Abstract: An example image forming apparatus includes a main body, a printing engine to be disposed in the main body to form an image on a printing medium, a fixing apparatus including a fixing roller and a fixing belt disposed to face the fixing roller, and a jam prevention apparatus including a fixed frame disposed adjacent to the fixing apparatus, and a movable apparatus to be detachably fastened to the fixed frame through a plurality of adjusting screws, to adjust a gap with the fixing belt according to a fastening direction of the plurality of adjusting screws.

Abstract: An example image forming apparatus includes a main body, a printing engine to be disposed in the main body to form an image on a printing medium, a fixing apparatus including a fixing roller and a fixing belt disposed to face the fixing roller, and a jam prevention apparatus including a fixed frame disposed adjacent to the fixing apparatus, and a movable apparatus to be detachably fastened to the fixed frame through a plurality of adjusting screws, to adjust a gap with the fixing belt according to a fastening direction of the plurality of adjusting screws.

Abstract: Disclosed herein are an image fixing device and an image forming apparatus having the same. The image fixing device includes a fixing belt which is rotatably disposed, and a pressure roller which is disposed to be opposite to the fixing belt and thus to press an outer circumferential surface of the fixing belt, wherein the fixing belt includes a fixing part of which an outer surface has a first friction coefficient, and a meandering movement preventing part which is located at each of both ends of the fixing part in a length direction of the fixing belt, and of which an outer surface has a second friction coefficient greater than the first friction coefficient. By the configuration, a meandering movement of the fixing belt is prevented, and thus it is possible to improve fixing efficiency.

Abstract: An image fixing apparatus includes a heat roller, and plural pressure rollers, which rotationally contact the surface of the heat roller by a compression unit. The plural pressure rollers are provided in such a manner that the compressive forces thereof may be adjusted. With this construction, the fixability of a toner image is improved and crumples, wrinkles, and wrap jam that may be produced when a toner image is fixed are substantially prevented.

Abstract: A fusing device to fuse an image to a printing medium, the fusing device including: a heating roller; a first pressing roller, which presses the printing medium against the heating roller; and a second pressing roller which attached to the first pressing roller, to detach the printing medium from the first pressing roller. The first and second pressing rollers are biased against the heating roller such that the first and second pressing rollers move according to a change in a position of the heating roller.

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: A fixing unit, an electro-photographic image forming apparatus having the same, and a printing method thereof are provided. The electro-photographic image forming apparatus includes a printing unit that forms a toner image on a recording medium by an electro-photographic method, a heat roller, a first pressure roller that faces the heat roller and forms a first fixing nip therebetween, one or more second pressure rollers that face the heat roller and form a second fixing nip therebetween, and a guide member that changes its position to a first position for guiding the recoding medium to the second fixing nip after the recording medium passes through the first fixing nip or to a second position for blocking the recording medium from moving to the second fixing nip after the recording medium passes through the first fixing nip.

Abstract: A fixing unit fixing an image on a paper and an image-forming apparatus having the same are provided. The fixing unit includes a heat roller, pressure rollers, a bracket, springs, and a paper guide. The heat roller has a heat source therein and the pressure rollers face the heat roller to form fixing nips. The bracket rotatably supports the pressure rollers and is also adapted to pivot. The springs elastically pressurize the bracket to closely attach the pressure rollers on the heat roller and the paper guide guides a paper so that a paper jam may not occur between the pressure rollers.

Abstract: A fusing device to fuse an image to a printing medium, the fusing device including: a heating roller; a first pressing roller, which presses the printing medium against the heating roller; and a second pressing roller which attached to the first pressing roller, to detach the printing medium from the first pressing roller. The first and second pressing rollers are biased against the heating roller such that the first and second pressing rollers move according to a change in a position of the heating roller.

Abstract: A fusing device of an electrophotographic image forming apparatus. The fusing device includes a fusing roller that is heated to be a predetermined temperature, and a pressing roller that presses a sheet of paper passing between the fusing roller and the pressing roller toward the fusing roller. In addition, the fusing roller includes a cylindrical roller having a predetermined diameter, a heater positioned inside the cylindrical roller to heat the cylindrical roller, a rubber member that is formed on a center portion of an outer circumference on the cylindrical roller, and heat resistance portion that is formed on both end portions of the cylindrical roller.

