Abstract: An image forming apparatus includes: a fixing device having a heating member, a heat source, a rotating member, and a temperature sensor; and a control device configured to control the heat source, wherein, in a case of a low temperature state where the temperature of the heating member is lower than a predetermined temperature, the control device to control the heat source such that the temperature of the heating member rises with a gradient equal to or greater than a predetermined value, and wherein, in a case of a high temperature state where the temperature of the heating member at the print-instruction receiving time is equal to or higher than the predetermined temperature, the control device to control the heat source such that the temperature of the heating member rises with a gradient smaller than that in the normal mode.

Abstract: A fixing device for thermally fixing a developing agent image to a sheet includes: a flexible tubular member having an inner peripheral surface defining an internal space; a heater; a nip member being in sliding contact with the inner peripheral surface of the flexible tubular member and having an electrically conductive surface; a stay supporting the nip member and being electrically conductive and electrically connected to the electrically conductive surface; a backup member nipping the flexible tubular member in cooperation with the nip member; a supporting member supporting the nip member and the stay, the supporting member being movable relative to the backup member; and a first grounding member disposed to be in contact with the stay for grounding the stay, the first grounding member being supported to the supporting member such that the first grounding member is integrally movable with the supporting member.

Abstract: A fixing device may include first and second fixing members arranged to form a nip portion, an urging member that provides an urging force to urge the first fixing member toward the second fixing member, a change member configured to change a width of the nip portion from a first nip width to a second nip width by applying a pressing force to the first fixing member against the urging force of the urging member and change the width of the nip portion from the second nip width to the first nip width by releasing the pressing force, and a restriction portion configured to restrict movement of the first fixing member and restrict a maximum value of the first nip width of the nip portion while the pressing force against the urging force is released.

Abstract: An image forming apparatus includes: a fixing device having a heat source, a heating member, and a backup member; a temperature detecting member; a driving source configured to rotate at least one of the heating member and the backup member; a transmitting mechanism configured to transmit a driving force of the driving source; and a control device configured to control the heat source and the driving source, wherein, after a power is turned on, the control device turns on the heat source before the driving source is driven for the first time, and wherein, when at least one of a condition, where the temperature detected by the temperature detecting member becomes a first temperature, and a condition where a predetermined period elapses after the power is turned on, is satisfied, the control device turns off the heat source and then drives the driving source.

Abstract: A fixing device for thermally fixing a developing agent image to a sheet includes: a flexible tubular member having an inner peripheral surface and circularly moving in a moving direction while the developing agent image is thermally fixed; a heater; a nip member being in sliding contact with the tubular member; a backup member nipping the tubular member in cooperation with the nip member; a stay covering the heater and supporting the nip member; an electric component positioned opposite to the heater with respect to the stay; and a frame supporting the electric component. The frame includes: an isolating portion interposed between the tubular member and the electric component for isolating the electric component from the tubular member; and a guide portion guiding the inner peripheral surface of the tubular member while the flexible tubular member is moving in the moving direction.

Abstract: A fixing device for thermally fixing a developing agent image to a sheet includes: a flexible tubular member having an inner peripheral surface and circularly moving in a moving direction while the developing agent image is thermally fixed; a heater; a nip member being in sliding contact with the tubular member; a backup member nipping the tubular member in cooperation with the nip member; a stay covering the heater and supporting the nip member; an electric component positioned opposite to the heater with respect to the stay; and a frame supporting the electric component. The frame includes: an isolating portion interposed between the tubular member and the electric component for isolating the electric component from the tubular member; and a guide portion guiding the inner peripheral surface of the tubular member while the flexible tubular member is moving in the moving direction.

Abstract: A fixing device configured to heat-fix a developer image on a recording sheet, the fixing device includes: a flexible cylindrical member; a nip member configured to slidingly contact an inner peripheral surface of the cylindrical member; a heating member that is arranged at an inside of the cylindrical member and is configured to heat the nip member; a stay configured to support the nip member with surrounding the heating member; a backup member configured to interpose the cylindrical member between the nip member and the backup member; a cover member that is arranged at the inside of the cylindrical member and is configured to cover the stay from an opposite side to the heating member; and a first support member configured to support the cover member and form a gap between the stay and the cover member.

