Abstract: The transfer station of an electrostatographic apparatus includes a transfer corotron which assists the transfer of a developed image to a copy sheet. The shield of the transfer corotron is allowed to self-bias to a potential controlled by a Zener diode, and this potential is applied to a sheet guide member. Copy paper sheets are fed over a sheet guiding portion of the guide member towards the photoconductor drum, and while the sheets are in contact with the guide member they acquire the potential which is predetermined to ensure optimum transfer conditions.

Abstract: An apparatus for continuous corona treatment of materials, such as wire. An electrode is helically wound about a tubular glass dielectric, and the electrode is attached to a source of high voltage, high frequency power. In order to facilitate rapid passage of the treated material through the glass tube, blocks with internal pulleys are mounted at either end of the tube.

Abstract: A corona discharge device having a first corona wire and a second corona wire parallel to the first corona wire and in physical contact therewith, such that the forces created by the wires during energization prevent the vibration of the wires, thereby eliminating short circuiting and the need for costly wire-damping devices.

Abstract: A scorotron and control therefor for charging and/or discharging a charge retentive surface such as a photoreceptor of the type utilized in the process of xerographic printing. The control connects the wire grid of the scorotron to ground via a plurality of zener diodes and a variable resistor. The voltage across the variable resistor is low compared to the total circuit voltage so that variations in the grid current result in small variations in grid voltage. The control provides for compensation for out of tolerance zener diodes as well as for photoreceptor aging manufacturing tolerances and temperature elevation. When the variable resistor is a light dependent resistor a light emitting diode contained in a bridge network also containing a thermistor provides for automatic compensation due to elevation in photoreceptor temperature when such temperature is sensed by the thermistor.

Abstract: A corona discharge device includes a first electrode assembly comprising a roll formed of conductive material and a second electrode assembly including a conductive member having a ceramic element mounted on the conductive member in arranged generally parallel to the rotational axis of the conductive roll. According to a first embodiment, the second electrode assembly comprises a plurality of electrodes mounted for pivotal movement on one of a pair of support rods arranged in a parallel relation to each other and to the roll. First and second groups of electrodes are disposed on each of the respective rods in a staggered relation to each other.

Abstract: A process kit is detachably mounted in the main body of an image forming apparatus and includes a housing in which a photosensitive member, a corona discharger and a developing device are mounted and held as a unit, the housing including an optical opening formed therein upstream of the corona discharger for conducting a homogeneous light to the photosensitive member to eliminate any remaining charge thereon and an opening of exposure for conducting a light of information to the photosensitive member, the exposure opening being located between the corona discharger and the developing device.

Abstract: A charge scorotron having a U-shaped shield positionable opposite a photoreceptor, a corona discharge wire in the shield, a grid between the wire and the photoreceptor for controlling the emission of ions to the photoreceptor, the grid being electrically subdivided into a first grid segment with a length substantially equal to the dimension of the smallest size copy sheet with subsequent grid segments having lengths chosen when combined with the first grid segment and each other to substantially equal various larger size copy sheets, switches responsive to the position of an adjustable sheet guide in the copy sheet supply tray connecting each of the other grid segments with the grid bias selectively, the switches when not actuated coupling the grid segment associated therewith to ground whereby the area of the photoreceptor charged is determined by the number of grid segments coupled to the grid bias in response to the size copy sheet being processed.

Abstract: A corona generating device for depositing negative charge on an imaging surface carried on conductive substrate comprises at least one elongated conductive corona discharge electrode, means to connect the electrode to a corona generating potential source, at least one element adjacent the corona discharge electrode capable of adsorbing nitrogen oxide species generated once the corona generating electrode is energized and capable of desorbing nitrogen oxide species once that electrode is not energized, the element being coated with a substantially continuous thin layer of a paint containing reactive metal particles which will combine with the nitrogen oxide species, the reactive metal being present in the paint in an amount sufficient to neutralize the nitrogen oxide species when generated.

