Abstract: A paper discharge unit for an inkjet printer which ejects a sheet on which image printing is completed by an ink cartridge out of a printer main body. The paper discharge unit for an inkjet printer includes paper discharge rollers rotatably mounted in the printer main body to feed the printing-completed sheet out of the printer main body; and paper discharge guides disposed downstream of the paper discharge rollers in a direction the sheet is fed, and guiding upward the front end portion of the sheet ejected from the paper discharge rollers to prevent the rear end portion of the sheet from being lifted. Accordingly, the front end portion of the sheet is deformed by the paper discharge guides to restrain the end portion of the sheet facing a nozzle part of the ink cartridge from being in contact with the nozzle part when the sheet is ejected, so that image printing becomes possible up to the end portion of the sheet, to thereby improve the printing efficiency of the inkjet printer.

Abstract: An inkjet printer driving a maintenance apparatus using a power to a feed roller. In the inkjet printer, the maintenance of the maintenance apparatus is started by a carriage. The maintenance apparatus includes a maintenance member which cleans and covers the nozzle of a print head, a maintenance cam which controls the maintenance member through a rotating motion, a maintenance gear which is disposed at one end of the maintenance cam and has a cut off portion in which a part of gear teeth is partially cut off in a face width direction, and a connection gear disposed on a shaft of the feed roller to be able to move in a shaft direction by the carriage and transmit the power of the feed roller. During the printing operation of the carriage, the connection gear is placed on the cut off portion, and then engaged with the teeth of the maintenance gear disposed adjacent to the cut off portion by the pushing of the carriage.

Abstract: A thermal image forming apparatus includes a platen roller which supports a medium, a print head, including a heating unit which applies heat to the medium to form an image thereon, which rotates around the platen roller and moves the heating unit to a first location facing a first surface of the medium and a second location facing a second surface of the medium, and a restricting element which rotates together with the print head. The restricting element restricts the movement of the platen roller in a transport direction of the medium so that the heating unit is placed at a printing nip formed by the platen roller and the print head when the print head is located at the first and second locations.

Abstract: A thermal image forming apparatus is provided. The thermal image forming apparatus includes an image forming unit including a thermal printhead and a platen that face each other and are elastically biased towards each other; a cassette including a knock-up plate on which a medium is stacked, a pickup roller that picks up the medium from the cassette, and a pickup unit that raises the knock-up plate in a direction in which the medium stacked on the knock-up plate contacts the pickup roller and lowers the knock-up plate in a direction in which the medium is separated from the pickup roller.

Abstract: A thermal image forming apparatus to form an image on a recording medium having first and second sides, the apparatus including a recording head to form the image by heating the recording medium, wherein the recording head rotates between first and second locations to respectively face the first and second sides of the recording medium; and a rotation guide to rotate along with the recording head to guide the recording medium to the recording head.

Abstract: A thermal image forming apparatus is provided. A platen roller supports a recording medium having first and second sides opposite to each other. A recording head includes a heating part that applies heat to the recording medium for image formation. The recording head rotates around the platen roller to move the heating part to first and second locations respectively facing the first and second sides of the recording medium. A conveying part conveys the recording medium. When the recording head is positioned at the first and second locations, locations of the heating part are symmetrical with each other with respect to a reference line, which passes through the conveying part and a center of the platen roller.

Abstract: A drive roller releasing apparatus for an ink-jet printer includes a drive roller separating mechanism at a drive roller to transport a printing material to a feed roller, to separate a pinch roller from the drive roller, and a controller to control the drive roller separating mechanism to separate the pinch roller from the drive roller when the printing material is moved into the feed roller. The drive roller separating mechanism includes a releasing cam to contact a pinch roller shaft. The cam surface is such that the pinch roller is gradually separated from the drive roller due to a rotation of the drive roller shaft. A one-way clutch allows the releasing cam to be rotated in one direction, and a torsion spring to bias the releasing cam to rotate in one direction in order for the cam surface thereof to be contacting with the pinch roller shaft.

Abstract: A paper transfer unit includes a pinch roller and a feed roller having a first outer portion, which defines a reference radius used to determine a paper transfer rate. A second outer portion is also provided having a substantially elastic rubber layer An elastic element elastically biases the pinch roller and the feed roller toward each other.

Abstract: An image forming apparatus is provided and includes a platen roller and a thermal printing head. The thermal printing head is elastically biased toward the platen roller and rotates about a pivot of the platen roller for moving between first and second positions to faces first and second surfaces of a medium. A transfer portion has driving and driven rollers which are rotatably engageable with each other to transfer the media. A guiding unit reduces a difference of media transfer force of the transfer portion when the thermal printing head is respectively located in the first and second positions.

Abstract: A thermal printer and a printing method are provided. The thermal printer includes a thermal printhead for applying a predetermined amount of heat to a thermal recording paper to develop a print layer provided on the thermal recording paper; a feeding roller for feeding the thermal recording paper, a platen roller for facing the thermal printhead to support the thermal recording paper, wherein the thermal recording paper passes between the thermal printhead and the platen roller, a first encoder sensor for detecting a rotation of the platen roller, a second encoder sensor for detecting rotation of the feeding roller; a counting unit for counting first and second pulse signals generated from the first and second encoder sensors, respectively, and a switching unit of the first and second pulse signals as a variable to control the feeding of the thermal recording paper.

Abstract: A complex image forming apparatus is provided having an improved structure in which a thermal printing engine forming a color image by heat and a laser printing engine performing single-color printing are integrated. The complex image forming apparatus comprises a supplying unit supplying a printing medium; a transfer path via which the printing medium supplied by the supplying unit is transferred; a thermal printing engine being disposed on the transfer path and performing color printing by heating a thermal imaging printing medium having one or more image forming layers; and a laser printing engine being disposed on the transfer path on which the thermal printing engine is installed and performing printing on the supplied printing medium by electrophotolithography.

