Toner fillable cartridge having protrusions engageable with a development case shutter

A developing assembly for an image forming apparatus, comprising:

• a developing unit including a case having an outer wall with a toner introduction port defined therein and a toner cartridge support formed thereon, a developing sleeve exposed at one side of the case opposed to the toner introduction port, and a displaceable case shutter coupled to the case adjacent to the toner cartridge support and sealable over the toner introduction port;
• a toner cartridge attachable to the support, said toner cartridge having a toner body having first and second ends;
• a toner exhaust port located between the first and second ends of the toner body, said toner body being rotatable with respect to the developing unit;
• a toner box shielding member rotatable with respect to said toner body to open and close the toner exhaust port as the toner body is rotated;
• and
• a pair of protrusions formed adjacent each side of the toner box shielding member, each said pair of protrusions being structured to engage and displace the case shutter upon rotation of said toner body.

A developing unit in an image forming apparatus for attachment with a removable toner cartridge, comprising:

• a case having a case shutter positionable to selectively open and close a toner introduction port defined on the case;
• a developing sleeve exposed at one side of the case opposed to the toner introduction port;
• and
• a rotatable toner cartridge attachable to a toner cartridge support formed on the case, wherein the toner cartridge includes at least one protrusion that engages with and causes displacement of said case shutter to open and close said toner introduction port.