Abstract: An object of the present invention is to provide a compact developing device. The present invention provide a developing device detachably attachable to an image forming apparatus, which has a developer carrying member, a developer regulating member, a conductive support member, a driving gear, a first electrode member which is provided at a driving side of the developer carrying member and to which developing voltage is applied and which is electrically communicated with the conductive support member, and a second electrode member for electrically communicating between the conductive support member and a non-driving side of the developer carrying member.

Abstract: A jump monocomponent development arrangement includes a dielectric photoreceptor belt having an image-bearing surface on one side and a conductive surface on the other side with a thickness in the range from 30 microns to 50 microns and an electrostatic charge image on the image-bearing surface has a contrast potential of 1000 to 2000 volts. Toner particles with an average diameter in the range from one micron to 20 microns are transferred from a developer roll to the electrostatic charge image using a bias potential in the range from 500 volts to 1500 volts across a development gap in the range from 100 microns to 500 microns. The difference between the maximum development voltage and the threshold development voltage is less than the contrast potential.

Abstract: In a xerographic printer, the use of traveling wave toner transport devices to deliver toner from the individual single color toner sumps to an intermediate traveling wave belt by utilizing traveling wave roll-type devices, and the traveling wave belt to carry the combination of toners to the photoreceptor. The toner could be composed of two or more toner color particles which are used as a custom color. The traveling wave transport belt mixes the two or more colors while transporting them, so that pre-mixing a custom color, and delivering it separately to the photoreceptor, is not necessary, thus enabling the use of an ordinary CMYK color printer to be used to print custom colors.

Abstract: A multicolor imaging apparatus utilizes a recording medium adapted to having a plurality of latent electrostatographic images defined by image charge potential areas and background charge potential areas. The recording medium moves in a process direction such that an image is recorded on the recording medium and then developed at a plurality of development stations. At least one of the development stations includes not less than two development housings, with each such housing including at least one donor roll, which is electrically biased.

Abstract: The present invention provides a developing apparatus that has a developing frame having an opening portion a developer carrying member provided in the opening portion and adapted to carry developer a developer charging member contacted with the developer carrying member and adapted to charge the developer carried by the developer carrying member, the developer charging member being allowed to be applied voltage and a holding member provided at a longitudinal end portion of the developing frame and adapted to hold the developer carrying member and the developer charging member.

Abstract: This invention relates to a non-contact developing method for applying a driving voltage, which is an AC voltage superimposed on a DC offset voltage, to a non-contact developing roller to develop toner, and which prevents the selective developing phenomenon from occurring. The velocity ratio between the flying velocity of toner with a large particle size and the flying velocity of toner with a small particle size changes according to the driving frequency f of the AC voltage (45) applied to the developing roller, so by setting the driving frequency f of the AC component within a range where selective developing of the toner does not occur, it is possible to effectively prevent the selective developing phenomenon from occurring.

Abstract: A developing device of an image forming apparatus using a two-component developer including toner and carrier includes a developer stirring device to stir the developer to change the toner of the developer, a developing sleeve to rotate and to carry on its surface the developer, and a conductive doctor blade or configured to regulate a thickness of the developer on the developing sleeve. The doctor blade is either grounded or receives a voltage of an electric polarity opposite to that of the toner. An electric potential of the developing sleeve is set to a same electric polarity as that of the toner, and the toner is moved toward a latent image formed on a photoconductor of the image forming apparatus so as to adhere to the latent image by an electric field formed between the developing sleeve and the latent image on the photoconductor.

Abstract: A conductive contact member 5 is disposed to come into contact with a developer carrying member 4 at the upstream side of a developing region 9 with respect to the developer conveying direction. Voltage applying members 11, 12 and 13 are also provided for applying the developer carrying member 4 with a predetermined direct voltage as a developing voltage, applying the contact member 5 with a direct voltage which has the same polarity as the developing voltage and has an absolute value larger than the developing voltage, and applying between the developer carrying member 4 and the contact member 5 an alternating voltage. A ratio t1/t2 of a time t1 for applying a voltage of absolute value larger than that of a center voltage of the alternating voltage to a time t2 for applying a voltage of absolute value smaller than that of the center voltage of the alternating voltage satisfies a relation of t1/t2>1.

