Developing apparatus and image forming apparatus

A developing apparatus, comprising:

• a frame configured to rotatably support a developing roller;
• a first end portion member provided at one end of the frame in an axial direction of the developing roller so as to be rotatable relative to the frame around a rotation axis parallel to the axial direction;
• and
• a second end portion member provided at another end of the frame in the axial direction so as to be rotatable relative to the frame around the rotation axis,
• wherein the developing apparatus is removably mounted to an apparatus main body of an image forming apparatus in the axial direction,
• wherein at least one end portion member of the first end portion member and the second end portion member has a force receiving portion and a regulating portion,
• wherein the force receiving portion is provided on one side of said one end portion member in a first direction orthogonal to the rotation axis, and receives biasing force from a biasing member of the apparatus main body in a mounting direction when the developing apparatus is mounted to the apparatus main body, and
• wherein the regulating portion is provided on the other side of said one end portion member in the first direction, and is brought into contact with the apparatus main body to regulate movement of the other side of said one end portion member relative to the apparatus main body in a direction opposite to the mounting direction, with a fulcrum being the rotation axis.