Abstract: A fixing device includes: a flexible tubular member defining an internal space and extending in an axial direction; a first fixing member disposed within the internal space; and a second fixing member configured to nip the flexible tubular member in cooperation with the first fixing member. The flexible tubular member includes a metal base tube having an outer peripheral surface configured of a first area and a second area other than the first area in the axial direction. The first area has a 10-point average roughness of larger than 3 ?m, and the second area has a 10-point average roughness of equal to or smaller than 3 ?m.

Abstract: A fixing device includes: an endless fusing belt; a heater; a nip member; and a backup member. The endless fusing belt has a width in a widthwise direction. The nip member is disposed spaced apart from the heater. The nip member has a contact surface. The contact surface has widthwise end portions in the widthwise direction. The backup member is configured to nip the fusing belt in cooperation with the nip member. The fusing belt is configured to move in a moving direction at a position where the fusing belt is nipped between the nip member and the backup member. The contact surface has at least two grooves one formed in corresponding one of the widthwise end portions and another formed in the other of the widthwise end portions and extending at an angle equal to or smaller than 10 degrees with respect to the moving direction.

Abstract: A fixing device includes a heating element extending in a first direction and configured to generate heat, a nip member extending along the heating element in the first direction and configured to receive radiant heat from the heating element, an endless belt extending along the heating element in the first direction, and a backup member extending along the heating element in the first direction. The endless belt is configured to rotate. The endless belt surrounds the heating element and the nip member. The backup member nips the endless belt in cooperation with the nip member. The nip member includes a main portion facing in a second direction perpendicular to the first direction and a particular holding portion holding the heating element.

Abstract: A fixing device includes a heating element extending in a first direction and configured to generate heat, a nip member extending along the heating element in the first direction and configured to receive radiant heat from the heating element, an endless belt extending along the heating element in the first direction, a backup member extending along the heating element in the first direction, and an adhesive. The endless belt is configured to rotate. The endless belt surrounds the heating element and the nip member. The backup member nips the endless belt in cooperation with the nip member. The adhesive is disposed between the heating element and the nip member and fixes the heating element and the nip member relative to each other.

Abstract: A fixing device for thermally fixing a developing agent image to a sheet includes a tubular member, a nip plate, a heater, a reflection plate, and a backup member. The tubular member has an inner peripheral surface defining an internal space and an axis defining an axial direction. The nip plate is disposed in the internal space, and the inner peripheral surface is in sliding contact with the nip plate. A heater is disposed in the internal space and confronts the nip plate in a confronting direction. The reflection plate is configured to reflect radiant heat from the heater toward the nip plate. A backup member is configured to provide a nip region in cooperation with the nip plate for nipping the fusing member between the backup member and the nip plate.

Abstract: A fixing device for thermally fixing a developing agent image to a sheet fed in a sheet feeding direction includes a tubular flexible fusing member, a nip plate, a heater, a reflection plate, and a backup member. The tubular flexible fusing member has an inner peripheral surface defining an internal space and an axis defining an axial direction. The nip plate is disposed in the internal space, and the inner peripheral surface is in sliding contact with the nip plate. A heater is disposed in the internal space and confronts the nip plate in a confronting direction. The reflection plate is configured to reflect a radiant heat from the heater toward the nip plate. A backup member is configured to provide a nip region in cooperation with the nip plate for nipping the fusing member between the backup member and the nip plate.

Abstract: A fixing device including: a flexible cylindrical member; a heater that is disposed inside the cylindrical member; a nip plate configured to be in contact with an inner peripheral surface of the cylindrical member and is configured to be heated by the heater; and a roller configured to pinch the cylindrical member between the roller and the nip plate, wherein, at least during fixing, the nip plate has a curved shape where a central portion thereof in an axial direction of the cylindrical member is more spaced from the roller than both end portions thereof in the axial direction, and wherein the roller is a concave roller where a diameter of a central portion thereof in the axial direction is smaller than diameters of both end portions thereof respectively.

