Abstract: An image forming apparatus includes a fixing device including a fixing rotary body and a heater for heating the fixing rotary body. An opposed body contacts the fixing rotary body with releasable pressure therebetween to form a fixing nip therebetween through which a recording medium is conveyed. A heat shield is interposed between the heater and the fixing rotary body and movable in a circumferential direction of the fixing rotary body to shield the fixing rotary body from the heater in a variable circumferential direct heating span of the fixing rotary body where the heater is disposed opposite the fixing rotary body directly. A controller halts the heat shield instantly when a fault occurs during a print job.

Abstract: A fixing device includes a heater that heats a fixing rotator and includes a first heating portion and a second heating portion substantially aligned with the first heating portion in an axial direction of the fixing rotator. A multi-view thermopile array detects a temperature of an outer circumferential surface of the fixing rotator at a plurality of spots thereon. A heater controller controls the first heating portion and the second heating portion individually based on the temperature of the fixing rotator detected at the plurality of spots thereon. A recording medium conveyance controller determines whether or not to convey the recording medium to the fixing nip based on an increased temperature detected at at least one of the plurality of spots on the fixing rotator.

Abstract: A fixing device includes a fixing rotary body and a heater disposed opposite the fixing rotary body. A heat shield is movable in a circumferential direction of the fixing rotary body and interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater. An overheating suppressor is interposed between the heater and the heat shield to shield the heat shield from the heater. The heat shield includes an intermediate portion spanning in the circumferential direction of the fixing rotary body and movable between a shield position where the intermediate portion is disposed opposite the heater directly and a retracted position where the intermediate portion is disposed opposite the heater via the overheating suppressor.

Abstract: A fixing device includes a heat source; a fixing member looped into a generally cylindrical shape to rotate in a circumferential direction thereof and partially heated by the heat source and to heat a surface of a recording medium bearing an unfixed toner image to fix the unfixed toner image thereon in a fixing process; a rotary pressing member disposed facing the fixing member to form a nip therebetween, through which the recording medium is transported in a transport direction; and a rotation driver to rotate one of the fixing member and the pressing member. In a case in which the fixing member is halted for a reason other than the fixing process while power of the fixing device is on, electric power is not supplied to the heat source and the fixing member is rotated by a predetermined amount or more after the fixing member is halted.

Abstract: A pressure adjuster for changing pressure between a plurality of opposed bodies pressed against each other includes a cam rotatable in a given direction of rotation and having a top dead center on an outer circumferential surface thereof that is distanced farthest from a rotation axis of the cam. A driver is connected to the cam to drive and rotate the cam. A cam rest contacts the cam and is connected to one of the plurality of opposed bodies. A cam regulation assembly is connected to the cam to regulate rotation of the cam at least when the top dead center of the cam passes a contact position where the cam contacts the cam rest.

Abstract: A fixing device includes an endless belt or a fixing belt; a pressure member to contact an outer circumferential surface of the fixing belt; a nip forming member disposed at an interior side of the fixing belt and contacting the pressure member via the fixing belt; a heat source disposed at an interior side of the fixing belt to heat the fixing belt with radiant heat, a plurality of shielding members disposed between the heat source and the fixing belt and movable between a shielding position where the shielding member shields a non-sheet passing area on the fixing belt from the radiant heat from the heat source and a retracted position; and a controller to move the plurality of shielding members between the shielding position and the retracted position at a predetermined time.

Abstract: A fixing device includes a first heat generator and a second heat generator that heat a fixing rotator. A support is disposed inside the fixing rotator. A reflector is mounted on the support and interposed between the support and each of the first heat generator and the second heat generator to reflect light radiated from the first heat generator and the second heat generator toward the fixing rotator. The reflector includes a body mounted on the support and a shield portion projecting from the body toward the first heat generator and the second heat generator to shield the fixing rotator from the first heat generator and the second heat generator. The shield portion includes a wing disposed opposite a non-conveyance span of the fixing rotator in the axial direction thereof where a recording medium is not conveyed over the fixing rotator.

