Abstract: An image forming apparatus includes a cartridge including a developing member mountable in and dismountable from a main assembly in a direction crossing a rotational axis direction of the developing member. A grip portion of the cartridge extends in a direction along a dismounting direction of the cartridge from the main assembly in a state in which the cartridge is mounted in the main assembly. An openable member in the main assembly includes a guiding portion to support the cartridge from below and guide the cartridge while the cartridge is being dismounted from the main assembly, with the guiding portion including a guiding surface having a downwardly recessed shape on a cross-section perpendicular to the rotational axis direction and guiding the cartridge so that an extending direction of the grip portion approaches a vertical direction as the cartridge is moved in the dismounting direction.

Abstract: An image forming apparatus includes a photosensitive member, a cartridge, a main assembly including an opening and an openable member. The grip portion extends from a frame of the cartridge along a cartridge dismounting direction. The openable member includes a guiding portion for guiding the cartridge when the openable member is in an open position and the cartridge is dismounted from the main assembly. The guiding portion includes a guiding surface for guiding the frame of the cartridge so that an extending direction of the grip portion approaches a vertical direction with movement of the cartridge in the cartridge dismounting direction.

Abstract: An image forming apparatus includes a supporting member configured to support a developing unit and be movable between a first position and a second position, an opening/closing member configured to open and close an opening through which the developing unit passes when the developing unit is attached to or detached from the supporting member, and a restriction member configured to restrict a movement of the supporting member from a third position different from the first and second positions, wherein in case where the opening/closing member is opened when the supporting member is at the first position, the restriction member presses the supporting member to move to the third position, and in case where the opening/closing member is opened when the supporting member is at the second position, the restriction member presses the supporting member to move to the third position.

Abstract: An image forming apparatus includes a supporting member configured to support a developing unit and be movable between a first position and a second position, an opening/closing member configured to open and close an opening through which the developing unit passes when the developing unit is attached to or detached from the supporting member, and a restriction member configured to restrict a movement of the supporting member from a third position different from the first and second positions, wherein in case where the opening/closing member is opened when the supporting member is at the first position, the restriction member presses the supporting member to move to the third position, and in case where the opening/closing member is opened when the supporting member is at the second position, the restriction member presses the supporting member to move to the third position.

Abstract: An object is to provide an image forming apparatus capable of switching, with a simple configuration, the positional relation between a supporting member and a feeding member and the positional relation between a developing member and a photosensitive member. A separation cam 100 rotated by the driving force of a motor M and a slider 101 moving in accordance with the rotation of the separation cam 100 are configured to switch the positional relation between a lifting plate 13 and a feeding roller 3 and the positional relation between a developing roller 103b and a photosensitive drum 8.

Abstract: In order to enable a main body of an image forming apparatus to selectively attach and detach a first cartridge group and a second cartridge group, a first guide for positioning the first cartridge group to the main body of the image forming apparatus and a second guide for positioning the second cartridge group to the main body of the image forming apparatus are detachably attachable to the main body of the image forming apparatus.

Abstract: An object is to provide an image forming apparatus capable of switching, with a simple configuration, the positional relation between a supporting member and a feeding member and the positional relation between a developing member and a photosensitive member. A separation cam 100 rotated by the driving force of a motor M and a slider 101 moving in accordance with the rotation of the separation cam 100 are configured to switch the positional relation between a lifting plate 13 and a feeding roller 3 and the positional relation between a developing roller 103b and a photosensitive drum 8.

Abstract: In order to enable a main body of an image forming apparatus to selectively attach and detach a first cartridge group and a second cartridge group, a first guide for positioning the first cartridge group to the main body of the image forming apparatus and a second guide for positioning the second cartridge group to the main body of the image forming apparatus are detachably attachable to the main body of the image forming apparatus.

Abstract: The sheet feeding apparatus includes a feeding roller that includes an arc-shaped friction portion and a notch portion, and causes the friction portion to feed the sheet; a feeding motor rotationally driving the feeding roller; a separation pad that presses the sheet fed by the friction portion on a surface other than a surface at the friction portion, and separates a double-fed sheet; and a feeding spring that causes the sheet supporting portion to wait below the feeding roller such that the sheet supported on the sheet supporting portion is not in contact with the friction portion until the friction portion reaches the separation pad, and, when the friction portion reaches the separation pad, moves up the sheet supporting portion to an abutting position at which the sheet supported on the sheet supporting portion is pressed against the friction portion and the friction portion feeds the sheet.

Abstract: A reversely-rotatable roller conveys a sheet having an image formed on its one side at a sheet conveying velocity faster than that of a conveying roller by normal rotation and then, the reversely-rotatable roller conveys the sheet to a re-conveying path by reverse rotation. The sheet conveying velocity of the reversely-rotatable roller when the reversely-rotatable roller reversely rotates is made slower than the sheet conveying velocity when the reversely-rotatable roller normally rotates so that the sheet conveying velocity of the re-conveying roller is substantially equal to or slower than the sheet conveying velocity of the conveying roller.

