Abstract: An image forming apparatus including: an image forming portion that forms a toner image on a recording material; a fixing portion that has a heater unit including a heater and that fixes the toner image on the recording material, the heater being capable of changing a heat generating region; a control portion that controls the heater; and an image adding portion that adds a predetermined additional image to a desired image, wherein the control portion sets the heat generating region according to a width of the desired image in a direction perpendicular to the conveying direction or a width of the recording material in the direction perpendicular to the conveying direction, and the width of the predetermined additional image in the direction perpendicular to the conveying direction is equal to or less than the width of the heat generating region in the direction perpendicular to the conveying direction.

Abstract: An image heating apparatus includes: a tubular film; a heater disposed in an inner space of the film; a roller that is in contact with the outer surface of the film and forms a nip between the roller and the film together with the heater; and a holder including an adhesion portion to which the heater adheres through an adhesive and supporting the heater. The image heating apparatus heats, using heat of the heater, an image formed on a recording material held and conveyed by the nip in case where the roller rotates. The adhesion portion includes a surface having an uneven shape of projections and recesses repeating in each of a conveyance direction of the recording material and in a longitudinal direction of the heater perpendicular to the conveyance direction, and a depth of the projections and recesses is 50 ?m to 300 ?m.

Abstract: An image heating apparatus includes a heater having a first heating block and a second heating block, a heating rotating member to be heated by the heater, a pressure rotating member forming a nip portion for conveying a recording material between the pressure rotating member and the heating rotating member, first temperature detection elements and second temperature detection elements for detecting temperatures of the first heating block and second heating block respectively at positions farther from a recording material conveyance reference position than the first temperature detection elements. In the image heating apparatus, the first temperature detection elements are arranged on a side downstream of the heater in a recording material conveying direction, and the second temperature detection elements are arranged on upstream of the first temperature detection elements in the recording material conveying direction.

Abstract: In an image heating device including a heater including a substrate, a first conductor provided on the substrate, a second conductor provided at a position different from the first conductor on the substrate in a direction orthogonal to a longitudinal direction of the substrate, and a plurality of heat-generating resistors, each having the same shape and electrically connected in parallel between the first conductor and the second conductor on the substrate and a plurality of temperature detection elements for detecting a temperature of the heater and heating an image formed on a recording material by the heater, the plurality of temperature detection elements includes at least two temperature detection elements whose relative positions with respect to the closest heat-generating resistor in the plurality of heat-generating resistors are the same, respectively, the closest heat-generating resistors corresponding to the at least two temperature detection elements are independently controlled.

Abstract: An image heating apparatus includes a heater having a first heating block and a second heating block, a heating rotating member to be heated by the heater, a pressure rotating member forming a nip portion for conveying a recording material between the pressure rotating member and the heating rotating member, first temperature detection elements and second temperature detection elements for detecting temperatures of the first heating block and second heating block respectively at positions farther from a recording material conveyance reference position than the first temperature detection elements. In the image heating apparatus, the first temperature detection elements are arranged on a side downstream of the heater in a recording material conveying direction, and the second temperature detection elements are arranged on upstream of the first temperature detection elements in the recording material conveying direction.

Abstract: An image forming apparatus including: an image forming portion that forms a toner image on a recording material; a fixing portion that has a heater unit including a heater and that fixes the toner image on the recording material, the heater being capable of changing a heat generating region; a control portion that controls the heater; and an image adding portion that adds a predetermined additional image to a desired image, wherein the control portion sets the heat generating region according to a width of the desired image in a direction perpendicular to the conveying direction or a width of the recording material in the direction perpendicular to the conveying direction, and the width of the predetermined additional image in the direction perpendicular to the conveying direction is equal to or less than the width of the heat generating region in the direction perpendicular to the conveying direction.

