Abstract: A transfer apparatus is provided of the type in which a toner image formed on a photosensitive member is transferred onto a transfer or copy sheet. The apparatus is used in a copying machine of a so-called delivery type in which the sheet is conveyed using a sheet gripper. During the transfer of a toner image, the appartus applies a corona discharge to the rear side of the sheet which is of the opposite polarity from that of the toner image. The apparatus comprises a diaphragm member for restricting an opening of a transfer charger and disposed between the transfer charger and the photosensitive member, the diaphragm member being movable away from the photosensitive member as the sheet gripper passes between the transfer charger and the photosensitive member.

Abstract: In a process for the transfer printing of charge images the carrier of a primary charge image is covered with an insulating film the backside of which is electrically charged by means of a corona discharge under concentrated gaseous nitrogen, and the film now carrying the secondary charge image is subsequently removed from the carrier of the primary charge image.

Abstract: The recording of half-tone images by electrophotographic and electrographic recording processes can easily be controlled by a method of altering the gradation in electrostatographic recording of latent charge images of half-tone originals wherein a first latent charge image produced on a primary recording material is recorded as a second latent charge image of altered gradation on a secondary recording carrier by means of a charging current which is controlled by a slotted diaphragm.

Abstract: An electrode which has at least one internal channel and an adjustable gate or slot to permit passage of gaseous material to be ionized from the internal channel and then in proximity to one or more outside faces of the electrode in a suitable area of electron emission, the electrode being placed in an electrical field in convenient proximity to an electrode or body of opposite charge.

Abstract: Disclosed is an apparatus and method for controlling corona generated ozone emissions in electrostatographic copying equipment. This is achieved by directing ozone rich gases through a novel fluidized bed reactor located in an exhaust channel of an electrostatographic copier. The novel reactor is provided with means for continuously or periodically purging fine particles from the perforated wall of the catalyst containing chamber proximate to the exhaust end of the reactor; thereby, preventing such fine particles from becoming permanently entrained within such perforation and creating a substantial pressure drop between the interior of the catalyst containing chamber and the exterior of said chamber proximate to exhaust end of the reactor. The preferred ozone neutralization system contemplated for use in this invention is a multiple stage device wherein a number of reactors are connected to one another in series.

Abstract: A two cycle process electrophotographic copying device having charging, imaging, developing, transferring, and cleaning facilities, the arrangement being in the conventional sense, incorporates a combined charge and preclean corona unit that is operable to perform either a charging function or a precleaning function at the proper time during a copying/cleaning cycle and a combined precharge/transfer corona unit. The combined charge and preclean corona unit includes a dual bay corona which emits negative and positive ions and a common control grid for controlling the ion flow from each bay of the dual bay corona.

Abstract: An apparatus for providing a uniform charge upon a surface of a conductive base, the apparatus includes a longitudinally elongated corona discharge element, a potential source connected to the discharge element for applying a corona-generating potential, conveyor means for conveying at least one conductive base along a path in a direction along the length of the discharge element and a protective grid assembly disposed directly adjacent the discharge element. The grid assembly includes protective elements having sufficient resistance to prevent the conveyed base from contacting the discharge element and to cast a persistent electrical shadow on the conveyed base. The protective elements are skewed longitudinally of the discharge element and relative to the direction of the conveyed base whereby the electrical shadow cast by the protective element is equally distributed over the conveyed base.

Abstract: Grounded grid static discharge apparatus having a pair of spaced insulator blocks mounted in a shell. A grounded grid is fixed to the shell located adjacent to a sheet travel path. The insulator blocks have openings which serve as radial locators for a high voltage corona wire, extending between the blocks. A contact member, housed within one of the blocks, captures one end of the corona wire and positions the corona wire in relation to the respective opening of the block. A high voltage electrical coupling is made to the corona wire by inserting a male connector from a high voltage source into direct engagement with the contact member to complete the coupling with a minimum of electrical interfaces. The other insulator block has an end cap for capturing the opposite end of the corona wire. The end cap is urged in a direction to provide tension in the corona wire to maintain the wire in the radial locators for proper spatial positioning of the wire with respect to the shell and grid.

