Abstract: A fixing apparatus includes a first pressing roller, a belt wound around the first pressing roller, a second pressing roller, and a roller position changer that changes a position of the second pressing roller. The second pressing roller faces the first pressing roller across the belt and forms a fixing nip portion between itself and the belt. At least one of the first pressing roller and the second pressing roller includes a core metal and a foam body covering the core metal. The roller position changer changes a position of the second pressing roller based on a kind of print medium to change a peak surface pressure of the fixing nip portion, such that a range where maximum shearing strain occurs from an interface between the core metal and the foam body in the foam body is a predetermined range.

Abstract: An image forming apparatus includes: an image former that forms a toner image on a recording material; a fixing device that pressurizes and heats the toner image formed on the recording material by the image former to be fixed on the recording material; and a hardware processor that estimates a remaining life of a predetermined fixing member on the basis of a temperature history in a temperature control period including a non-sheet passage time of the fixing member that forms a fixing nip in the fixing device and is raised in temperature and rotated.

Abstract: A fixing apparatus, includes a first pressing roller, a belt wound around the first pressing roller, a second pressing roller disposed to face the first pressing roller across the belt and to form a fixing nip portion between itself and the belt, and a roller position changer that changes a position of the second pressing roller, wherein at least one of the first pressing roller and the second pressing roller is a roller including a core metal and a foaming body covering the core metal, and the roller position changer changes a position of the second pressing roller to be able to change a peak surface pressure of the fixing nip portion correspondingly to a kind of a print medium so that a range where maximum shearing strain occurs from an interface between the core metal and the foaming body in the foaming body becomes a predetermined range.

Abstract: An image forming apparatus has an image forming unit that forms an image on a sheet, a fixing unit that performs fixing of the sheet on which the image is formed, a first conveyance route that has a reverse conveyance route and a second conveyance route that does not pass the reverse conveyance route, and a control unit that performs first control for conveying a previously printed sheet which is printed previously via the first conveyance route and second control for conveying a subsequently printed sheet which is printed subsequently via the second conveyance route, and exerts control to feed the previously printed sheet and the subsequently printed sheet in an overlapped manner after the first conveyance route and the second conveyance route merge together.

Abstract: an image forming apparatus including; a non-inversion conveyance unit that conveys a sheet to a downstream without inverting through the image forming unit; an inversion conveyance unit that inverts the sheet with printing on one side and that conveys the sheet to an upstream; a first sheet inversion unit that is arranged on the inversion conveyance unit and inverts the front and back of the sheet conveyed by the inversion conveyance unit; a control unit that controls the image forming unit and the conveyance unit, wherein the control unit includes a single-sided print mode and a double-sided print mode, and at a breakpoint of jobs, the control unit discharges the sheet so as to provide charge polarity that does not electrostatically attract a sheet discharged just before the breakpoint and a sheet discharged just after the breakpoint at least in the double-sided print mode.

Abstract: An image forming apparatus includes a fixing side member disposed at a position on a fixing surface side of a sheet on which a toner image is formed; a back side supporting member that forms a fixing nip for conveying the sheet in a tightly sandwiching manner when the back side supporting member is in pressure contact with the fixing side member; and a voltage applying section that applies to both sides of the sheet passed through the fixing nip voltages opposite in polarity to surface potentials of the both sides.

Abstract: An image forming apparatus includes: a fixing unit that heats and presses a recording sheet having a toner image formed thereon, by means of a fixing nip portion to thereby fix the toner image to the recording sheet; a translation section that translates the fixing unit in a direction that is orthogonal to a conveying direction of the recording sheet; and a controlling section that controls the translation section so that the fixing unit is translated by a translation amount that is one-half of a value obtained by subtracting an image width of the toner image from a sheet width of the recording sheet.

Abstract: An image forming apparatus includes a fixing side member disposed at a position on a fixing surface side of a sheet on which a toner image is formed; a back side supporting member that forms a fixing nip for conveying the sheet in a tightly sandwiching manner when the back side supporting member is in pressure contact with the fixing side member; and a voltage applying section that applies to both sides of the sheet passed through the fixing nip voltages opposite in polarity to surface potentials of the both sides.

Abstract: An image forming apparatus includes: a fixing member; a moving section that moves the fixing member in a sheet width direction; a temperature detection section disposed at a position corresponding to an end portion of the fixing member, the temperature detection section moving together with the fixing member to detect a temperature of the end portion; and a control section that performs a first movement control and a second movement control on the basis of a result of a detection by the temperature detection section, the first movement control being intended to move the fixing member in the sheet width direction in a reciprocating manner with a predetermined cycle, the second movement control being intended to move the fixing member in the sheet width direction so that the temperature of the fixing member falls within a predetermined temperature range.

Abstract: An image forming apparatus including; a non-inversion conveyance unit that conveys a sheet to a downstream without inverting through the image forming unit; an inversion conveyance unit that inverts the sheet with printing on one side and that conveys the sheet to an upstream; a first sheet inversion unit that is arranged on the inversion conveyance unit and inverts the front and back of the sheet conveyed by the inversion conveyance unit; a control unit that controls the image forming unit and the conveyance unit, wherein the control unit includes a single-sided print mode and a double-sided print mode, and at a breakpoint of jobs, the control unit discharges the sheet so as to provide charge polarity that does not electrostatically attract a sheet discharged just before the breakpoint and a sheet discharged just after the breakpoint at least in the double-sided print mode.