Abstract: An image forming apparatus including: an image forming portion that forms a toner image on a recording material; a fixing portion that has a heater unit including a heater and that fixes the toner image on the recording material, the heater being capable of changing a heat generating region; a control portion that controls the heater; and an image adding portion that adds a predetermined additional image to a desired image, wherein the control portion sets the heat generating region according to a width of the desired image in a direction perpendicular to the conveying direction or a width of the recording material in the direction perpendicular to the conveying direction, and the width of the predetermined additional image in the direction perpendicular to the conveying direction is equal to or less than the width of the heat generating region in the direction perpendicular to the conveying direction.

Abstract: An image heating apparatus includes a heater having a first heating block and a second heating block, a heating rotating member to be heated by the heater, a pressure rotating member forming a nip portion for conveying a recording material between the pressure rotating member and the heating rotating member, first temperature detection elements and second temperature detection elements for detecting temperatures of the first heating block and second heating block respectively at positions farther from a recording material conveyance reference position than the first temperature detection elements. In the image heating apparatus, the first temperature detection elements are arranged on a side downstream of the heater in a recording material conveying direction, and the second temperature detection elements are arranged on a side upstream of the first temperature detection elements in the recording material conveying direction.

Abstract: In an image heating device including a heater including a substrate, a first conductor provided on the substrate, a second conductor provided at a position different from the first conductor on the substrate in a direction orthogonal to a longitudinal direction of the substrate, and a plurality of heat-generating resistors, each having the same shape and electrically connected in parallel between the first conductor and the second conductor on the substrate and a plurality of temperature detection elements for detecting a temperature of the heater and heating an image formed on a recording material by the heater, the plurality of temperature detection elements includes at least two temperature detection elements whose relative positions with respect to the closest heat-generating resistor in the plurality of heat-generating resistors are the same, respectively, the closest heat-generating resistors corresponding to the at least two temperature detection elements are independently controlled.

Abstract: An image heating apparatus includes a heater having a first heating block and a second heating block, a heating rotating member to be heated by the heater, a pressure rotating member forming a nip portion for conveying a recording material between the pressure rotating member and the heating rotating member, first temperature detection elements and second temperature detection elements for detecting temperatures of the first heating block and second heating block respectively at positions farther from a recording material conveyance reference position than the first temperature detection elements. In the image heating apparatus, the first temperature detection elements are arranged on a side downstream of the heater in a recording material conveying direction, and the second temperature detection elements are arranged on upstream of the first temperature detection elements in the recording material conveying direction.

Abstract: An image forming apparatus including: an image forming portion that forms a toner image on a recording material; a fixing portion that has a heater unit including a heater and that fixes the toner image on the recording material, the heater being capable of changing a heat generating region; a control portion that controls the heater; and an image adding portion that adds a predetermined additional image to a desired image, wherein the control portion sets the heat generating region according to a width of the desired image in a direction perpendicular to the conveying direction or a width of the recording material in the direction perpendicular to the conveying direction, and the width of the predetermined additional image in the direction perpendicular to the conveying direction is equal to or less than the width of the heat generating region in the direction perpendicular to the conveying direction.

Abstract: An image forming apparatus includes a device for forming a trace of an image fixing nip, primary transfer nip, secondary transfer nip or developing nip is formed, a detecting device for detecting a width of the nip from the trace of the nip, and a controller for controlling fixing, transferring, developing or image forming parameter in accordance with the nip width detected by the detecting device. Proper image forming conditions are provided against the change of the nip width.

Abstract: An image forming apparatus includes an image forming portion configured to form an image on a recording material, and a fixing portion including a first rotatable member and a second rotatable member, rotatable by rotation of the first rotatable member, and in contact with the first rotatable member. The fixing portion fixes the image on the recording material by heating the image while nipping and feeding the recording material, on which the image is formed, at a nip formed between the first rotatable member and the second rotatable member. A motor drives the first rotatable member, and torque detecting means detects a driving torque of the motor. On the basis of the driving torque detected by the torque detecting means, a controller controls a degree of temperature rise of the first rotatable member immediately before the recording material enters the nip.