Abstract: A process is described for improving the ammonolytic stability of polyester textile yarn without substantial loss of its tensile strength which comprises exposing separated fibers of the yarn to corona discharge for a total of about 0.01 to 3 seconds at a speed of at least 100 feet per minute and then reforming the yarn. A cord made from this yarn is described, as well as a tire produced by bonding the cord to rubber.

Abstract: Disclosed are apparatus and method for electrostatically charging a moving electrophotographic film to a predetermined charge potential over wide variations in film movement speed. The apparatus comprises a corona discharge electrode, high voltage potential means for producing corona current flowing from the corona discharge electrode to the film, an electrically conductive control electrode extending parallel to and across the width of the film at a position less than 1/4 inch from the film and in the direction of film movement from the corona discharge electrode, and biasing means for biasing the control electrode at a potential proportional to the film predetermined charge potential for limiting the charge on the film to the predetermined charge potential.

Abstract: A control circuit for a corona discharge device in which the high voltage to the corona wire is electronically controlled in response to an error voltage generated by summing a reference and a sense current. In one embodiment the sense current is proportional to the screen voltage and in another embodiment the sense current is the current to the photoconductor. In each case the sense current is isolated in a single resistor. The high voltage is adjusted by utilizing the error voltage to adjust the control voltage to the high voltage power supply.

Abstract: A line printing apparatus in which spot patterns of ink or toner particles are formed on a moving paper sheet. A modulator defined by a corona source and an electric shield which has a multiplicity of linearly arranged apertures is spaced from one side of the paper. The voltage at each aperture is individually controlled so that ions from the corona are permitted or prevented from passing through preselected apertures. The passing ions impinge certain particles in a toner particle cloud between the modulator and the one side of the paper sheet. A paper support bar is positioned on the other side of the paper and constructed of an insulator and an elongate electrode is secured to the back side of the insulator and positioned parallel to the aperture array.

Abstract: A method and device for transferring from a dye supporting strip a design to a textile web under the action of heat and a sub atmospheric pressure, the strip being pressed against the web by a difference in electrostatic charge. A charging device is used adapted to direct a very narrow beam of electrons upon the strip.

Abstract: Apparatus for treating the surface of an object by means of an electrical discharge comprises a cylindrical electrode and a knife electrode, arranged on the same side of the surface to be treated, the knife electrode being tangential to the cylindrical electrode and separated therefrom by a discharge gap through which there is a flow of gas towards the object under treatment.

Abstract: The charging device for automatic copying apparatus comprises charging wires supplied with a charge voltage at all times and a plurality of lamps disposed in the rearward position of the charging device. As turning on of the lamps can prevent the photoconductor from charging by the charging wires, a charged zone corresponding to the effective image region can be produced on the photoconductor by controlling turning on and off of the lamps.

Abstract: A corona discharge wire made of electrically conducting wire of high tensile strength to which is connected a metallic fixing element on both sides of the discharge portion. The element forms a fused mass disposed in a zone surrounding the wire and solidified around it. The fixing element may consist of two parallel pieces of wire interconnected by an annular extension.

Abstract: An electrostatic line printing process employing multilayered particle modulator comprising a layer of insulating material on one side of the insulating layer and a segmented layer of conducting material on the other side of the insulating layer. At least one row of apertures is formed through the multilayered particle modulator. Each segment of the segmented layer of conductive material is formed around a portion of an aperture and is insulatively isolated from every other segment of the segmented conductive layer. Selected potentials are applied to each of the segments of the segmented conductive layer while a fixed potential is applied to the continuous conductive layer. An overall applied field projects charged particles through the row of apertures of the particle modulator and the density of the particle stream is modulated according to the pattern of potentials applied to the segments of the segmented conductive layer.

Abstract: An arrangement is provided for advancing a sheet-material web in a path, and a device for producing corona discharges includes at least one electrode roller and at least one cooperating counter roller between which the web is compelled to pass. An edge position control controls the position of the edges of the web and includes portions of the electrode roller which serve as guides for the edges of the web.

Abstract: A corona discharge arrangement for shifting the transfer point in a xerographic machine comprising an elongated wire and a shield having a plurality of conductive segments insulated from each other. A biasing arrangement is provided for changing the bias potentials on the various segments to effect a shift in the transfer point in response to preselected conditions. The transfer point may alternatively be maintained stationary by changes in the biasing potentials in response to changes in conditions which would otherwise result in a change in the transfer point.

