Abstract: An image forming apparatus and a method of controlling the same is provided. A plurality of cells formed at the surface of a transfer roller is filled with a developing agent to initialize the transfer roller, thereby suppressing contamination and electrical non-uniformity of the transfer roller. A method of controlling an image forming apparatus includes determining whether a transfer roller mounted in the image forming apparatus is a new one and, upon determining that the transfer roller is a new one, feeding a developing agent to the surface of the transfer roller and filling a plurality of cells formed at the surface of the transfer roller with the developing agent to initialize the transfer roller.

Abstract: An image forming apparatus and method are provided. The image forming apparatus includes a communication interface unit that receives printing data, an image forming unit that performs an ordinary printing to form an image on printing paper based on the printing data, a paper supplying unit that provides the printing paper to the image forming unit along with a paper supplying route, a determination unit that determines whether a functional printing may be performed on the paper supplying route in an interval section between sheets of the printing paper, and a controller that controls the image forming unit to perform a functional printing, wherein the ordinary printing is a printing performed on one or more sheets of printing paper, and the functional printing is a printing performed in an interval section between the sheets of printing paper.

Abstract: An image forming apparatus and a method of controlling the same is provided. A plurality of cells formed at the surface of a transfer roller is filled with a developing agent to initialize the transfer roller, thereby suppressing contamination and electrical non-uniformity of the transfer roller. A method of controlling an image forming apparatus includes determining whether a transfer roller mounted in the image forming apparatus is a new one and, upon determining that the transfer roller is a new one, feeding a developing agent to the surface of the transfer roller and filling a plurality of cells formed at the surface of the transfer roller with the developing agent to initialize the transfer roller.

Abstract: An image forming apparatus which includes a fan to generate an air flow within the image forming apparatus, and a controller to drive the fan at a first speed corresponding to a first time period representing an image forming operation and to drive the fan at a second speed corresponding to a second time period corresponding to operations other than the image forming operation.

Abstract: A structure to guide a take-in direction of a print medium to be taken in a carrying part where the print medium is carried, the structure includes: a guide unit which changes a travel direction of the print medium from a feeding direction, in which the print medium is supplied from a medium feeding unit, to the take-in direction of the print medium; and a vibration damper which prevents a bottom part of the print medium from shaking and vibrating when the print medium is free from the guide unit.

Abstract: An image forming apparatus and a control method in which a power source having the same polarity as that of a transfer power source can be applied to a drive roller at a time at which an upper end of the recording medium is detached from the ITB, such that repulsive force against the recording medium can occur, and the detachment of the recording medium can be more easily carried out. Another power source having the opposite polarity to the transfer power source can be applied to the drive roller at another time at which the adhesive force between the back end of the recording medium and the ITB becomes weaker, such that attractive force drawing the recording medium to the ITB can occur and the recording medium can be brought into contact with the ITB with higher force.

Abstract: An image forming apparatus and method are provided. The image forming apparatus includes a communication interface unit that receives printing data, an image forming unit that performs an ordinary printing to form an image on printing paper based on the printing data, a paper supplying unit that provides the printing paper to the image forming unit along with a paper supplying route, a determination unit that determines whether a functional printing may be performed on the paper supplying route in an interval section between sheets of the printing paper, and a controller that controls the image forming unit to perform a functional printing, wherein the ordinary printing is a printing performed on one or more sheets of printing paper, and the functional printing is a printing performed in an interval section between the sheets of printing paper.

Abstract: An image forming apparatus may include: a plurality of image bearing members; an exposure unit; a developing unit; a transfer unit including a plurality of transfer rollers and a plurality of erasers each disposed between the transfer rollers; and a fixing unit. The eraser may be disposed in a zone Z1 satisfying the following formula: D1?Z1?D?D3; D1=4.5 mm; D3=4.5 mm; and 9.0 mm<D Here, D1 may be an allowable minimum distance between an end part of the eraser and a center of a first transfer nip between a first image bearing member and a first transfer roller; D3 may be an allowable minimum distance between the end part of the eraser and a center of a second transfer nip between a second image bearing member and a second transfer roller; and D may be a distance between the centers of the transfer nips.

Abstract: An image forming apparatus and a control method thereof to improve quality of an image in consideration of a change in posture of a print media. The image forming apparatus can include a transferred unit on which a visible image is formed, a transferring unit to form a transfer region through which the visible image is transferred onto a print medium, along with the transferred unit, a bias supplying unit to supply bias to the transferring unit so that a transfer electric field is produced in the transfer region, and a controller to control the bias supplying unit to supply different first to third biases to the transferring unit while at least first to third regions of the print medium pass through the transfer region, respectively.

Abstract: An image forming apparatus and a control method thereof to improve quality of an image in consideration of a change in posture of a print media. The image forming apparatus can include a transferred unit on which a visible image is formed, a transferring unit to form a transfer region through which the visible image is transferred onto a print medium, along with the transferred unit, a bias supplying unit to supply bias to the transferring unit so that a transfer electric field is produced in the transfer region, and a controller to control the bias supplying unit to supply different first to third biases to the transferring unit while at least first to third regions of the print medium pass through the transfer region, respectively.

