Image forming apparatus and processing unit

A processing unit that is provided in an image forming apparatus that includes an image forming portion for forming an image on a recording sheet and is that performs a calibration process for the image formed by the image forming portion and to form a calibration chart on the recording sheet by the image forming portion in order to perform the calibration process, the processing unit being attachable to and removable from an image forming apparatus main body provided with the image forming portion,

• the processing unit comprising:
• a transport path that transports the recording sheet with the image formed thereon by the image forming portion;
• a coating portion that performs a coating process that forms a coating film on the recording sheet that is being transported on the transport path;
• and
• a reading portion that reads the calibration chart on the recording sheet that is being transported on the transport path;
• wherein the coating portion is disposed on an upstream side in a recording sheet transport direction of the reading portion on the transport path, and
• wherein the transport path includes a main transport path that has a branching portion formed thereon, and a sub transport path that is branched from the main transport path at the branching portion, and
• the coating portion and the reading portion are arranged on the sub transport path.

An image forming apparatus, comprising:

• an image forming portion that forms an image on a recording sheet;
• a transport path that transports the recording sheet with the image formed thereon by the image forming portion;
• and,
• a coating portion that performs a coating process that forms a coating film on the recording sheet that is being transported on the transport path;
• wherein the coating portion is disposed on an upstream side in a recording sheet transport direction of a reading portion on the transport path, and
• a calibration process is performed for an image formed by the image forming portion, and the calibration chart is formed on the recording sheet by the image forming portion in order to perform the calibration process;
• and,
• the image forming apparatus, further comprising:
• the reading portion that reads the calibration chart on the recording sheet that is being transported on the transport path, and
• wherein the coating portion and the reading portion are arranged such that a distance between a coating process portion that performs the coating process on the recording sheet in the coating portion and a reading process portion that reads the calibration chart in the reading portion is larger than a maximum transport length for transporting the recording sheet of a maximum size.

An image forming apparatus, comprising:

• an image forming portion that forms an image on a recording sheet;
• a transport path that transports the recording sheet with the image formed thereon by the image forming portion;
• and,
• a coating portion that performs a coating process that forms a coating film on the recording sheet that is being transported on the transport path;
• wherein the coating portion is disposed on an upstream side in a recording sheet transport direction of a reading portion on the transport path, and
• a calibration process is performed for an image formed by the image forming portion, and the calibration chart is formed on the recording sheet by the image forming portion in order to perform the calibration process;
• and,
• the image forming apparatus, further comprising:
• the reading portion that reads the calibration chart on the recording sheet that is being transported on the transport path, and
• a processing unit that is attachable to and removable from an image forming apparatus main body including the image forming portion,
• wherein the transport path, the coating portion, and the reading portion are arranged in the processing unit, and
• wherein the processing unit includes a first processing unit provided with the coating portion and a second processing unit provided with the reading portion, and
• wherein the first processing unit is attachable to and removable from both of the image forming apparatus main body and the second processing unit,
• the second processing unit is attachable to and removable from both of the first processing unit and the image forming apparatus main body, and
• both of the first and the second processing units comprise a frame member in common and the transport path in common that allow the reading portion to be disposed instead of the coating portion in the first processing unit and that allow the coating portion to be disposed instead of the reading portion in the second processing unit.