Abstract: A developing apparatus includes a developer bearing member for bearing and carrying developer to a developing area. A developer is borne on the developer bearing member, wherein the developer has a weight average particle size not exceeding 6.5 &mgr;m and contains an external additive of a charging polarity opposite to that of the developer. A voltage application device applies a voltage to the developer bearing member, wherein the voltage including at least a first voltage V1 for acting on the developer in a direction from the developer bearing member toward an image bearing member and a second voltage V2 for acting on the developer in a direction from an image bearing member toward said developer bearing member, and a charged potential VL of the image bearing member, a latent image potential VD a distance H between the developer bearing member and an image bearing member, and wherein the voltages V1 and V2 satisfy a following relationships: |V1−VL|/H≦3.

Abstract: An apparatus for developing a latent image recorded on an imaging surface, including a donor member, spaced from the imaging surface, for transporting toner on the surface thereof to a region opposed from the imaging surface, the donor member includes an electrode array on the outer surface thereof, the array including a plurality of spaced apart electrodes extending substantial across width of the surface of the donor member; loading toner onto the donor member; a multi-phase voltage source operatively coupled to the electrode array, the multiphase voltage source generating a waveform which creates an electrodynamic wave pattern for moving toner particles of one polarity to and from a development zone and preventing toner particles of the opposite polarity from moving on to the development zone.

Abstract: In a xerographic printing apparatus wherein a development field is maintained between the photoreceptor and a donor member, there is always a danger of arcing across the field, particularly at high elevations. An arcing-avoidance system interacts with the print quality control system of a printing apparatus, to monitor the biases within the apparatus being demanded at various times by the control system. If a bias consistent with arcing conditions is approached, the arcing-avoidance system constrains the control system to avoid the arcing conditions. The arcing-avoidance system accepts as an input the elevation of a particular printing apparatus.

Abstract: A developing apparatus according to the present invention comprises a developer carrying member for holding a developer and introducing the developer into a developing area opposite to the image carrying member at a required distance; a voltage applying device for applying an AC voltage to the developer carrying member; and a resistor inserted between the developer applying device and the developer carrying member, the AC voltage applied to the developer carrying member from the voltage applying device through the resistor being composed of a rectangular wave, and a time period during which a voltage, which is exerted in the direction in which the developer is fed to the image carrying member, in the AC voltage is less than 50% of a time period during which the AC voltage is exerted.

Abstract: The laser printer 1 comprises a CPU 61 for controlling each components, a ROM 62 for storing control programs, a control circuit 66 constituted of ASIC and the like, a high-voltage power circuit 67 for applying high bias voltage to a developing roller 27, a DC power circuit 69 for applying bias voltage to a toner supply roller 31, a constant-current control device 68 for conducting a constant-current control with respect to the DC power circuit 69.

Abstract: A system and method for applying electrically charged non-magnetic toner to an image device, and subsequently to a moving substrate, provides precise level control, proper control of the electrical charge of the toner, minimization of dusting problems, and maximum evenness of the toner layer. First and second fluidized toner beds have the toner in them charged using corona sources. The second bed maintains a level of toner above the level in the first bed, and a spillway-defining restraining dam is disposed between the beds so that the toner above the level desired in the second bed spills over the restraining dam into the first bed, allowing very precise control of the level of toner in the second bed. Toner transfer mechanisms (such as rotating conductive cylinders) transfer toner from the first bed to the second bed, and from the second bed to the image device. Scrapers scrape excess toner from the rotating cylinders so that it falls back into either the first or second bed.

Abstract: An apparatus for developing a latent image recorded on an imaging surface, including a housing defining a chamber for storing a supply of developer material comprising toner; a donor member, spaced from the imaging surface, for transporting toner on the surface thereof to a region opposed from the imaging surface, said donor member includes an electrode array on the outer surface thereof, said array including a plurality of spaced apart electrodes extending substantial across width of the surface of the donor member; first and second discrete vibrating members in contact with said donor member, for applying first and second discrete high frequency vibratory energy to said donor member; a multi-phase voltage source operatively coupled to said electrode array and said vibrating members, wherein the phase of said multi-phase voltage source being shifted with respect to each other such as to create an electrodynamic wave pattern for moving toner particles along said electrode array and driving said vibrating memb

Abstract: A low-friction single component development apparatus for developing electrostatic latent images on an image bearing surface is provided. It includes a sump containing a supply of developer material particles; a moveable donor member assembly including a donor member for transporting developer material particles through a development zone; a first combination of AC and DC biases for charging developer material particles in the sump resulting in charged developer material particles having a desired polarity and charge distribution; a second combination of AC and DC biases for providing fringe electric fields for depositing particles of the charged developer material particles onto the donor member; devices for forming a developer material cloud within the development zone for image development; and an electrostatic filtering zone located upstream of the development zone for electrostatically removing wrong-sign charged developer material particles from the donor member.

