A rotating force transmitting part for an electrophotographic photosensitive drum for a main assembly of the electrophotographic image forming apparatus, wherein the main assembly of the electrophotographic image forming apparatus includes a driving shaft, to be driven by a motor, having the rotating force applying portion, and wherein the electrophotographic photosensitive drum is dismountable from the main assembly of the electrophotographic image forming apparatus in a direction substantial perpendicular with an axial direction of the driving shaft, the rotating force transmitting part includes a coupling member engageable with the rotational force applying portion to receive a rotational force for rotating the electrophotographic photosensitive drum in the state in which electrophotographic photosensitive drum is mounted to the main assembly of the electrophotographic image forming apparatus, wherein the coupling member being capable of taking a rotational force transmitting angular position for transmitting the rotational force for rotating the electrophotographic photosensitive drum to the electrophotographic photosensitive drum and a disengaging angular position in which the coupling member is inclined away from the axis of the electrophotographic photosensitive drum from the rotational force transmitting angular position, wherein when the process cartridge is dismounted from the main assembly of the electrophotographic image forming apparatus in a direction substantially perpendicular to the axis of the electrophotographic photosensitive drum, the coupling member moves from the rotational force transmitting angular position to the disengaging angular position.

A developing cartridge includes a frame rotatably supporting a developing roller. The developing cartridge also includes a first supporting member attached to a first end of the frame, with the first supporting member being movable relative to the frame. The developing cartridge further includes a second supporting member attached to a second end of the frame, with the second supporting member being movable relative to the frame and the first supporting member.

The present invention provides a cartridge which is dismountable from the main assembly without deteriorating usability performance in a predetermined direction substantially perpendicular to the rotational axis of an image bearing member, the main assembly being not provided with the mechanism for moving the main assembly side engaging portion in the rotational axis direction in response to the opening and closing operation of the main assembly cover of the main assembly.

With the movement of the cartridge in such a direction perpendicular to the rotational axis of the image bearing member in the dismounting of the cartridge from the main assembly of the electrophotographic image forming apparatus, the coupling member movable in a direction parallel with the rotational axis of the image bearing member enters a inside of a recess of the main assembly side engaging portion provided in the main assembly of the apparatus to receive a rotational force from the main assembly side engaging portion.

An image forming apparatus includes: a reconveying unit including a reconveying roller; and a second transmission mechanism. The second transmission mechanism transmits a drive force to the reconveying roller and includes: an input gear; an output gear; an intermediate gear including first and second gears; and first and second swinging gears. The first toothless part of the first gear and the second toothless part of the second gear are provided at such a position that, when the intermediate gear is rotated by a drive force transmitted from the input gear through the second swinging gear while the second swinging gear meshes with the second toothed part of the second gear and the output gear meshes with the first toothed part of the first gear, the first toothless part reaches a position confronting the output gear and then the second toothless part reaches a position confronting the second swinging gear.

An image forming apparatus is configured such that in a case where images are to be formed on a first surface of a preceding sheet, on a first surface of a succeeding sheet fed to the first conveyance path succeeding to the preceding sheet and on a second surface of the preceding sheet, a first conveyance member is stopped without reversing the preceding sheet to a second conveyance path in a case where the image has been formed on the first surface of the preceding sheet and permission of preparing the image to be formed on the first surface of the succeeding sheet is not issued yet. The first conveyance member restarts conveyance of the preceding sheet to the second conveyance path based on timing when an image forming unit starts preparing the image to be formed on the first surface of the succeeding sheet.

In a drive mechanism, a two-stage gear has an input gear and a sun gear. A planetary gear is engaged with both of outer teeth of the sun gear and inner teeth of a ring gear. A carrier, which is capable of rotating together with a rotational shaft, supports the planetary gear, and outputs drive force. A drive force transmission switching member switches between a connecting state connecting the two-stage gear and the carrier such that they rotate together via the rotational shaft, and a separating state separating the two-stage gear and carrier such that they rotate relative to each other. A one-way clutch allows the ring gear to rotate in one of a pair of opposite directions about the central axis of the rotational shaft, and prohibits the ring gear from rotating in the other one of the pair of opposite directions.

In a developing cartridge, a developing roller extends in a first direction. A developing roller gear, a coupling, and first and second idle gears are positioned at an outer surface of a casing. An agitator gear has an end face in the first direction facing the outer surface. A first protrusion is positioned between the end face and the outer surface, and at a position outside of addendum circles of the developing roller gear, coupling, and first and second idle gears. The first protrusion is pivotally movable about an axis extending in the first direction between a first position and a second position. The first protruding portion has, at the first position, a first length in a second direction connecting the developing roller and the first protruding portion, and has, at the second position, a second length different from the first length in the second direction.

A flywheel includes a rotation shaft, a flywheel body, and a protruding body. A first end of the rotation shaft is supported by a rotating body. The flywheel body is provided at a second end of the rotation shaft and rotates together with the rotation shaft. The protruding body protrudes from a surface at a rotating-body side of the flywheel body and extends in a circumferential direction of the rotation shaft.

An image forming apparatus includes a housing and a drum unit. The drum unit is out of the housing at a first position, moved in a first direction from the first position to a second position in the housing, and then to a third position away from the first position. The drum unit includes: a photosensitive drum; a cleaning unit for toner; a conveying tube extending in the first direction; a conveying member in the conveying tube and rotatable about a first axis extending in the first direction; and a first gear fixed to the conveying member and rotatable about the first axis. The housing has a second gear rotatable about a second axis extending in the first direction. The first gear is separated from the second gear at the second position, and engaged with the second gear at the third position. The first axis and the second axis overlap in the third position.

Disclosed in the present invention is a developing cartridge, which is detachably mounted in an image forming device, comprising: a housing; a developing roller rotatably supported by the housing, the developing roller rotating about an axis extending in a first direction; a supply roller rotatably supported by the housing and configured to convey a developer to the developing roller, the supply roller having a supply roller shaft made of metal; a driving gear disposed on a driving side of the housing in the first direction; and an electrode electrically connected to the developing roller shaft, comprising a first part, a second part, and an intermediate electrical connection part connecting the first part and the second part; wherein the first part is located on an opposite side of the driving side of the housing, the second part is located on the driving side of the housing, and the opposite side of the driving side and the driving side are opposite ends of the housing in the first direction; and the second part is simultaneously in contact with the supply roller shaft and the developing roller shaft.