Abstract: A sheet feeding device includes a door movable between an opened position and a closed position relative to an apparatus body, a stacking portion for a sheet, a cover portion configured to be situated at a first position when the door is situated at the opened position and to be situated at a second position when the door is situated at the closed position, and a moving unit including a feeding roller and a moving member supporting the feeding roller. The moving member is movable with respect to the stacking portion in a first direction in which the feeding roller comes close to the stacking portion and in a second direction which is opposite to the first direction. In a state in which the cover portion is situated at the first position, the moving unit is situated between the cover portion and the door.

Abstract: A sheet feeding apparatus includes a sheet supporting portion configured to support a first sheet and a second sheet that are superposed in a stacking direction, a rotary feeding member, a separation portion, a return portion configured to return the second sheet, separated by the separation portion from the first sheet, toward the sheet supporting portion, and a regulating portion comprising a regulating surface, the regulating portion being configured to move between a regulating position configured to regulate the position of leading edges of the first sheet and the second sheet by the regulating surface, and an allowing position being configured to allow feeding of the first sheet and the second sheet supported on the sheet supporting portion, the regulating surface being extended in the stacking direction in a state where the regulating portion is positioned at the regulating position.

Abstract: A sheet feeding apparatus includes a stacking portion having a stacking surface on which sheets are stacked, a feeding portion configured to feed the sheets stacked on the stacking surface, and an abutment member having a contact surface configured to contact edges of the sheets stacked on the stacking surface and extending along a stacking direction of the sheets. The abutment member moves with a constant contact angle between the contact surface and the edges of the sheets in a cross section parallel with the stacking direction in a case where the contact surface is pushed by the sheets inserted toward the feeding portion in an insertion direction. In addition, a detection portion is configured to output a detection signal in accordance with a position of the abutment member.

Abstract: A sheet feeding device includes a sheet stacking unit to stack a plurality of sheets, a feeding unit to feed sheets stacked on the sheet stacking unit, a separation unit, and a moving unit provided with at least a first moving member and a second moving member. The separation unit contacts the sheets fed by the feeding unit and separates a sheet from the sheets. The moving unit contacts the first and the second moving members to move a sheet contacting the first and the second moving members to an upstream side in a feeding direction. A leading edge of the sheet is positioned between the separation unit and the feeding unit. When pressed by the sheet, the first and the second moving members are configured to thrust-move independently of each other.

Abstract: A sheet feeding device includes a sheet stacking unit to stack a plurality of sheets, a feeding unit to feed sheets stacked on the sheet stacking unit, a separation unit, and a moving unit provided with at least a first moving member and a second moving member. The separation unit contacts the sheets fed by the feeding unit and separates a sheet from the sheets. The moving unit contacts the first and the second moving members to move a sheet contacting the first and the second moving members to an upstream side in a feeding direction. A leading edge of the sheet is positioned between the separation unit and the feeding unit. When pressed by the sheet, the first and the second moving members are configured to thrust-move independently of each other.

Abstract: A sheet feeding apparatus includes a stacking portion comprising a stacking surface on which sheets are stacked, a feeding portion configured to feed the sheets stacked on the stacking surface, an abutment member comprising a contact surface configured to contact edges of the sheets stacked on the stacking surface and extending along a stacking direction of the sheets, the abutment member being configured to move with a constant contact angle between the contact surface and the edges of the sheets in a cross section parallel with the stacking direction in a case where the contact surface is pushed by the sheets stacked on the stacking surface, and a detection portion configured to output a detection signal in accordance with a position of the abutment member.

Abstract: A fixing device includes a cylindrical film, a planar heater, a heat conduction member, a supporting member, a limiting member for limiting heater end portions with respect to a generatrix direction of the film so as to prevent the end portions from moving in a heater thickness direction relative to the supporting member, and a pressing member. A fixing device state is switchable between a first state in which a press-contact force in the nip is enough to fix the toner image and a second state in which the press-contact force in the nip is smaller than the press-contact force in the first state. A surface where the supporting member opposes the heat conduction member has a shape such that with respect to the generatrix direction, a central portion of the film is projected toward the pressing member to a greater extent than an end portion of the film.

Abstract: A fixing device includes a cylindrical film, a planar heater, a heat conduction member, a supporting member, a limiting member for limiting heater end portions with respect to a generatrix direction of the film so as to prevent the end portions from moving in a heater thickness direction relative to the supporting member, and a pressing member. A fixing device state is switchable between a first state in which a press-contact force in the nip is enough to fix the toner image and a second state in which the press-contact force in the nip is smaller than the press-contact force in the first state. A surface where the supporting member opposes the heat conduction member has a shape such that with respect to the generatrix direction, a central portion of the film is projected toward the pressing member to a greater extent than an end portion of the film.

Abstract: In a fixing device according to an exemplary embodiment of the present invention, a projection portion projected in a direction opposite to a direction biased by the biasing member, from a body part of the biasing member, is provided in a biasing member configured to push a thermosensitive member which receives heat from a heater, toward the heater, so that a crack in the heater at the time of an abnormal temperature rise is prevented.

Abstract: A fixing device includes a cylindrical film, a planar heater, a heat conduction member, a supporting member, a limiting member for limiting heater end portions with respect to a generatrix direction of the film so as to prevent the end portions from moving in a heater thickness direction relative to the supporting member, and a pressing member. A fixing device state is switchable between a first state in which a press-contact force in the nip is enough to fix the toner image and a second state in which the press-contact force in the nip is smaller than the press-contact force in the first state. A surface where the supporting member opposes the heat conduction member has a shape such that with respect to the generatrix direction, a central portion of the film is projected toward the pressing member to a greater extent than an end portion of the film.