Abstract: Toner charging and/or delivery systems and methods charge and deliver charged toner particles to an image development zone without using carrier particles. Toner particles for imaging process are charged by filling the grooves or cups of a gravure member with uncharged toner particles and charging the toner particles in the grooves or cups using a corona discharge device. The charged toner particles are then transported directly or indirectly to an imaged photoreceptor, where the charged toner particles are used to develop a latent electrostatic image on the imaged photoreceptor. The developed image is then transferred to a copy sheet and permanently fused to the copy sheet.

Abstract: Disclosed is a toner support for preventing occurrence of an image failure such as stain, uneven image density, and fogging on a white image as much as possible, thereby certainly forming a high quality image enough to keep up with formation of a color image. The toner support is characterized in that the maximum value of a surface potential of the toner support, which is measured after an elapse of 0.35 sec since the surface of the toner support is charged by generating a corona discharge by means of applying a voltage of 8 kV to a corona discharger disposed apart from the surface of the toner support by 1 mm, is in a range of 90 V or less, and that the absolute value of a surface potential decay rate of the toner support, which is measured at an elapse of 0.2 sec after charges are imparted on the surface of the toner support by generating a corona discharge by means of applying a voltage of 8 kV to a corona discharger disposed apart from the surface of the toner support by 1 mm, is in a range of 0.

Abstract: A developing apparatus includes a developer carrying member, provided in an opening of a developer container, for carrying a developer to a developer position. A leakage preventing member is supplied with a voltage from a voltage source having the same polarity as a charging property of the developer to prevent leakage of the developer from a longitudinal end of the developer carrying member. The developing apparatus is movable between an operative position for development where the voltage is capable of being applied and an inoperative position where the voltage is incapable of being applied. A discharging device electrically discharges the leakage preventing means after a start of movement from the operative position toward the inoperative position and before returning to the operative position. A capacitor, electrically is connected to the leakage preventing member, for accumulating electric charge supplied from said voltage source.

Abstract: An image forming apparatus includes an image bearing member, a developer carrying member for carrying thereon a developer to transport the developer to a developing zone, and a regulation member provided in touch with the surface of the developer carrying member to regulate coat weight of the developer carried thereon. The image bearing member includes a conductive substrate and a photosensitive layer formed thereon, and the photosensitive layer contains at least one polycarbonate resin (I) having a viscosity-average molecular weight not more than 1.5×104 and at least one polycarbonate resin (II) having a viscosity-average molecular weight more than 1.5×104, the polycarbonate resin (I) being contained in a proportion of from 30% by weight to 95% by weight based on the total weight of the polycarbonate resins (I) and (II). On the developer carrying member, the developer is in a coat weight not more than 1.5 mg/cm2 at the developing zone after its regulation by the regulation member.

Abstract: An image forming apparatus includes an image bearing member for bearing an electrostatic image; a developer carrying member for carrying a developer and for forming a developing zone with the image bearing member, wherein the developer is externally added with additive having a charging polarity opposite from that of the developer; a voltage applying device for applying a developing voltage to the developer carrying member; voltage a control device for controlling the developing voltage so as to change force for directing the additive toward a non-image portion of the image bearing member in accordance with a number of image forming operations.

Abstract: A developing apparatus according to the present invention for developing an electrostatic latent image formed on an image carrying member has a developer carrying member arranged opposite to an image carrying member and holding a developer, and a voltage applying device applying an AC voltage to the developer carrying member, wherein the AC voltage has a first peak potential and a second peak potential, the first peak potential being a peak potential on the side of development for supplying the developer to the image carrying member, the second peak potential being a peak potential on the side of recovery for returning the developer to the developer carrying member, and a voltage waveform of the AC voltage always has two straight line portions which differ in slopes while changing from the first peak potential to the second peak potential and/or from the second peak potential to the first peak potential.

