A toner cartridge includes a body including a first toner discharge portion, a discharge shutter configured to rotate relative to the body about a first rotation axis to a discharge position at which toner is allowed to be discharged via the first toner discharge portion and a closed position at which the first toner discharge portion is closed, and a locking member supported by the body and configured to rotate about a second rotation axis different from the first rotation axis to a locked position at which a first interference portion of the discharge shutter located at the closed position is caught by a second interference portion, thereby not allowing the discharge shutter to rotate and an unlocked position at which the discharge shutter is allowed to rotate.

A printer includes a main body, a development cartridge attachable to and detachable from the main body, the development cartridge to supply toner contained in a toner container to an electrostatic latent image formed on a photoconductor, to form a visible toner image, a mounting portion including a toner inlet portion connected to the toner container, where a toner cartridge usable to refill toner in the toner container is mountable to the mounting portion, an inlet shutter rotatably provided in the mounting portion to be rotatable together with the toner cartridge, the inlet shutter rotatable between a blocking position to block the toner inlet portion from receiving toner and an inlet position to open the toner inlet portion to receive toner, a locking unit to selectively lock and unlock the inlet shutter, and a controller to control the locking unit to selectively lock and unlock the inlet shutter based on whether the toner cartridge is mounted to the mounting portion.

A printer includes a main body; a development cartridge attachable to and detachable from the main body, the development cartridge comprising a developing portion in which a photoconductive drum and a developing roller are provided, a waste toner container to receive waste toner removed from the photoconductive drum, a toner container connected to the developing portion and to receive toner, and a toner refilling portion connected to the toner container and to refill toner through the toner refilling portion into the toner container; and a communicating portion provided in the main body to be connected to the toner refilling portion to provide an access the toner refilling portion from outside of the main body when the development cartridge is attached to the main body.

An image forming apparatus and method for determining a toner level and providing a notification are provided. The method of operating an image forming apparatus includes counting a number of times a lower toner hopper receives toner from an in-situ refillable upper toner hopper, calculating an estimate of toner volume transferred from the lower toner hopper to a surface of a photosensitive drum, determining an amount of toner consumed from the in-situ refillable upper toner hopper based on the number of times the lower toner hopper receives toner from the in-situ refillable upper toner hopper and the estimate of toner volume transferred from the lower toner hopper to the surface of the photosensitive drum, and generating an upper toner hopper refill notification when the amount of toner consumed from the in-situ refillable upper toner hopper is determined to exceed a threshold value.

A toner refill cartridge includes a body including a toner chamber containing toner and a toner discharging portion having an entrance connected to one end of the toner chamber in a length direction and an exit to discharge toner outside of the toner refill cartridge, a plunger including a piston that is movably inserted into the toner chamber in the length direction and a packing member located at an end of the piston to push the toner toward the toner discharging portion, a weight part movably accommodated in the toner chamber and having a shape which prevents the weight part from passing through the entrance, and a weight part container provided in the one end of the toner chamber in the length direction such that the weight part can be accommodated therein.

A printer includes a main body, a development cartridge attachable to and detachable from the main body, the development cartridge to supply toner contained in a toner container to an electrostatic latent image formed on a photoconductor, to form a visible toner image, a mounting portion including a toner inlet portion connected to the toner container, where a toner cartridge usable to refill toner in the toner container is mountable to the mounting portion, an inlet shutter rotatably provided in the mounting portion to be rotatable together with the toner cartridge, the inlet shutter rotatable between a blocking position to block the toner inlet portion from receiving toner and an inlet position to open the toner inlet portion to receive toner, a locking unit to selectively lock and unlock the inlet shutter, and a controller to control the locking unit to selectively lock and unlock the inlet shutter based on whether the toner cartridge is mounted to the mounting portion.

A toner refilling interface structure including a toner cartridge, an installation portion, a first toner inlet portion, an inlet shutter, and a locking member. The toner cartridge including a discharge shutter located in or coupled to a body and to switch to a closed position at which a first toner discharge portion of the body is closed and to switch to a discharge position at which the first toner discharge portion is open. The toner cartridge is rotatable about a first rotation axis. The first toner inlet portion is provided in the installation portion to receive toner from the toner cartridge. The inlet shutter is provided in the installation portion to switch to an inflow position at which the first toner inlet portion is open, from a blocked position at which the first toner inlet portion is blocked, by a first rotation of the toner cartridge from an installation position to a first angular position The locking member is provided in the toner cartridge and to lock the discharge shutter at the closed position during the first rotation of the toner cartridge.

Examples described herein relate to a supply valve consistent with the disclosure. For instance, a supply valve to supply print particles to a receptacle, the supply valve may comprise a print particle exit, a print particle entrance perpendicular to the print particle exit, and a liner adjacent to the print particle exit, where the liner is to wipe print particles, when present, from the supply valve responsive to the transition of the supply valve between a closed position and an open position.

An example print component includes a container interface with a guide feature to guide rotation and a rotationally asymmetric key feature. An example toner component includes a recess to receive a toner container, a guide feature to guide rotation of the toner container, and an asymmetric key feature embedded in the guide feature to guide a container material interface towards a component material interface upon rotation. An example container may have a periphery with a rotationally asymmetric surface plane to guide rotation of the container and a protrusion extending from the periphery that has a key feature defined by edges rotationally asymmetric with respect to the periphery. An example container may include a mechanical interface including an asymmetrically-located key feature that, upon rotation of the print material container, generates a sealing force substantially perpendicular to the direction of rotation.

A toner cartridge includes a hollow body having an inner space in which toner is received and a toner discharge portion through which the toner is discharged, a plunger accommodated in the inner space to be movable in a longitudinal direction along the inner space and configured to push the toner through the toner discharge portion to outside of the body, a first hook provided on the body, and a second hook. The second hook has a shape complementary to a shape of the first hook, is provided on the plunger, and is elastically coupled to the first hook when the plunger reaches a bottom dead position.