Abstract: An image forming apparatus according to the present invention can switch a fixing nip portion between a pressurized state and a pressure released state by rotating a cam via a first engagement portion provided in a fixing unit, and a second engagement portion provided in a main body of the image forming apparatus, in which a difference between a phase of the cam in the pressurized state and a phase of the cam in the pressure released state is 180°, and the first engagement portion and the second engagement portion engage with each other when the fixing unit is mounted on the main body regardless of whether the fixing nip portion is in the pressurized state or the pressure released state.

Abstract: In a fixing device according to an exemplary embodiment of the present invention, a projection portion projected in a direction opposite to a direction biased by the biasing member, from a body part of the biasing member, is provided in a biasing member configured to push a thermosensitive member which receives heat from a heater, toward the heater, so that a crack in the heater at the time of an abnormal temperature rise is prevented.

Abstract: An image forming apparatus according to the present invention can switch a fixing nip portion between a pressurized state and a pressure released state by rotating a cam via a first engagement portion provided in a fixing unit, and a second engagement portion provided in a main body of the image forming apparatus, in which a difference between a phase of the cam in the pressurized state and a phase of the cam in the pressure released state is 180°, and the first engagement portion and the second engagement portion engage with each other when the fixing unit is mounted on the main body regardless of whether the fixing nip portion is in the pressurized state or the pressure released state.

Abstract: A fixing device includes a cylindrical film, a planar heater, a heat conduction member, a supporting member, a limiting member for limiting heater end portions with respect to a generatrix direction of the film so as to prevent the end portions from moving in a heater thickness direction relative to the supporting member, and a pressing member. A fixing device state is switchable between a first state in which a press-contact force in the nip is enough to fix the toner image and a second state in which the press-contact force in the nip is smaller than the press-contact force in the first state. A surface where the supporting member opposes the heat conduction member has a shape such that with respect to the generatrix direction, a central portion of the film is projected toward the pressing member than an end portion of the film.

Abstract: A fixing device for fixing a toner image formed on a sheet includes a cylindrical film; a heater having a first surface contacting an inner surface of the film; an opposed member forming a press-contact portion with the film therebetween; a supporting member for supporting a second surface of the heater opposite the first surface; and a heat conduction member contacting the second surface. In a generatrix direction of the film, an end portion of a contact region between the heat conduction member and the second surface is at or inside an end portion of the press-contact portion. In a region from an end portion of the contact region to an outside of an end portion of the press-contact portion with respect to the direction, the supporting member includes a first region not contacting the second surface and a second region contacting the second surface outside the first region.

Abstract: A fixing device includes a cylindrical film, a planar heater, a heat conduction member, a supporting member, a limiting member for limiting heater end portions with respect to a generatrix direction of the film so as to prevent the end portions from moving in a heater thickness direction relative to the supporting member, and a pressing member. A fixing device state is switchable between a first state in which a press-contact force in the nip is enough to fix the toner image and a second state in which the press-contact force in the nip is smaller than the press-contact force in the first state. A surface where the supporting member opposes the heat conduction member has a shape such that with respect to the generatrix direction, a central portion of the film is projected toward the pressing member to a greater extent than an end portion of the film.

Abstract: In an image forming apparatus, when the openable and closable member is closed, the regulating member is mounted to the main body of the apparatus in a second state that is elastically changed from a first state; when the openable and closable member is opened, the regulating member is elastically returned to the first state; in this state, when the openable and closable member is closed, an abutting portion of the openable and closable member abuts on an abutting portion of the regulating member to regulate the openable and closable member from closing. A direction of pressing caused when the abutting portion of the openable and closable member abuts on the abutting portion of the regulating member is different from a direction in which the abutting portion of the regulating member moves when the regulating member changes from the first state to the second state.

Abstract: A fixing device for fixing a toner image formed on a sheet includes a cylindrical film; a heater having a first surface contacting an inner surface of the film; an opposed member forming a press-contact portion with the film therebetween; a supporting member for supporting a second surface of the heater opposite the first surface; and a heat conduction member contacting the second surface, wherein in a generatrix direction of the film, an end portion of a contact region between the heat conduction member and the second surface is at or inside an end portion of the press-contact portion. In a region from an end portion of the contact region to an outside of an end portion of the press-contact portion with respect to the direction, the supporting member includes a first region not contacting the second surface and a second region contacting the second surface outside the first region.

Abstract: A fixing device includes a cylindrical film, a planar heater, a heat conduction member, a supporting member, a limiting member for limiting heater end portions with respect to a generatrix direction of the film so as to prevent the end portions from moving in a heater thickness direction relative to the supporting member, and a pressing member. A fixing device state is switchable between a first state in which a press-contact force in the nip is enough to fix the toner image and a second state in which the press-contact force in the nip is smaller than the press-contact force in the first state. A surface where the supporting member opposes the heat conduction member has a shape such that with respect to the generatrix direction, a central portion of the film is projected toward the pressing member than an end portion of the film.

Abstract: An image forming apparatus includes an image bearing member on which an electrostatic image is to be formed; a rotatable supporting member, configured to support a developing device for developing the electrostatic image and configured to rotationally move the developing device toward a developing position, provided movably in a rotational axis direction with respect to a main assembly of the image forming apparatus; an urging member for urging the rotatable supporting member in the rotational axis direction. In addition, a regulating portion regulates a position of the rotatable supporting member, with respect to the rotational axis direction, urged by the urging member.