Sheet stacker, image forming apparatus, and sheet conveyance control method

An image forming apparatus comprising:

• an image forming device to form an image on a sheet;
• a sheet stack table on which the sheet is stacked after an image is formed on the sheet;
• a sheet reversing section disposed above the sheet stack table, the sheet reversing section defining a sheet reverse passage to reverse a direction of conveyance of a sheet fed to the sheet reversing section, the sheet reversing section including:
• a first sheet guide to guide a bottom face of the sheet, and
• a second sheet guide disposed downstream from the first sheet guide in a sheet conveyance direction in which the sheet is fed to the sheet reversing section, the second sheet guide attachable to and removable from an apparatus body, the second sheet guide to guide the bottom face of the sheet.

A sheet conveyance control method comprising:

• determining whether a job involves sheet feeding to a sheet reverse passage;
• detecting whether a guide cover to cover a sheet reverse passage is open when the job involves the sheet feeding to the sheet reverse passage;
• and
• inhibiting a sheet conveying operation when the guide cover being open is detected.