Abstract: Disclosed is a rotating device including: a first gear part having a first gear; a second gear part coupled to the first gear and having a second gear that rotates relative to the first gear; a third gear part coupled to the second gear and having a third gear that rotates relative to the second gear; and first and second driving units for respectively providing rotational driving forces to first and second input gear parts which are two gear parts of the first to third gear parts to determine a rotational output of an output gear part which is the remaining gear part. At least one of the first and second driving units changes the rotational speed of at least one of the first and second input gear parts to change the rotational speed of the output gear part.

Abstract: An apparatus prevents developer wraparound in a wet electrophotographic printer using wraparound preventing units. Each of the wraparound preventing units has varied diameter parts formed at both ends of a developing roller, and matching parts formed at both ends of a metering roller to correspond to the varied diameter parts of the developing roller. Since the varied diameter parts and the matching parts are respectively installed at both ends of the developing roller and the metering roller, developer wraparound is not generated in the developing roller and a photosensitive roller during development.

Abstract: A wet electrophotographic printer includes a developing chamber communicating with an inlet of a first nip between a developing roller and a deposit roller to supply a liquid developer into the first nip therebetween, a developer storing chamber communicating with an inlet of a second nip between the developing roller and a metering roller to withdraw the liquid developer of a low density generated at the second nip during a development, and preventing the liquid developer of the low density from being supplied to the first nip, and a developer supply unit disposed below a partition to supply the liquid developer from the developer storing chamber into the developing chamber. The liquid developer of the low density generated at the second nip is not directly supplied to the first nip, but is supplied after being withdrawn to the developer storing chamber and mixed therein.

Abstract: A developer unit for a wet-type color image forming apparatus. The developer unit includes a developer bath filled with a liquid developing agent to a predetermined depth, and a developing roller that develops an electrostatic latent image formed on a photoreceptor to correspond to an original image by supplying the liquid developing agent while being partially immersed in the liquid developing agent. The developer unit further includes a cleaning roller that cleans the surface of the developing roller, a depositing roller that deposits the liquid developing agent onto the cleaned surface of the developing roller, and a metering roller that adjusts the thickness and concentration of the liquid developing agent deposited onto the surface of the developing roller by the depositing roller to suitable levels to develop the electrostatic latent image. The developer unit also includes a developer cartridge that supplies the liquid developing agent into the developer bath.

Abstract: A wet electrophotographic printer includes a developing chamber communicating with an inlet of a first nip between a developing roller and a deposit roller to supply a liquid developer into the first nip therebetween, a developer storing chamber communicating with an inlet of a second nip between the developing roller and a metering roller to withdraw the liquid developer of a low density generated at the second nip during a development, and preventing the liquid developer of the low density from being supplied to the first nip, and a developer supply unit disposed below a partition to supply the liquid developer from the developer storing chamber into the developing chamber. The liquid developer of the low density generated at the second nip is not directly supplied to the first nip, but is supplied after being withdrawn to the developer storing chamber and mixed therein.

Abstract: A liquid developer imaging system and a method using the system for developing an image, including a cartridge for containing a developing solution; a developing container for receiving the developing solution supplied from the cartridge via a predetermined supply line; a developing roller partly submerged in the developing solution contained in the developing container, installed to be rotated facing a photosensitive object; and a metering blade for scraping off the developing solution coated on the surface of the developing roller to a predetermined thickness, is provided. According to the system, a developing supply structure can be considerably simplified because a high-density developing solution is directly used in developing an image without a process of diluting the solution, and an image can be developed to have high definition because the concentration of the developing solution coated on the developing roller is regularly controlled by a metering blade.

Abstract: A liquid image forming apparatus including a developing portion in which ink is maintained at a uniform level so that the developing roller is dipped at a predetermined level, an ink reservoir in which ink supplied to the developing portion is stored, and an ink supplying unit to supply ink stored in the ink reservoir to the developing portion. The developing portion and the ink reservoir are provided in one developing container, and the ink supplying unit which supplies ink to the developing portion from the ink reservoir is provided in the liquid image forming apparatus.

