Developing device and image forming apparatus provided with same

An image forming apparatus, comprising:

• an image carrying body on which a toner image is formed;
• a developing device supplying a developer to the image carrying body to form the toner image on the image carrying body;
• a transfer member transferring the toner image onto a sheet;
• and
• a fixing unit fixing the toner image onto the sheet,
• wherein the developing device includes:
• a developer storing portion storing a developer containing a nonmagnetic toner and a magnetic carrier;
• a developer carrying body receiving the developer from the developer storing portion to supply the developer to a predetermined image carrying body while rotating in a predetermined direction;
• a first regulating member having a first regulating surface that opposes the developer carrying body and regulates a layer thickness of the developer carried on the developer carrying body;
• a second regulating member having a second regulating surface that is positioned more upstream than the first regulating surface with respect to a rotation direction of the developer carrying body and that is set so as to become apart from the developer carrying body toward the upstream side with respect to the rotation direction of the developer carrying body to regulate an amount of the developer conveyed to the first regulating surface, the second regulating surface being arranged with a step formed between the second regulating surface and the first regulating surface;
• and
• a sheet member so attached to the second regulating surface as to cover the step between the first regulating surface and the second regulating surface, wherein
• the sheet member is attached to extend from the second regulating surface onto the first regulating surface, and
• a gap of a predetermined size is set through the sheet member between the first regulating surface of the first regulating member and the developer carrying body.