Developing apparatus for providing developer to an image bearing member and image forming apparatus having the developing apparatus

A developing apparatus, comprising:

• a developer bearing member that encloses a magnet roller having a plurality of magnetic poles and is rotatable;
• a wall that forms a developer storing chamber for storing a magnetic developer therein;
• a restricting member configured to restrict a layer thickness of the magnetic developer carried on the developer bearing member;
• a moving member configured to move the magnetic developer carried on the developer bearing member before the magnetic developer is restricted by the restricting member, the moving member being rotatable and brought into contact with a surface of the developer bearing member, the moved developer being on the developer bearing member after the moving member moves the developer on the developer bearing member;
• and
• a control portion configured to control rotational operation of the developer bearing member and the moving member,
• wherein, at a contact position between the developer bearing member and the moving member, assuming that a moving speed vector of a surface of the developer bearing member is taken as R and a moving speed vector of a surface of the moving member is taken as r, the control portion controls rotational operation of the developer bearing member and the moving member such that a direction of a vector R-r during image formation and a direction of a vector R-r during non-image formation are opposite to each other, and
• wherein during the image formation, a rotation direction of the developer bearing member and a rotation direction of the moving member are opposite to each other, and a rotation speed of the developer bearing member is lower than a rotation speed of the moving member;
• and
• during the non-image formation, the moving member is stopped and the developer bearing member rotates.