Abstract: A toner supply bias voltage that is a vibrating voltage comprising an a.c. voltage and a d.c. voltage is applied to a toner supply roller. The d.c. voltage of toner supply bias voltage is changed in dependence upon a variation in the value of developing bias voltage. The lowering in the density at the leading end part of an image, the lowering in the density at the trailing end part of an image, and the uneven developing can be eliminated by satisfying the relationships100.ltoreq..vertline.VB.vertline..ltoreq..vertline.VSR.vertline.,2(.vertline.VSR-VB.vertline.+50).ltoreq..vertline.VPP.vertline..ltoreq.2.ve rtline.VSR.vertline. andf.gtoreq.v/lare satisfied, where VB is a developing bias voltage (unit: Volt), VSR is a d.c. voltage of the toner supply bias voltage (unit: Volt), VPP is a peak-to-peak value of the a.c.

Abstract: The inventive developing apparatus 10 includes: a developing roller 15 rotating in a predetermined direction; a regulating blade 16 for regulating layer thickness of developer G1 on the developer roller; 15; and a supplying roller 17 disposed at the upper stream than the regulating blade 16 while the developing apparatus 10 rotates in the predetermined direction. Further, the developing apparatus 10 rotates the developing roller 15 in the reverse direction for the predetermined direction during a predetermined period. Thereby, agglomerates stopping at the space between the developing roller 15 and the regulating blade 16 escape therefrom and developer leak and defective supply of developer and the like are cleared away. While the developing roller 15 is rotated in the reverse direction, the agglomerates escaped from the space come to contact with the supplying roller 17 and are crashed by press of the developing roller 15 and the supplying roller 17.

Abstract: An apparatus for developing a latent image recorded on an imaging surface, including a housing defining a chamber storing a supply of developer material including toner; a donor member, spaced from the imaging surface, for transporting toner on the surface thereof to a region opposed from the imaging surface, said donor member includes an electrode array on the outer surface thereof, said array including a plurality of spaced apart electrodes extending substantial across width of the surface of the donor member; a multi-phase voltage source operatively coupled to said electrode array, the phase being shifted with respect to each other such as to create an electrodynamic wave pattern for moving toner particles to and from a development zone; and a charging device for charging toner on the surface of said donor member.

Abstract: A developer and development process for use in an image formation apparatus employing electrophotographic developing technology. In the developer, a reset roll may be positioned around the toner feeding roll so as to come into contact with a toner feeding roll, thus getting the remaining toner from the surface of the toner feeding roll so as to clean the toner feeding roll. A cleaning blade is positioned with its edge coming into contact with the surface of the reset roll, thus removing the remaining toner from the reset roll. The developer almost completely prevents any deterioration of expected operational function of a toner feeding roll even when the developer is used for a lengthy period of time, thereby effectively preventing any reduction in the image quality of processed papers due to such a deterioration of the toner feeding roll's operational function.

Abstract: An apparatus for removing developer from a developer carrier includes a developer-charge-eliminating means including a first elastic member. The first elastic member is electrically conductive and contacts the developer carrier with an uneven surface. Preferably, the uneven surface includes exposed cells of a foamed body. The uneven surface of the first elastic member insures that sufficient contact and frictional resistance is applied to excess developer on a developer carrier. Preferably, the first elastic body is backed by a backing member which is more flexible than the first elastic member. The flexible second elastic body further insures that the charge-eliminating member sufficiently contacts the developer carried by the developer carrier even with extended use.

Abstract: A development device according to the invention has an arrangement wherein a developer carrying member holding a toner thereon and an image bearing member with an electrostatic latent image formed thereon oppose each other across a predetermined gap therebetween, and a power unit applies an alternating voltage to the gap for supplying the toner from the developer carrying member to the image bearing member, the development device satisfying any one the following conditions: ##EQU1## where a (.OMEGA.) denotes a resistance component of an impedance (a+b.multidot.i) of the developer carrying member, -b (.OMEGA.) denotes a capacitative reactance component of the impedance thereof, and f (Hz) denotes a frequency of the alternating voltage.

