Patent ID: 7630670

Claim:
A developing apparatus for developing an electrostatic image on an image bearing member at a developing position, said developing apparatus comprising: a developer container, which contains a developer including a toner and a carrier; a rotary member, which holds said developer container, and rotatively moves said developer container relative to said developing position; an opening portion provided in said developer container and through which the developer is supplied or discharged; a valve swingable to open and close said opening portion, said valve being located at an opened position when said developer container is at said developing position; a restricting wall, which restricts a movement of said valve in an opening direction of said valve by contacting with said valve when said valve is in said opened position; and an irregularity portion formed on at least one of a contact surface of said valve with said restricting wall, and a contact surface of said restricting wall with said valve, wherein each of a height of said irregularity portion and a width of said irregularity portion is larger than a sum of a diameter of said carrier and a double diameter of said toner.