Patent ID: 8177344

Claim:
An image recording apparatus for recording images on a recording medium by moving the recording medium and an inkjet head relative to each other, comprising: an ink reservoir for storing ink; a subtank connected to said inkjet head for temporarily storing the ink to be discharged from said inkjet head; an ink force-feed channel interconnecting said ink reservoir and said subtank; a first switch valve mounted on said ink force-feed channel; an ink circulating channel interconnecting said ink reservoir and one of said inkjet head and said subtank; a second switch valve mounted on said ink circulating channel; a pressure regulating mechanism for pressurizing and decompressing the ink stored in said ink reservoir; and a controller comprising a processor and a memory having a program, when executed, causing the processor to control, for preventing sedimentation of components of the ink in the ink circulating channel, said pressure regulating mechanism to, at fixed time intervals, pressurize the ink stored in said ink reservoir in a state where said first switch valve is opened and said second switch valve is closed, and to decompress the ink stored in said ink reservoir in a state where said first switch valve is closed and said second switch valve is opened.