Abstract: A fixing apparatus having a first rotation member, an elongated heater having a heat generating member and a substrate on which the heat generating member is provided and being disposed in an internal space of the first rotation member, a heater holder that holds the heater, a stay that supports the heater holder, a sliding sheet being disposed between the heater and the first rotation member and sliding on an inner circumferential surface of the first rotation member, and a second rotation member forming a nip portion with the heater through the first rotation member, and, in the nip portion, a toner image formed on a recording material being heated and fixed, in which, when a longitudinal direction of a surface of the substrate on which the heat generating member is provided, a transverse direction that is orthogonal to the longitudinal direction.

Abstract: A fixing apparatus includes a first rotary member, a nip forming unit including a heater and a holder member, a second rotary member, and a support member. The holder member includes a first surface configured to support the heater and provided on the nip portion side of the holder member in an orthogonal direction orthogonal to both of a longitudinal direction and a short direction, a second surface provided on a side of the holder member opposite to the first surface in the orthogonal direction and configured to abut a first abutting portion of the support member and abut a second abutting portion of the support member, and a rib portion provided to project from the second surface and extend in the short direction throughout at least a range in the short direction where the first surface is provided.

Abstract: A fixing apparatus includes a first rotary member, a nip forming unit including a heater and a holder member, a second rotary member, and a support member. The holder member includes a first surface configured to support the heater and provided on the nip portion side of the holder member in an orthogonal direction orthogonal to both of a longitudinal direction and a short direction, a second surface provided on a side of the holder member opposite to the first surface in the orthogonal direction and configured to abut a first abutting portion of the support member and abut a second abutting portion of the support member, and a rib portion provided to project from the second surface and extend in the short direction throughout at least a range in the short direction where the first surface is provided.

Abstract: An image heating device comprising: a first rotating member, a heater, a heater holder, and a second rotating member, wherein the heater holder has a flat surface portion provided downstream of the heater in a conveying direction of a recording material, the flat surface portion being in contact with the inner peripheral surface of the first rotating member, wherein the flat surface portion has a first region and a second region in a longitudinal direction, wherein the first region includes a region corresponding to a region of a nip portion through which a central portion of the recording material passes, and the second region is a region on an end portion side from the first region in the longitudinal direction, and wherein in the conveying direction, the downstream end portion of the second region is located upstream of the downstream end portion of the first region.

Abstract: An image forming apparatus includes a first determining portion for determining the presence of a first image with at least a first number of pixels having a density-related value of at least a predetermined value continuously arrayed in a subscanning direction, and with at least a second, greater, number of pixels having the density-related value of at least the predetermined value continuously arrayed in a main scanning direction. It also includes a second determining portion for determining a target temperature at which to maintain a fixing portion based on the presence of the first image, when a determination result indicates the presence of the first image, or based on a density-related value of a second image different from the first image, when the determination result indicates the absence of the first image. The apparatus controls power to the fixing portion to maintain its temperature at the determined target temperature.

Abstract: An image forming apparatus, including: determining presence or absence of a first image in which at least a first number of pixels each having a density-related value are continuously arrayed in a subscanning direction, and in which at least a second number of pixels each having the density-related value are continuously arrayed in a main scanning direction, the second number being greater than the first number; determining a target temperature based on the presence of the first image when a determination result indicates the presence of the first image, or determine the target temperature based on a density-related value of a second image that is different from the first image when the determination result indicates the absence of the first image; and controlling power to be supplied to a fixing portion so that a temperature of the fixing portion is maintained at the target temperature.

Abstract: There is provided an image forming apparatus including a configuration in which a voltage of a polarity opposite to a toner charging polarity is applied. In the image forming apparatus, a guide region of a pre-transfer guide is located on a photosensitive drum side with respect to a common tangent line of a photosensitive drum and a development roller to reduce contamination of the pre-transfer guide and prevent contamination of recording materials.

Abstract: An image forming apparatus includes a discharging device for discharging the drum at a discharging portion opposing the surface of the drum; and a control unit for executing, during non-image formation, a cleaning operation for transferring the toner deposited on the transfer member onto the drum by applying a voltage from transfer voltage source to the transfer member. The control unit does not effect discharge by the discharging device for at least a region of the drum where a transfer voltage for transferring a normal-polarity toner of the toner deposited on the transfer member onto the drum is applied to the transfer member in the cleaning operation, and then passes the region of the drum through the charging portion in a state in which a voltage larger than a surface potential of the drum in a normal polarity side is applied to the charging member.

Abstract: There is provided an image forming apparatus including a configuration in which a voltage of a polarity opposite to a toner charging polarity is applied. In the image forming apparatus, a guide region of a pre-transfer guide is located on a photosensitive drum side with respect to a common tangent line of a photosensitive drum and a development roller to reduce contamination of the pre-transfer guide and prevent contamination of recording materials.

Abstract: An image forming apparatus includes a developing unit which develops a toner image on a surface of a photosensitive member and which collects toner which remains on the surface of the photosensitive member after the developed toner image is transferred to a transfer member. The image forming apparatus includes a controller configured to determine whether a cleaning operation of cleaning the surface of the photosensitive member is to be performed after an image forming operation is performed or control a period of time in which the cleaning operation is performed in accordance with a measured downtime of the image forming apparatus which is a period of time after the image forming operation is terminated and before a next image forming operation is started.

