower than that on the bottom face of the other part, in the axial direction of the charger.

Abstract: By varying corona producing element height/projection, a more uniform charge potential is achieved. Elements, such as pins or teeth, are shorter at the edges of an element array and grow longer as one moves toward the center of the array. Such variation in height/projection overcomes shielding from adjacent teeth, as well as other effects, to yield the more uniform charging potential.

Abstract: A corona generating device, includes a conductor; a grid having a curved surface; and a frame for supporting the grid.

Abstract: In a high speed color printer wherein color images are produced by superposing a developed image atop another developed image, the improvement including a charging system for charging a surface, including: at least two coronodes; a housing with the at least two coronodes spaced from each other; a grid interposed between the surface and the at least two coronodes; a shield, interposed between the housing and the at least two coronodes; a first power supply for biasing the grid and shield; a second power supply for energizing each of the at least two coronodes; and a phase controller connected to the second power supply and adapted to control energizing of the at least two coronodes such that each of the at least two coronodes is charged at a phase difference.

Abstract: An image forming apparatus having a charger of a non-contact type opposed to a photosensitive body coated with a photosensitive layer by dipping for charging a surface of the photosensitive body and an interval between the surface of the photosensitive body and the charger is narrowed on a dip upper portion side of the photosensitive body and widened on a dip lower portion side thereof. When the charger is a scorotron charger having a discharge electrode and a grid, an interval between the grid and the surface of the photosensitive body is narrowed on the dip upper portion side of the photosensitive body and widened on the dip lower portion side.

Abstract: A method for determining an altitude with a corona generating device having a grid and a coronode and a power supply for supply power to the grid and coronode, including: setting the grid at a predefined voltage with the power supply; applying a charge output voltage and a charged output current to the coronode with the power supply; monitoring the charged output voltage and the charge output current to the coronode from the power supply until a predefined charge output voltage is reached; correlating charged output current to an altitude when the predefined charge output voltage is reached.

Abstract: A scorotron charging apparatus for producing a uniform charge on a charge retentive surface, comprising: corona producing means, spaced from the charge retentive surface, for emitting corona ions; and a grid, interposed between said corona producing means and the charge retentive surface, said grid having a first region of apertures disposed longitudinal with respect to the charge retentive surface and disposed substantially perpendicular to the direction of travel of the charge retentive surface, and a second region of apertures, adjacent to said first region of apertures, disposed longitudinal with respect to the charge retentive surface, said first region of apertures having an open area substantial higher than said second region of apertures.

Abstract: In a high speed color printer wherein color images are produce by superposing a developed image atop another developed image, the improvement comprising a charging system for charging a surface, including: at least two coronodes; a housing with at least two coronodes spaced from each other; a grid interposed between the surface and said at least two coronodes; a shield, interposed between the housing and said at least two coronodes; a first power supply for biasing the grid and shield; a second power supply for energizing each of said at least two coronodes; and a phase control connected to the power supply and adapted to control energizing of said at least two coronodes such that each of said at least two coronodes is charged at a phase difference.

Abstract: A charging device assembly used within a reprographic machine having a hollow shell containing the charging device, an attachment mechanism that fastens the charging device to the hollow shell in a predetermined position, a pair of end covers at either end of the hollow shell and an electrical connector on the shell that is coupled to the charging device. The shell can be conductive or insulative and is formed with features that facilitate easy mounting and removing of the charging device assembly.

Abstract: A corona generating device, includes a conductor; a grid having a curved surface; and a frame for supporting said grid.

Abstract: A combined charge/recharge xerographic power supply is provided that utilizes one power supply to drive the charge pin scorotron and recharge discorotron grids of a electrophotographic or xerographic system. The power supply uses recycled power from the pin scorotron grid to drive the discorotron grid. In particular, the power supply uses power that is dissipated in the traditional shunt regulator attached to the pin scorotron grid terminal to drive and provide active current to the discorotron grid through a series-pass regulation circuit. Thereby providing reduced electromagnetic emissions and reduced unit manufacturing costs.

Abstract: A combined charge/recharge xerographic power supply is provided that utilizes one power supply to drive the charge pin scorotron and recharge discorotron grids of a electrophotographic or xerographic system. The power supply uses recycled power from the pin scorotron grid to drive the discorotron grid. In particular, the power supply uses power that is dissipated in the traditional shunt regulator attached to the pin scorotron grid terminal to drive and provide active current to the discorotron grid through a series-pass regulation circuit. Thereby providing reduced electromagnetic emissions and reduced unit manufacturing costs.