Abstract: A liquid image forming apparatus including a developing portion in which ink is maintained at a uniform level so that the developing roller is dipped at a predetermined level, an ink reservoir in which ink supplied to the developing portion is stored, and an ink supplying unit to supply ink stored in the ink reservoir to the developing portion. The developing portion and the ink reservoir are provided in one developing container, and the ink supplying unit which supplies ink to the developing portion from the ink reservoir is provided in the liquid image forming apparatus.

Abstract: An apparatus prevents developer wraparound in a wet electrophotographic printer using wraparound preventing units. Each of the wraparound preventing units has varied diameter parts formed at both ends of a developing roller, and matching parts formed at both ends of a metering roller to correspond to the varied diameter parts of the developing roller. Since the varied diameter parts and the matching parts are respectively installed at both ends of the developing roller and the metering roller, developer wraparound is not generated in the developing roller and a photosensitive roller during development.

Abstract: A liquid electrophotographic printer employs a continuously circulating photoreceptor web having a non-image region with a potential higher than an image region. A laser scanner forms a latent electrostatic image in the image region, and a development unit develops the latent image using an ink having toner particles dispersed in a liquid carrier. The development unit includes a developer roller with a surface potential in between that of the image and non-image region for forming the toner image by attaching the toner particles to the image region; a toner removal roller with a surface potential between that of the image and non-image regions after they pass through the developer roller, for removing toner particles remaining in a liquid carrier film in the non-image region; and a squeeze roller with a surface potential higher than any of the foregoing, for squeezing the liquid carrier out of the toner image by compression.

Abstract: An ink pollution prevention device in a wet electrophotographic printer, for preventing a developer from polluting a photoreceptor and peripheral devices by flowing out at the ends of a development roller, a squeegee roller, and a cleaning roller, is provided with a pair of ink stoppers mounted around a shaft of each roller in a symmetrical manner with each other. Each ink stopper has a plurality of peaks and recesses which form a continuous helical shape in an opposite helical direction from the other ink stopper. The helical direction of the ink stopper is formed to permit the ink in the ink stopper to flow toward the center of the rollers when the rollers are rotated.

Abstract: A liquid developer imaging system and a method using the system for developing an image, including a cartridge for containing a developing solution; a developing container for receiving the developing solution supplied from the cartridge via a predetermined supply line; a developing roller partly submerged in the developing solution contained in the developing container, installed to be rotated facing a photosensitive object; and a metering blade for scraping off the developing solution coated on the surface of the developing roller to a predetermined thickness, is provided. According to the system, a developing supply structure can be considerably simplified because a high-density developing solution is directly used in developing an image without a process of diluting the solution, and an image can be developed to have high definition because the concentration of the developing solution coated on the developing roller is regularly controlled by a metering blade.

Abstract: A liquid electrophotographic printer employs a continuously circulating photoreceptor web having a non-image region with a potential higher than an image region. A laser scanner forms a latent electrostatic image in the image region, and a development unit develops the latent image using an ink having toner particles dispersed in a liquid carrier. The development unit includes a developer roller with a surface potential in between that of the image and non-image region for forming the toner image by attaching the toner particles to the image region; a toner removal roller with a surface potential between that of the image and non-image regions after they pass through the developer roller, for removing toner particles remaining in a liquid carrier film in the non-image region; and a squeeze roller with a surface potential higher than any of the foregoing, for squeezing the liquid carrier out of the toner image by compression.

Abstract: A photosensitive belt cartridge includes a cartridge body substantially in the shape of an ovoid whose one end is open to receive the photosensitive belt in an endless track thereto. A plurality of spring plates, whose respective ends are fixed on ends of inner wall of the cartridge body, are arranged on the inner wall of the cartridge body along the endless track of the photosensitive belt at certain intervals, for supporting the photosensitive belt in cooperation with the inner wall of the cartridge body. An inner cover is used which is disposed at an open portion of the cartridge body for supporting edges of the photosensitive belt, and also for supporting the ends of the plurality of spring plates, for preventing partial loosening of the photosensitive belt. Further, the cartridge body includes a guiding rail formed on the upper surface, which has a pair of outwardly-bent locking ribs which are slidably fit into the advancing rail of the belt unit.

