Abstract:
A multicolor image forming apparatus includes a plurality of developing units and a development power supply unit. Each of the developing units includes a developing roller located at a development gap from a photosensitive body, deposits toner accommodated therein on a surface of the developing roller, and supplies the toner to the photosensitive body across the development gap. The development power supply unit applies a development bias voltage to developing rollers of the developing units, the developing bias voltage being a rectangular AC bias voltage in which a forward bias voltage and a reverse bias voltage alternate. A percentage of toner particles of the toner having diameter-charge amounts greater than a contamination limit diameter-charge amount of a toner particle is less than 5%.
Abstract:
A developer supplying apparatus can include a first chamber and a second chamber defined within a housing. Each of the first and second chambers may include an agitator disposed therein. A magnetic body may be disposed near the first chamber to receive toner from the first chamber. A controller can determine the level of developer received in the first chamber, and to based on the determined developer level control the operations of one or more of the agitators and the magnetic body in order to ensure sufficient supply of the developer in the first chamber to reduce the occurrences of image defects, such as, for example, auger marks.
Abstract:
Provided are a multi-pass image forming apparatus and an image forming method using the same. The multi-pass image forming apparatus includes a plurality of developers for forming a plurality of electrostatic latent images using toners having different polarities and colors in one development process and for forming a multi-color image in at least two development processes; an exposure unit for forming the plurality of the electrostatic latent images on a photosensitive medium; and an intermediate transferring unit for having a toner images transferred thereon from the photosensitive medium that overlap to form the multi-color image, wherein the toner image may overlap another toner image on the intermediate transferring unit.
Abstract:
A developing device to simplify a magnet of a developer delivery unit, and an image forming apparatus with the same. In the image forming apparatus comprising a photosensitive member and a developing device that includes a developing roller to supply a developer to the photosensitive member, the developing device includes a casing defining an external appearance of the developing device, a first auger section defined in the casing for agitation and conveyance of the developer, a second auger section defined in the casing and divided from the first auger section, and a developer delivery unit provided on the outside of the casing, to deliver the developer from the first auger section to the second auger section.
Abstract:
An image forming apparatus capable of collecting residual toner from the donor roller by means of a plurality of magnetic rollers and consequently, reducing the occurrences of possible ghost phenomenon caused by the toner residue. The image forming apparatus includes an image receiving member having an electrostatic latent image formed on a surface thereof, a donor roller to receive a toner and form a layer of toner on an outer circumferential surface thereof, the donor roller being arranged to oppose the image receiving member so as to develop with toner the electrostatic latent image of the image receiving member, and a plurality of magnetic rollers each to support magnetic brushes of carrier.
Abstract:
An image forming apparatus includes a plurality of developing units to form a color image using at least a two pass developing process by developing electrostatic latent image with toners having different colors and polarities when performing a first pass of the developing process, and an exposing unit to form a tri-level potential on a photosensitive medium, in which a development applied voltage applied to a second developing unit among a first developing unit and second developing unit of the plurality of developing units operating during the first pass of the developing process is divided into a development voltage Vd, a collection voltage Vc, and at least one intermediate voltage Vn. The intermediate voltage Vn is selectively applied to one of the developing unit during a development voltage Vd applied time during which the second development voltage Vd is applied to the developing unit and during a collection voltage Vc applied time during which the collection voltage Vc is applied to the second developing unit to control one of the development voltage applied time and the collection voltage applied time without changing the other one of the development voltage applied time and the collection voltage applied time.
Abstract:
An electrophotographic image forming apparatus includes a color image forming portion to transfer a color toner to a printing medium to form a color toner image, a fusing unit to fuse the color toner image on the printing medium, a transparent image forming portion to transfer a transparent toner to the printing medium and being detachable, and a guide member to move into a first location in which the printing medium passing the color image forming portion is guided to the fusing unit and a second location in which the printing medium is guided to the transparent image forming portion.
Abstract:
Provided are a multi-pass image forming apparatus and an image forming method using the same. The multi-pass image forming apparatus includes a plurality of developers for forming a plurality of electrostatic latent images using toners having different polarities and colors in one development process and for forming a multi-color image in at least two development processes; an exposure unit for forming the plurality of the electrostatic latent images on a photosensitive medium; and an intermediate transferring unit for having a toner images transferred thereon from the photosensitive medium that overlap to form the multi-color image, wherein the toner image may overlap another toner image on the intermediate transferring unit.
Abstract:
An image forming apparatus includes a photosensitive member and a developing device. The developing device includes a developing roller to supply a developer to the photosensitive member and a casing defining an external appearance of the developing device. A first auger section is defined in the casing to agitate and convey the developer, and a second auger section is defined in the casing and divided from the first auger section. A developer delivery unit is provided on the outside of the casing to deliver the developer from the first auger section to the second auger section.
Abstract:
A developer layer-regulating method and apparatus and a developing unit and image forming apparatus having the same. The developing unit includes a developing cartridge detachably mounted in a main body of the image forming device and accommodating a developer, a developing member disposed in the developing cartridge to rotate facing a photoconductor, a regulating blade having one end coming in contact with the developing member with a predetermined pressure to regulate a developer layer of the developing member, a supporting bracket disposed in the developing cartridge to support the regulating blade, a heat transferring member disposed on the supporting bracket, a cooling member disposed on the main body to face the heat transferring member and to dissipate heat transmitted from the regulating blade, and an elastic member to elastically support the cooling member so that the cooling member is urged toward the heat transferring member.