Abstract: A developing device for developing an electrostatic latent image on a photoconductive member has a developing roller that bears a one-component developer on its surface and develops the electrostatic latent image by contacting the photoconductive member; a supply roller for supplying developer to the developing roller; and a blade that contacts the developing roller so as to regulate a layer thickness of the developer supplied by the supply roller, wherein supposing that the developer has a volume-average particle size represented by Dbk, the developer at this time being maintained on the developing roller as a layer that has been supplied by the supply roller and again formed so as to have a predetermined thickness by the blade after the developing roller, on which the developer was formed as a layer having a predetermined thickness, carried out a black-image developing process, and supposing that the volume-average particle size of the developer is Dwt, the developer at this time being maintained on the dev

Abstract: A toner layer forming device is used for a developing device of an electrophotographic device, in which a toner holding member rotates in a predetermined direction while holding on its surface a nonmagnetic toner containing a detachant. A rotary toner layer control member whose surface rotates in the reverse direction to the surface of the toner holding member while contacting the surface with the surface of the toner holding member is provided in order to control the nonmagnetic toner layer. A toner removing member partially contacts with the surface of the rotary toner layer control member in order to scrape off the nonmagnetic toner held on the rotary toner layer control member, so that the toner on the rotary toner layer control member can be removed smoothly and a stable toner layer can be formed.

Abstract: A method for separately retrieving used developing material on a developing roller and supplying new developing material, while balancing the retrieval of the used developing material with the supply of the new developing material in accordance with an increase in the number of papers being printed. The method is directed to retrieving and supplying developing material in an electrophotography forming apparatus which includes a developing roller, a retrieval roller and a supply roller. The method includes the steps of: rotating the retrieval roller connected to the developing roller in the same direction as the direction of rotation of the developing roller; and applying voltages to the developing roller, the retrieval roller and the supply roller in accordance with a predetermined relationship.

Abstract: The object of the invention is to certainly remove and certainly recover the charged toner remaining on a developing roller after development. A single component toner which is delivered to the developing roller via a toner-supplying roller is made into a relatively thin layer of a predetermined thickness with a charging plate and is frictionally charged with a given quantity of electric charge. Subsequently, the toner is adhered on a photoreceptor drum along by the electrostatic latent image to develop an image at the developing region at which the developing roller comes into contact with the photoreceptor drum. After development, the electric charge of the toner layer on the developing roller is removed with an electric-charge-removing sheet. The toner after development is recovered into a toner hopper via the toner-supplying roller.

Abstract: A developing device used in an image forming apparatus has a developing roller at a lower opening of a toner hopper, and the developing roller contacts a photosensitive drum to form a developing portion therebetween. The hopper stores nonmagnetic toner and is provided with a toner stirring member and a toner feed roller being in press-contact with the developing roller in a lower part of the hopper. A doctor blade contacts a circumferential surface of the developing roller on an upstream side of the developing portion in a rotation direction of the drum. A conductive scooping sheet contacts the circumferential surface of the developing roller on a downstream side of the developing portion. A residual toner not used to develop a latent image on the drum and left on the developing roller is passed under the sheet into the hopper with the rotation of the developing roller.

Abstract: A switching element and a protective resistance are connected between a developing roller and a developing bias source. A switching element switches on and off a connection between the developing roller and the developing bias source. A protective resistance is connected to the switching element in series. There is a controller and a bias stabilizer. The controller switches on the switching element when a developing bias voltage is to be applied to the developing roller and switches off the switching element when the developing roller is caused to be in an electrically floating state without applying the developing bias voltage, and which bias stabilizer is disposed between the developing roller and a ground and maintains a predetermined stable voltage only when the switching element is switched on. The structure enables a high-quality image to be formed with a low power consumption.