Abstract: An ink pollution prevention device in a wet electrophotographic printer, for preventing a developer from polluting a photoreceptor and peripheral devices by flowing out at the ends of a development roller, a squeegee roller, and a cleaning roller, is provided with a pair of ink stoppers mounted around a shaft of each roller in a symmetrical manner with each other. Each ink stopper has a plurality of peaks and recesses which form a continuous helical shape in an opposite helical direction from the other ink stopper. The helical direction of the ink stopper is formed to permit the ink in the ink stopper to flow toward the center of the rollers when the rollers are rotated.

Abstract: There are provided a method for controlling the mode of a developing station of a liquid electrophotographic printer and a development roller driving apparatus therefor. In the controlling method, a printing mode, a drip line removal mode and a home mode are sequentially performed, and a development roller is subjected to racing in the home mode to be cleaned. Since the development roller is cleaned in the home mode in which the development roller is spaced apart from a photosensitive belt, the photosensitive belt is not contaminated by the development roller while cleaning the development roller. Also, the cleaning of the development roller is performed after completing a drip line removal mode, so sufficient cleaning time can be obtained.

Abstract: A squeegee roller cleaning apparatus of a liquid electrophotographic printer includes a squeegee roller and a cleaning roller. The squeegee roller is mounted to be operative for movement in order to selectively contact a photoreceptor web circulating along an endless path. The cleaning roller includes at least one blade member that is spirally twisted on the outer circumference of a rotary rod so as to contact the squeegee roller by the movement of the squeegee roller to remove a hold-up volume of developer. Thus, contamination of the photoreceptor web and the transfer roller can be reduced so that the quality of the printed image can be improved.

Abstract: A squeezing apparatus of a liquid electrophotographic printer includes a squeezing roller for squeezing out and removing the carrier from a developer which is applied on a photosensitive belt by its passive-rotational movement while being pressed into tight contact with the photosensitive belt at a certain pressure together with a squeezing backup roller, a squeezing brush selectively coming in contact with the outer circumference of the squeezing roller, for cleaning the squeezing roller by being rotated by a separate driving section, and a squeezing roller slip prevention mechanism disposed on both ends of a shaft of the squeezing roller to come in tight contact with the squeezing backup roller during the pressing of the squeezing roller, for preventing any occurrence of slip of the squeezing roller with respect to the photosensitive belt.

Abstract: A transfer jam detecting apparatus for a wet type electrophotographic color printer capable of detecting various kinds of jams occurring at a transfer roller, including: a printed matter entrance sensor disposed on a front side of a transfer roll, for detecting an entrance of a printed matter into the transfer roll; a feed roll disposed by a shaft to be rotated in either direction on a transfer section printed matter guide disposed on a rear side of the transfer roll, the feed roll being passively rotated by the conveyed printed matter; a pressing roll assembly disposed on an upper portion of the feed roll, for pressing the printed matter in a manner that the feed roll is passively rotated by the conveyed printed matter; and feed roll rotational direction detecting section for detecting the presence of a jam by detecting the rotation and rotational direction of the feed roll.

Abstract: An apparatus for driving a squeegee roller of a liquid electrophotographic printer including a squeegee gear coaxially installed at one shaft end of the squeegee roller, a driving gear installed such that in a state where the squeegee roller contacts the photoreceptor belt, the center of the rotation shaft thereof is positioned on a plane perpendicular to the elevating direction of the squeegee roller and passing through the center of the rotation shaft of the squeegee roller, to be engaged with the squeegee roller, and a driving source having an output shaft for rotating the driving gear to drive the squeegee roller to rotate in a reverse direction to the circulating direction of the photoreceptor belt.