Abstract: An image heating device includes a rotator, a heater including a heat generating resistor, a connector electrically connected to the heater, and a power interrupting unit that detects an abnormal temperature rise of the heater and interrupt supply of the power to the heater. The power interrupting unit includes a first terminal and a second terminal, a first conductive sheet metal that electrically connects the connector to the first terminal, a second conductive sheet metal that to electrically connects the connector to the second terminal via the heat generating resistor, a length of the second conductive sheet metal being different from a length of the first conductive sheet metal in the longitudinal direction of the heater, and a supporting member supporting the heater and including a regulation portion that regulates rotation of the power interrupting unit.

Abstract: An image forming apparatus includes a discharging device for discharging the drum at a discharging portion opposing the surface of the drum; and a control unit for executing, during non-image formation, a cleaning operation for transferring the toner deposited on the transfer member onto the drum by applying a voltage from transfer voltage source to the transfer member. The control unit does not effect discharge by the discharging device for at least a region of the drum where a transfer voltage for transferring a normal-polarity toner of the toner deposited on the transfer member onto the drum is applied to the transfer member in the cleaning operation, and then passes the region of the drum through the charging portion in a state in which a voltage larger than a surface potential of the drum in a normal polarity side is applied to the charging member.

Abstract: An image forming apparatus includes a discharging device for discharging the drum at a discharging portion opposing the surface of the drum; and a control unit for executing, during non-image formation, a cleaning operation for transferring the toner deposited on the transfer member onto the drum by applying a voltage from transfer voltage source to the transfer member. The control unit does not effect discharge by the discharging device for at least a region of the drum where a transfer voltage for transferring a normal-polarity toner of the toner deposited on the transfer member onto the drum is applied to the transfer member in the cleaning operation, and then passes the region of the drum through the charging portion in a state in which a voltage larger than a surface potential of the drum in a normal polarity side is applied to the charging member.

Abstract: An image forming apparatus includes a discharging device for discharging the drum at a discharging portion opposing the surface of the drum; and a control unit for executing, during non-image formation, a cleaning operation for transferring the toner deposited on the transfer member onto the drum by applying a voltage from transfer voltage source to the transfer member. The control unit does not effect discharge by the discharging device for at least a region of the drum where a transfer voltage for transferring a normal-polarity toner of the toner deposited on the transfer member onto the drum is applied to the transfer member in the cleaning operation, and then passes the region of the drum through the charging portion in a state in which a voltage larger than a surface potential of the drum in a normal polarity side is applied to the charging member.

Abstract: A relationship 150?Rs (?)/Rm (?)?4000 is established in an environment of a temperature of 15° C. and a humidity of 10% in a case where a surface resistance of a transfer roller is Rs (?) when a current is fed between a pair of electrodes facing each other in an axial direction of the transfer roller and arranged on a surface of the transfer roller with an interval of 5 mm therebetween, the electrodes having a width of 20 mm in a circumferential direction of the transfer roller in a state of being arranged on the transfer roller, and in a case where a combined resistance of a first layer and a second layer is Rm (?) when the current is fed from a core portion to an outer peripheral surface of the second layer.

Abstract: An image forming apparatus includes an image bearing member; a developing device; a transfer member; a contact member provided downstream of the transfer member and upstream of the developing device with respect to a movement direction of a surface of the image bearing member and contacting the image bearing member at a contact portion, wherein the surface of the image bearing member passed through a transfer portion reaches the contact portion without being cleaned, a detecting portion for detecting a size of the sheet; and a controller for executing an operation in a cleaning mode for cleaning the contact member. The controller executes the operation in the cleaning mode when the controller discriminates that the size of the sheet detected by the detecting portion is smaller than a size of the toner image.

Abstract: There is provided an image forming apparatus including a configuration in which a voltage of a polarity opposite to a toner charging polarity is applied. In the image forming apparatus, a guide region of a pre-transfer guide is located on a photosensitive drum side with respect to a common tangent line of a photosensitive drum and a development roller to reduce contamination of the pre-transfer guide and prevent contamination of recording materials.

Abstract: An image heating device includes a rotator, a heater including a heat generating resistor, a connector electrically connected to the heater, and a power interrupting unit that detects an abnormal temperature rise of the heater and interrupt supply of the power to the heater. The power interrupting unit includes a first terminal and a second terminal, a first conductive sheet metal that electrically connects the connector to the first terminal, a second conductive sheet metal that to electrically connects the connector to the second terminal via the heat generating resistor, a length of the second conductive sheet metal being different from a length of the first conductive sheet metal in the longitudinal direction of the heater, and a supporting member supporting the heater and including a regulation portion that regulates rotation of the power interrupting unit.

Abstract: An image forming apparatus includes a developing unit which develops a toner image on a surface of a photosensitive member and which collects toner which remains on the surface of the photosensitive member after the developed toner image is transferred to a transfer member. The image forming apparatus includes a controller configured to determine whether a cleaning operation of cleaning the surface of the photosensitive member is to be performed after an image forming operation is performed or control a period of time in which the cleaning operation is performed in accordance with a measured downtime of the image forming apparatus which is a period of time after the image forming operation is terminated and before a next image forming operation is started.

Abstract: A relationship 150?Rs (?)/Rm (?)?4000 is established in an environment of a temperature of 15° C. and a humidity of 10% in a case where a surface resistance of a transfer roller is Rs (?) when a current is fed between a pair of electrodes facing each other in an axial direction of the transfer roller and arranged on a surface of the transfer roller with an interval of 5 mm therebetween, the electrodes having a width of 20 mm in a circumferential direction of the transfer roller in a state of being arranged on the transfer roller, and in a case where a combined resistance of a first layer and a second layer is Rm (?) when the current is fed from a core portion to an outer peripheral surface of the second layer.