Abstract: A developing cartridge for developing a latent image formed on an electrophotographic photosensitive member, which is detachably mountable relative to a main assembly of an electrophotographic image forming apparatus, the developing cartridge includes a cartridge frame; a developing roller for developing the electrostatic latent image formed on the electrophotographic photosensitive member; toner accommodating portion for accommodating toner to be used for development by the developing roller; a driving force receiving member for receiving driving force for rotating the developing roller, from the main assembly of apparatus when the developing cartridge is mounted to the main assembly, wherein the driving force receiving member is exposed from a portion of the cartridge frame, provided at one longitudinal end portion; a developing bias contact for receiving a developing bias to be applied to the developing roller from the main assembly of the apparatus, when the developing cartridge is mounted the main assemb

Abstract: To prevent scattering of toner when an image forming operation is started and ended in a developing process using one-component toner, a rotatable developing roller in contact with a photosensitive member carrying a static latent image, which is used to carry and feed one-component toner, is provided in a developing tank containing one-component toner. Initially, toner is fed to a feed roller, then passed through a toner restricting member which is pressed against the developing roller to restrict the amount of toner to be fed, so that a layer of toner is formed at a fixed thickness and fed into a developing area in contact with the photosensitive member. Thus a static latent image is produced on the developing roller. In this process, a developing bias voltage Va is supplied to the developing roller, a restricting voltage Vb is supplied to the toner restricting member so as to fix the thickness of the toner layer, and a supply voltage Vc is supplied to the feed roller to control the supply of toner.

Abstract: An electrophotographic developing apparatus uses a two-component developer comprising a carrier and a toner for development. The apparatus includes an intermediate roller with a non-magnetic sleeve accommodating a magnetic roller disposed between a developing roller and an agitating device for tribo-frictionally charging the carrier and the toner. After forming a magnetic brush consisting of the carrier and the toner, the toner is transferred to the developing roller by applying a first bias to the intermediate roller and the developing roller. A second bias is applied to the developing roller and an image carrier included in the apparatus to cause the toner to selectively attach to the image carrier. A third bias is applied to the developing roller and the intermediate roller to cause the toner to transfer back to the intermediate roller.

Abstract: An elastic member for pressing is provided in a prescribed location in an area where the developer carrier comes in contact with the discharging member, in order to bring the discharging member into contact with the developer carrier so that mechanical peeling of the residual developer on the developer carrier is not caused, and the discharging member is provided with a bias power supply for setting bias in a direction imparting to the discharging member a force for electrically drawing the residual developer on the developer carrier away from the developer carrier, and after thus reducing the electric adhesion of the residual developer to the developer carrier, the developer feed member removes the residual developer on the developer carrier in the vicinity of disjunction area or in the contact area of the developer carrier and the developer feed member, thereafter applies new developer in a developer container to the developer carrier in the vicinity of approaching area or in the contact-starting area of th

Abstract: An image forming apparatus includes an image support which supports an electrostatic latent image on a surface of the image support. A developing unit has a developing agent support which retains a developing agent, including a toner and carriers, contained in the developing unit. The developing unit converts the latent image on the image support into a toner image by causing the toner to adhere to the surface of the image support. A developing bias supplying unit supplies a developing bias voltage to the developing agent support of the developing unit, the developing bias voltage being one of a DC bias voltage and an AC bias voltage. A timer measures a non-driven period of the developing agent in the developing unit.

Abstract: An improved method for controlling the optical density of an image printed by an electrostatic printer is provided. The method compensates for optical density drift over the useful life of a toner receptacle by adjusting the voltage vector between the photoconductive belt and the toner particles. The method calculates an overall toner usage amount and adjusts the voltage vector when the amount reaches one or more predetermined values. In this manner, the present method controls the optical density of a printed image over the useful life of the toner receptacle.

Abstract: An image forming apparatus of the present invention is capable of forming an oscillation electric field in a developing region on the basis of the particle size of toner and the particle size of magnetic carrier. Assume that the oscillation electric field includes a phase for causing the toner to move toward a latent image and having a duration t.sub.1, that the electric field has a period T, that the toner has a weight-average particle size of L.sub.t, and that the carrier has a weight-average particle size of L.sub.c. Then, there hold a relation of 1.0.times.10.sup.-4 <t.sub.1.sup.2 /L.sub.t <1.0.times.10.sup.-3 ?sec.sup.2 /m! and a relation of T.sup.2 /L.sub.c <0.005 ?sec.sup.2 /m!. The apparatus insures images with uniform dots and including a minimum of noise.

Abstract: A development system including a developer transport adapted for depositing developer material on an imaging surface having an electrostatic latent image thereon, including a housing defining a chamber storing a supply of developer material including toner. A donor member is mounted partially in said chamber and spaced from the imaging surface, for transporting toner on an outer surface thereof to a region opposed from the imaging surface. The toner donor member has a magnetic assembly which includes a plurality of poles and a sleeve, enclosing said magnetic assembly and rotating about said magnetic assembly. A sensor measures a magnetic field of said donor roll at a predefined position on said donor roll. A control system generates an electric field continuously optimize the development of toner regardless of the ever changing height of the developer bed.

