Developing device

A developing device comprising:

• a developing container for accommodating a developer;
• a feeding member, including a blade helically extending on a rotation shaft, for feeding the developer in said developing container along the rotation shaft by rotation thereof in a downstream developer feeding direction;
• and
• a discharge opening for permitting discharge of excessive developer, with supply of the developer from said developing container, said discharge opening being provided in a side surface of said developing container opposing said feeding member and being configured to open independently of an amount of the developer in said developing container,
• wherein in an overlapping region with said discharge opening, said blade is rotatable such that said blade moves the developer in the downstream developer feeding direction at a side opposing said discharge opening,
• wherein in the overlapping region with said discharge opening, a winding direction of said blade is such as to ascend toward the downstream developer feeding direction, and
• wherein when a first lower intersection position, with respect to a gravitational direction, between a downstream edge of said discharge opening and a first cross-section perpendicular to a rotational axis of said feeding member and crossing said discharge opening is a first position, and
• when a second lower intersection position, with respect to the gravitational direction, between the downstream edge of said discharge opening and a second cross-section which is perpendicular to the rotational axis of said feeding member and crossing said discharge opening and which is provided downstream of the first cross-section with respect to the developer feeding direction of said feeding member is a second position,
• said discharge opening is configured so that the second position is higher than the first position.