Abstract: A fixing device includes an endless belt rotatable in a predetermined direction of rotation and an opposed rotator contacting an outer circumferential surface of the endless belt. A nip formation pad, disposed opposite an inner circumferential surface of the endless belt, presses against the opposed rotator via the endless belt to form a fixing nip between the endless belt and the opposed rotator, through which a recording medium is conveyed. A belt holder contacts and rotatably supports a lateral end of the endless belt in an axial direction thereof. A ring is interposed between the belt holder and a lateral edge face of the endless belt. A restraint disposed opposite the ring contacts the ring to restrict movement of the ring in a radial direction of the endless belt within a trajectory of the lateral end of the rotating endless belt.

Abstract: A fixing device includes a fixing rotary body and a heater disposed opposite and heating the fixing rotary body. A nip formation assembly presses against an opposed body via the fixing rotary body to form a fixing nip between the fixing rotary body and the opposed body, through which a recording medium is conveyed. A movable heat shield movable in a circumferential direction of the fixing rotary body is interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater in a variable axial span of the fixing rotary body. A stationary heat shield, interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater, is disposed outboard from a lateral edge of a heat generator of the heater in an axial direction of the fixing rotary body.

Abstract: A fixing device includes a fixing rotator heated by a heater and a pressing rotator pressed against the fixing rotator to form a fixing nip therebetween, through which a recording medium bearing a toner image is conveyed. A heat shield interposed between the heater and the fixing rotator is movable in a circumferential direction of the fixing rotator to shield the fixing rotator from the heater in a variable axial shield span of the fixing rotator. The fixing rotator performs fixing rotation to convey the recording medium through the fixing nip while heating the recording medium and supplemental rotation other than fixing rotation. The heat shield moves to a decreased shield span position where the heat shield shields the fixing rotator from the heater in a decreased axial shield span of the fixing rotator during supplemental rotation thereof.

Abstract: A fixing device includes a fixing rotary body and a heater disposed opposite the fixing rotary body. A heat shield is movable in a circumferential direction of the fixing rotary body and interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater. An overheating suppressor is interposed between the heater and the heat shield to shield the heat shield from the heater. The heat shield includes an intermediate portion spanning in the circumferential direction of the fixing rotary body and movable between a shield position where the intermediate portion is disposed opposite the heater directly and a retracted position where the intermediate portion is disposed opposite the heater via the overheating suppressor.

Abstract: An image forming apparatus includes an image forming unit; an intermediate transfer member; a secondary transfer member to form a secondary transfer nip with the intermediate transfer member and the secondary transfer member; a biasing mechanism to bias the secondary transfer member toward the intermediate transfer member; a cam member rotatable between a first position, at which a predetermined space is formed in the secondary transfer nip, and a second position, at which the secondary transfer member and the intermediate transfer member contact each other; and a contact-separation controller configured to put the cam member in the first position before entry of the recording medium into the secondary transfer nip, rotate the cam member toward the second position when the recording medium enters the secondary transfer nip, and change a start timing of rotation of the cam member in accordance with a thickness of the recording medium.

Abstract: A fixing device includes a support member disposed to support a nip formation member on an inner peripheral surface of a fixing belt. The support member includes a parallel portion that supports the nip formation member and extends parallel to a sheet transport direction in a nip portion, and a rise portion that extends from the parallel portion in a direction drawn apart from the nip portion. The rise portion is inclined to the parallel portion such that an inclination direction of the rise portion is substantially parallel to a virtual straight line connecting a center of rotation of the fixing belt and an inlet point of the nip portion or falls within a range of rotational angles of ±15° by which the virtual straight line is rotated around the center of rotation of the fixing belt.