Abstract: A compact design for the electronic circuits to provide electrical contact to a SED roll of a segmented electrode development unit is provided. In this invention, the required high voltage and low voltage circuitry is placed on a printed flexible circuit which is folded and rolled into a cylindrical circuit to be connected to the SED roll. The flexible printed circuit has a plurality of output terminals each of which will be connected to one of the electrodes of the SED roll and a plurality of input terminals each of which will be connected to a terminal of a slip ring to receive the required electrical power.

Abstract: An apparatus for transporting charged particles in a predetermine path which includes a donor member that is adapted to move charged particles on the surface thereof in the predetermined path. The donor member includes an electrode array on the outer surface thereof; the array including a plurality of spaced apart electrodes extending substantially across width of the surface of the donor member. A multi-phase DC voltage source is operatively coupled to the electrode array, the phase being shifted with respect to each other such as to create an electrodynamic wave pattern capable of moving charged particles on the surface thereof in the predetermined path.

Abstract: A compact design for the electronic circuits to provide electrical contact to a SED roll of a segmented electrode development unit is provided. In this invention, all the required high voltage and low voltage circuitry is placed on a printed flexible circuit which is folded and rolled into a cylindrical circuit to be connected to the SED roll. The flexible printed circuit has a plurality of output terminals each of which will be connected to one of the electrodes of the SED roll.

Abstract: A hybrid jumping development system utilizing two component developer and providing an improved device for controlling developed toner mass. Toner is metered onto a donor structure and a toner cloud is formed in a development nip between the donor structure and the charge retentive surface having a latent electrostatic image thereon. The toner cloud is formed by applying an alternating potential to the donor structure so as to cause the toner particles to jump off of the donor structure. The duty cycle of the AC potential is used to control the toner cloud and thus the amount of toner developed on the charge retentive surface.

Abstract: A photographic developing apparatus which visualizes a latent image formed on an image carrier is disclosed which includes:a developing powder carrier provided so as to be opposite to the image carrier;a layer forming member for forming a thin layer of developing powder over a circumferential surface of the developing powder carrier;a charge imparting member which is provided so as to be opposite to the developing powder carrier and causes an electric field between the charge imparting member and the developing powder carrier; andan electrification control member which is interposed between the charge imparting member and the developing powder carrier, and limits an ionization area caused by electric discharge in the electric field by receiving an intermediate electric potential between the electric potential of the charge imparting member and the electric potential of the developing powder carrier.

Abstract: A developing device capable stable production of halftone image having excellent texture while maintaining suitable image density by utilizing an AC electric field between a developer-carrying member and an image-carrying member and providing a rest period wherein the AC electric field is not active so as to develop electrostatic latent image formed on the image carrying member.

Abstract: The present invention is directed to a developing device using a developer carrying member in which an insulating layer is formed on the surface of a conductive base substrate for regulating, in conveying a developer to a developing area opposite to an image carrying member with it being held on the surface of the developer carrying member, the amount of the developer conveyed to the developing area upon pressing a regulating member against the surface of the developer carrying member, wherein a regulating member in which a dielectric layer satisfying the following relationship (1) is formed on an electrical conductive member is used as the regulating member, to press the dielectric layer against the developer carrying member:t/.epsilon..gtoreq.10 (1)where t (.mu.m) is the thickness of the dielectric layer, and .epsilon. is the relative dielectric constant of the dielectric layer.

Abstract: Cleaning effectiveness is improved, and inadequate charging of the photosensitive member due to soiling of the charging brush as well as image noise such as background fog are suppressed by a developing device capable of recovering residual toner regardless of the toner charge polarity. In an image forming apparatus provided with a developing device including a developing sleeve for developing an electrostatic latent image on photosensitive member via toner and recovering residual toner from the surface of photosensitive member, a power unit is provided for forming a direct current electric field between photosensitive member and developing sleeve during developing, and forming alternating current electric fields between photosensitive member and developing sleeve 16 during cleaning of residual toners.