Image forming apparatus with residual toner conveyance feature for improved detection/collection of accumulated residual toner

摘要

An image forming unit includes an image bearing member. A transfer member transfers a toner image on the image bearing member to a record member. A cleaning member cleans toner adhered onto the transfer member. A toner container contains toner cleaned by the cleaning member. A toner sensor, which is positioned at a center area of said toner container in a direction orthogonal to a moving direction of the image bearing member and detects an amount of collected toner. A conveyance member conveys the collected toner and includes first screws to convey toner to a position corresponding to an area in which the first area is excluded from the second area in a direction toward the detection position, and second screws to convey toner to a position between said first screws and the detection position in a direction opposite to the direction toward the detection position.