Printing device for individually printing webs or sheets of printing substrates

A printing device for individually printing webs, sheets or boards of printing substrates according to the ink jet principle, wherein the printing substrate defines a printing substrate plane and the printing device comprising:

• a machine frame (1);
• a transport device (60) that is designed for transporting the printing substrate in an essentially linear material flow direction (100) within the printing substrate plane;
• two identical printing units (2, 2.1, 2.2, 2.3) that are arranged behind one another in a direction (200) extending transverse to the material flow direction (100), wherein each of the two printing units (2, 2.1, 2.2, 2.3) respectively has a frame (20) and includes;
• a first print head (23), which is designed and can be controlled in such a way that it is suitable for delivering and transferring liquid ink to the printing substrate in a predefined manner;
• a primary reservoir (21) for storing a first quantity of liquid ink;
• a secondary reservoir (22) for storing a second quantity of liquid ink;
• and
• a pump (25) for conveying the liquid ink,
• wherein the primary reservoir (21), secondary reservoir (22), and pump (25) are arranged in the frame (20), primary reservoir (21), the secondary reservoir (22) and the pump (25) are connected to one another and to the first print head (23) to convey the liquid ink to supply the first print head (23) with liquid ink;
• wherein the two printing units (2, 2.1, 2.2, 2.3) respectively have a second print head (24), wherein the first and the second print head (23, 24) of the same printing unit (2, 2.1, 2.2, 2.3) are respectively accommodated in the frame (20) of the printing unit (2, 2.1, 2.2, 2.3) and have a printing region (203.1, 203.2) and a printing plane, the printing planes of the two print heads (23, 24) of a printing unit (2, 2.1, 2.2, 2.3) are identical to the same printing substrate plane (1000), and the printing regions (203.1, 203.2) of the two printing units (2.1, 2.2) alternately either form a common and uninterrupted printing region (204) at least in the transverse direction (200), wherein the printing regions (203.1, 203.2) of the two printing units (2.1, 2.2) directly border on one another or partially overlap one another and respectively form a second overlapping region (212) or form printing regions (203.2, 203.3) that are spaced apart from each other in the transverse direction.