Abstract: A single piece control grid electrode for a corona charging device for charging a curvilinear shaped dielectric support member with improved charging uniformity and consistency and with lower assembly and service cost. The single piece control grid is formed by a plurality of integral planar segments angularly oriented with respect to each other so that each segment may be equally spaced from the curvilinear shaped dielectric support member.

Abstract: A grid has a frame body in a U-shaped cross-section defining a main plate section and two side plate sections. A rectangular opening is formed at the main plate section, and a plurality of grid wires extend in a lengthwise direction of the main plate section and at one side thereof. Each end portion of each grid wire is soldered to each lengthwise end portion of the main plate section under tension. For providing a scorotoron charger, a discharge wire is positioned opposite to the grid wires with respect to the main plate section, and each end of the discharge wire is fixed to the frame body in such a manner that the discharge wire extends in parallel with the grid wires.

Abstract: A charging device which charges a body to be charged. At least a pair of linear electrodes is provided on a substrate so as to be close to each other. Walls are provided near the linear electrodes. Each of the walls has a height larger than a line width of each of the linear electrodes. The linear electrodes are surrounded by the walls and the substrate. The charging device alternatively includes a plurality of dielectrics and electrodes disposed along a first direction facing a drum so that the plurality of dielectrics sandwich the plurality of electrodes along a second direction perpendicular to the first direction, the dielectrics have a height larger than a height of the electrodes along the first direction, and at least two neighboring electrodes have different shapes.

Abstract: A corona cartridge for charging a photoreceptor in high-speed electrophotographic applications may include a comb-like corona charging device electronically connected to operate with the photoreceptor, and one or more excess comb-like corona charging devices stored on a shaft or in a dispenser that may be advanced automatically to replace the electronically connected corona charging device when it wears out. The number of excess comb-like corona charging devices (including the electronically connected corona charging device) may be tailored to last as long as the photoreceptor, which may run many months even in high-use operations. Accordingly, the high-speed electrophotographic applications may need to be serviced only when the photoreceptor wears out, thus significantly reducing the maintenance frequency without the side effect of increased ozone production, as in the case of wire-type corona charging devices.

Abstract: In DC pin scorotron charging apparatus for charging a photoreceptor to a final voltage, a first DC pin scorotron charging device initially charges the photoreceptor to an intermediate overshoot voltage and a second DC pin scorotron charging device thereafter uniformly charges the photoreceptor to the final voltage. The first DC pin scorotron charging device provides a generally high percent open control grid area, a generally high emitter slope, and a generally high emitter pin current. The second DC pin scorotron charging device provides a generally low percent open control grid area, a generally low emitter slope, and a generally low emitter pin current.

Abstract: A charging device which has a grid disposed between a discharge element and the photosensitive drum. The grid is formed of a regulating portion having a mesh configuration for the range opposing the image area on the photosensitive drum and non-regulating portions with openings for the range opposing the non-image area. The flow of ions discharged from the discharge element is regulated as to their passage through the grid thereby so as to be uniform and charge the image area on the photosensitive drum uniformly. The flow of ions reaches the non-image area without being shaded by the grid, so as to enhance the surface potential for prevention against toner adherence.

Abstract: A corona generator including a body and a first support secured to the body is provided. The corona generator also includes a second support secured to the body and spaced from the first support. The corona generator also includes an electrode mounted to the first support and to the second support.

Abstract: A scorotron charging apparatus includes a wire, a shield, a grid, and a side seal arranged between the grid and the shield. The side seal includes a conductive material.

Abstract: A device for preventing contamination of a print sheet and the reduction in the effectiveness of a scorotron type charger by free toner and paper particles. The device includes a paper dust eliminator extending the length of a photosensitive member and a wiping mechanism at each end of the photosensitive member for removing free toner that has accumulated there. Further, a partition that separates the developing section from the charger can be provided to further reduce free toner from attaching to the charger.

Abstract: The present invention relates to a corona charging apparatus for charging a body to be charged that has a discharge wire electrode to which a voltage is applied, a shield electrode having an opening opposed to the body to be charged, a grid electrode disposed in the opening, a power supply for applying a voltage to the grid electrode, and a constant voltage generating element electrically connected to the grid electrode, the constant voltage generating element generating predetermined voltage when current flows into the constant voltage generating element, and rated voltage of the constant voltage generating element is equal to or greater than the voltage applied to the grid electrode from the power supply.