Abstract: An image forming apparatus and a control method thereof to improve quality of an image in consideration of a change in posture of a print media. The image forming apparatus can include a transferred unit on which a visible image is formed, a transferring unit to form a transfer region through which the visible image is transferred onto a print medium, along with the transferred unit, a bias supplying unit to supply bias to the transferring unit so that a transfer electric field is produced in the transfer region, and a controller to control the bias supplying unit to supply different first to third biases to the transferring unit while at least first to third regions of the print medium pass through the transfer region, respectively.

Abstract: An image forming apparatus includes a photoconductive medium electrified by an electrifying apparatus to a predetermined electric potential, a plurality of color developing apparatuses which are fixed around the photoconductive medium, each color developing apparatus having a developing roller to adhere a predetermined color toner to an electrostatic latent image formed on the photoconductive medium by a laser scanning unit, and a supplying roller to supply a toner to the developing roller, a voltage supplying apparatus to apply a predetermined bias voltage to the developing roller and the supplying roller, and a controlling apparatus to control a degree and a timing of applying the bias voltages to the developing roller and the supplying roller to control a movement state of the toner between the supplying roller and the developing roller.

Abstract: A transfer voltage control method of an image forming apparatus includes supplying a first measurement voltage to a first transfer member and a second transfer member, measuring a variation in resistance of the first transfer member by supplying a second measurement voltage to the first transfer member during a first period of time, and measuring a variation in resistance of the second transfer member by supplying the second measurement voltage during a second period of time. Therefore, it is capable of measuring accurately a variation in resistance of a transfer unit, such that an optimum transfer voltage may be set. Accordingly, transfer quality of an image forming apparatus is improved.

Abstract: An image forming apparatus which includes a fan to generate an air flow within the image forming apparatus, and a controller to drive the fan at a first speed corresponding to a first time period representing an image forming operation and to drive the fan at a second speed corresponding to a second time period corresponding to operations other than the image forming operation.

Abstract: An image forming apparatus includes at least one supporting roller, a movable belt supported by the supporting roller, and a shifting restricting unit to prevent the movable belt from shifting to any one side along an axial direction of the supporting roller. The shifting restricting unit includes a guide rail formed between the movable belt and the supporting roller to guide movement of one end of the movable belt, and a belt pressurizing member formed at the other end of the movable belt to generate tension on the movable belt to compensate for a shifting force on the guide rail side by the guide rail.

Abstract: An image forming apparatus capable of varying a transferring force according to an amount of developer, thereby improving transfer quality, and a control method thereof. The image forming apparatus includes a plurality of photoconductive media on which electrostatic latent images are formed, a transfer unit onto which color developer images respectively developed on the plurality of photoconductive media are transferred and superimposed in sequence, and a controller to control in a manner that electric potential differences between image areas and non-image areas of the electrostatic latent images vary in an order in which the color developer images are transferred.

Abstract: An image forming apparatus and a control method thereof wherein a power source having the same polarity as that of a transfer power source can be applied to a drive roller at a time at which an upper end of the recording medium is detached from the ITB, such that repulsive force against the recording medium can occur, and the detachment of the recording medium can be more easily carried out. Another power source having the opposite polarity to the transfer power source can be applied to the drive roller at another time at which the adhesive force between the back end of the recording medium and the ITB becomes weaker, such that attractive force drawing the recording medium to the ITB can occur and the recording medium can be brought into contact with the ITB with higher force.

Abstract: An image transfer device to accurately measure a resistance of a printing medium or a transfer belt, an image forming apparatus having the image transfer device, and a method of measuring the resistance of the printing medium. The image transfer device includes a conveyance unit, to which a reference voltage or current is applied, and which includes a first roller having variations of resistance along a circumferential direction, and a second roller to support the first roller, a transfer roller spaced apart from the first roller by a distance corresponding to at least the circumference of the first roller to transfer a developer agent of a photosensitive drum onto a printing medium, and a controller to measure resistance of the printing medium by detecting electric current or voltage difference between the first and the second rollers, and to supply the transfer roller with a transfer voltage or a current according to the detected resistance of the printing medium.

Abstract: The image forming apparatus may include: a plurality of image bearing members; an exposure unit; a developing unit; a transfer unit including a plurality of transfer rollers and a plurality of erasers each disposed between the transfer rollers; and a fixing unit. The eraser may be disposed in a zone Z1 satisfying the following formula: D1?Z1?D?D3; D1=4.5 mm; D3=4.5 mm; and 9.

Abstract: A structure to guide a take-in direction of a print medium to be taken in a carrying part where the print medium is carried, the structure includes: a guide unit which changes a travel direction of the print medium from a feeding direction, in which the print medium is supplied from a medium feeding unit, to the take-in direction of the print medium; and a vibration damper which prevents a bottom part of the print medium from shaking and vibrating when the print medium is free from the guide unit.