Patent ID: 7048363

Claim:
An ink jet recording apparatus comprising: a record head mounted on a carriage and reciprocated in a width direction of recording material; supply means, mounted on the carriage together with the record head, for supplying ink to the record head via an ink replenishment passage from an ink cartridge forming a main tank, wherein air pressure generated by an air pressurizing pump is applied to the ink cartridge, and the supply means is replenished with ink from the ink cartridge by the action of the air pressure; a pressure regulation valve, provided to an air flow passage from the air pressurizing pump to the ink cartridge, the valve being opened upon reception of a predetermined or more air pressure for maintaining air pressure in the air flow passage within a predetermined range; and a pressure detector, provided to the air flow passage, for receiving the air pressure and detecting a pressure state, wherein driving of the air pressurizing pump is controlled based on output of the pressure detector.