Patent ID: 7792466

Claim:
An image forming apparatus, comprising: a latent image carrier configured to carry a latent image; and a developing device configured to develop the latent image carried by the latent image carrier with a developer containing toner particles and carriers, the developing device including: a developer carrier configured to carry the developer, a receive-convey screw configured to receive the developer from the developer carrier and to convey the developer in an axial direction of the receive-convey screw, the receive-convey screw including: a receive-convey blade including a lower, outer circumferential end located in a downstream end of the receive-convey blade in the developer conveyance direction of the receive-convey screw, and a slant-convey screw disposed obliquely relative to the axial direction of the receive-convey screw, and configured to receive the developer from the receive-convey screw and to convey the developer upward in an axial direction of the slant-convey screw, the slant-convey screw including: a slant-convey blade including a lower, outer circumferential end located in an upstream end of the slant-convey blade in the developer conveyance direction of the slant-convey screw, the lower, outer circumferential end being located at a height level lower than the lower, outer circumferential end of the receive-convey blade, wherein the developing device further includes a wall having a bottom surface and a top surface provided between the receive-convey screw and the slant-convey screw, the wall including an opening having an upper inner wall and a lower inner wall, the lower inner wall spaced apart from the bottom surface of the wall, the opening opposing the downstream end of the receive-convey blade in the developer conveyance direction of the receive-convey screw, the receive-convey screw transfers the developer to the slant-convey screw via the opening, wherein the lower, outer circumferential end of the slant-convey blade is located at a height level lower than the lower, outer circumferential end of the receive-convey blade at a center line of the lower inner wall in a direction in which the lower inner wall extends, and wherein the lower inner wall of the opening is disposed obliquely relative to the upper inner wall of the opening in an axial direction of the slant-convey screw, and wherein a spaced apart region of the wall between the bottom surface of the wall and the lower inner wall of the opening covers a lower portion of the slant-convey blade.