Patent application number | Description | Published |
20080286015 | DEVELOPMENT DEVICE AND IMAGE FORMING APPARATUS - The development device includes a toner carrier, a toner supplier, and a surface electrical potential controller. When the toner supplier supplies toner particles to the toner carrier, the toner carrier carries toner particles to adhere to a latent image formed on the latent image carrier and has a time constant τ | 11-20-2008 |
20090016781 | DEVELOPING DEVICE, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS - A developing device comprises a latent image carrier that carries a latent image, a toner carrier opposing the latent image carrier while carrying toner to develop the latent image, and plural electrodes arranged in a prescribed direction insulated from each other on the surface of the toner carrier to create an electric field therebetween. An alternating voltage supplying device is provided to supply n number of phases (n≧2) of an alternating voltage to the plural electrodes, respectively. The alternating voltage changes the electric field to cause the toner to hop and form toner cloud on the surface of the toner carrier. The toner hopping is halted at a prescribed time period during the toner cloud formation. | 01-15-2009 |
20090035025 | DEVELOPING APPARATUS, IMAGE FORMING APPARATUS, AND PROCESS CARTRIDGE - A disclosed developing apparatus employs a flare roller that is a toner carrier in which electrodes of two different phases are provided at fine intervals. Density irregularities or scumming in a developed image due to a potential difference between the flare roller and a latent image carrier are prevented by maintaining a constant potential on the flare roller surface. A voltage is applied to the electrodes on the flare roller such that an electric field that varies with time is generated between the electrodes, whereby a toner cloud is produced by the movement or hopping of toner over the flare roller. Thereby the toner attaches to a latent image on the latent image carrier, thus developing the latent image. In one embodiment, a bias with an average potential equal to an average potential of the bias applied to the electrodes is applied to a toner layer thickness regulating member. | 02-05-2009 |
20090067879 | DEVELOPING DEVICE, PROCESS CARTRIDGE AND IMAGE FORMING APPARATUS - A developing device for a toner powder cloud development system, which can achieve high image quality and can be made compact. The developing device has a two-component development unit, a toner carrier, and an alternating current power source. The toner carrier, which is arranged opposing a latent image carrier, has a plurality of electrodes disposed in a line in a prescribed direction on the surface thereof, and mutually insulated. The alternating current power source supplies a voltage such that an electric field across the plurality of electrodes is temporally switched. The inter-electrode electric field causes the toner being carried on the surface of the toner carrier to carry out hopping, thereby forming a toner powder cloud and carrying out development. The movement speed of the latent image carrier and the linear velocity of the toner carrier are set at approximately equivalent speeds. | 03-12-2009 |
20090067889 | DEVELOPING DEVICE, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS - A developing device constituted to be capable of reliably making toner flare, and carrying out developing normally in the developing area, by preventing toner from adhering to the toner carrier. A developing device having a toner carrier which is disposed in opposition to a latent image carrier and which carries toner for developing an electrostatic latent image on the latent image carrier, the developing device including: a plurality of electrodes aligned at a predetermined interval within the toner carrier; voltage application means for applying a voltage to the electrodes so that the electric field between the plurality of electrodes varies with time, wherein the electric field between the electrodes causes the toner on the toner carrier to hop and form a cloud; and a toner adhesion prevention member that is provided upstream of a developing area where the latent image carrier is in opposition to the toner carrier and that prevents adhesion of toner to the toner carrier. According to the developing device, it is possible to prevent toner from adhering to the toner carrier, and it is possible to make the toner flare reliably. | 03-12-2009 |
20090074431 | IMAGE FORMING APPARATUS - An image forming apparatus includes a toner-layer filling-rate lowering unit that causes a toner layer of toner images to be formed on an image carrier so that the toner layer has sufficient optical transparency for exposing and the toner-layer filling rate is set relatively low; and a toner rolling rate adjusting unit that rolls the toner images at a predetermined toner rolling rate in accordance with the toner-layer filling rate when the toner images are transferred to the transferring/fixing unit. | 03-19-2009 |
20090123193 | DEVELOPMENT DEVICE AND IMAGE FORMING APPARATUS THAT USES THIS DEVICE - A development device capable of suppressing the occurrence of development defects caused by partial damage to an electrode of a toner bearing roller. The development device is provided with a first electrode layer and a second electrode layer, which are laminated so as to overlap one another in a normal direction with respect to the surface of the roller part of the toner bearing roller. A plurality of openings, which are independently arranged in a matrix in both the roller surface movement direction and an orthogonal-to-movement direction which is the direction orthogonal thereto, are provided in, of these electrode layers, the second electrode layer existing in the upper location that is closer to the roller surface, over the entire latent image bearable area of a photosensitive body in the orthogonal-to-movement direction. The toner on the surface of the roller part is caused to hop between a plurality of spots directly beneath the openings that respectively exist directly beneath the plurality of openings in the second electrode layer, and a plurality of spots between the openings that respectively exist between the plurality of openings in the second electrode layer, within the entire area of the first electrode layer which is uniformly formed in the roller circumferential direction. | 05-14-2009 |