Abstract: An image forming apparatus has an image forming unit that forms an image on a sheet, a fixing unit that performs fixing of the sheet on which the image is formed, a first conveyance route that has a reverse conveyance route and a second conveyance route that does not pass the reverse conveyance route, and a control unit that performs first control for conveying a previously printed sheet which is printed previously via the first conveyance route and second control for conveying a subsequently printed sheet which is printed subsequently via the second conveyance route, and exerts control to feed the previously printed sheet and the subsequently printed sheet in an overlapped manner after the first conveyance route and the second conveyance route merge together.

Abstract: An image forming apparatus includes: a fixing unit that heats and presses a recording sheet having a toner image formed thereon, by means of a fixing nip portion to thereby fix the toner image to the recording sheet; a translation section that translates the fixing unit in a direction that is orthogonal to a conveying direction of the recording sheet; and a controlling section that controls the translation section so that the fixing unit is translated by a translation amount that is one-half of a value obtained by subtracting an image width of the toner image from a sheet width of the recording sheet.

Abstract: An image forming apparatus includes: a fixing member; a moving section that moves the fixing member in a sheet width direction; a temperature detection section disposed at a position corresponding to an end portion of the fixing member, the temperature detection section moving together with the fixing member to detect a temperature of the end portion; and a control section that performs a first movement control and a second movement control on the basis of a result of a detection by the temperature detection section, the first movement control being intended to move the fixing member in the sheet width direction in a reciprocating manner with a predetermined cycle, the second movement control being intended to move the fixing member in the sheet width direction so that the temperature of the fixing member falls within a predetermined temperature range.

Abstract: Fixing belt is brought into pressure-contact with the surface of fixing roller such that fixing belt rotates according to rotation of fixing roller, thereby forming, between fixing belt and fixing roller, fixing nip portion through which recording sheets pass. A pressing area of an opposing surface of pressing member contacting the surface of fixing roller via fixing belt is smaller in each end portion of the opposing surface in the axis direction of fixing roller than in a central portion of the opposing surface in the axis direction of fixing roller. This makes speed of conveying recording sheets faster in each edge portion in the width direction perpendicular to a recording sheet conveyance direction than in a central portion in the width direction. Thus, creases of recording sheets can be prevented while a recording sheet passes through fixing nip portion between fixing roller and fixing belt mutually brought into pressure-contact.

Abstract: A first pad has a first nip forming surface which extends in a direction X. An angle formed between an end portion of the first nip forming surface and an XZ plane is smaller than an angle formed between a central portion of the first nip forming surface and the XZ plane, where the XZ plane is formed on a downstream side of the first nip forming surface. Thereby, a fixing device is provided which suppresses generation of wrinkles on a recording material when the fixing device fixes toner on the recording material and conveys it.

Abstract: A fixing device has a presser member, a slide member and a pressure belt. Both ends of the presser member are positioned outside both ends of the slide member. Both ends of the slide member are positioned outside both ends of the pressure belt. Thereby, the slide member and the pressure belt are improved in service life, so that the fixing device as a whole is improved in service life.

Abstract: An image forming apparatus includes a fixing device in which a width of a slide member is larger than a width of a pressurizing belt while both ends of the slide member are positioned outside of both ends of the pressurizing belt. The above-structured slide member makes it possible to prevent lubricant on the slide member from leaking out of the ends of the slide member and coming around the inner surface of the slide member, and thereby to prevent a pressing member beneath the slide member from swelling, resulting in avoidance of wrinkle generation on recording materials.

Abstract: A fixing device of the present invention includes a holding frame placed along a fixed pressing member. The holding frame includes a groove section having a recessed cross section and extending along the width direction of a sheet. The fixed pressing member is housed in the groove section. The fixed pressing member is pressed toward the rotor so that the rotor and the fixed pressing member are put in pressure contact with each other. A first engaging element is provided in a predetermined position on the bottom face of the groove section of the holding frame. A second engaging element which engages with the first engaging element is provided in a position on the fixed pressing member which corresponds to the positions of the first engaging element on the holding frame.

Abstract: A first pad has a first nip forming surface which extends in a direction X. An angle formed between an end portion of the first nip forming surface and an XZ plane is smaller than an angle formed between a central portion of the first nip forming surface and the XZ plane, where the XZ plane is formed on a downstream side of the first nip forming surface. Thereby, a fixing device is provided which suppresses generation of wrinkles on a recording material when the fixing device fixes toner on the recording material and conveys it.

Abstract: A fixing device has a heating roller and a pressure belt. Surface hardness of the pressure belt is higher than surface hardness of the heating roller. An overall length of the pressure belt is longer than an overall length of a rubber layer of the heating roller. Both ends of the pressure belt are positioned outside both ends of the rubber layer of the heating roller. Thereby, the heating roller is improved in service life, so that the fixing device as a whole is improved in service life.