Abstract: An image forming apparatus including a printing unit which prints an image on paper, an exit path which connects an exit of the printing unit to an exit member which pushes the paper outside of the printing unit, a plurality of guide members which are arranged widthwise of the paper, each guide member having a first guide side which guides the paper coming out of the printing unit along the exit path, wherein each guide member is installed to be movable such that the first guide side rotates when the first guide side contacts the paper which comes out of the printing unit, and returns to its original position after the paper completely passes through the printing unit.

Abstract: A fusing unit provided in a printing path of an image forming apparatus to fuse an image transferred onto a printable medium, the fusing unit including a heat source; a heating roller of which a surface is heated by heat generated by the heat source; a plurality of pressing rollers which is provided opposite to the heating roller and presses a supplied printable medium in cooperation with the heating roller; a fusing pressing belt which is wound on the plurality of pressing rollers and forms a fusing nip contacting with the heating roller; and a supporting unit which rotatably supports the plurality of pressing rollers and guides the fusing pressing belt, a surface hardness hP of at least one of the plurality of pressing rollers is greater than or equal to a surface hardness hH of the heating roller.

Abstract: A fusing device that is provided on a printing passage of an image forming apparatus and fuses an image transferred to a print medium, the fusing device including: a heating roller; a pressure roller to press the print medium fed along the printing passage against the heating roller; a separation roller to separate the print medium from the heating roller; a fusing pressure belt that winds around the pressure roller and the separation roller; a first elastic member to pressure the pressure roller towards the heating roller along a first line; and a second elastic member to pressure the separation roller towards the heating roller, wherein the first line passes through a center of the pressure roller and forms an angle towards the separation roller with a second line that passes through a center of the heating roller and the center of the pressure roller.

Abstract: An image forming apparatus includes a developing unit to form an image using a developing agent on one side of a printing medium transported along a simplex printing path, a fixing unit to fix the developing agent on the printing medium, a discharging roller to discharge the printing medium that passes the fixing unit, and a first driving source to drive the developing unit, the fixing unit and the discharging roller.

Abstract: A method and apparatus for fuser cooling fan control is provided. An image forming apparatus so configured comprises a fixing unit, a cooling fan for cooling the fixing unit, a detecting sensor for measuring ambient temperature and humidity of the image forming apparatus, and a controller for recognizing ambient temperature and humidity change from the measurement provided by the detecting sensor. The controller controls operation of the cooling fan according to the temperature and humidity change detected. The controller delays operation of the cooling fan by an amount of time if the ambient temperature and/or humidity is below a reference temperature and humidity level.

Abstract: A bearing structure reduces friction between a roller and a bearing under a pressure. A fusing device for an image forming apparatus employs the bearing structure. The bearing structure installed between a frame and a rotary shaft supports the rotary shaft on the frame. A bearing body has a fitting part in which the rotary shaft is rotatably fitted. A rolling support unit is installed on at least one portion inside the fitting part to contact the rotary shaft in a rolling manner. The fusing device includes a fusing roller in which a heater is embedded, and a pressure roller that faces the fusing roller and cooperates with the fusing roller in pressing a sheet of paper passing therebetween. Bearing structures rotatably support the fusing roller and the pressure roller on a frame. Each bearing structure includes a bearing body having a fitting part, and a rolling support unit installed on at least one area inside the fitting part to contact the fitted roller in a rolling manner.

Abstract: An image forming apparatus including a printing unit which prints an image on paper, an exit path which connects an exit of the printing unit to an exit member which pushes the paper outside of the printing unit, a plurality of guide members which are arranged widthwise of the paper, each guide member having a first guide side which guides the paper coming out of the printing unit along the exit path, wherein each guide member is installed to be movable such that the first guide side rotates when the first guide side contacts the paper which comes out of the printing unit, and returns to its original position after the paper completely passes through the printing unit.

Abstract: An image forming apparatus including a printing unit which prints an image on paper, an exit path which connects an exit of the printing unit to an exit member which pushes the paper outside of the printing unit, a plurality of guide members which are arranged widthwise of the paper, each guide member having a first guide side which guides the paper coming out of the printing unit along the exit path, wherein each guide member is installed to be movable such that the first guide side rotates when the first guide side contacts the paper which comes out of the printing unit, and returns to its original position after the paper completely passes through the printing unit.

Abstract: A fuser of an electrophotographic image forming apparatus fuses a toner image to a recording medium by applying heat and pressure. The fuser includes first and second rollers that are elastically biased against each other and that rotate while facing each other. An elastic layer is provided on at least one of the first and second rollers, and a heat source is provided on at least one of the first and second rollers. A gear is coupled to an end portion of at least one of the first and second rollers. First and second interval maintenance members are respectively coupled to the first and second rollers at the end portions of the rollers which are opposite to the end portion where the gear is coupled. The first and second maintenance members face each other and contact each other to regulate an amount of compression of the elastic layer.

