Abstract: An image forming apparatus includes an image forming device to form a cleaning toner image in a cleaning region on a cleaning sheet and a check toner image in a check region on the cleaning sheet. The image forming apparatus further includes a fixing device including a first rotator and a heater to heat the first rotator to a cleaning temperature that is lower than a fixing temperature to which the first rotator is heated in a print job and higher than a cold offset temperature at which toner adheres to the first rotator by cold offset. Each of the cleaning region and the check region has a length greater than a circumferential length of the first rotator. The cleaning region and the check region are disposed at a leading section and a trailing section of the cleaning sheet in a cleaning sheet conveyance direction, respectively.

Abstract: A fixing unit includes an endless belt accommodating a heat source inside a loop formed by the endless belt, a rotary pressing member rotating in contact with the endless belt in a pressure contact section, and a heat transfer member secured to a side plate within the loop of the endless belt to support and heat the endless belt with heat conducted from the heat source. The heat transfer member has an opening opposite the rotary pressing member. A securing member is disposed in the opening of the heat transfer member in pressure contact with the rotary pressing member via the endless belt. The heat transfer member and the securing member collectively include a pair of latching parts to firmly connect the heat transfer member and the securing member with each other when one of the latching parts is fitted to the other one of the latching parts.

Abstract: An image forming apparatus includes a controller including a primary heating control portion to control a heater to perform a primary heating to heat a fixing rotator with a first amount of power determined based on a temperature of the fixing rotator, a secondary heating control portion to control the heater to perform a secondary heating to heat the fixing rotator with a preset second amount of power, and a switch portion to control the heater to switch between the primary heating and the secondary heating during an identical print job and to perform at least one of a primary switching from the primary heating to the secondary heating and a secondary switching from the secondary heating to the primary heating at a time different from a preset control cycle that defines a power supply time in the primary heating and the secondary heating.

Abstract: An image forming apparatus includes an image forming device to form a cleaning toner image in a cleaning region on a cleaning sheet and a check toner image in a check region on the cleaning sheet. The image forming apparatus further includes a fixing device including a first rotator and a heater to heat the first rotator to a cleaning temperature that is lower than a fixing temperature to which the first rotator is heated in a print job and higher than a cold offset temperature at which toner adheres to the first rotator by cold offset. Each of the cleaning region and the check region has a length greater than a circumferential length of the first rotator. The cleaning region and the check region are disposed at a leading section and a trailing section of the cleaning sheet in a cleaning sheet conveyance direction, respectively.

Abstract: A fixing device, including a fixing member; an opposing member contacting the fixing member to form a fixing nip; plural separation assisting members; a contact direction biasing member contacting an end of the auxiliary separation members to the surface of the fixing member; a contact and release switching member switching contacting the end of the auxiliary separation members to the surface of the fixing member and releasing the end of the auxiliary separation members therefrom; a fixing exit guide member guiding a recording medium to a discharge direction and separated from the fixing member by the separation assisting member; a first rotating member near the auxiliary separation members downstream from an end thereof; and a second rotating member guiding a recording medium guided by the fixing exit guide member in the recording medium conveyance direction while rotating.

Abstract: A fixing unit includes an endless belt unit accommodating a heat source, a pressure roller to rotate in contact with the fixing belt unit forming a pressure border therebetween, and a heat transfer member heated by the heat source to heat the fixing belt unit. The heat transfer member is secured inside an inner circumferential surface of the fixing belt unit and supports the fixing belt unit. A fixed member is secured inside the inner circumferential surface of the fixing belt unit and is pressed against the pressure roller via the fixing belt unit. The heat transfer member has at least one convex portion partially formed in an outer circumferential surface of the heat transfer member in a rotational direction of the fixing belt unit and a longitudinal direction of the heat transfer member to narrow a gap formed between the heat transfer member and the fixing belt unit.

