Patent ID: 8155574

Claim:
A waste developer collecting device comprising: a collecting container that collects waste developer discharged from an image forming unit including a developing unit for developing an electrostatic latent image with a developer; a conveying unit that is disposed in the collecting container, rotates about a shaft, and conveys the waste developer entering into the collecting container in the collecting container; a detection window that is formed on an upper surface of the collecting container in a part of the collecting container on a downstream side in a conveying direction of the waste developer conveyed by the conveying unit; and a guide that is formed on the detection window to correspond to an inflow direction at the time in a case where the waste developer is collected in the collecting container, and that is conveyed by the conveying unit, wherein Y, Z, and W are in the range of 40% to 60% of X, where X is a distance from a terminal end of the conveying unit in the collecting container to an end portion of the collecting container in a direction of the shaft, Y is a distance from the terminal end of the conveying unit to an upper end of the collecting container, in a section orthogonal to the shaft of the conveying unit in the collecting container, Z is a distance from the terminal end of the conveying unit to an side end of the collecting container, in the section orthogonal to the shaft of the conveying unit in the collecting container, and W is a distance from the terminal end of the conveying unit in the collecting container to a detection position of the detection window in the direction of the shaft.