An example image forming apparatus includes a toner cartridge, a photoconductive cartridge including a photosensitive drum, a development cartridge including a toner inlet portion and rotatable between a first position at which a developing roller is close to the photosensitive drum and a second position at which the developing roller is apart from the photosensitive drum, with respect to a hinge axis that is parallel to an axial direction of the developing roller and between the developing roller and the toner inlet portion, a buffer unit including a toner discharge portion to receive toner from the toner cartridge and to supply the toner to the development cartridge, and a toner supply duct connecting the toner discharge portion to the toner inlet portion, the toner supply duct being rotatably connected to the toner discharge portion in a direction allowing rotation of the development cartridge between the first and the second position.

When a sheet jam is detected, a processor may perform the following process. In a case where a sheet is spanning a first conveyance path and a drawer unit, the processor maintains a lock unit in a locked state by supplying power to the lock unit via the drawer unit from a power supply without depending on whether a door is in an open state or a closed state. In a case where a sheet is not spanning the first conveyance path and the drawer unit, the processor controls supplying and disconnecting of power to the drawer unit from the power supply in accordance with whether the door is in a closed state or an open state.

In a case where a cleaning member is located at a cleaning position in attachment of a process cartridge to an image forming apparatus, a stopper located at a first position butts against the process cartridge guided in a direction of attachment by a guide portion such that the process cartridge is disabled from being attached to the image forming apparatus, and in a case where the cleaning member is located at a retraction position in attachment of the process cartridge to the image forming apparatus, a lever portion moves due to a press by a cleaning unit and the stopper moves from the first position to a second position such that the process cartridge is enabled to be attached to the image forming apparatus.

An image forming apparatus includes a photosensitive member, a developing roller, first and second motors, a drive-train having a drive switching unit, and a development switching unit. The drive-train transmits a driving force of the first motor to the developing roller. The second motor drives the drive switching unit and the development switching. The drive switching unit switches between a driving force transmission state and a driving force non-transmission state. The development switching unit switches between a developing roller-photosensitive member contact state and a developing roller-photosensitive member separated state, and operates with an operation of the drive switching unit. When the drive switching unit transitions from the non-transmission to the transmission state and a detected magnitude of a current flowing through the first motor has changed, the second motor is stopped before the developing roller is brought into contact with the photosensitive member while driving the first motor.

An image-forming device includes a main casing, a belt accommodated in the main casing, developing units arranged along the belt, a drawer configured to detachably support the developing units, the drawer configured to move to a position inside the main casing and to a position outside the main casing, and the drawer having a leading end and a trailing end in a pulling direction from the inside position to the outside position; and a guide configured to guide the drawer and to move between a first position and a second position when the drawer is at the inside position, the second position being farther from the belt than the first position from the belt. When the guide is at the second position, the guide is configured to be tilted downward relative to a horizontal direction such that the leading end is lower than the trailing end.

An image forming apparatus includes a drum unit, a process frame, a lock member and an intermediate transferring unit. The drum unit rotatably supports a rotating shaft of a photosensitive drum. The process frame has an attachment part to which the drum unit is attached. The lock member positions the drum unit to the attachment part. The intermediate transferring unit is attached to the process frame after the drum unit is attached. The lock member has a supporting part, an engagement part and a restriction part. Though the supporting part, an end of the rotating shaft is passed. The engagement part is engaged with the process frame between the process frame and the intermediate transferring unit. The restriction part interferes with the intermediate transferring unit between the engagement part and the intermediate transferring unit to prevent the engagement part from being detached from the process frame.

A sheet processing apparatus has a main body with an insertion slot for a sheet cassette. The sheet cassette has a moveable pin member. A housing in the main body includes a lever partially rotatable about a first axis. The lever has a pin engagement portion at an end of the lever that rotates about a second axis and has an engagement groove into which the pin member can be inserted from a first pin engagement position and a second pin engagement position when the lever has rotated about the first axis. An elastic member applies a force to the lever to rotate the lever toward the insertion direction of the cassette. The housing includes a chassis having a guide groove extending along the insertion direction. The guide groove includes an inclining portion that is inclined with respect to the insertion direction.

A cartridge includes a photosensitive member, a charging member configured to charge the photosensitive member, a first unit including the photosensitive member and the charging member, a developing member configured to deposit toner onto the photosensitive member, and a second unit including the developing member. A holding portion is movably supported by the first unit or the second unit, with the holding portion being configured to restrict a relative position between the first unit and the second unit, the holding portion being movable between a first position for holding the second unit in a spaced position by the first unit and a second position for holding the second unit in a developing position by the first unit. An urging portion including a force receiving portion capable of receiving an external force, with the urging portion being capable of applying, to the second unit, an urging force for urging the second unit toward the developing position while receiving the external force at the force receiving portion.

A sheet processing apparatus has a main body with an insertion slot for a sheet cassette. The sheet cassette has a moveable pin member. A housing in the main body includes a lever partially rotatable about a first axis. The lever has a pin engagement portion at an end of the lever that rotates about a second axis and has an engagement groove into which the pin member can be inserted from a first pin engagement position and a second pin engagement position when the lever has rotated about the first axis. An elastic member applies a force to the lever to rotate the lever toward the insertion direction of the cassette. The housing includes a chassis having a guide groove extending along the insertion direction. The guide groove includes an inclining portion that is inclined with respect to the insertion direction.

An image forming apparatus includes an imaging unit attachable/detachable at a predetermined position of an apparatus body. The imaging unit includes a locking member and a cover member. The locking member is configured so as to move between a lock position engaging with the apparatus body when the imaging unit is attached to the predetermined position and a lock release position releasing engaging with the apparatus body. The cover member is attached to/detached from the imaging unit in a first direction. The cover member has a connecting part making possible to be attached to the imaging unit in a second direction. When the cover member is attached to the imaging unit in the second direction, the connecting part moves the locking member from the lock position to the lock release position and the imaging unit becomes a state capable of being detached from the predetermined position.