Abstract: A fixing device includes a first rotator and a second rotator pressed against the first rotator to form a fixing nip therebetween, through which a recording medium bearing a toner image is conveyed. A thermal insulation cover is disposed opposite the second rotator. A mover is connected to the second rotator to move the second rotator with respect to the first rotator. The mover is coupled with the thermal insulation cover to move the thermal insulation cover while retaining a predetermined interval between the thermal insulation cover and the second rotator.

Abstract: A fixing device includes a fixing rotator rotatable in a predetermined direction of rotation and a nip formation assembly contacting an inner circumferential surface of the fixing rotator. An opposed rotator presses against the nip formation assembly via the fixing rotator to form a fixing nip between the fixing rotator and the opposed rotator, through which a recording medium is conveyed. A support, disposed opposite the inner circumferential surface of the fixing rotator, supports the nip formation assembly. A heater, disposed opposite the inner circumferential surface of the fixing rotator, heats the fixing rotator. A reflector, disposed opposite an outer circumferential surface of the fixing rotator, reflects heat radiated from the fixing rotator onto the fixing rotator. The reflector spans a circumferential span of the fixing rotator where the fixing rotator is spaced apart from the support with a decreased interval therebetween.

Abstract: An image forming apparatus includes a first heater disposed opposite and heating at least a center of a fixing belt in an axial direction thereof and a second heater disposed opposite and heating at least a lateral end of the fixing belt in the axial direction thereof. A power supply supplies power to the first heater and the second heater. A controller that controls the power supply includes a calculator to calculate an elapsed time elapsed after at least one of the first heater and the second heater starts heating the fixing belt. The controller controls the power supply to supply power to the first heater and the second heater such that a power density of the second heater is greater than a power density of the first heater when the elapsed time calculated by the calculator is smaller than a predetermined time.

Abstract: An image forming apparatus includes: a belt unit that includes a belt-shaped image carrier stretched around and driven to rotate by a plurality of rollers; a belt tensioning unit that includes a tensioning member that is brought into contact with an image carrying surface of the belt-shaped image carrier and applies tension to the belt-shaped image carrier; and a cleaning unit that includes a cleaning member that is brought into contact with the image carrying surface of the belt-shaped image carrier and cleans the image carrying surface. The cleaning unit is supported by the belt tensioning unit in an attachable and detachable manner.

Abstract: A fixing device includes a fixing rotary body and a heater disposed opposite the fixing rotary body. A heat shield is movable in a circumferential direction of the fixing rotary body and interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater. An overheating suppressor is interposed between the heater and the heat shield to shield the heat shield from the heater. The heat shield includes an intermediate portion spanning in the circumferential direction of the fixing rotary body and movable between a shield position where the intermediate portion is disposed opposite the heater directly and a retracted position where the intermediate portion is disposed opposite the heater via the overheating suppressor.

Abstract: A fixing device includes a fixing rotator rotatable in a predetermined direction of rotation, a heater disposed opposite the fixing rotator to heat the fixing rotator, and an opposed rotator contacting an outer circumferential surface of the fixing rotator. A heat shield interposed between the heater and the fixing rotator shields the fixing rotator from the heater. A support supports the heat shield. The heat shield includes a first section supported by the support and having a decreased thermal conductivity and a second section abutting the first section in an axial direction of the heat shield and having an increased thermal conductivity greater than the decreased thermal conductivity of the first section.

Abstract: A fixing device includes a fixing rotator heated by a heater and a pressing rotator to press against the fixing rotator to form a fixing nip therebetween. A heating span adjuster, interposed between the heater and the fixing rotator, is movable in a circumferential direction of the fixing rotator. The heating span adjuster moves to a retracted position where the heating span adjuster allows the heater to heat the fixing rotator in an increased axial heating span of the fixing rotator after the heater starts heating the fixing rotator until the fixing rotator and the pressing rotator start conveying a recording medium through the fixing nip. The heating span adjuster at the retracted position is outboard from a circumferential, direct heating span of the fixing rotator where the heater heats the fixing rotator directly.