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: An image forming apparatus includes a controller including a primary heating control portion to control a heater to perform a primary heating to heat a fixing rotator with a first amount of power determined based on a temperature of the fixing rotator, a secondary heating control portion to control the heater to perform a secondary heating to heat the fixing rotator with a preset second amount of power, and a switch portion to control the heater to switch between the primary heating and the secondary heating during an identical print job and to perform at least one of a primary switching from the primary heating to the secondary heating and a secondary switching from the secondary heating to the primary heating at a time different from a preset control cycle that defines a power supply time in the primary heating and the secondary heating.

Abstract: An image forming apparatus includes an image forming unit to form a toner image on a recording medium and a fixing device. The fixing device includes a fixing belt to fix a toner image onto a recording medium transported to a fixing nip, a pressing member pressed against the fixing belt to form the fixing nip therebetween, a heating roller accommodating a heater to heat the fixing belt. A holder is provided to hold the heater at one end of the heater. An inner diameter of the heating roller and an outer diameter of the holder are substantially the same, and the heating roller and the holder partially overlap with each other in an axial direction of the heating roller. The interior and the exterior of the heating roller are preferably insulated by the heating roller and the holder by a prescribed degree not to change air pressure in the heating roller.

Abstract: A mechanism for guiding a recording medium into a nip formed between a first rotary member subjected to heating, and a second rotary member pressed against the first rotary member includes a guide member and a biasing member. The guide member is disposed upstream from the nip to guide the recording medium therealong. The biasing member is connected to the guide member to mechanically bias the guide member. The guide member is subjected to a constant biasing force from the biasing member and to a pressure force from the recording medium. The pressure force is opposite the biasing force and variable with a stiffness of the recording medium being guided. The guide member is movable to different operational positions depending on the biasing and pressure forces acting thereon.

Abstract: A fixing device includes a first opposed body and a second opposed body pressed against the first opposed body. A resilient member exerts a resilient bias to the second opposed body that presses the second opposed body against the first opposed body. A lever assembly is swingable to move the second opposed body against the resilient bias exerted by the resilient member between at least a reduced pressure position where the second opposed body presses against the first opposed body with reduced pressure therebetween and an enhanced pressure position where the second opposed body presses against the first opposed body with enhanced pressure therebetween. A resistance applier engages the lever assembly to exert drag on the lever assembly when the lever assembly moves the second opposed body from the reduced pressure position to the enhanced pressure position.

Abstract: A fixing device includes at least one separator including a pawl separatably contacting a fixing rotary body to separate a recording medium discharged from a fixing nip formed between the fixing rotary body and a pressing rotary body from the fixing rotary body; at least one first rotary body rotatably supported by the at least one separator to contact and guide the recording medium separated by the pawl in a recording medium conveyance direction; at least one second rotary body disposed downstream from the first rotary body in the recording medium conveyance direction to contact and guide the recording medium guided by the first rotary body in the recording medium conveyance direction; and at least one brush mounted on an outer circumferential surface of at least one of the first rotary body and the second rotary body.

Abstract: A guide device includes a fixing exit guide, a first rotary body, a second rotary body disposed downstream from the first rotary body in a recording medium conveyance direction and partially protruding from a guide face through a slot of the fixing exit guide to contact and support an image side of a recording medium conveyed over the second rotary body, and at least one guide rib mounted on the guide face of the fixing exit guide and extending substantially in the recording medium conveyance direction. The guide rib includes a contact face contacting the image side of the recording medium and a downstream end disposed downstream from the contact face in the recording medium conveyance direction to overlap the second rotary body in cross-section taken along a direction orthogonal to an axial direction of the second rotary body.

Abstract: An image forming apparatus includes an image forming unit to form a toner image on a recording medium and a fixing device. The fixing device includes a fixing belt to fix a toner image onto a recording medium transported to a fixing nip, a pressing member pressed against the fixing belt to form the fixing nip therebetween, a heating roller accommodating a heater to heat the fixing belt. A holder is provided to hold the heater at one end of the heater. An inner diameter of the heating roller and an outer diameter of the holder are substantially the same, and the heating roller and the holder partially overlap with each other in an axial direction of the heating roller. The interior and the exterior of the heating roller are preferably insulated by the heating roller and the holder by a prescribed degree not to change air pressure in the heating roller.

