Patent ID: 7731349

Claim:
A printing machine comprising: a transfer device including a conveyor having suction holes formed therethrough for transferring cardboard sheets one by one; a suction device for applying a suction force on one of the two surfaces of each of the cardboard sheets, which one of two surfaces faces said conveyor; and ink jet heads located to face the other of the two surfaces of each of the cardboard sheets and be spaced apart therefrom; wherein said ink jet heads are located in such a manner that a desired distance is maintained between tips of the ink jet heads and said the other surface to be printed, and said ink jet heads, extending in a width direction of said cardboard sheet, include ink jet nozzles from each of which ink droplets are jetted out toward said the other surface; said ink jet heads further including skirts, located upstream and downstream in a transferring direction of the cardboard sheets, for preventing the ink droplets from deflecting in an air space between the ink jet nozzle and the other surface of the cardboard sheet by a component of the suction force applied in the transferring direction, said skirts being provided in such a manner that said skirts extend from said ink jet heads toward said the other surface and have a width, extending in the width direction of the cardboard sheet, so as to form a partition in the air space between said ink jet nozzles and said the other surface of the cardboard.