Abstract: A developing roller is located nearer a first end than a second end in a first direction. A first boss extends in a second direction and is movable together with a housing. The first boss bears the weight of a developer cartridge when the first boss is supported by a support surface of a first side plate of a drum unit, and is located away from the developing roller in the first direction and the third direction. A first pressure receiving surface is located farther away from the developing roller than the first boss in the third direction. The pressure receiving member receives a pressing force in the third direction from a pressing member of the first side plate of the drum unit. The first boss is located away from the developing roller in the first direction by a first distance. The first pressure receiving surface is located away from the developing roller in the first direction by the first distance or by a second distance smaller than the first distance.

Abstract: A developing cartridge includes: a casing; a developing roller; a shaft; and a cam. The casing is configured to accommodate developer therein. The developing roller is rotatable about a first axis extending in an axial direction. The shaft extends along a second axis extending in the axial direction. The shaft is movable along the second axis. The cam is movable along the second axis in response to axial movement of the shaft. The cam has a cam surface non-parallel with the second axis.

Abstract: A photosensitive drum is rotatable about a drum axis extending in a first direction. A frame includes a first side plate located at first end in the first direction and a second side plate spaced from the first side plate in the first direction. The frame rotatably supports the photosensitive drum between the first side plate and the second side plate in the first direction. The frame holds a developer cartridge. A lock lever is pivotable about a pivot axis extending in a second direction intersecting with the first direction. The lock lever is movable between a lock position at which the developer cartridge is locked on the frame and a release position at which the developer cartridge is unlocked from the frame.

Abstract: A developing cartridge includes: a casing; a developing roller; a shaft; and a cam. The casing is configured to accommodate developer therein. The developing roller is rotatable about a first axis extending in an axial direction. The shaft extends along a second axis extending in the axial direction. The shaft is movable along the second axis. The cam is movable along the second axis in response to axial movement of the shaft. The cam has a cam surface non-parallel with the second axis.

Abstract: A developing roller is located nearer a first end than a second end in a first direction. A first boss extends in a second direction and is movable together with a housing. The first boss bears the weight of a developer cartridge when the first boss is supported by a support surface of a first side plate of a drum unit, and is located away from the developing roller in the first direction and the third direction. A first pressure receiving surface is located farther away from the developing roller than the first boss in the third direction. The pressure receiving member receives a pressing force in the third direction from a pressing member of the first side plate of the drum unit. The first boss is located away from the developing roller in the first direction by a first distance. The first pressure receiving surface is located away from the developing roller in the first direction by the first distance or by a second distance smaller than the first distance.

Abstract: A developing cartridge includes: a casing, a developing roller, a first agitator, a supply roller, and a second agitator. The casing is configured to accommodate toner. The developing roller is rotatable about a developing roller rotation axis extending in a first direction. The first agitator is configured to agitate the toner. The first agitator is rotatable about a first agitator rotation axis extending in the first direction. The supply roller is positioned between the first agitator and the developing roller. The supply roller is rotatable about a supply roller rotation axis extending in the first direction. The second agitator is positioned between the supply roller and the first agitator. The second agitator is rotatable about a second agitator rotation axis extending in the first direction. A rotation locus of the second agitator is positioned outside of a rotation locus of the first agitator.

Abstract: A drawer includes: a photosensitive drum; and a frame to which a developing cartridge is attachable. The photosensitive drum is rotatable about a rotational axis extending in an axial direction. The photosensitive drum has an outer circumferential surface. The developing cartridge includes a developing roller having an outer circumferential surface. The developing cartridge is attachable to the frame in a state where the outer circumferential surface of the developing roller faces the outer circumferential surface of the photosensitive drum. The frame is configured to move the developing roller in a separation direction in response to movement in the axial direction of at least a portion of the developing cartridge attached to the frame. The separation direction is a direction in which the outer circumferential surface of the developing roller separates from the outer circumferential surface of the photosensitive drum.

Abstract: A developing cartridge includes a developing roller, a casing, and a cam. The developing roller is configured to be positioned at a contact position where the developing roller is in contact with a photosensitive drum of a drum cartridge. The developing roller is also configured to be positioned at a separated position where the developing roller is separated from the photosensitive drum. The cam is movable relative to the casing between a first position and a second position. A portion of the developing cartridge is in contact with the drum cartridge and functions as a pivot center so that the casing and the developing roller are pivotally moved about the pivot center when the cam is moved from the first position to the second position.

Abstract: A developing cartridge includes: a developing roller rotatable about a first axis extending in a first direction; a casing; a first shaft extending in the first direction and movable in the first direction between a first position and a second position; a first inclined surface movable together with the first shaft; a second shaft extending in the first direction and movable in the first direction between a third position and a fourth position; a second inclined surface movable together with the second shaft; and a link mechanism connecting the first shaft to the second shaft. The link mechanism shifts to a first state to move the second shaft to the third position when the first shaft is at the first position. The link mechanism shifts to a second state to move the second shaft to the fourth position when the first shaft is at the second position.

Abstract: A developing cartridge includes: a casing, a developing roller, a first agitator, a supply roller, and a second agitator. The casing is configured to accommodate toner. The developing roller is rotatable about a developing roller rotation axis extending in a first direction. The first agitator is configured to agitate the toner. The first agitator is rotatable about a first agitator rotation axis extending in the first direction. The supply roller is positioned between the first agitator and the developing roller. The supply roller is rotatable about a supply roller rotation axis extending in the first direction. The second agitator is positioned between the supply roller and the first agitator. The second agitator is rotatable about a second agitator rotation axis extending in the first direction. A rotation locus of the second agitator is positioned outside of a rotation locus of the first agitator.