Abstract: A fixing unit includes an endless belt unit accommodating a heat source, a pressure roller to rotate in contact with the fixing belt unit forming a pressure border therebetween, and a heat transfer member heated by the heat source to heat the fixing belt unit. The heat transfer member is secured inside an inner circumferential surface of the fixing belt unit and supports the fixing belt unit. A fixed member is secured inside the inner circumferential surface of the fixing belt unit and is pressed against the pressure roller via the fixing belt unit. The heat transfer member has at least one convex portion partially formed in an outer circumferential surface of the heat transfer member in a rotational direction of the fixing belt unit and a longitudinal direction of the heat transfer member to narrow a gap formed between the heat transfer member and the fixing belt unit.

Abstract: A fixing unit includes an endless belt accommodating a heat source inside a loop formed by the endless belt, a rotary pressing member rotating in contact with the endless belt in a pressure contact section, and a heat transfer member secured to a side plate within the loop of the endless belt to support and heat the endless belt with heat conducted from the heat source. The heat transfer member has an opening opposite the rotary pressing member. A securing member is disposed in the opening of the heat transfer member in pressure contact with the rotary pressing member via the endless belt. The heat transfer member and the securing member collectively include a pair of latching parts to firmly connect the heat transfer member and the securing member with each other when one of the latching parts is fitted to the other one of the latching parts.

Abstract: A fixing device is disclosed, including: a fixing rotative body, a heat source, and a control part. The control part conducts a printing temperature control which varies an ON ratio per unit time of the heat source based on a detection result of the temperature detecting part to maintain a printing target temperature in a printing state, conducts a waiting temperature control which performs an ON/OFF control based on the detection result of the temperature detecting part to maintain a waiting target temperature in a waiting state after a printing operation ends, and conducts a forcible ON control which forcibly turns on the heat source for a predetermined time before starting the ON/OFF control when the detection result of the temperature detecting part after the printing operation ends is lower than the waiting target temperature.

Abstract: A fixing device includes a separator presser that presses against a plurality of separators to separate the plurality of separators from a fixing rotary body that contacts an opposed rotary body to form a fixing nip therebetween through which a recording medium bearing a toner image passes. A single driver is connected to the separator presser to separate the separator presser from the plurality of separators. An entering recording medium detector is disposed upstream from the fixing nip in a conveyance direction of the recording medium to detect the recording medium. A controller is connected to the driver to control the driver based on a detection signal sent from the entering recording medium detector to change a contact time period for which the plurality of separators contacts the fixing rotary body.

Abstract: A fixing device includes a temperature controller that controls a temperature of a fixing rotary body based on the temperature of the fixing rotary body detected by a temperature detector so as to heat the fixing rotary body to a plurality of preset target temperatures that includes a first target standby temperature, a target fixing temperature, a target idle temperature, and a second target standby temperature. When the target fixing temperature is lower than the first target standby temperature, the temperature controller separates a pressing rotary body from the fixing rotary body to idle the fixing rotary body for a predetermined idle time period before a fixing operation starts. After the fixing operation, the temperature controller controls a heater to change the temperature of the fixing rotary body to the second target standby temperature.

Abstract: A fixing device includes a first opposed body and a second opposed body pressed against the first opposed body. A resilient member exerts a resilient bias to the second opposed body that presses the second opposed body against the first opposed body. A lever assembly is swingable to move the second opposed body against the resilient bias exerted by the resilient member between at least a reduced pressure position where the second opposed body presses against the first opposed body with reduced pressure therebetween and an enhanced pressure position where the second opposed body presses against the first opposed body with enhanced pressure therebetween. A resistance applier engages the lever assembly to exert drag on the lever assembly when the lever assembly moves the second opposed body from the reduced pressure position to the enhanced pressure position.