Abstract: An image forming apparatus comprising a fixing roller, an endless fixing belt engaged at least with the fixing roller, and a pressing roller opposite to the fixing roller with the endless fixing belt between them; wherein the image forming apparatus is equipped with a pressure changing member for changing the mean pressure on a second pressing area against which the pressing roller pressed the fixing roller via the fixing belt in the pressure area formed by the pressing roller.

Abstract: There is provided an image forming apparatus having an image forming section for forming an unfixed image on a transfer medium and a fixing device for fixing the unfixed image by sandwiching and heating the transfer medium that holds the unfixed image, wherein, the fixing device includes a fixing roller that contacts with the unfixed image, a press roller that contacts with the fixing roller, a heat belt that contacts with the fixing roller and heats the fixing roller, a plurality of support rollers for supporting the heat belt in such a manner that the heat belt is wound around the support rollers, a heat source for heating the heat belt, and a press member for pressing the heat belt against the fixing roller in a portion of the contact area where the fixing roller and the heat belt contact with each other.

Abstract: A fixing device has a heating member; a pressure applying member; an urging member for urging the pressure applying member toward the heating member; and a changeover device to increase the urging power of the urging member so that the pressure applying member is brought in pressure contact with the heating member during a pressure contact condition and to reduce the urging power of the urging member so that the pressure applying member is separated from the heating member during a pressure released condition. The urging power of the urging member under the pressure released condition is lower than that under the pressure contact condition. The changeover device comprises a stop member to limit the pressure applying member to move toward the heating member so that the pressure applying member is separated away from the heating member by the stop member during the pressure released condition.

Abstract: An embodiment of the invention includes a fixing device of an image forming apparatus. The fixing device may include a first pressure applying roller, a second pressure applying roller which is pressed onto the first pressure applying roller, and a fixing belt which is entrained about the first pressure applying roller and is pressed onto the first pressure applying roller by the second pressure applying roller. When a transfer material carrying an unfixed image is inserted between the second pressure applying roller and the fixing belt, the unfixed image may be brought into contact with the fixing belt so that the unfixed image is heated and fixed on the transfer material. A frictional coefficient between the fixing belt and the first pressure applying roller may be set to be less than a frictional coefficient between the fixing belt and the transfer material.

Abstract: This invention relates to an image forming apparatus having a fixing device which pressurizes and heats an unfixed toner image on a paper sheet as the transfer medium to fix the image on the paper sheet as the transfer medium. This image forming apparatus includes a glossiness changing device and/or a fixing condition changing device which changes fixing conditions in accordance with the thickness or thickness information of a paper sheet as the transfer medium, and a control section for changing the output order of fixed images to be printed out. This makes it possible to rearrange a printing order so as to shorten the time required to switch a glossiness or change a fixing condition, thereby greatly improving printing efficiency.

Abstract: There is provided an image forming apparatus having an image forming section for forming an unfixed image on a transfer medium and a fixing device for fixing the unfixed image by sandwiching and heating the transfer medium that holds the unfixed image, wherein, the fixing device includes a fixing roller that contacts with the unfixed image, a press roller that contacts with the fixing roller, a heat belt that contacts with the fixing roller and heats the fixing roller, a plurality of support rollers for supporting the heat belt in such a manner that the heat belt is wound around the support rollers, a heat source for heating the heat belt, and a press member for pressing the heat belt against the fixing roller in a portion of the contact area where the fixing roller and the heat belt contact with each other.

Abstract: An image forming apparatus comprising a fixing roller, an endless fixing belt engaged at least with the fixing roller, and a pressing roller opposite to the fixing roller with the endless fixing belt between them; wherein the image forming apparatus is equipped with a pressure changing member for changing the mean pressure on a second pressing area against which the pressing roller pressed the fixing roller via the fixing belt in the pressure area formed by the pressing roller.

Abstract: An image forming apparatus containing a fixing device for fixing on sheet a toner image formed on the sheet by applying heat and pressure. This fixing device includes a belt having an elastic layer for applying heat and pressure to the sheet, and a first pressure roller and a second pressure roller, located opposite to each other with the paper interposed in between, for applying pressure to the belt and sheet. The first pressure roller, having no elastic layer on the outer periphery, is arranged inside the belt, and support points of a support member for supporting the first pressure roller is located within a width of the sheet passing through.

Abstract: In a method of controlling a fixing device having a heating roller containing a heat source, at least one supporting roller spaced from the heating roller, a fixing belt trained about the heating roller and the supporting roller, and a pressing roller placed to form a nipping area between the fixing belt and the pressing roller, giving a pressing force to the heating roller or the supporting roller through the fixing belt, the method includes the steps of: presetting a desired glossiness of fixed images; detecting a temperature of the pressing roller; calculating a target heating roller temperature from the preset glossiness of fixed images, the detected temperature of the pressing roller, a calculated loaded nipping time, a false nipping time, and a loaded nipping surface pressure; and controlling an operating status of the heat source according to the calculated target heating roller temperature.

Abstract: A fixing device of an image forming apparatus, including:

Abstract: The fixing device having therein the heating member for heating a toner image, the pressure applying member arranged to face the heating member for performing a pressure contact to the heating member, an urging means which urges the pressure applying means, and a changeover means which changes the condition of the pressure applying member from the pressure contact condition to the heating member to the pressure contact released condition by controlling the urging means, wherein urging power by the urging means under the pressure contact released condition is lower than that under the pressure contact condition.

