Ink system for ink jet matrix printer

Claim 1

In an ink jet matrix printer comprising an ink system having a fluid transport device which optionally, transports thick ink from a first supply container into an ink chamber and, independently thereof, feeds solvent from a second supply container into the ink chamber; supplies ink from this ink chamber under pressure to a write head; and returns ink formed of ink droplets not diverted for writing purposes, from a collection channel into the ink chamber, the collection channel is located across from the write head; wherein the improvement comprises: the transport device is exclusively operated by means of pressurized air, has a connection to a source of pressurized air, and has a suction jet pump; the ink chamber includes: an ink container fluidly connected with the write head; a mixer container which is fluidly connected with the said two supply containers; and a collection container fluidly connected to the collection channel; the ink container is connected to a first air pressure line and the ink therein is under pressure, the ink container fluidly connected to the mixer container by means of a connection line; that the mixer container is connected via a suction line alternatively to the suction jet pump or to a second pressure line; and, that the collection container is connected with the suction jet pump via a line with negative pressure, and with the mixer container via a run-off line, and a valve controlling flow in said run-off line.