Abstract: A corona generator including a body and a first support secured to the body is provided. The corona generator also includes a second support secured to the body and spaced from the first support. The corona generator also includes an electrode mounted to the first support and to the second support.

Abstract: A charging device which has a grid disposed between a discharge element and the photosensitive drum. The grid is formed of a regulating portion having a mesh configuration for the range opposing the image area on the photosensitive drum and non-regulating portions with openings for the range opposing the non-image area. The flow of ions discharged from the discharge element is regulated as to their passage through the grid thereby so as to be uniform and charge the image area on the photosensitive drum uniformly. The flow of ions reaches the non-image area without being shaded by the grid, so as to enhance the surface potential for prevention against toner adherence.

Abstract: An image-forming apparatus is provided with: a rotatable photoreceptor; a charging device for charging the surface of the photoreceptor to a predetermined electric potential. A device for corona discharging, the charging device has a control electrode for controlling the quantity of corona ions that are allowed to reach the photoreceptor. A latent image forming device for forming an electrostatic latent image on the photoreceptor that has been charged by the charging device by use of light irradiation. There is a developing device for developing the electrostatic latent image by using a developer; and a control voltage supply device for supplying a control voltage to the control electrode and for switching the control voltage to a plurality of stages from a low-voltage side to a high-voltage side until the surface electric potential of the photoreceptor has risen to a predetermined electric potential.

Abstract: In an imaging cartridge for forming images at least including a corona charging device and an object to be charged, a discharging electrode unit in the corona charging device is supported in such a manner that the electrode unit can be separately detached therefrom and installed thereto without being obstructed by the object to be charged or by a grid electrode from a side opposite to the member to be charged.

Abstract: A grid electrode for attachment to a corona charger includes a series of substantially parallel grid wires extending in a longitudinal direction of the wires. A flat metallic plate member is formed integral with the wires at one of the longitudinal ends of the wires. A cap member is connected to the plate member. The cap member includes a cover segment having a surface that overlies and is in planar contact engagement with a substantial portion of a respective plate member with a thickness of at least 0.5 millimeters and the cover segment being formed of a material that is substantially electrically more resistive than the flat metallic plate member.

Abstract: In an electrostatographic imaging apparatus employing at least one charging device, scorotron which consists of one or more fine wires supported on insulated blocks spaced between the photoconductive surface and a conductive or insulative surface parallel to it. A screen or grid is interposed between the corona wires and the photoconductive surface and the grid is maintained at a potential roughly equal to the potential desired on the photoconductive surface. The scorotrons geometry, the individual wires are from 1/2 to 11/2 inches apart and are spaced from the grid by about 3/4 of an inch. Field enhancement electrode(s) are placed on the screen and are biased at the same potential as the screen. The field enhancement electrode(s) enhance electrical performance.

Abstract: A high slope charging device including a DC portion followed by an AC portion. The high slope device includes an insulative shell housing, an electrode and a corona wire. The electrode is coupled to direct current power source which supplies a constant potential to the electrode thereby generating a corona at the electrode. An alternating current power source supplies an alternating voltage to the corona wire. The high slope device beneficially is designed such that both the electrode and the corona wire charge a charge retentive surface to the same potential.

Abstract: An image forming apparatus includes: a photosensitive unit having a surface portion of negatively charging property and moved in a predetermined direction; a first charging device disposed opposite to the photosensitive unit with a first spacing therebetween and for charging the surface of the photosensitive unit to a first charged potential of negative polarity by a negative voltage; a second charging device disposed opposite to the photosensitive unit with a second spacing therebetween at a position downstream of the first charging device in a movement direction of the photosensitive unit and for charging the surface of the photosensitive unit charged by the first charging device to a second charged potential of negative polarity by a positive voltage, the second charged potential having an absolute value smaller than an absolute value of the first charged potential; an electrostatic latent image forming device for forming an electrostatic latent image on the photosensitive unit; and a developer carrying de

Abstract: An image forming apparatus including a photosensitive member, a first developer for developing an electrostatic latent image on the photosensitive member, a charger adapted to charge the photosensitive member bearing a first developed image formed by the first developer and having a discharge electrode member and a shield member surrounding the discharge electrode member, an exposure device for image-exposing the photosensitive member charged by the charger, a second developer for developing an electrostatic latent image formed by exposure of the exposure device, and a voltage apply device for applying voltage having the same polarity as that of the first developed image to the shield member.

