US Patent 7593672 Developer supplying apparatus and developing apparatus having the same

A developer supplying apparatus includes a developer lump prevention unit that reduces the aggregation of developer into lumps in the path, which defines the supply passage of developer from the developer cartridge, in which the developer is stored, to the developing cartridge, which houses the developing roller. The developer lump prevention unit includes a developer lump removal member disposed in the path and a driving mechanism to drive the developer lump removal member to move in the path to prevent the developer lumps from forming and/or to break up lumps that had already formed in the path.