Abstract: A fusing unit and a fusing apparatus using the fusing unit are provided. The fusing unit includes a pipe-shaped fusing roller having a heat generating unit and electrode members at both ends thereof. A power supply unit contacts the electrode members and supplies current thereto. A blocking member is disposed between the electrode members and the power supply units to block current by separating the power supply unit from the electrode members when a temperature of the heat generating unit rapidly increases.

Abstract: A fusing device that is provided on a printing passage of an image forming apparatus and fuses an image transferred to a print medium, the fusing device including: a heating roller; a pressure roller to press a print medium fed along the printing passage against the heating roller; a separation roller to separate the print medium from the heating roller; a fusing pressure belt that winds around the pressure roller and the separation roller; a first elastic member to pressure the pressure roller towards the heating roller along a first line; and a second elastic member to pressure the separation roller towards the heating roller, wherein the first line passes through a center of the pressure roller and forms an angle towards the separation roller with a second line that passes through a center of the heating roller and the center of the pressure roller.

Abstract: An image forming apparatus includes a developing unit to form an image using a developing agent on one side of a printing medium transported along a simplex printing path, a fixing unit to fix the developing agent on the printing medium, a discharging roller to discharge the printing medium that passes the fixing unit, and a first driving source to drive the developing unit, the fixing unit and the discharging roller.

Abstract: A fusing unit provided in a printing path of an image forming apparatus to fuse an image transferred onto a printable medium, the fusing unit including a heat source; a heating roller of which a surface is heated by heat generated by the heat source; a plurality of pressing rollers which is provided opposite to the heating roller and presses a supplied printable medium in cooperation with the heating roller; a fusing pressing belt which is wound on the plurality of pressing rollers and forms a fusing nip contacting with the heating roller; and a supporting unit which rotatably supports the plurality of pressing rollers and guides the fusing pressing belt, a surface hardness hP of at least one of the plurality of pressing rollers is greater than or equal to a surface hardness hH of the heating roller.

Abstract: A roller assembly for an image forming apparatus includes a roller, a bearing for rotatably supporting the roller, a roller cover to be assembled at both ends of the roller, a bushing to be introduced between the roller and the bearing, and a support unit disposed at the roller and the bushing to suppress sliding movement between the roller and the bushing and shaking of the roller in an axial direction.

Abstract: A fusing unit of an image forming apparatus and method for preventing defective fusing of an image are provided, in which a heating roller includes a heat source and is rotatably installed on a frame, a pressing roller presses a sheet of paper toward the heating roller to fuse a toner image on the paper, a pressing unit elastically bias the pressing roller to the heating roller, and a pressure sensor measures a pressure of the pressing roller. Accordingly, defective fusing of a toner image onto the paper and overheating of the fusing unit can be prevented.

Abstract: A fixing device and image forming apparatus, and a method thereof are provided. The fixing device and image forming apparatus include a heat roller heated by a heat source; a pressure roller disposed opposite to the heat roller; a temperature cutoff device spaced apart from the heat roller to cut the power supply of the heat source when the temperature of the heat roller is higher than a predetermined temperature; and a contact member that causes the heat roller and the temperature cutoff device to come in contact with each other so that the heat of the heat roller is transmitted to the temperature cutoff device.

Abstract: An apparatus to switch a paper feed direction for an image forming device includes a paper guide part disposed across a paper feed path to move from an initial position to a paper passing position or a paper jam removing position by a force generated by passing of the paper, or external power; a supporting part to rotatably fix the paper guide part to a frame of the office machine; an elastic restoring part to restore the paper guide part from the paper jam removing position to the paper passing position; and a restoring force blocking part to block a force of the elastic restoring part from acting on the paper guide part until the paper guide part fixed to the supporting part rotates beyond the paper passing position.

Abstract: A fusing unit and a fusing apparatus using the fusing unit are provided. The fusing unit includes a pipe-shaped fusing roller having a heat generating unit and electrode members at both ends thereof. A power supply unit contacts the electrode members and supplies current thereto. A blocking member is disposed between the electrode members and the power supply units to block current by separating the power supply unit from the electrode members when a temperature of the heat generating unit rapidly increases.

Abstract: A roller assembly for an image forming apparatus includes a roller, a bearing for rotatably supporting the roller, a roller cover to be assembled at both ends of the roller, a bushing to be introduced between the roller and the bearing, and a support unit disposed at the roller and the bushing to suppress sliding movement between the roller and the bushing and shaking of the roller in an axial direction.

Abstract: A method and apparatus for fuser cooling fan control is provided. An image forming apparatus so configured comprises a fixing unit, a cooling fan for cooling the fixing unit, a detecting sensor for measuring ambient temperature and humidity of the image forming apparatus, and a controller for recognizing ambient temperature and humidity change from the measurement provided by the detecting sensor. The controller controls operation of the cooling fan according to the temperature and humidity change detected. The controller delays operation of the cooling fan by an amount of time if the ambient temperature and/or humidity is below a reference temperature and humidity level.