Abstract: An image forming apparatus includes a power controller that starts an examination mode by an external operation. The examination mode detects a temperature-resistance property of a resistive heat generator. The power controller supplies power at a predetermined power duty cycle to the resistive heat generator, The power controller obtains the power supplied to the resistive heat generator and a change in a temperature of the resistive heat generator, that is detected by a temperature detector, while the power controller supplies the power at the predetermined power duty cycle to the resistive heat generator. The power controller calculates the temperature-resistance property of the resistive heat generator based on the power and the change in the temperature that are obtained. The power controller adjusts a power duty cycle at which the power is supplied to the resistive heat generator based on the temperature-resistance property.

Abstract: An image forming apparatus includes a heating device including a heat generator and a resistance value identifier, a body, a resistance value acquisition unit, a detector to detect detachment and attachment of the heating device from and to the body, and an electric power controller. The resistance value identifier corresponds to a resistance value of the heat generator. The resistance value acquisition unit acquires the resistance value from the resistance value identifier. The electric power controller causes the resistance value acquisition unit to acquire the resistance value when the detector detects detachment and attachment of the heating device. The electric power controller changes a lighting duty of the heat generator when the acquired resistance value of the heat generator is different from the resistance value before the detector detects detachment and attachment of the heating device.

Abstract: An image forming apparatus includes a resistive heat generator, a temperature detector, and a power controller that detects a temperature-resistance property of the resistive heat generator before the resistive heat generator is used when the resistive heat generator is removably installed. The power controller obtains power supplied to the resistive heat generator and a change in a temperature of the resistive heat generator, that is detected by the temperature detector, while the power controller supplies the power at a predetermined power duty cycle for adjustment to the resistive heat generator. The power controller calculates the temperature-resistance property of the resistive heat generator based on the power and the change in the temperature that are obtained. The power controller adjusts a power duty cycle at which the power is supplied to the resistive heat generator in use of the resistive heat generator, based on the temperature-resistance property.

Abstract: An image forming apparatus includes a power controller that starts an examination mode by an external operation. The examination mode detects a temperature-resistance property of a resistive heat generator. The power controller supplies power at a predetermined power duty cycle to the resistive heat generator. The power controller obtains the power supplied to the resistive heat generator and a change in a temperature of the resistive heat generator, that is detected by a temperature detector, while the power controller supplies the power at the predetermined power duty cycle to the resistive heat generator. The power controller calculates the temperature-resistance property of the resistive heat generator based on the power and the change in the temperature that are obtained. The power controller adjusts a power duty cycle at which the power is supplied to the resistive heat generator based on the temperature-resistance property.

Abstract: An image forming apparatus includes a resistive heat generator and a power control device that controls power supplied to the resistive heat generator. The power control device supplies the power at a predetermined power duty cycle for adjustment to the resistive heat generator. The power control device adjusts a power duty cycle when the resistive heat generator is used.

Abstract: A fixing device includes a rotator, an endless belt, and a nip formation pad. The endless belt contacts the rotator and rotates in a direction of rotation. The nip formation pad contacts an inner circumferential surface of the endless belt to form a fixing nip between the endless belt and the rotator that presses the endless belt against the nip formation pad. The nip formation pad includes a slide layer, a base layer, and a lubricant holding layer. The slide layer contacts the endless belt. The base layer is disposed away from the endless belt. The lubricant holding layer is interposed between the slide layer and the base layer to hold a lubricant inside the lubricant holding layer and supply the lubricant to the slide layer. The slide layer has a porous structure including a plurality of through holes in a thickness direction of the slide layer.

Abstract: A fixing device includes a rotator, an endless belt, and a nip formation pad. The endless belt contacts the rotator and rotates in a direction of rotation. The nip formation pad contacts an inner circumferential surface of the endless belt to form a fixing nip between the endless belt and the rotator that presses the endless belt against the nip formation pad. The nip formation pad includes a slide layer, a base layer, and a lubricant holding layer. The slide layer contacts the endless belt. The base layer is disposed away from the endless belt. The lubricant holding layer is interposed between the slide layer and the base layer to hold a lubricant inside the lubricant holding layer and supply the lubricant to the slide layer. The slide layer has a porous structure including a plurality of through holes in a thickness direction of the slide layer.

Abstract: A fixing device includes a fixing rotator including a primary portion and a secondary portion disposed outboard from the primary portion in an axial direction of the fixing rotator. A pressure rotator contacts the fixing rotator to form a fixing nip between the fixing rotator and the pressure rotator, through which a recording medium is conveyed. A primary heater heats the primary portion of the fixing rotator. A secondary heater heats the secondary portion of the fixing rotator. A primary temperature detector is isolated from the fixing rotator and detects a temperature of the primary portion of the fixing rotator. A secondary temperature detector contacts the fixing rotator and detects a temperature of the secondary portion of the fixing rotator. The primary temperature detector has a thermal time constant that is smaller than a thermal time constant of the secondary temperature detector.

Abstract: A fixing device is removably installed inside an apparatus body including an apparatus guide. The fixing device includes a convex guide guided along the apparatus guide and a heater to heat a recording medium to fix a toner image on the recording medium. The heater includes a lateral end in a longitudinal direction of the heater. The lateral end is disposed inside the convex guide.