Abstract: A setup method for a corona charger device used in an electrophotographic recording apparatus. The setup method includes operating the corona charger device in a calibration mode so that charge of a first polarity is output by the device and deposited upon a photoconductive recording member. The level of charge deposited upon the member is sensed and a position of the charger device relative to the member is adjusted so that the level of charge deposited upon the member is at a target level. The charge of the first polarity output for setup is opposite to that of charge output during the production run.

Abstract: A charging apparatus for applying a uniform electrostatic charge to a charge retentive surface is provided. The apparatus includes a housing and an array of pin electrodes supported by the housing and positioned adjacent the surface in a non-contact relationship. The apparatus also includes a generally U shaped shield connected to the housing and at least partially surrounding the array of pin electrodes. The apparatus also includes a grid positioned across distal ends of the shield. The grid defines an effective charge length and an effective grid width. The apparatus also includes a power supply operatively coupled to the pin electrodes for supplying a predetermined current to each of the pin electrode. The power supply provides a predetermined voltage to the grid.

Abstract: A corona charger for depositing an electrostatic charge on a charge retentive surface, without the creation of sheeting defects, the charger includes a coronode, and a power supply operating in cycles and providing in each of the cycles electrical power to the coronode to produce a net positive charging current with voltage to the coronode from the power supply operating in a portion of each cycle with a positive polarity to generate positive corona emissions. The power supply operates so that an AC component of the voltage provided by the power supply has a positive polarity in the range of about 60% to about 85% of each cycle. When operating in a broader range of greater than 50% but less than 100%, DC equivalent current to the coronode is controlled below a value causing sheeting.

Abstract: An image-forming apparatus for forming image through the electric charging of a photosensitive material drum, exposure to light, developing and transfer, wherein a developing device also works to clean the toner remaining on the photosensitive material; an electric charge for effecting the electric charging has a scorotron charger located within .+-.45.degree. from a perpendicular downwardly drawn from the center of the photosensitive material drum, and has a hole on the side opposite to the opening for charging; and an electric field E.sub.1 between a wire and a grid in the scorotron charger is set to be stronger than an electric field E.sub.2 between the wire and a shield.

Abstract: A scorotron charger has a charging wire extending in a specified direction supported in a housing member including a pair of side walls each extending in a direction parallel to the charging wire. An electrode member having a U-shape in cross section is mounted in the housing member and has a bottom plate in the form of a a grid electrode and a pair of upright side plates extending along the charging wire. A plurality of cutouts are formed in the side plates and are so arranged that positions of the cutouts in one side plate are displaced from that of cutouts in the other side plate. A plurality of projections are formed on the side walls of the housing member at positions corresponding to the respective cutouts for engaging with the cutouts.

Abstract: A system is disclosed allowing a plurality of conforming customer premise equipment ("CCPEs") on a single telephone line to display a third party's caller information while users are communicating with a second party. Through a self-arbitration process, one CCPE of the plurality of CCPEs is a primary CCPE, whereas the remaining CCPE(s) are secondary CCPE(s). While the users are communicating with the second party using any one or more of the CCPEs, each CCPE detects whether a CPE alerting signal ("CAS") tone has been transmitted by the central office, thereby detecting when the third party is calling. Each CCPE responds by disconnecting the CCPE's telephone from the telephone line. After all of the CCPEs are on-hook, the primary CCPE then goes off-hook and transmits a CAS acknowledgement ("CAS ACK") signal to the central office. All of the CCPEs then wait for the central office to transmit the CID information in response to the CAS ACK signal.

Abstract: This invention pertains to a sawtooth AC charger (10) in which an AC voltage signal applied to sawtooth blades (12) has a duty cycle greater than 50%. Duty cycles above about 70% increase the uniformity of negative charging without significantly increasing the peak voltage to the sawtooth blades.

Abstract: An electrophotographing method using a corona charging device having areas with and without a grid. Prior to at least a second exposure step, a charging step is effected using both areas relative to the grid. A voltage applied to the grid in the second charging is lower than that in the first charging, and lower than a potential of a non-image region of the photosensitive body.