Abstract: An image forming apparatus includes a device for forming a trace of a image fixing nip, primary transfer nip, secondary transfer nip or developing nip is formed, a detecting device for detecting a width of the nip from the trace of the nip, and a controller for controlling fixing, transferring, developing or image forming parameter in accordance with the nip width detected by the detecting device. Proper image forming conditions are provided against the change of the nip width.

Abstract: An image forming apparatus includes an image forming portion configured to form an image on a recording material; a fixing portion including a first rotatable member and a second rotatable member rotatable by rotation of the first rotatable member in contact with the first rotatable member and configured to fix the image on the recording material by heating the image while nipping and feeding the recording material on which the image is formed, at a nip formed between the first rotatable member and the second rotatable member; a motor configured to drive the first rotatable member; a torque detecting portion configured to detect a driving torque of the motor; and a controller. On the basis of the driving torque detected by the torque detecting means, the controller controls a degree of temperature rise of the first rotatable member immediately before the recording material enters the nip.

Abstract: An image forming apparatus includes a fixing unit having a rotating member with a surface layer, a pressing member that forms a fixing nip portion to sandwich and to transport a recording material with the rotating member, and a heater that heats the rotating member. A rotating member temperature sensor detects a temperature of the rotating member, and a wearing amount acquisition portion acquires a wearing amount of the surface layer of the rotating member. The wearing amount acquisition portion acquires the wearing amount corresponding to the temperature detected by the rotating member temperature sensor, and acquires the wearing amount per recording material. The wearing amount per recording material is different depending on the temperature detected by the rotating member temperature sensor. In addition, a control temperature setting portion sets a control temperature of the heater according to the wearing amount.

Abstract: A fixing apparatus fixes a toner image on a recording material by conveying and heating the recording material at a nip portion, and includes a first rotating member, a second rotating member configured to form the nip portion with the first rotating member, the first and second rotating members being arranged such that rotation of the second rotating member causes rotation of the first rotating member, a frame configured to support the second rotating member, so as to be rotatable and an opening and closing part arranged to open and close relative to the frame on the downstream side of the nip portion in the conveyance direction of the recoding material, the opening and closing part having a duct through which air flows.

Abstract: Provided is an image forming apparatus that prints an image on a recording material. The image forming apparatus includes: a fixing unit that fixes an image formed on a recording material onto the recording material; a temperature sensor that detects temperature of a rotating member of the fixing unit; a wearing amount acquisition portion that acquires a wearing amount of a surface layer of the rotating member corresponding to the detected temperature; and a control temperature setting portion that sets control temperature of a heater according to the wearing amount.

Abstract: A fixing device includes first and second members, a frame supporting the second member, and two pressure mechanisms provided on either end of the first member. The mechanism includes a lever having one end supported by the frame in a rotatable manner in a pressure direction, and a helical compression spring disposed between a first spring support provided on the other end of the lever and a second spring support on the frame. At least one of the first and second spring supports includes a first area and a second area closer to the spring in the axial direction than the first area, the first area is in contact with an area of the spring close to a winding end of the spring, and the second area is in contact with an area of the spring farther away from the winding end in a winding direction than the first area.

Abstract: An image forming apparatus for forming a toner image on a recording material has an image forming unit configured to form the toner image on the recording material; a fixing unit configured to fix the toner image on the recording material while heating and conveying the recording material bearing the toner image at a nip portion, the fixing unit including a heating rotation member and a roller forming the nip portion with the heating rotation member; and a voltage applying unit configured to apply a potential difference between a surface of the heating rotation member and a surface of the roller, wherein a plurality of print modes different in conveyance speed of the recording material at the nip portion are carried out, and wherein the voltage applying unit applies the potential difference smaller in a first print mode than the potential difference in a second print mode.