Abstract: Apparatus and methods reduce, and preferably prevent, contamination of a surface or component to be charged or acted upon by a corona generating device. When a voltage is applied to the corona generating device, corona winds having a plurality of corona vortices are formed. Air is pulled via at least one drawing port of the corona generating device. At least one substantially continuous air curtain is formed along a side of the corona generating device when air is pulled via the drawing port of the corona generating device. The formation of the continuous air curtain is not dependent on air being pushed into the corona generating device. Preferably the substantially continuous air curtain extends from substantially one end of the corona generating device, at least a distance equivalent to a greatest continuous total length of the plurality of corona vortices and any portion of the corona generating device situated therebetween.

Abstract: In an image forming apparatus according to the present invention, the force of a tension spring returning to its original position is utilized to vibrate or impact a conductive member using a predetermined timing, one end of the conductive member being fixed and the other end of the conductive member being connected to a knob via a tension spring. This serves to remove attachments adhering to the tips of the conductive member.

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: An image forming apparatus includes an image carrier (1), a corona charger (5) in which a discharge electrode (11) is arranged in a conductive shield (9) having an open face on a side facing the image carrier (1) and a face in which a first ventilation opening (10) is formed, and a duct (6) arranged adjacent to the corona charger (5), has an airflow opening (7). The conductive shield is provided with a wall member (22) at an end thereof on the downstream side in the direction of airflow created through the first ventilation opening and is provided with a second ventilation opening (23) in a face on the downstream side in the rotational direction of an image carrier and the duct has a third ventilation opening (24) facing the second ventilation opening and a fourth ventilation opening (25) in a face of the duct.

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: A charging device assembly used within a reprographic machine having a hollow shell containing the charging device, an attachment mechanism that retains the charging device relative 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 coupled to the charging device. The hollow shell can be conductive or insulative and is formed with features that facilitate easy mounting and removing of the elements of the charging device assembly.

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: An improved dircorotron shield for use in an electrophotographic photorecptor printer. The improved dicorotron shield uses titanium or a titanium alloy to form the dicorotron shield, thereby eliminating the need for a base layer or coating to neutralize the production of deteriorative acids that impair or weaken the surface of the photoreceptor. The use of titanium or a titanium alloy limits the production of unstable ozone O3 otherwise occurring due to the high energy agitation of atmospheric oxygen O2 caused by the charging of the corona device the dicorotron shield surrounds. By reducing the production of ozone O3, the formation of acids is reduced as well. As a result of the reduced acids formed, the titanium or titanium alloy dicorotron shield requires less cleaning or maintenance or replacement.

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 support and tensioning device for an elongated corona generating electrode includes a corona charger shield member that includes a first set of wall members for serving as a shield for a corona generating electrode. The shield member includes a second set of wall members shaped to define a recess formed at one end of the shield member for receiving therein a plunger member and a spring. The recess includes an inner positioned land for engaging a head end of the spring. The second set of wall members define the recess and include walls located to define a key slot opening which extends in a longitudinal direction of the shield member. A spring resides in the recess and engages the land to restrict movement of the spring within the recess. A hollow plunger member has a generally cylindrical sidewall for supporting the plunger for rotational movement in the recess and a land on or near a head end portion of the plunger member engages a tail end of the spring.

Abstract: A mechanism and a method for generating a corona discharge by a wire-shaped corona discharge electrode provides that the corona discharge electrode is stretched between two end blocks that respectively contain a space for the acceptance of a respective electrode holder insert. The electrode holder insert has a rotational-symmetrical electrode receptacle element with an axially parallel electrode receptacle channel in the generated surface as well as a further electrode receptacle channel in an end face, the further channel adjoining the axially parallel channel and residing perpendicularly thereon, and also has an annular cap element that, proceeding from the end face containing the further electrode receptacle channel, can be pressed onto the electrode receptacle element with the corona discharge electrode guided in the electrode receptacle channels.

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: An AC corona charging arrangement includes a corona generating device connected through a capacitive connection to an AC voltage source and partially surrounded by a conductive shield connected to DC voltage source. In one embodiment the corona generating device is a wire having a diameter of about 50 microns and in another embodiment the corona generating device is a row of pins connected through corresponding capacitance to the AC voltage source. The presence of a capacitance between the AC voltage source and the corona generating device provides a curve representing the relationship between the current between the charging device and an adjacent conductive plate and the shield voltage which is concave downwardly, resulting in a high charging rate and greater uniformity of charging of a photoreceptor surface.

Abstract: A charging apparatus for applying a uniform electrostatic charge to a charge retentive surface is provided. The charging apparatus is operably electrically connectable to a power supply for supplying an electrical bias to the charging apparatus. The apparatus includes a housing and an electrode mounted to the housing and positioned adjacent the surface in a non-contact relationship therewith. The apparatus also includes a shield connected to the housing and at least partially surrounding the electrode. The apparatus also includes an electrical connector, electrically connected to the shield and electrically connectable to the power supply for providing an electrical bias to the shield. The electrical connector extends from the shield and is integral therewith.

Abstract: A charging device is provided which is suitable for use in a compact electrophotographic image forming apparatus. The charging device includes: a pair of support members spaced a predetermined distance; and a discharge wire stretched between the pair of support members with one end thereof being fixed to one of the support members and with a middle portion thereof being supported by the other support member. One end of a coil spring is connected to the other end of the discharge wire, and the other end of the coil spring is received by a hooking portion of an electrode. The electrode is fixed in the vicinity of one of the support members.

Abstract: A method and apparatus for achieving optimum noise control of multiple coronode wires in a copier/printer involves optimizing phase relationships of the voltage on the wires in such a way so as to steer the maximum part of the noise distribution profile in the direction best suited for absorption or dissipation. In a two corotron charging system, the coronodes are preferably charged to where the phase angle, charge frequency and spacing between wires are optimized. If desired, a sound absorption material could be added to the charging system.

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: An image forming apparatus includes an opening portion that opens toward a photosensitive body and has a stagnant portion in which discharge products produced by a discharging means stagnate. A partition member is disposed in the vicinity of an opening of the opening portion, the opening opposing a photosensitive body, the partition member preventing discharge products that fall from the stagnant portion from falling directly into contact with the photosensitive body.