A drum cartridge includes: a drum frame to which a developing cartridge including a storage medium having an electrical contact surface is detachably attachable; a photosensitive drum; a transfer roller; and a conveying roller. The drum is rotatable about a first axis extending in a first direction and positioned at one end portion of the frame in a second direction. The transfer roller is rotatable about a second axis extending in the first direction and in contact with the drum. The conveying roller is rotatable about a third axis extending in the first direction and separated from the transfer roller in the second direction. A first opening of the frame is positioned between the transfer roller and the conveying roller in the second direction. The electrical contact surface is exposed to an outside through the first opening in a case where the developing cartridge is attached to the frame.

A device that replenishes developer to a developer unit and includes a storage for storing developer, an agitation member, and a vibration plate. The agitation member has a blade shape and is rotationally driven to agitate the developer in the storage. The vibration plate extends from a top portion towards a bottom portion of the storage along a rotation direction of the agitation member, and includes a vibration portion that vibrates due to contact with the agitation member undergoing rotation. A top end of the vibration plate is fixed and a bottom end of the vibration plate is a free end, and there is a gap between the vibration portion and an inner wall of the storage. The vibration plate is provided with an engagement protrusion towards the free end that engages with the agitation member and causes the agitation member undergoing rotation to deform then spring back.

If a user is not familiar with the operation for the developer supply container, the rotating operation for the developer supply container may be insufficient, so that developer supply container does not reach a predetermined operating position, with the result of abnormal developer supply. by increasing a rotation load of a second gear 6 which is in an operable connection with a drive gear member 12 of the developer receiving apparatus 10 by a function of a locking member 7, the developer supply container 1 mounted to the developer receiving apparatus 10 is rotated toward the supply position. After the developer supply container 1 rotates to the supply position, the locking by the locking member 7 is released, by which the rotation load applied to the second gear 6 is reduced, so that drive transmission, thereafter, to the feeding member 4 for developer supply is smooth.

A cartridge includes a shutter that opens and closes when the cartridge is attached and detached to a developing unit or image forming apparatus. The cartridge includes a casing having a chamber with a first opening at one end portion allowing toner to flow out of the casing. The cartridge includes a cover that covers the first opening, movable with the casing and having a second opening allowing toner to flow out of the cover. The shutter is located at the one end portion and has a protrusion further from the one end portion than the cover. The developing unit supports the protrusion when the cartridge is mounted thereon, and the casing pivots with the cover relative to the developing unit between a first position where the shutter closes the second opening and a second position where a third opening of the shutter overlaps the second opening.

A drum cartridge includes: a drum frame to which a developing cartridge including a storage medium having an electrical contact surface is detachably attachable; a photosensitive drum; a transfer roller; and a conveying roller. The drum is rotatable about a first axis extending in a first direction and positioned at one end portion of the frame in a second direction. The transfer roller is rotatable about a second axis extending in the first direction and in contact with the drum. The conveying roller is rotatable about a third axis extending in the first direction and separated from the transfer roller in the second direction. A first opening of the frame is positioned between the transfer roller and the conveying roller in the second direction. The electrical contact surface is exposed to an outside through the first opening in a case where the developing cartridge is attached to the frame.

A drum cartridge includes: a drum frame to which a developing cartridge including a storage medium having an electrical contact surface is detachably attachable; a photosensitive drum; a transfer roller; and a conveying roller. The drum is rotatable about a first axis extending in a first direction and positioned at one end portion of the frame in a second direction. The transfer roller is rotatable about a second axis extending in the first direction and in contact with the drum. The conveying roller is rotatable about a third axis extending in the first direction and separated from the transfer roller in the second direction. A first opening of the frame is positioned between the transfer roller and the conveying roller in the second direction. The electrical contact surface is exposed to an outside through the first opening in a case where the developing cartridge is attached to the frame.

A toner case includes a case main body, first and second agitators, and a transmitting mechanism. The case main body is configured to store a toner. The first and second agitators are configured to rotate and to agitate the toner in the case main body. A transmitting mechanism is configured to transmit rotation to the first and second agitators. The transmitting mechanism stops transmission of the rotation to the second agitator while the transmitting mechanism continues the transmission of the rotation to the first agitator, when driving torque of the second agitator is equal to or more than a first set value.

A cartridge includes a shutter that opens and closes when the cartridge is attached and detached to a developing unit or image forming apparatus. The cartridge includes a casing having a chamber with a first opening at one end portion allowing toner to flow out of the casing. The cartridge includes a cover that covers the first opening, movable with the casing and having a second opening allowing toner to flow out of the cover. The shutter is located at the one end portion and has a protrusion further from the one end portion than the cover. The developing unit supports the protrusion when the cartridge is mounted thereon, and the casing pivots with the cover relative to the developing unit between a first position where the shutter closes the second opening and a second position where a third opening of the shutter overlaps the second opening.

A toner comprising a toner particle, the toner particle comprising a binder resin, wherein the toner particle comprises a monoester wax, and a fatty acid metal salt A is present on a surface of the toner particle, when X(A) is defined as a coverage ratio of the surface of the toner particle by the fatty acid metal salt A, as determined by X-ray photoelectron spectroscopy and S(A) is defined as the coverage ratio of the surface of the toner particle by the fatty acid metal salt A, as determined by analysis of a scanning electron microscope image, the formulae below are satisfied:

S(A)0.03(1)

X(A)0.250(2)

0.248S(A)/X(A)1.000(3).

A drum cartridge includes: a drum frame to which a developing cartridge including a storage medium having an electrical contact surface is detachably attachable; a photosensitive drum; a transfer roller; and a conveying roller. The drum is rotatable about a first axis extending in a first direction and positioned at one end portion of the frame in a second direction. The transfer roller is rotatable about a second axis extending in the first direction and in contact with the drum. The conveying roller is rotatable about a third axis extending in the first direction and separated from the transfer roller in the second direction. A first opening of the frame is positioned between the transfer roller and the conveying roller in the second direction. The electrical contact surface is exposed to an outside through the first opening in a case where the developing cartridge is attached to the frame.