PURPOSE: To eliminate the thickening or fixing of residual ink after the suction of ink and the trouble of a positive pressure air generating pump by reducing the pressure in a cap chamber by the air stream passing through the cap chamber at a high speed to suck the residual ink of an ink emitting part and carrying the sucked ink by air to allow a waste ink absorbing member to suck the ink.

CONSTITUTION: A pump 12 for generating positive pressure air, a cap 4 hermetically sealing the ink emitting part of an ink head 1, a waste ink tank 2 having a waste ink absorbing member 9 built therein and the exhaust passage 4b communicating with the waste ink tank 2 from the pump 12 through the cap 4 are provided. The pressure in a cap chamber 4a is reduced by the air stream passing through the cap 4 at a high speed to suck the residual ink of the ink emitting part and the sucked ink is carried by air and absorbed in the waste ink absorbing member 9. As a result, no residual ink flows in the pump 12 at all and no residual pressure also remains in the cap chamber 4a. The thickening or sticking of the residual ink after the suction of ink or the trouble of the pump is eliminated.