Abstract: A cartridge includes: a housing; a storage medium; and a holder. The storage medium has an electrical contact surface. The holder is movable relative to the housing. The holder includes: a first holder member; and a second holder member. The first holder member has a pawl portion and is configured to hold the electrical contact surface. The second holder member includes a corner portion. The pawl portion is engageable with the corner portion. The second holder member has a through-hole. An engagement part of the pawl portion engaging with the corner portion is accessible from outside the second holder member through the through-hole in a state where the pawl portion engages with the corner portion.

Abstract: A developing cartridge includes a casing, a developing roller, a supply roller, a first agitator and a second agitator. The casing is configured to accommodate toner therein. The supply roller is configured to supply the toner to the developing roller. The first agitator is configured to agitate the toner in the casing. The second agitator is configured to agitate the toner in the casing. The second agitator is positioned between the first agitator and the supply roller. The second agitator includes a blade having a tip end configured to contact a peripheral surface of the supply roller.

Abstract: An image forming apparatus, having a casing, a cover, a first motor, a photosensitive drum, a second motor, a developing motor, a clutch, a contact/separation cam, a switching cam, and a controller, is provided. The controller conducts a first process, in which, when the cover is moved from an open position to a closed position, the controller drives the first motor to rotate the photosensitive drum without causing rotation of the developing roller; and a second process, in which, after a lapse of a first period since the controller started driving the first motor, the controller drives the second motor to move the contact/separation cam from the first phase to the second phase and move the switching cam from the first phase to the second phase causing the developing roller to be moved from the contacting position to the separated position while the photosensitive drum is rotating.

Abstract: A developing cartridge includes: a casing; a developing roller; a shaft; and a cam. The casing is configured to accommodate developer therein. The developing roller is rotatable about a first axis extending in an axial direction. The shaft extends along a second axis extending in the axial direction. The shaft is movable along the second axis. The cam is movable along the second axis in response to axial movement of the shaft. The cam has a cam surface non-parallel with the second axis.

Abstract: A developing roller is located nearer a first end than a second end in a first direction. A first boss extends in a second direction and is movable together with a housing. The first boss bears the weight of a developer cartridge when the first boss is supported by a support surface of a first side plate of a drum unit, and is located away from the developing roller in the first direction and the third direction. A first pressure receiving surface is located farther away from the developing roller than the first boss in the third direction. The pressure receiving member receives a pressing force in the third direction from a pressing member of the first side plate of the drum unit. The first boss is located away from the developing roller in the first direction by a first distance. The first pressure receiving surface is located away from the developing roller in the first direction by the first distance or by a second distance smaller than the first distance.

Abstract: A photosensitive drum is rotatable about a drum axis extending in a first direction. A frame includes a first side plate located at first end in the first direction and a second side plate spaced from the first side plate in the first direction. The frame rotatably supports the photosensitive drum between the first side plate and the second side plate in the first direction. The frame holds a developer cartridge. A lock lever is pivotable about a pivot axis extending in a second direction intersecting with the first direction. The lock lever is movable between a lock position at which the developer cartridge is locked on the frame and a release position at which the developer cartridge is unlocked from the frame.

Abstract: A developing cartridge includes: a casing, a developing roller, a first agitator, a supply roller, and a second agitator. The casing is configured to accommodate toner. The developing roller is rotatable about a developing roller rotation axis extending in a first direction. The first agitator is configured to agitate the toner. The first agitator is rotatable about a first agitator rotation axis extending in the first direction. The supply roller is positioned between the first agitator and the developing roller. The supply roller is rotatable about a supply roller rotation axis extending in the first direction. The second agitator is positioned between the supply roller and the first agitator. The second agitator is rotatable about a second agitator rotation axis extending in the first direction. A rotation locus of the second agitator is positioned outside of a rotation locus of the first agitator.

Abstract: A developing cartridge includes a casing having an outer surface, a developing roller, a first electrode, and a boss. The developing roller is movable together with the casing and includes a developing roller shaft extending along a first axis extending in a first direction. The developing roller is rotatable about the first axis. The first electrode is positioned at one end portion in the first direction of the developing roller shaft, and electrically connected to the developing roller shaft. The boss is positioned at one end portion in the first direction of the outer surface. The boss extends in the first direction and is engageable with the drum unit. A part of the first electrode is configured to contact with a second electrode of the drum unit as a result of pivotal movement of the developing cartridge about the boss relative to the drum unit.

Abstract: A developing cartridge includes: a casing; a developing roller; a shaft; and a cam. The casing is configured to accommodate developer therein. The developing roller is rotatable about a first axis extending in an axial direction. The shaft extends along a second axis extending in the axial direction. The shaft is movable along the second axis. The cam is movable along the second axis in response to axial movement of the shaft. The cam has a cam surface non-parallel with the second axis.

Abstract: A photosensitive drum is rotatable about a drum axis extending in a first direction. A frame includes a first side plate located at first end in the first direction and a second side plate spaced from the first side plate in the first direction. The frame rotatably supports the photosensitive drum between the first side plate and the second side plate in the first direction. The frame holds a developer cartridge. A lock lever is pivotable about a pivot axis extending in a second direction intersecting with the first direction. The lock lever is movable between a lock position at which the developer cartridge is locked on the frame and a release position at which the developer cartridge is unlocked from the frame.