Abstract: A corona generating device for depositing negative charge on an imaging surface carried on conductive substrate comprises at least one elongated conductive corona discharge electrode, means to connect the electrode to a corona generating potential source, at least one element adjacent the corona discharge electrode capable of adsorbing nitrogen oxide species generated once the corona generating electrode is energized and capable of desorbing nitrogen oxide species once that electrode is not energized, the element being plated with a substantially continuous thin layer of lead to neutralize the nitrogen oxide species when generated.

Abstract: A corona generating device for depositing negative charge on an imaging surface carried on conductive substrate comprises at least one elongated conductive corona discharge electrode, means to connect the electrode to a corona generating potential source, at least one element adjacent the corona discharge electrode capable of adsorbing nitrogen oxide species generated once the corona generating electrode is energized and capable of desorbing nitrogen oxide species once that electrode is not energized, the element being coated with a substantially continuous thin dehydrated alkaline film of an alkali silicate to neutralize the nitrogen oxide species when generated.

Abstract: In an image control device for an electrophotographic copier, a temperature on the surface of a photoconductive element or in the vicinity thereof is sensed. The amount of charge deposited on the photoconductive element is controlled to maintain the potential in a background constant in response to a sensed temperature.

Abstract: A corona treater includes an active electrode which has one or more insulated electrode elements slidably supported by an insulating track. A contact spring connects each electrode element to a conductive electrode bar embedded in the track, and sheet material to be treated is fed through a treatment zone created between an active discharge surface on each electrode element and a bare metal roller electrode.

Abstract: An electrophotographic copying machine includes a main housing and an internal frame which can be detachably mounted in position defined in the main housing. The internal frame supports a photosensitive member in the form of an endless belt and a grid electrode. The main housing is provided with a corona discharger comprised of a corona wire and a casing partly surrounding the corona wire to define an opening through which corona ions are emitted. When the internal frame is mounted in position in the main housing, the grid electrode comes to be located opposite to the opening thereby functioning as a part of the corona discharger. Thus, when the internal frame is dismounted, the opening of corona discharger is exposed thereby allowing easy access to the corona wire.

Abstract: A minaturized self limiting corona generator for charging a receiver surface includes a plurality of corona emitting wires housed in respective biased conductive shields with the wires being spaced farther from the receiver surface than the wire-to-shield spacing in order to provide self limiting of surface potential on the receiver surface.

Abstract: An ion generator for the formation of electrostatic images, including two electrodes at opposite faces of a solid dielectric member, using a threshold multiplexing principle for the drive circuit. The apparatus provides a drive signal to each electrode to generate ions in an air region adjacent one of the electrodes, which ions are extracted for electrostatic imaging. Two drive signals each consisting of a sinusoidal alternating potential, out of phase by 180.degree., intermittently induce the production and extraction of ions. Other time-varying potentials of like electrical characteristics may be used, providing a number of operating advantages. The ion generator produces ions only during print periods, and requires reduced power to achieve given ion outputs. The control electrode may be partially encapsulated to limit the discharge region. Drive circuitry such as low source impedance gated oscillators, or other low impedance drivers, reduce capacitive "cross-talk" in a multielectrode device.

Abstract: A corona discharge device includes a roll formed of a conductive material and a plurality of segments mounted on a support and arranged in spaced relation from the surface of the roll in an alignment generally parallel to the roll's rotational axis. Each segment includes a hollow insulator having an outer surface adapted to be disposed adjacent to said roll and a wall extending away therefrom. The conductive body is disposed within said insulator and in an opposed relation to said outer surface. The conductive means is coupled to the conductive body and extends outwardly from said insulator for being coupled to said support means for movement of said segment away from said roll. An insulating material can be used to fill the remaining portion of said insulator and to surround said conductive means.

Abstract: A copying or printing apparatus has a photoconductive surface, a charging station to impart an electrostatic charge to at least a portion of the photoconductive surface, an exposure station, a development station and a transfer station followed by a discharge station, at the charging station a charging device in the form of a support surface having a plurality of conductive fibers extending therefrom to a substantially uniform height toward the photoconductive surface is provided and which has a conductor connected to a potential voltage source.