Abstract: A method and an apparatus for forming an image on a medium having first and second surfaces wherein an image is formed on the first surface of the medium using a printing unit. After the image formation on the first surface of the medium is completed, the medium is returned to the printing start location, and a location change unit is used to move the printing unit from a first position to a second position facing a second surface of the medium, then an image is formed on the second surface of the medium using the printing unit.

Abstract: A paper feeding apparatus of an image forming device having a feeder opening and closing unit to automatically rotate a paper feeder between a storing position and a paper feeding-standby position selectively employing a driving source driving a transporting unit with a pickup roller and a feed roller. The paper feeding apparatus automatically opens the paper feeder to the paper feeding-standby position when the image forming device is used, and automatically closes the paper feeder to the storing position to minimize space when the image forming device is not in use, thereby accommodating a user and minimizing a size of the image forming device.

Abstract: A method for correcting a printing error in an inkjet printer having a printer head on which the 1st through 2Nth nozzles are provided, in which N is a positive integer greater than 0, and a feed roller, the method including: determining whether a trailing end of a print paper has escaped from the feed roller which periodically moves the print paper the width of the printer head; if the trailing end of the print paper is determined to have escaped from the feed roller, moving the print paper half the width of the printer head and printing a reference line by ejecting ink at a predetermined interval using a kth nozzle (1≦k≦N) among the 1st though Nth nozzles disposed above the print paper; moving the print paper on which the reference line is printed half the width of the printer head and printing comparison lines by ejecting ink at a predetermined interval using the (N+1)th through 2Nth nozzles disposed above the print paper; detecting an error distance between the reference line and the comparison

Abstract: A paper discharge unit for an inkjet printer which ejects a sheet on which image printing is completed by an ink cartridge out of a printer main body. The paper discharge unit for an inkjet printer includes paper discharge rollers rotatably mounted in the printer main body to feed the printing-completed sheet out of the printer main body; and paper discharge guides disposed downstream of the paper discharge rollers in a direction the sheet is fed, and guiding upward the front end portion of the sheet ejected from the paper discharge rollers to prevent the rear end portion of the sheet from being lifted. Accordingly, the front end portion of the sheet is deformed by the paper discharge guides to restrain the end portion of the sheet facing a nozzle part of the ink cartridge from being in contact with the nozzle part when the sheet is ejected, so that image printing becomes possible up to the end portion of the sheet, to thereby improve the printing efficiency of the inkjet printer.

Abstract: An image forming device has a first calculator applying any one of setting values for plural alignment patterns pre-set corresponding to magnitudes of feeding error values according to feeding amounts of a printing sheet of paper by feeding rollers and calculating first correction values for the feeding error values depending upon operation modes, a second calculator calculating second correction values for the feeding error values depending upon the printing sheet, and a controller controlling the feeding rollers to be driven to correct the feeding error values depending upon the operation modes and the printing sheet using the first and second correction values calculated by the first and second calculators. Accordingly, the image forming device can correct the feeding error values depending upon the operation modes, the printing sheet, and the printing position sections, thereby obtaining a best quality images in the respective modes.

Abstract: An image forming device has a first calculator applying any one of setting values for plural alignment patterns pre-set corresponding to magnitudes of feeding error values according to feeding amounts of a printing sheet of paper by feeding rollers and calculating first correction values for the feeding error values depending upon operation modes, a second calculator calculating second correction values for the feeding error values depending upon the printing sheet, and a controller controlling the feeding rollers to be driven to correct the feeding error values depending upon the operation modes and the printing sheet using the first and second correction values calculated by the first and second calculators. Accordingly, the image forming device can correct the feeding error values depending upon the operation modes, the printing sheet, and the printing position sections, thereby obtaining a best quality images in the respective modes.

Abstract: A drive roller releasing apparatus for an ink-jet printer includes a drive roller separating mechanism at a drive roller to transport a printing material to a feed roller, to separate a pinch roller from the drive roller, and a controller to control the drive roller separating mechanism to separate the pinch roller from the drive roller when the printing material is moved into the feed roller. The drive roller separating mechanism includes a releasing cam to contact a pinch roller shaft. The cam surface is such that the pinch roller is gradually separated from the drive roller due to a rotation of the drive roller shaft. A one-way clutch allows the releasing cam to be rotated in one direction, and a torsion spring to bias the releasing cam to rotate in one direction in order for the cam surface thereof to be contacting with the pinch roller shaft.

Abstract: A paper jamming prevention device includes a conveying portion for conveying a sheet of paper from a paper feeding portion according to a feed command; a discharging portion for receiving the conveyed sheet of paper for discharge; and a base frame, installed between the conveying portion and the discharging portion, having a flat surface disposed toward the conveying portion and a curved conveyance surface disposed toward the discharging portion, the conveyance surface deviating from the flat surface toward the discharging portion. The conveyance surface has a curved middle region and side regions which slope symmetrically upward on each side of the base frame. The discharging portion is made up of discharging rollers and star wheels installed along the curvature of the conveyance surface.

Abstract: This service station device has a wiper for cleaning a nozzle of a head, and a cap for capping and sealing for the nozzle, the wiper and the cap are provided at a moving member moved within the housing, while the head is moved to a service area from a printing area by a carriage. When the carriage is in a position for capping and sealing the nozzle by the cap, the carriage is locked at the capping and sealing position by a locking member service station device, so that the nozzle is prevented it from releasing from the capping and sealing thereof. Also, the capping and sealing of the nozzle can be maintained for a certain distance when the carriage is moved from the printing area to the service area, or from the service area to the printing area.