Abstract: A link member is rotatably supported by a lifting plate. When the lifting plate moves upward and downward, the movement of the link member is guided by a guide portion provided on a link guide hole. Before sheet feeding starts, the movement of the link member is regulated by a holding portion provided on a lower end of the guide portion so as to hold the lifting plate in a standby position against a biasing force of a feed spring. When the sheet is fed, a feed cam rotating integrally with a feed roller presses the link member to release the link member from being locked by the holding portion of the link guide hole to thereby make the link member movable along the guide portion.

Abstract: The present invention provides a sheet feeding apparatus including a sheet stacking portion, a feeding roller, a biasing member, and a cam member, wherein a predetermined idling section in which the feeding roller does not work with rotation of the feeding shaft is provided between the feeding roller and the feeding shaft, the sheet feeding apparatus comprises a returning mechanism which returns the feeding roller to the initial feeding position after the feeding roller finishes feeding the sheet on the sheet stacking portion, and when a sheet feeding operation is started, at a time when the cam member starts rotating together with the feeding shaft and passes the idling section, the feeding roller starts rotating, feeds out the sheet on the sheet stacking portion and then is returned to the initial feeding position by the returning mechanism.

Abstract: At a start of sheet feeding operation, a feed cam starts to rotate in association with rotation of a feed shaft and a feed roller starts to rotate from a time when the feed shaft has passed an idle zone, so as to send out each of sheets on a rising and lowering plate. After that, the feed roller is returned to a feed initial position by a return mechanism including a conveyance roller and a feed rotatable member. A cam curve of the feed cam reduces a rising speed as compared to a rising speed of a conventional rising and lowering plate, and reduces generation of noise at the time of collision between the sheets on the rising and lowering plate and the feed rotatable member. Thus, an image forming apparatus having lower noise level can be provided.

Abstract: The sheet feeding apparatus includes a feeding roller that includes an arc-shaped friction portion and a notch portion, and causes the friction portion to feed the sheet; a feeding motor rotationally driving the feeding roller; a separation pad that presses the sheet fed by the friction portion on a surface other than a surface at the friction portion, and separates a double-fed sheet; and a feeding spring that causes the sheet supporting portion to wait below the feeding roller such that the sheet supported on the sheet supporting portion is not in contact with the friction portion until the friction portion reaches the separation pad, and, when the friction portion reaches the separation pad, moves up the sheet supporting portion to an abutting position at which the sheet supported on the sheet supporting portion is pressed against the friction portion and the friction portion feeds the sheet.

Abstract: A link member is rotatably supported by a lifting plate. When the lifting plate moves upward and downward, the movement of the link member is guided by a guide portion provided on a link guide hole. Before sheet feeding starts, the movement of the link member is regulated by a holding portion provided on a lower end of the guide portion so as to hold the lifting plate in a standby position against a biasing force of a feed spring. When the sheet is fed, a feed cam rotating integrally with a feed roller presses the link member to release the link member from being locked by the holding portion of the link guide hole to thereby make the link member movable along the guide portion.

Abstract: At a start of sheet feeding operation, a feed cam starts to rotate in association with rotation of a feed shaft and a feed roller starts to rotate from a time when the feed shaft has passed an idle zone, so as to send out each of sheets on a rising and lowering plate. After that, the feed roller is returned to a feed initial position by a return mechanism including a conveyance roller and a feed rotatable member. A cam curve of the feed cam reduces a rising speed as compared to a rising speed of a conventional rising and lowering plate, and reduces generation of noise at the time of collision between the sheets on the rising and lowering plate and the feed rotatable member. Thus, an image forming apparatus having lower noise level can be provided.

Abstract: The present invention provides a sheet feeding apparatus including a sheet stacking portion, a feeding roller, a biasing member, and a cam member, wherein a predetermined idling section in which the feeding roller does not work with rotation of the feeding shaft is provided between the feeding roller and the feeding shaft, the sheet feeding apparatus comprises a returning mechanism which returns the feeding roller to the initial feeding position after the feeding roller finishes feeding the sheet on the sheet stacking portion, and when a sheet feeding operation is started, at a time when the cam member starts rotating together with the feeding shaft and passes the idling section, the feeding roller starts rotating, feeds out the sheet on the sheet stacking portion and then is returned to the initial feeding position by the returning mechanism.

Abstract: A reversely-rotatable roller conveys a sheet having an image formed on its one side at a sheet conveying velocity faster than that of a conveying roller by normal rotation and then, the reversely-rotatable roller conveys the sheet to a re-conveying path by reverse rotation. The sheet conveying velocity of the reversely-rotatable roller when the reversely-rotatable roller reversely rotates is made slower than the sheet conveying velocity when the reversely-rotatable roller normally rotates so that the sheet conveying velocity of the re-conveying roller is substantially equal to or slower than the sheet conveying velocity of the conveying roller.