Patent ID: 8714684

Claim:
A printing apparatus which performs printing on a sheet, comprising: a printing section which performs the printing on the sheet at a printing position; a transport mechanism in which a transport route which guides the sheet to the printing position and a re-transport route which guides the sheet having passed through the printing position to the printing position again are formed, the transport mechanism including an install section to which a transport unit, in which an extended route connected to the re-transport route to form a part of the re-transport route thereby lengthening a length of the re-transport route is formed, is to be installed; a print control section which controls the printing section and the transport mechanism to execute a plurality of kinds of double-sided printing processes having different maximum numbers of sheets present at the same time in the transport mechanism from each other so that in a case that the transport unit is installed to the install section, a double-sided printing process, among the double-sided printing processes, in which a maximum number of sheets is large as compared with a case in which the transport unit is not installed to the install section is executed; and an option detecting section which is configured to detect as to whether or not the transport unit is installed to the install section, wherein the print control section is configured to determine whether or not the transport unit is installed to the install section based on a detection result of the option detecting section, under a condition that the print control section determines that the transport unit is not installed to the install section, the print control section controls the printing section and the transport mechanism to execute a double-side printing processes having a single sheet present at a time in the transport mechanism, and under a condition that the print control section determines that the transport unit is installed to the install section, the print control section controls the printing section and the transport mechanism to execute a double-sided printing processes having a plurality of sheets present at the same time in the transport mechanism.