Abstract: A fixing device has a heating member; a pressure applying member; an urging member for urging the pressure applying member toward the heating member; and a changeover device to increase the urging power of the urging member so that the pressure applying member is brought in pressure contact with the heating member during a pressure contact condition and to reduce the urging power of the urging member so that the pressure applying member is separated from the heating member during a pressure released condition. The urging power of the urging member under the pressure released condition is lower than that under the pressure contact condition. The changeover device comprises a stop member to limit the pressure applying member to move toward the heating member so that the pressure applying member is separated away from the heating member by the stop member during the pressure released condition.

Abstract: This invention relates to an image forming apparatus having a fixing device which pressurizes and heats an unfixed toner image on a paper sheet as the transfer medium to fix the image on the paper sheet as the transfer medium. This image forming apparatus includes a glossiness changing device and/or a fixing condition changing device which changes fixing conditions in accordance with the thickness or thickness information of a paper sheet as the transfer medium, and a control section for changing the output order of fixed images to be printed out. This makes it possible to rearrange a printing order so as to shorten the time required to switch a glossiness or change a fixing condition, thereby greatly improving printing efficiency.

Abstract: The invention concerns the image forming apparatus incorporating a fixing unit, which is includes either a fixing belt or a fixing roller, and effectively used in a copier or a printer. The fixing unit includes a fixing belt threaded on a plurality of supporting rollers and a temperature-equalizing member to equalize a temperature distribution of the fixing belt in its width direction. The temperature-equalizing member moves from a separate position to a first pressure-contacting position at which the temperature-equalizing member pressure-contacts the fixing belt, and further moves to a second pressure-contacting position while maintaining a pressure-contacting state with the fixing belt. A contact area of the temperature-equalizing member and the fixing belt is enlarged at the second pressure-contacting position, compared to that at the first pressure-contacting position. The temperature-equalizing member can park at either the first pressure-contacting position or the second pressure-contacting position.

Abstract: An image fixing apparatus in which a fixing belt is trained about a plurality of support rollers including therein one support roller housing a heat applying source, and a relative position of a pair of pressure rollers is changed, which are oppositely arranged with the fixing belt interposed between them, to a pressure position, a traveling path of the fixing belt is changed, and through the fixing belt whose path is changed, the heat applying source and the support roller housing the heat applying source are integrally movable.

Abstract: In a method of controlling a fixing device having a heating roller containing a heat source, at least one supporting roller spaced from the heating roller, a fixing belt trained about the heating roller and the supporting roller, and a pressing roller placed to form a nipping area between the fixing belt and the pressing roller, giving a pressing force to the heating roller or the supporting roller through the fixing belt, the method includes the steps of: presetting a desired glossiness of fixed images; detecting a temperature of the pressing roller; calculating a target heating roller temperature from the preset glossiness of fixed images, the detected temperature of the pressing roller, a calculated loaded nipping time, a false nipping time, and a loaded nipping surface pressure; and controlling an operating status of the heat source according to the calculated target heating roller temperature.

Abstract: The fixing device having therein the heating member for heating a toner image, the pressure applying member arranged to face the heating member for performing a pressure contact to the heating member, an urging means which urges the pressure applying means, and a changeover means which changes the condition of the pressure applying member from the pressure contact condition to the heating member to the pressure contact released condition by controlling the urging means, wherein urging power by the urging means under the pressure contact released condition is lower than that under the pressure contact condition.

Abstract: An image fixing apparatus in which a fixing belt is trained about a plurality of support rollers including therein one support roller housing a heat applying source, and a relative position of a pair of pressure rollers is changed, which are oppositely arranged with the fixing belt interposed between them, to a pressure position, a traveling path of the fixing belt is changed, and through the fixing belt whose path is changed, the heat applying source and the support roller housing the heat applying source are integrally movable.

Abstract: The invention concerns the image forming apparatus incorporating a fixing unit, which is includes either a fixing belt or a fixing roller, and effectively used in a copier or a printer. The fixing unit includes a fixing belt threaded on a plurality of supporting rollers and a temperature-equalizing member to equalize a temperature distribution of the fixing belt in its width direction. The temperature-equalizing member moves from a separate position to a first pressure-contacting position at which the temperature-equalizing member pressure-contacts the fixing belt, and further moves to a second pressure-contacting position while maintaining a pressure-contacting state with the fixing belt. A contact area of the temperature-equalizing member and the fixing belt is enlarged at the second pressure-contacting position, compared to that at the first pressure-contacting position. The temperature-equalizing member can park at either the first pressure-contacting position or the second pressure-contacting position.

Abstract: There is described a method for manufacturing fixing rollers and a roller body holding device utilized for manufacturing fixing rollers. The method includes steps of press-fitting flanges into a roller body, shaped in a hollow cylinder, from each of both end openings of the roller body with putting an elastic material between each of the flanges and the roller body; installing the roller body in a shaping mold so that the roller body is supported by the flanges and the elastic material at a predetermined position in the shaping mold; injecting a melted rubber into a space between the roller body and the shaping mold from an injection opening; and curing the melted rubber injected into the space. The roller body holding device for holding a roller body is shaped in a hollow cylinder and includes a flange, which is press-fitted into the roller body from each of end openings of the roller body; and an elastic material disposed between the flange and the roller body.