Image forming apparatus with pivotable transfer unit positioning portion

An image forming apparatus comprising:

• an apparatus body comprising an image bearing member configured to bear a toner image;
• a transfer unit comprising a transfer portion configured to transfer the toner image on the image bearing member onto a sheet, the transfer unit being pivotably supported with respect to the apparatus body such that the transfer portion is capable of coming into contact with and being separated from the image bearing member;
• an opening/closing unit disposed at a position farther from the apparatus body than the transfer unit is, and openably and closably supported with respect to the apparatus body;
• a positioning portion provided on the apparatus body, pivotably supported with respect to the apparatus body and configured to position the transfer unit with respect to the apparatus body;
• and
• an urging portion configured to urge the positioning portion so as to pivot,
• wherein the transfer unit comprises an abutting portion configured to abut a fixed portion provided in the apparatus body, and is configured to be positioned with respect to the apparatus body as a result of the abutting portion abutting the fixed portion,
• wherein the positioning portion comprises:
• a first engagement portion configured to engage with the opening/closing unit at a first position;
• a second engagement portion configured to engage with the opening/closing unit at a second position further from a pivot center of the transfer unit than the first position;
• and
• a pressing portion configured to press the abutting portion, and
• wherein the opening/closing unit comprises:
• a third engagement portion configured to press the first engagement portion and cause the positioning portion to pivot such that the pressing portion is separated from the abutting portion in a course of a closing operation of the opening/closing unit;
• and
• a fourth engagement portion configured to engage with the second engagement portion and cause the positioning portion to pivot.