Abstract: In a recording apparatus, a recording paper is separated from an image retaining member after the transfer of a toner image onto the recording paper by generating an a.c. corona discharge so as to eliminate or reduce electrostatic forces generated between the image retaining member and the recording paper. An insulator is arranged between the separating electrode and the recording paper during the a.c. corona discharge so as to moderate the sharpness of the spatial distribution of the corona discharge current.

Abstract: The printing unit (1) operating with an electrostatic printing aid has an inductor device (7) for transmitting an electrostatic charge to an outer-shell layer (5) of a back-up cylinder (4). The inductor device is provided on one end face (14) of the back-up cylinder and engages over this end face in the manner of a lid. A continuous annular air gap (15) is located between the end face and the inductor device. Inductor electrodes (9) serve for transmitting the electrostatic charge to the outer-shell layer in a contactless manner and are arranged, concealed against outside access, on the inner face of the inductor device and are aligned by means of their electrode tips with an end-face edge (10) of the outer-shell layer (5). So that no impurities can penetrate into the air gap, it is sealed off or constantly scavenged by compressed air.

Abstract: A method and apparatus for producing a uniform elongate corona is provided. The apparatus includes at least one stationary corona electrode coupled to a supply of corona voltage. A moving ground electrode having a series of equally-spaced grounding points is coupled to a bias circuit that returns to ground. The moving ground electrode may be arranged to form a helix on a motor-driven insulating rod, with the longitudinal axis of the rod parallel to the stationary elongate corona electrode at a predetermined distance therefrom. The supply of corona power provides a high negative D.C. voltage or a series of high frequency negative high voltage pulses. The preferred bias circuits include one of a self-bias provided by a high resistance; a high frequency pulsating D.C. power supply circuit; or a fixed value negative D.C. power supply circuit.

Abstract: A corona treater includes an active electrode which has one or more insulated electrode elements slidably supported by an insulating track. A contact spring connects each electrode element to a conductive electrode bar embedded in the track, and sheet material to be treated is fed through a treatment zone created between an active discharge surface on each electrode element and a bare metal roller electrode.

Abstract: The invention provides a support member which carries at least one axially aligned corona electrode, and a conductive biasing member wrapped around both the support member and the electrode. The biasing member is preferably a wire wrapped about the support and electrode to form a coil and preferably there are four electrodes. A conductor extends the length of the coil to ensure continuity should the biasing member fail locally.

Abstract: In an electrophotographic reproduction apparatus and method, a moving photoconductor is charged by a primary corona charger that includes a corona wire. Nonuniformities in the charge pattern produced on the photoconductor by this primary line charger are reduced by subjecting the photoconductor to a second corona charger having point charging electrodes.

Abstract: A corona discharging apparatus used in an electrostatic photographic copying machine includes a shield case provided with an open portion facing a circumferential surface of a sensitive drum. The shield case is detachably and dislocatably provided with a shield cover for regulating an electrifying width achieved by a thin wire for corona discharging arranged in the shield case at a longitudinal end of the shield case over the open portion.

Abstract: In charging a surface of a chargeable member by AC corona discharge, the current difference between the plus and the minus component of the AC corona discharge current is detected, and the current difference is maintained constant to thereby stably produce a constant surface potential on the chargeable member.

Abstract: In a xerographic reproduction machine there is provided apparatus for partially neutralizing charge on the backside of a copy sheet electrostatically adhered to a photoconductive surface. Included in the apparatus is a conductive wire having a relatively thick insulative outer coating which is sufficiently thick that with an a.c. voltage applied to the conductive wire there is substantially no net d.c. current flow from the wire in the absence of an external electrostatic field. Such a construction of wire and outer coating is known as a dicorotron electrode. A net positive current flows from the wire to the back of the paper when an external electrostatic field is established between the conductive shield and the copy sheet by moving said copy sheet with a positive voltage on its backside past the conductive wire.