20090257786 | DEVELOPING DEVICE, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS - A developing device includes a toner carrying member and an electric-field forming unit. The electric-field forming unit forms electric fields having different characteristics at a first area of the surface of the toner carrying member located within a developing area and a second area of the surface of the toner carrying member located out of the developing area such that a hopping height of toner at the first area is higher than that at the second area. | 10-15-2009 |
20090257791 | DEVELOPING UNIT, PROCESSING UNIT, AND IMAGE FORMING APPARATUS - A developing unit includes a brush member that includes a base member and a plurality of raisings that are erected on a surface of the base. The brush member traps toner within the raisings and causes a flicker movement in the raisings of the brush so that the toner trapped within the raisings is shaken and flown due to the flicker movement to the surface of a toner carrying member. | 10-15-2009 |
20090290901 | DEVELOPMENT DEVICE - A development device includes an open-ended housing, a rotatable roller, an array of multiple primary electrodes, a voltage source, a sealing member, and a secondary electrode. The housing accommodates toner for application to the photoconductive surface through an end opening thereof. The roller has an outer circumferential surface to deliver the toner from within the housing to a development zone. The array of multiple primary electrodes are aligned with each other on the roller surface. The voltage source applies a periodic pulse voltage to at least a subset of the primary electrodes to generate an oscillating primary electric field. The sealing member seals clearance between the roller surface and an edge of the end opening downstream from the development zone. The secondary electrode generates a secondary electric field to force the toner from the sealing member toward the roller surface to prevent premature removal of the toner. | 11-26-2009 |
20100021214 | DEVELOPING DEVICE, IMAGE FORMING APPARATUS, AND PROCESS CARTRIDGE - A toner carrying member includes a plurality of electrodes arranged in a first direction intersecting with a second direction in which its surface moves. A voltage applying unit applies a bias to the electrodes such that an electric field direction is changed temporally in an alternate manner between adjacent electrodes. An adjusting member adjusts an amount of toner carried on the toner carrying member. A toner-cloud facilitating member includes a conductive member arranged between the toner supplying member and the adjusting member in the second direction in opposite to the toner carrying member. | 01-28-2010 |
20100150615 | DEVELOPER BEARING MEMBER & DEVELOPING DEVICE WITH PLURAL LAYERS OF ELECTRODES CREATING ELECTRIC FIELD - An developer bearer conveys developer to a developing station under influence of an electric field created by an electric flux line. The developer bearer includes plural kinds of electrodes that receive different voltages from each other and collectively creates the electric flux line. The plural kinds of electrodes are arranged on different layers in a normal line of the developer bearer. The developer bearer includes an insulation layer that insulates the plural kinds of electrodes. | 06-17-2010 |
20110164892 | DEVELOPMENT DEVICE, PROCESS CARTRIDGE INCORPORATING SAME, AND IMAGE FORMING APPARATUS INCORPORATING SAME - A development device includes a developer container, a rotary developer carrier that is disposed facing the latent image carrier and including multiple outer electrodes arranged in a circumferential direction of the developer carrier, an inner electrode electrically insulated from the multiple outer electrodes, an insulation layer disposed between the inner and outer electrodes, and a surface layer overlaying the outer electrodes and electrically insulating the multiple outer electrodes from each other, a bias power source to generate electrical fields that change with time by applying a first and second bias voltages to the inner and outer electrodes, respectively, an electrical field adjuster to regulate the electrical fields in accordance with a thickness of the surface layer of the developer carrier, and a controller. | 07-07-2011 |
20120057891 | IMAGE FORMING APPARATUS - An image forming apparatus includes a latent image carrier; a latent image writer to write a latent image on the latent image carrier; a developing unit including a toner carrier having first and second electrodes insulated via an insulator member and a voltage applying unit to apply voltages to the first and second electrodes having a potential difference to generate first electric fields to cause the toner to hop from the toner carrier to the latent image carrier to develop a toner image; and a transfer unit to transfer the developed toner image to a transferring member. When alternating voltages having a same phase and same amplitude are applied to the first and second electrodes to form second electric fields between the latent image carrier and the toner carrier, the toner is discharged from the toner carrier to the latent image carrier in a toner discharge mode. | 03-08-2012 |
