Abstract: An image forming apparatus includes a toner storage part which stores a conductive and magnetic toner, a developing part which is accommodated in the toner storage part and generates magnetism, a hollow imaging drum which comprises a drum shaft parallel with the developing part, and a plurality of electrodes to apply electric magnetism to the toner attached to the developing part, a memory installed inside the imaging drum, a drum driver which rotatably drives the imaging drum; a data receiver which receives image data, and a main controller which controls the drum driver to keep stopping the imaging drum and stores the image data received by the data receiver in the memory if printing is requested.

Abstract: A printing media supply device for use in an image forming apparatus includes a printing media supply cassette adapted to receive a stack of printing media. A pick-up roller picks up the printing media stacked in the printing media supply cassette. The pick-up roller has a pick-up member for picking up the printing media, and a rotation member for supporting the pick-up member. The rotation member has a buffer surface formed by cutting a portion of a leading edge portion thereof away. The buffer surface may be formed so as to expose side surfaces of the pick-up member. The pick-up roller applies a substantially uniform pressure to the printing media even when there is a large quantity of printing media stacked in the printing media supply cassette, and thereby minimizes multifeeding of the printing media. Accordingly, the supply of printing media is stable, improving the printing media supply efficiency.

Abstract: An image forming apparatus that can prevent a transfer belt from being polluted by used developer on a belt cleaning member is disclosed. The apparatus includes at least one photoconductor on which a developer image is formed, a transfer belt, a belt cleaning member, and a first pollution control unit. The transfer belt transfers the developer image formed on the photoconductor to an image receiving medium, and the transfer belt is rotatably supported by a driving roller and a driven roller. The belt cleaning member cleans used developer remaining on the transfer belt after the developer image is transferred. The belt cleaning member is able to move into contact with the transfer belt or be separated from the transfer belt.

Abstract: An image forming element includes a drum body including a plurality of conductive layers and a plurality of insulating layers stacked on one another in an alternate pattern, in which a portion of each of the conductive layers extends towards a cavity defined within the conductive layers to form a plurality of electrodes, and a control unit disposed in the cavity, and including a plurality of electrode pads corresponding to the electrodes to provide an electrical connection to the respective electrodes. Structure and processes to fabricate an image forming element are simplified, and fabricating cost can be reduced.

Abstract: An image forming apparatus includes a toner storage part which stores a conductive and magnetic toner, a developing part which is accommodated in the toner storage part and generates magnetism, a hollow imaging drum which comprises a drum shaft parallel with the developing part, and a plurality of electrodes to apply electric magnetism to the toner attached to the developing part, a memory installed inside the imaging drum, a drum driver which rotatably drives the imaging drum; a data receiver which receives image data, and a main controller which controls the drum driver to keep stopping the imaging drum and stores the image data received by the data receiver in the memory if printing is requested.

Abstract: An image forming apparatus having a developer controlling apparatus for a developing roller is provided to uniformly control an amount of developer deposited on the developing roller and a developer controlling method thereof. The apparatus includes a sensing part having a first sensor which senses a conductivity of a liquid developer and a second sensor which senses a density of the liquid developer. A control part controls a voltage applied to the developing roller and/or a deposit roller according to the conductivity and the density sensed by the sensing part.

Abstract: An image fixing unit for a wet image forming apparatus comprises a fixing section and a preheating means. The fixing section has a first fixing roller, and a second fixing roller which rotates in close contact with the first fixing roller to feed paper through a gap (a fixing nip) between the first and second fixing rollers. The preheating means is disposed on a feed path of the paper before the paper enters the fixing nip, and comes into contact with a non-image surface of the paper to allow the image to be exposed to the air. Either one of the first and second fixing rollers is disposed to bring a surface thereof into contact with the non-image surface of the paper before the paper passes through the fixing nip, and the fixing roller brought into contact with the paper has a heating element mounted therein.

Abstract: An image forming apparatus that can prevent a transfer belt from being polluted by used developer on a belt cleaning member is disclosed. The apparatus includes at least one photoconductor on which a developer image is formed, a transfer belt, a belt cleaning member, and a first pollution control unit. The transfer belt transfers the developer image formed on the photoconductor to an image receiving medium, and the transfer belt is rotatably supported by a driving roller and a driven roller. The belt cleaning member cleans used developer remaining on the transfer belt after the developer image is transferred. The belt cleaning member is able to move into contact with the transfer belt or be separated from the transfer belt.