Abstract: An arrangement for compensating for changes in the output of a corotron due to environmental changes. The arrangement includes a control corona device and a controlled corona device, the controlled corona device located in a xerographic reproduction machine in a position to deposit charge on an imaging surface and the control device located remote from said imaging surface and inoperative to deposit charge thereon, but exposed to the same environmental conditions of pressure and temperature, etc. The control corotron is connected in electrical parallel with the controlled corotron, which may be one or all of the corotrons used in the xerographic process, so that changes in the current flow in the control corotron due to the environment effect the voltage applied to the controlled corotron to produce a more stable output therefrom.

Abstract: Apparatus for the treatment of non-conductive foils or the like by subjecting them to a corona discharge of the type including two elongated electrodes with a gap between them and means for passing the foil or other sheeting through the gap has one of its electrodes, which is preferably the positive electrode, in the form of a profiled roller. The profile of the electrode roller comprises a series of ridges with troughs between them extending along the length of the roller parallel to its axis. The second electrode is also preferably in the form of a roller which has a smooth surface and is coated with dielectric material.

Abstract: Method and apparatus for charging filaments moving along a path wherein the filaments are passed across the face of a target electrode in a sheet of moving air and a plurality of corona discharge electrodes arranged in a row extending in the direction of filament travel apply an electric charge to the filaments to separate them. The corona discharge electrodes are positioned along the filament path between the point where the filaments impinge the target electrode and the point where the air stream velocity has decreased to about the velocity of the filaments.

Abstract: An electrostatic charging apparatus in which current reaching an imaging surface from a corona discharge device is automatically regulated. A sensing means is provided to measure the charging current delivered to the imaging surface and means responsive to said measured charging current to adjust the D.C. bias of an A.C. power supply energizing the corona electrode.

Abstract: A technique for charging a dielectric surface by corona discharge is described in which the voltage applied to a stationary corona wire is steadily increased over an initial time period to cause the gradual increase in voltage level on the dielectric surface over the same time period. The voltage on the stationary dielectric surface increases with the wire voltage. The potential difference between wire and plate is kept below the sparking voltage, but above the corona current threshold voltage.After the initial phase, the dielectric surface is moved relative to the corona wire (e.g. a rotating xerographic drum). The corona wire can now be held at its high voltage without sparking between the wire and the dielectric surface.

Abstract: A corona generating device comprising a coronode, a metal screen having a shield defined by upturned integral flanges mounted thereon and a support member of insulating material.

Abstract: In an electrophotographic copying machine of the type which transfer an electrostatic latent image formed on a photosensitive element, usually comprising a conductive base and a photoconductive layer thereon, onto a recording member, an electric dust collector is provided to clean the air flowing in the vicinity of a corona discharger and the photosensitive member. In order to direct the dust-free air, there is provided an air flow passage and a blower such as a fan. The corona discharger and the electric dust collector may be constructed integrally or separately. All of the air in the copying machine may be made dust-free.

Abstract: Application of a constant density of surface charge on a dielectric medium by non-contact charging is accomplished by a rotatable charging roll having a relaxable layer surrounding a conductive axle and a protective leaky insulator overcoat layer applied to the relaxable layer. The charging roll is spaced from the dielectric medium to define an air gap of about 0.010-0.060 inch and the surface velocity of the charging roll is adjustable relative to the velocity of the moving dielectric medium. A constant current power source is coupled to the conductive axle to generate a charge buildup on the surface of the relaxable layer; part of this charge is transferred across the air gap to the surface of the dielectric medium. A blade or brush is provided to clean the charging roller as it rotates.

Abstract: Apparatus for automatically regulating the amount of charge applied to an insulating surface. In a first embodiment an electrometer measures the electrostatic potential, or charge, on the insulating surface and generates an output voltage proportional thereto. The output voltage is continuously monitored and compared in a comparison means with a reference potential, the difference therebetween corresponding to an error signal. The error signal is periodically sampled and applied to an analog incremental integrator, the output thereof being coupled to a corona generator power supply, the power supply in turn being coupled to a corona electrode. The voltage applied by the power supply to the corona electrode is of a magnitude to cause the wire to apply sufficient charge to the insulating surface to reduce the error signal to substantially zero. In a second embodiment the output of the comparison means is sampled and delayed and then coupled to the corona generator power supply.