Abstract: A fixing device includes a fixing rotator including a primary portion and a secondary portion disposed outboard from the primary portion in an axial direction of the fixing rotator. A pressure rotator contacts the fixing rotator to form a fixing nip between the fixing rotator and the pressure rotator, through which a recording medium is conveyed. A primary heater heats the primary portion of the fixing rotator. A secondary heater heats the secondary portion of the fixing rotator. A primary temperature detector is isolated from the fixing rotator and detects a temperature of the primary portion of the fixing rotator. A secondary temperature detector contacts the fixing rotator and detects a temperature of the secondary portion of the fixing rotator. The primary temperature detector has a thermal time constant that is smaller than a thermal time constant of the secondary temperature detector.

Abstract: A fixing device is removably installed inside an apparatus body including an apparatus guide. The fixing device includes a convex guide guided along the apparatus guide and a heater to heat a recording medium to fix a toner image on the recording medium. The heater includes a lateral end in a longitudinal direction of the heater. The lateral end is disposed inside the convex guide.

Abstract: A fixing device includes a drive roller, a driven roller driven to rotate by the drive roller, and a braking force applicator. The driven roller presses against the drive roller to form an area of contact between the drive roller and the driven roller, through which a recording medium bearing a toner image passes. The braking force applicator applies a braking force to the driven roller to generate a shear force between the drive roller and the driven roller. The shear force acting between the drive roller and the driven roller when the drive roller and the driven roller rotate is in a range of from 15N to 25N.

Abstract: A separator for separating a recording medium from a fixing rotator includes a separation body including a front end and a conveyance path side face. The front end is disposed in proximity to an outer circumferential surface of the fixing rotator. The conveyance path side face faces a conveyance path where the recording medium is conveyed. At least one rotary separation aid projects beyond the conveyance path side face of the separation body toward the conveyance path. The rotary separation aid is rotated by the recording medium as the recording medium comes into contact with the rotary separation aid.

Abstract: A fixing device includes a first rotary body, a second rotary body to contact the first rotary body, and a plain bearing that supports the first rotary body or the second rotary body. One rotary body of the first rotary body and the second rotary body has an outer diameter increasing, while the other rotary body has an outer diameter decreasing, in a curved line from an axial center portion to axial end portions of the first rotary body and the second rotary body at least between the first rotary body and the second rotary body. A recording medium passes between the first rotary body and the second rotary body with a circumferential component of a shear force generated between the first rotary body and the second rotary body by use of the plain bearing being in a range of from 15N to 25N.

Abstract: An image forming apparatus includes a controller including a primary heating control portion that determines a first amount of power supplied to a heater based on a temperature of a fixing rotator detected by a temperature detector and controls the heater to perform a primary heating to heat the fixing rotator with the first amount of power, a secondary heating control portion that controls the heater to perform a secondary heating to heat the fixing rotator with a preset second amount of power, and a switch portion that controls the heater to switch between the primary heating and the secondary heating during an identical print job without changing a target temperature of the fixing rotator.

Abstract: A fixing device includes a drive roller, a driven roller driven to rotate by the drive roller, and a braking force applicator. The driven roller presses against the drive roller to form an area of contact between the drive roller and the driven roller, through which a recording medium bearing a toner image passes. The braking force applicator applies a braking force to the driven roller to generate a shear force between the drive roller and the driven roller. The shear force acting between the drive roller and the driven roller when the drive roller and the driven roller rotate is in a range of from 15N to 25N.

Abstract: A fixing device includes a first rotary body, a second rotary body to contact the first rotary body, and a plain bearing that supports the first rotary body or the second rotary body. One rotary body of the first rotary body and the second rotary body has an outer diameter increasing, while the other rotary body has an outer diameter decreasing, in a curved line from an axial center portion to axial end portions of the first rotary body and the second rotary body at least between the first rotary body and the second rotary body. A recording medium passes between the first rotary body and the second rotary body with a circumferential component of a shear force generated between the first rotary body and the second rotary body by use of the plain bearing being in a range of from 15N to 25N.

Abstract: A separator for separating a recording medium from a fixing rotator includes a separation body including a front end and a conveyance path side face. The front end is disposed in proximity to an outer circumferential surface of the fixing rotator. The conveyance path side face faces a conveyance path where the recording medium is conveyed. At least one rotary separation aid projects beyond the conveyance path side face of the separation body toward the conveyance path. The rotary separation aid is rotated by the recording medium as the recording medium comes into contact with the rotary separation aid.

Abstract: A fixing device temperature control method is performed by a fixing device including a heat conductor contacting and heating an unfixed toner image formed on a recording medium, a heater disposed opposite and heating the heat conductor, and a pressing roller pressed against the heat conductor to form a fixing nip between the heat conductor and the pressing roller through which the recording medium is conveyed. The method includes detecting a temperature of the pressing roller and controlling an input voltage to the heater based on the detected temperature of the pressing roller to maintain a temperature of the recording medium discharged from the fixing nip at a target temperature.

Abstract: A fixing device includes a first rotator, a second rotator pressed against the first rotator, and a heater to heat the first rotator. The heater includes an elongated substrate extending in an axial direction of the first rotator, a heat generator disposed on a surface of the substrate facing the first rotator, at a position downstream in a rotational direction of the first rotator, a plurality of first conduction paths connected to the heat generator and grounded downstream of the heat generator in the rotational direction of the first rotator, and a second conduction path on which the plurality of first conduction paths are grounded. The heat generator has a heat-generating area divided into a plurality of sub-heat-generating areas in the axial direction of the first rotator. The plurality of sub-heat-generating areas are grounded on the second conduction path via the plurality of first conduction paths.