Abstract: A printing media supply device for use in an image forming apparatus includes a printing media supply cassette adapted to receive a stack of printing media. A pick-up roller picks up the printing media stacked in the printing media supply cassette. The pick-up roller has a pick-up member for picking up the printing media, and a rotation member for supporting the pick-up member. The rotation member has a buffer surface formed by cutting a portion of a leading edge portion thereof away. The buffer surface may be formed so as to expose side surfaces of the pick-up member. The pick-up roller applies a substantially uniform pressure to the printing media even when there is a large quantity of printing media stacked in the printing media supply cassette, and thereby minimizes multifeeding of the printing media. Accordingly, the supply of printing media is stable, improving the printing media supply efficiency.

Abstract: A image forming apparatus having a developer controlling apparatus for a developing roller is provided to uniformly control an amount of developer deposited on the developing roller and a developer controlling method thereof. The apparatus includes a sensing part having a first sensor which senses a conductivity of a liquid developer and a second sensor which senses a density of the liquid developer. A control part controls a voltage applied to the developing roller and/or a deposit roller according to the conductivity and the density sensed by the sensing part.

Abstract: The developing unit has a developer receptacle containing liquid developer, a deposit roller rotatively disposed substantially below a surface of the liquid developer of the developer receptacle, a developing roller rotatively disposed over the deposit roller so that a part thereof submerges in the liquid developer and a metering roller rotatively disposed on a side of the developing roller over the surface of the liquid developer. The level of the liquid developer is maintained so that an angle between a first straight line joining a rotational center of the developing roller and a first intersection point where a circumferential surface of the developing roller intersects with the surface of the liquid developer below the metering roller and a second straight line joining the rotational center and a rotational center of the deposit roller is over about 20°.

Abstract: An image fixing unit for a wet image forming apparatus comprises a fixing section and a preheating means. The fixing section has a first fixing roller, and a second fixing roller which rotates in close contact with the first fixing roller to feed paper through a gap (a fixing nip) between the first and second fixing rollers that are in close contact. The preheating means is disposed on a feed path of the paper before the paper enters the fixing nip, and comes into contact with a non-image surface of the paper (a surface of the paper on which no image is formed) to allow the image to be exposed to the air. An exemplary embodiment of the preheating means is a belt that is disposed on the feed path of the paper and is supported by a preheating roller spaced a predetermined distance apart from the first fixing roller to move along an endless path, so that the belt is adapted to be fed in contact with a non-image surface of the paper.

Abstract: A developer driving apparatus which drives a plurality of developing rollers via a gear chain including pivotable gears and one way gears. A reversible driving motor is coupled to a deceleration gear which directly drives a first swing drive gear and drives a second swing drive gear via an odd number of idler gears. Each swing drive gear is rotationally coupled with a respective swing gear having a center of rotation which is pivotable about a center of rotation of the respective swing drive gear. In a first position each swing gear drives one of the plurality of rollers via a respective one way gear and in a second position, each swing gear drives another of the plurality of rollers via a respective one way gear. A solenoid activated lever moves each swing gear between respective first and second positions.

Abstract: A developer driving apparatus which drives a plurality of developing rollers via a gear chain including pivotable gears and one way gears. A reversible driving motor is coupled to a deceleration gear which directly drives a first swing drive gear and drives a second swing drive gear via an odd number of idler gears. Each swing drive gear is rotationally coupled with a respective swing gear having a center of rotation which is pivotable about a center of rotation of the respective swing drive gear. In a first position each swing gear drives one of the plurality of rollers via a respective one way gear and in a second position, each swing gear drives another of the plurality of rollers via a respective one way gear. A solenoid activated lever moves each swing gear between respective first and second positions.

Abstract: An ink for a liquid electrophotographic color printing system is optimized to reduce the lowering of image density due to wash-off, to obtain a stable over-toned color, and to have a wide reproducible color gamut. The ink includes a plurality of toners for yellow (Y), magenta (M) and cyan (C), each toner being provided in a respective one of a plurality of developing devices, and each toner having a pigment (p) for forming an image having a predetermined color, a binder (b) for binding the pigment on printing paper, a charge controller for imparting electrical properties on the toners, and a stabilizer. A carrier transfers the toners from the developing devices to a photoreceptor belt during development. The blending ratio (b/p) of the binder (b) to the pigment (p) of each toner for yellow (Y), magenta (M) and cyan (C) satisfies the following expressions: b/pyellow(Y)=5±1; b/pmagenta(M)=7±1; and b/pcyan(C)=8±1.