A developing cartridge includes: a housing extending in a first direction; a developing roller; a memory held at the housing; a holder holding an electrical contact surface; and a relay component electrically connecting the memory to the electrical contact surface. The developing roller is rotatable about an axis extending in the first direction. The developing roller is positioned at one end portion of the housing in a second direction. The holder is movable relative to the housing in at least one of the second direction and a third direction crossing the first direction and the second direction. The third direction also crosses the electrical contact surface.

A developing cartridge for use with a drawer including a photosensitive drum and an electric terminal. The developing cartridge includes a casing, a developing roller, a storage medium and a holder. The casing is configured to accommodate developing agent therein. The developing roller is rotatable about an axis extending in a first direction. The developing roller is movable with the casing. The storage medium has an electrical contact surface. The holder holds the electrical contact surface and is movable with the casing. The casing is movable relative to the drawer in accordance with movement of the drawer from a first position in which developing roller is separated from the photosensitive drum and the electrical contact surface is separated from the electric terminal to a second position in which the developing roller is in contact with the photosensitive drum and the electrical contact surface is in contact with the electric terminal.

A conduction mechanism includes: a conductive bearing that rotatably supports a rotary shaft; a non-conductive axial positioner that has a cylinder externally fitted to the bearing; and a contact terminal attached to an outer circumferential surface side of the cylinder. The cylinder has a slit, and the contact terminal has an abutment piece that is exposed to an inner circumferential surface side of the cylinder from the slit and abuts an outer circumferential surface of the bearing.

A developing device is detachably supported by an image forming apparatus. The developing device includes a housing that can store developer inside the housing, at least one rotating member rotatably provided for the housing, a first support shaft composed of a conductive member and disposed at an axial end of the rotating member, and a support member including a first bearing portion that supports the first support shaft and constituting a side face of the housing in an axial direction of the rotating member. The first bearing portion includes a first guide portion. The first guide portion protrudes outward from an outer surface of the support member and configured to be guided to an installation position of the developing device during installation of the developing device in the image forming apparatus.

A replaceable unit for an electrophotographic image forming device according to one example embodiment includes an electrical contact positioned on a first side of a housing of the replaceable unit for contacting an electrical contact in the image forming device. A guide on the first side of the housing is positioned closer to a front of the housing than the electrical contact and leads rearward toward the electrical contact. The guide includes an inside surface that faces inward sideways toward a second side of the housing. At least a portion of the inside surface is angled inward sideways from front to rear permitting contact between the inside surface and an electrical connector in the image forming device to draw the electrical connector in the image forming device inward sideways relative to the replaceable unit during insertion of the replaceable unit into the image forming device.

A replaceable unit for an electrophotographic image forming device according to one example embodiment includes an electrical contact positioned on a first side of a housing of the replaceable unit for contacting an electrical contact in the image forming device. A guide on the first side of the housing is positioned closer to a front of the housing than the electrical contact and leads rearward toward the electrical contact. The guide includes an inside surface that faces inward sideways toward a second side of the housing. At least a portion of the inside surface is angled inward sideways from front to rear permitting contact between the inside surface and an electrical connector in the image forming device to draw the electrical connector in the image forming device inward sideways relative to the replaceable unit during insertion of the replaceable unit into the image forming device.

There are demands for stable connections of contact points between a process cartridge, including a development device, and an image forming device. A development contact point, a first contact point, and a second contact point are disposed in this order on the inside in a perpendicular direction with respect to an insertion direction in which a development device is inserted into an image forming apparatus.

A toner cartridge according to one example embodiment includes a housing having a reservoir for holding toner. A first latch-receiving shelf is positioned on a first longitudinal end of the housing and a second latch-receiving shelf is positioned on a second longitudinal end of the housing. Contact surfaces on top portions of the first and second latch-receiving shelves are positioned to contact corresponding first and second latches in an image forming device. The contact surface of the first latch-receiving shelf is positioned lower than a first rotational axis of a first drive coupler of the toner cartridge and higher than a second drive coupler of the toner cartridge. The contact surface of the second latch-receiving shelf is positioned lower than at least a portion of a first electrical contact of the toner cartridge and higher than at least a portion of a second electrical contact of the toner cartridge.

A developing cartridge includes: a housing extending in a first direction; a developing roller; a memory held at the housing; a holder holding an electrical contact surface; and a relay component electrically connecting the memory to the electrical contact surface. The developing roller is rotatable about an axis extending in the first direction. The developing roller is positioned at one end portion of the housing in a second direction. The holder is movable relative to the housing in at least one of the second direction and a third direction crossing the first direction and the second direction. The third direction also crosses the electrical contact surface.

A developing cartridge may include a developing roller including a developing roller shaft extending in a first direction, a casing, and a developing electrode, or a pivotable member configured to be electrically connected to the developing roller shaft. The developing electrode or pivotable member has a first end portion electrically connected to the developing roller shaft and a second end portion located farther away from the developing roller shaft than the first end portion, the second end portion being pivotable about a rotation axis extending in the first direction with respect to the first end portion.