Abstract: A fixing device for thermally fixing a developing agent image to a sheet includes: a flexible tubular member having an inner peripheral surface and circularly moving in a moving direction while the developing agent image is thermally fixed; a heater; a nip member being in sliding contact with the tubular member; a backup member nipping the tubular member in cooperation with the nip member; a stay covering the heater and supporting the nip member; an electric component positioned opposite to the heater with respect to the stay; and a frame supporting the electric component. The frame includes: an isolating portion interposed between the tubular member and the electric component for isolating the electric component from the tubular member; and a guide portion guiding the inner peripheral surface of the tubular member while the flexible tubular member is moving in the moving direction.

Abstract: A fixing device for thermally fixing a developing agent image to a sheet includes: a flexible tubular member having an inner peripheral surface defining an internal space; a heater; a nip member being in sliding contact with the inner peripheral surface of the flexible tubular member and having an electrically conductive surface; a stay supporting the nip member and being electrically conductive and electrically connected to the electrically conductive surface; a backup member nipping the flexible tubular member in cooperation with the nip member; a supporting member supporting the nip member and the stay, the supporting member being movable relative to the backup member; and a first grounding member disposed to be in contact with the stay for grounding the stay, the first grounding member being supported to the supporting member such that the first grounding member is integrally movable with the supporting member.

Abstract: A fixing device includes: a first fixing member and a second fixing member forming a nip portion for heat-fixing a recording sheet; an urging mechanism including an urging member and urging the first fixing member toward the second fixing member by an urging force of the urging member; a first frame for supporting the second fixing member; a second frame arranged at an opposite side to the second fixing member with the first fixing member being interposed therebetween; and a switching member, which applies a pressing force resisting the urging force to the first fixing member for switching a width of the nip portion, and which includes a cam to which the urging force is applied and a shaft for supporting the cam. The first frame and the second frame are connected to each other by the shaft.

Abstract: An image forming apparatus includes: a fixing device: having a heating member, a rotating member, and a temperature sensor; a sheet feeding unit; and a control device configured to perform a sheet feed control: in which the feeding timing is set to a first timing if the temperature gradient of the heating member for a predetermined period is larger than a first threshold value; and in which the feeding timing is set to a second timing later than the first timing if the temperature gradient of the heating member for the predetermined period is equal to or less than the first threshold value, and wherein, in the sheet feed control, the control device changes the first threshold value to a smaller value as the temperature of the heating member at the print-instruction receiving time increase.

Abstract: A fixing device for thermally fixing a developing agent image to a sheet includes a tubular member, a nip plate, a heater, a reflection plate, and a backup member. The tubular member has an inner peripheral surface defining an internal space and an axis defining an axial direction. The nip plate is disposed in the internal space, and the inner peripheral surface is in sliding contact with the nip plate. A heater is disposed in the internal space and confronts the nip plate in a confronting direction. The reflection plate is configured to reflect radiant heat from the heater toward the nip plate. A backup member is configured to provide a nip region in cooperation with the nip plate for nipping the fusing member between the backup member and the nip plate.

Abstract: A fuser unit includes: a cylindrical member; a heat generation member; a nip plate; a backup member that forms a nip portion; and a temperature detection member that detects a temperature of the nip plate. The nip plate has: a plate-shaped part that forms the nip portion; a lubricant restraint part that is formed on at least a part of a downstream side end of the plate-shaped part in a predetermined direction and that extends toward an inner side in a diametrical direction of the cylindrical member, and a detected part that extends from an end of the lubricant restraint part toward the predetermined direction. The detected part is formed to be shorter than the plate-shaped part in an axial direction of the cylindrical member, and both ends of the detected part in the axial direction are adjacent to a space.