DIGITAL PRINTING APPARATUS

摘要

A digital printing apparatus including a sheet supply device, printing cylinder, inkjet nozzle portion, sheet delivery device, and conveyance devices. The sheet supply device supplies sheets one by one at a predetermined period. The printing cylinder includes at least one gripper device that grips and holds the sheet, and conveys the sheet while one edge of the sheet supplied from the sheet supply device is held by the plurality of gripper devices. The inkjet nozzle portion discharges ink droplets onto the sheet. The conveyance devices include a plurality of gripper devices including one reversing gripper device that grips and holds the other edge of the sheet, and conveys the sheet printed on one surface, which is received from the printing cylinder in a double-sided printing mode. The sheet is turned by reversing the obverse/reverse surface of the sheet by the reversing gripper device in the process of conveyance.

主权项

1. A digital printing apparatus comprising:
a sheet supply device which supplies sheets one by one at a predetermined period; a printing cylinder which includes at least one gripper device that grips and holds the sheet, and conveys the sheet while one edge of the sheet supplied from said sheet supply device is held by said at least one gripper devices; an inkjet nozzle portion which discharges an ink droplet onto the sheet conveyed by said printing cylinder, and prints on the sheet; a sheet delivery device which discharges the sheet after end of printing by said inkjet nozzle portion; conveyance devices which include a plurality of gripper devices including one reversing gripper device that grips and holds the other edge of the sheet, convey the sheet printed on one surface, which is received from said printing cylinder in a double-sided printing mode, while sequentially transferring the sheet by gripping changes by said plurality of gripper devices, and supply to said printing cylinder the sheet turned by reversing an obverse/reverse surface of the sheet by said reversing gripper device in the process of conveyance; and a nozzle head moving device which brings said inkjet nozzle portion close to said printing cylinder or separates said inkjet nozzle portion from said printing cylinder, said nozzle head moving device including an inkjet nozzle attaching/detaching device which moves said inkjet nozzle portion between a printing position and a retreat position, said inkjet nozzle portion coming close to said printing cylinder to print on the sheet at the printing position, said inkjet nozzle portion retreating radially outside said printing cylinder from the printing position to the retreat position.