Abstract: Apparatus is described for providing controlled corona charging of an electrophotographic member that moves past a corona charging electrode. A corona sensor probe near the charging electrode receives a sample of the corona current flow from the electrode that is proportional to the current flow as it may be modified by extraneous influence, including air pressure, humidity, and corona electrode potential. The probe produces a signal that is adapted to vary the movement rate of the member past the charging electrode, being faster for a sensed increase of corona current and slower for a sensed decrease of corona current. The effective result is an electric charge on the electrophotographic member surface that is uniformly about constant, independent of the variations wrought by most external influences.

Abstract: An image reproducing apparatus includes an ion modulating electrode and a device for imparting oscillation thereto. The ion modulating electrode is formed of a continuous layer of conductive material, a segmented layer of conductive material, an insulating layer interposed between the continuous and segmented layers, and at least a row of apertures for modulating ion flow generated by a charge generator. At least one embodiment of the device for imparting oscillation includes a rotor or cam rotatable to apply oscillation to a receiving plate. In another embodiment, the oscillation imparting device is formed of a permanent magnet, a coil placed in the magnetic field generated by the magnet, an oscillator for applying an alternating current to the coil and an oscillation element connected to the coil.

Abstract: A method and apparatus for providing uniform corona bonding between and across the width of a plurality of layers of material each having a generally uniform thickness and width whereby, if desired, the plurality of layers may be easily and uniformly separated. Uniformity of bond is achieved by configuring the outer ends of an otherwise straight electrode, placed at an optimum effective bonding position, in proportion to the higher corona energy levels found to occur at the ends of the corona electrode bar.

Abstract: A method and apparatus for the treatment of thin sheeting by subjecting said sheeting to a corona discharge. Two elongated electrodes are provided in a fixed spatial relationship. The first electrode is coated with a dielectric material and electrically grounded. The second electrode is machined to include a plurality of intersecting furrows which define a plurality of mesa structures, each having at least one acute angle corner. An electrical potential is applied to the second electrode and the sheeting material is then transported between the two electrodes. The mesa structures machined into the surface of the second electrode serve to enhance the amount of corona created by a given amount of electrical potential.

Abstract: A novel apparatus for the collection and removal of ozone generated during the operation of machines, such as an electrostatographic copying machine, is disclosed which includes the substantially complete collection of ozone generated by the use of an apertured plenum at the point of ozone generation, and the substantially complete removal of the ozone collected by the use of a fixed bed filtering device which has a large bed area to volume ratio. The disclosed apparatus permits the substantially complete collection of all ozone generated in a relatively small volume of air accomplished with a low pressure drop, so that the ozone collection and removal system would not interfere with the normal operation of the electrostatographic copying machine.

Abstract: A corona discharging device in an electrophotographic apparatus used for discharging or uniformly charging the surface of a latent image bearing member. This discharging device has corona wires to which a voltage of a predetermined polarity is applied and corona wires to which a voltage of the opposite polarity to the predetermined polarity is applied, and alternately applies corona discharges to the image bearing member. Grids are provided between the corona wires and the image bearing member and a common bias voltage is applied to the grids. The final surface potential of the latent image bearing member approaches the grid bias potential.

Abstract: A catalyst capable of decomposing ozone comprising active carbon with silver deposited on the surfaces thereof.

Abstract: This specification discloses a method of making the grid of a corona discharger device and a method of mounting the corona discharger device on an apparatus body, and more particularly a method of easily forming a number of grids and a method of mounting a corona discharger device having such grids on an apparatus body. The grid making method of the present invention comprises winding an electrically conductive thin wire on a rotatable body, fixing the wound thin wire in the direction of the rotational axis of the rotatable body, fixing the wound thin wire in the direction of the rotational axis of the rotatable body by means of fixing members, and cutting the thin wire in the direction of the rotational axis.