20120063797 | DEVELOPING DEVICE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD - An image forming apparatus includes a latent image carrier to carry a latent image, a developing device having a toner carrier with first and second electrodes to develop the latent image by transferring the toner to a developing region between the toner carrier and the latent image carrier while causing the toner to hop between the first and second electrodes and attaching the hopping toner to the latent image, a pulsed power supply to output a first periodic pulse voltage having a mean potential the same as a normal toner charge and a second periodic pulse voltage, a smoothing circuit to make the first periodic pulse voltage smooth to generate a direct voltage, and a toner layer thickness regulator member to regulate, on receiving the direct voltage, a thickness of the toner layer in a region between a toner supply position at which toner is supplied and the developing region. | 03-15-2012 |
20120063815 | DEVELOPMENT DEVICE, PROCESS CARTRIDGE INCORPORATING SAME, AND IMAGE FORMING APPARATUS INCORPORATING SAME - A development device includes a developer container; a rotary cylindrical developer carrier including an outer electrode including multiple electrode portions arranged in a circumferential direction of the developer carrier, an inner electrode provided on an inner circumferential side of the developer carrier from the outer electrode, an insulation layer disposed between the outer electrode and the inner electrode, and a surface layer; and a bias power source to apply a first bias voltage and a second bias voltage to the inner electrode and the outer electrode, respectively. The first bias power source causes an electrical potential difference that changes with time between the inner electrode and the outer electrode to cause the developer to hop on a circumferential surface of the developer carrier. At least one of the first bias voltage and the second bias voltage has a cyclic waveform in which pulse-on time is reduced. | 03-15-2012 |
20130071147 | DEVELOPMENT DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer, and a planar metal developer regulator to adjust an amount of developer carried by the developer bearer to the development range. The developer bearer includes a developer carrying range having surface unevenness, and the developer regulator includes a fixed end portion held by a regulator holder and a free end portion to contact a surface of the developer bearer. | 03-21-2013 |
20130071148 | DEVELOPMENT DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer, a planar developer regulator disposed to contact a surface of the developer bearer to adjust an amount of developer carried to the development range, and a lateral end seal to contact an axial end portion of the developer bearer. The developer bearer includes an uneven surface range having projections and recesses and including an axial center of the developer bearer and smooth surface ranges positioned outside the uneven surface range in an axial direction of the developer bearer, and the lateral end seal is disposed astride the uneven surface range and the smooth surface range of the developer bearer. | 03-21-2013 |
20130209143 | DEVELOPING DEVICE AND IMAGE FORMING APPARATUS - A developing device including: a toner bearing member configured to bear a toner on a surface of the toner bearing member and configured such that the surface thereof is rotated to supply the toner to and develop a latent electrostatic image on a surface of a latent electrostatic image bearing member in a developing region which faces the latent electrostatic image bearing member; and a regulating member configured to regulate an amount of the toner to be moved towards the developing region, wherein the surface of the toner bearing member has regularly arranged convex portions, and wherein a non-electrostatic adhesive force between the toner and the surface of the toner bearing member is less than 9.0 nN. | 08-15-2013 |
20130216250 | DEVELOPMENT DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer, and a developer regulator to adjust an amount of developer transported to the development range by the developer bearer. Multiple projections are formed in a surface of the developer bearer, and the developer bearer rotates in a reverse direction to a direction of rotation for image development while image development is not performed. The developer regulator includes a blade having a first end held by a regulator holder and a second end that contacts the multiple projections formed in the surface of the developer bearer and is disposed in a direction counter to the direction of rotation of the developer bearer for image development. | 08-22-2013 |
20130216276 | DEVELOPMENT DEVICE, AND IMAGE FORMING APPARATUS AND PROCESS CARTRIDGE INCORPORATING SAME - A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer and a developer regulator to adjust an amount of developer transported to the development range by the developer bearer. The developer bearer includes a developer carrying range having surface unevenness; and a surface of the developer bearer is coated with a coating material including a resin material and particles to roughen the surface. | 08-22-2013 |
20130216277 | DEVELOPMENT DEVICE, AND IMAGE FORMING APPARATUS AND PROCESS CARTRIDGE INCORPORATING SAME - A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer, and a developer regulator to adjust an amount of developer transported to the development range by the developer bearer. Multiple projections are formed in a surface of the developer bearer, and, in a direction in which the developer bearer rotates, a downstream end of each of the multiple projections is higher than an upstream end of the projection. | 08-22-2013 |