Abstract: A fusing unit of an image forming apparatus is capable of controlling fusing pressure according to detailed types of printing medium without deteriorating printing speed. A first roller rotates about a first rotation shaft CR1. A second roller rotates in contact with the first roller about a second rotation shaft CR2 and is movable along the outer circumference of the first roller. A moving unit relocates the second roller according to a type of printing medium. A pressing unit presses the second roller toward the first roller by applying different pressures according to a position of the second roller with respect to the first roller.

Abstract: A fixing unit, an electro-photographic image forming apparatus having the same, and a printing method thereof are provided. The electro-photographic image forming apparatus includes a printing unit that forms a toner image on a recording medium by an electro-photographic method, a heat roller, a first pressure roller that faces the heat roller and forms a first fixing nip therebetween, one or more second pressure rollers that face the heat roller and form a second fixing nip therebetween, and a guide member that changes its position to a first position for guiding the recoding medium to the second fixing nip after the recording medium passes through the first fixing nip or to a second position for blocking the recording medium from moving to the second fixing nip after the recording medium passes through the first fixing nip.

Abstract: An image fixing apparatus includes a heat roller, and plural pressure rollers, which rotationally contact the surface of the heat roller by a compression unit. The plural pressure rollers are provided in such a manner that the compressive forces thereof may be adjusted. With this construction, the fixability of a toner image is improved and crumples, wrinkles, and wrap jam that may be produced when a toner image is fixed are substantially prevented.

Abstract: An image forming apparatus includes a shielding member protruding from a top surface of an upper frame and forming a chamber portion having a predetermined area together with an upper cover of the main body covering the shielding member so as to include a plurality of heat dissipating holes perforated in the upper frame at predetermined intervals along a lengthwise direction, and a pump installed at one side of the chamber portion and blowing air into the chamber portion to form a laminar flow to prevent heat generated by a fusing roller from heating an upper cover of the image forming apparatus.

Abstract: A fixing unit fixing an image on a paper and an image-forming apparatus having the same are provided. The fixing unit includes a heat roller, pressure rollers, a bracket, springs, and a paper guide. The heat roller has a heat source therein and the pressure rollers face the heat roller to form fixing nips. The bracket rotatably supports the pressure rollers and is also adapted to pivot. The springs elastically pressurize the bracket to closely attach the pressure rollers on the heat roller and the paper guide guides a paper so that a paper jam may not occur between the pressure rollers.

Abstract: A fusing unit of an image forming apparatus is capable of controlling fusing pressure according to detailed types of printing medium without deteriorating printing speed. A first roller rotates about a first rotation shaft CR1. A second roller rotates in contact with the first roller about a second rotation shaft CR2 and is movable along the outer circumference of the first roller. A moving unit relocates the second roller according to a type of printing medium. A pressing unit presses the second roller toward the first roller by applying different pressures according to a position of the second roller with respect to the first roller.

Abstract: A paper detecting device includes a paper contact arm, one side of which contacts a surface of a sheet of paper and the other side is connected to a rotating member. A sensor unit senses the rotation of the paper contact arm. An elastic member elastically biases the paper contact arm in the direction in which the paper contact arm contacts the sheet of paper. A contact force regulating unit is installed to generate a rotational force in the direction opposite to the direction of an elastic force by the elastic member. Accordingly, because the paper contact arm is returned to its initial position by the elastic member, paper jams are substantially prevented. The contact force regulating unit regulates the paper contact force within a predetermined range to avoid damage and contamination of a sheet of paper. The simple structure of the paper detecting device improves mass-production thereof.

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: A fusing device of an electrophotographic image forming apparatus. The fusing device includes a fusing roller that is heated to be a predetermined temperature, and a pressing roller that presses a sheet of paper passing between the fusing roller and the pressing roller toward the fusing roller. In addition, the fusing roller includes a cylindrical roller having a predetermined diameter, a heater positioned inside the cylindrical roller to heat the cylindrical roller, a rubber member that is formed on a center portion of an outer circumference on the cylindrical roller, and heat resistance portion that is formed on both end portions of the cylindrical roller.

Abstract: Provided is an image forming apparatus, which comprises a shielding member protruding from a top surface of the upper frame and forming a chamber portion having a predetermined area together with the upper cover of the main body covering the shielding member so as to include a plurality of heat dissipating holes perforated in the upper frame at predetermined intervals along a lengthwise direction, and a pump installed at one side of the chamber portion and blowing air into the chamber portion to form a laminar flow to prevent heat generated by a fusing roller from heating an upper cover of the image forming apparatus.