Abstract: A method and an apparatus for charging a dielectric layer electrostatically to a predetermined potential. An AC electrode is arranged at a distance from the dielectric layer and connected to one output of an AC voltage generator. The AC voltage generator has the other output connected to an output of a DC voltage generator. Between the AC electrode and the dielectric layer there is a DC electrode which is connected to the other output of the AC voltage generator. The dielectric layer rests on a counter-electrode which is connected to the other output of the DC voltage generator and is at ground potential. Each of the electrodes can comprise one or a plurality of mutually insulated single electrodes.

Abstract: An improvement in an electrophotocopying machine having a photosensitive member. The improvement includes at least two rollers for charging the photosensitive member or at least two rollers for transferring a toned image from the photosensitive member to a plain copy sheet. The rollers are mounted on a turret adjacent the photosensitive member. The improvement also includes a mechanism for rotating one of the rollers into its operating position adjacent the photosensitive member and the other of the rollers into a cleaning position removed from the photosensitive member, and a cleaning device for cleaning the other roller in its cleaning position.

Abstract: The invention relates to a corona discharge device of the scorotron system which is used for electrophotographic copying machines. According to the device the invention, an impedance element 11 is connected between grid wires 6 and the ground, and generates a voltage depending upon a corona current which flows from a corona discharge wire 8 to the grid wires 6. Here, one end of the impedance element is connected to an electrically conductive shielding plate 3. The impedance element is formed in the discharger as a unitary structure, and only one connector is required for the corona discharge wire. Hence, the positioning operation is facilitated and poor electrical connection is avoided.

Abstract: A sequential corona charging method including apparatus therefor which acts to provide several corona fields, each of its own distinct origin, which are brought together with some spatial overlap to act collectively to provide uniform charge current distribution throughout the surface of an electrophotographic medium. Independence from non-uniform charging brought about by the undesirable effects of electrostatic repulsion between adjacent electric corona fields is achieved through the rapid controlled on and off sequencing of overlapping field corona regions so that the active time coincident therebetween is negligible.

Abstract: A device for electron irradiation of rolled materials comprises an electron source arranged in a radiation protection chamber, and a drum for transportation of rolled material in a slotted irradiation zone, defined by the radiation protection chamber wall on one side and by a housing wall on the other side. The drum is made as a cylinder arranged on rims so that a part of said cylinder is located in the irradiation zone between the radiation protection chamber wall and the housing wall.

Abstract: A roller electrode is disclosed which comprises a tubular outer casing of dielectric material, a shaft and an electrically conductive composition filling the annular cavity defined by the casing and shaft. The composition, which is in intimate contact with the casing and shaft, may comprise a cementitious matrix, such as casting plaster, in which conductive particles of carbon or the like are bound.

Abstract: A xerographic device having a reusable photoconductor which is subjected in repeating cycles to (1) a charge corona whereat the photoconductor is uniformly charged to a negative voltage, (2) an imaging station whereat a working portion of the photoconductor is selectively discharged, to leave a charged area on this working portion defining a negative electrostatic latent image to be reproduced on copy paper, (3) a magnetic brush developing station whereat negatively charged carrier beads transport positively charged toner to the photoconductor's latent image, to leave a toned image on the photoconductor, (4) a transfer station, including a negative transfer corona, whereat a portion of the photoconductor's toned image is transferred to copy paper, (5) a positive preclean corona whereat the negatively charged photoconductor and its positive residual toner are subjected to a positive charge, and (6) a cleaning station whereat the photoconductor is cleaned by a brush having an affinity for positively charged par

Abstract: Process for eliminating the need for a separate cleaning station in a one-cycle electrophotographic document copier machine of the transfer type. A backcharge corona generator is added to provide an overcharge/backcharge process to obtain the desired level of charge on the photoconductive system prior to exposure of the photoreceptor to the subject. In that manner, residual toner remaining on the photoconductor after production of the previous copy is cleaned simultaneously with the development of the succeeding copy.

