PURPOSE: To provide an automatic prevention of clogging at a nozzle by a method wherein an ink feeding system and a cleaning liquid feeding system are changed over to feed cleaning liquid to the nozzle when a power supply is turned off.

CONSTITUTION: IV of a solenoid valve 18 is kept ON while ink jet recording device is operated, a pre-adjusted ink is fed to a nozzle 5 and injected therefrom. In this cace, a solenoid valve 19 is also turned on, a compressed air is flowed to a check valve 23, an air tank 24, IN, of the solenoid valve 19, into a cleaning liquid tank 21 via OUT. Cleaning liquid 22 is fed by the compressed air into IN 2 of the valve 18 via filter 16 (Fig. a). When a power supply is turned off (Fig. b), relays Ry-1, Ry-2 are turned off, contact points of the relays Ry-1, Ry-2 are changed over as shown in Fig. c, so that SV of the valve 18 which is making on and off of the cleaning liquid 22 is conducted, letting the nozzle 5 inject cleaning liquid and then the nozzle 5 is cleansed.