Abstract: In an electrostatic copier including a device for the electrostatic transfer of a toner image disposed on an electrophotographic recording material to an image receiving material whose rear side is chargeable by a corona discharge device composed of an elongate electrically conductive shielding housing and at least one corona discharge wire clamped in an insulated manner between the housing ends, there are provided: a carrier to which the corona discharge device is fixed; a slide member supporting the carrier and with respect to which the carrier is movable between two end positions for setting the distance between the corona discharge device and the surface of the recording material; a control member connected for moving the carrier between its end positions; guide rails extending parallel to the recording material surface and fixed to the copier; and guide elements fixed to the slide member and arranged to travel along the rails to guide the movement of the slide member, the guide elements being removable f

Abstract: Disclosed is an accurately adjustable mount for supporting a corona assembly of a photocopying machine. The accurate adjustment of the separation between the corona wires and the photosensitive surface of the photocopying machine is accomplished by separate cam mechanisms located at either end of the corona assembly. Locking means are provided for securing the corona assembly after the proper separation has been established by the cam mechanisms.

Abstract: Primary charging of a moving electrographic photoconductor to a nominal potential level is achieved with low sensitivity to variation in system parameters, such as photoconductor capacitance, photoconductor velocity and/or charger efficiency. Separately-addressed, AC corona discharge units are arranged and predeterminedly biased to first substantially overcharge the photoconductor relative to the nominal potential and then discharge the photoconductor to exit at the nominal potential level.

Abstract: A plurality of parallel wires (27) are disposed between a corona discharge electrode (24) and a surface (13) to be electrostatically charged. The surface (13) is moved relative to the electrode (24) and wires (27). The wires (27) are equally spaced from each other in a plane (28) which is inclined relative to the surface (13) in such a manner that the spacing between the wires (27) and the surface (13) increases in the direction of movement of the surface (13) relative to the wires (27). A high voltage for corona discharge is applied to the electrode (24). A low voltage is applied to the wires (27) to prevent the surface (13) from being charged above a predetermined potential. The low voltage may be applied to the wires (27) by means of a zener diode (31) connected between the wires (27) and ground which prevents a potential induced in the wires (27) from the electrode (24) from exceeding the zener voltage of the diode (31).

Abstract: Charging, imaging, developing, transfer and cleaning units are operatively arranged about the circumference of a rotary photoconductive drum, the developing unit comprising a magnetic brush. A discharge unit is disposed between the transfer unit and the cleaning unit and comprises a light source and a corona discharge element to simultaneously illuminate the drum causing photoconduction and expose the drum to an electric field thereby neutralizing any residual charge on the drum and residual toner particles remaining on the drum after the transfer operation. The residual toner is subsequently removed by the magnetic brush of the developing unit.

Abstract: In an electrostatographic copying apparatus in which the imaging material is transferred to the copy member by electrical transfer members which leave electrostatic charges on the copy member resisting stripping of the copy member from the original image support surface, and in which a detacking corona generator is provided to partially neutralize those charges before the stripping of the lead edge of the copy member. There is provided an automatic switching system to apply a non-uniform increased transfer charge to the lead edge area of each copy member in comparison to the body of the copy prior to the detacking to improve the effective image transfer to the lead edge area of the copy after stripping. This is preferably provided by a transient over-shoot in the ouptut voltage of a constant current power supply for the transfer members for the lead edge.

Abstract: Photocopying machine comprising shield elements which are provided between an electrophotosensitive medium and a corona discharge unit at a transfer station, define a slit to permit transfer of conductive toner particles onto copy paper charged by the corona discharge unit but prevent imposition on the paper of a charge liable to cause early transfer of toner particles or of a charge liable to cause cancellation of the charge of the toner particles, and hence detachment, of toner particles on the copy paper.

Abstract: Submicron-sized oxide particles are produced in a process in which coarse particles are fed into a vaporizing zone of a plasma burner, where they sublimate and finer particles are produced in a cooling zone.