Patent ID: 7604327

Claim:
A liquid ejection apparatus which ejects a liquid supplied from a liquid supply source, comprising: a liquid ejection head comprising a plurality of nozzles through which the liquid is ejected; a plurality of pressure chambers each communicating with one of the nozzles; an actuator which applies pressure selectively to liquid in the pressure chambers to eject the liquid through the nozzles; a first liquid channel and a second liquid channel independent of the first liquid channel such that the liquid cannot be transported therebetween outside of the liquid ejection head, the first and second liquid channels communicating the pressure chambers with the liquid supply source; a pressure applying unit which applies pressure to liquid in the first liquid channel; a mode switching unit which switches between two modes of a liquid ejection mode in which liquid is supplied from the liquid supply source through the first and second liquid channels to the pressure chambers to be ejected through the nozzles, and a liquid circulation mode in which the pressure applying unit applies pressure to the liquid in the first liquid channel to circulate the liquid between the liquid supply source and each of the pressure chambers; guides, each of which is provided in one of the pressure chambers and which forces the liquid pressurized by the pressure applying unit and flowed from the first liquid channel into the pressure chambers to flow out of the pressure chambers to the second liquid channel; and communicating channels each communicating one of the pressure chambers and the associated nozzle together; wherein the guides are partition walls each partitioning the associated pressure chamber into a first space and a second space, the first and second spaces communicating with the first and second liquid channels, respectively; the first and second spaces of each of the pressure chambers are connected together only in the vicinity of the associated communicating channel; and the actuator changes a volume of each of the pressure chambers to apply pressure to the liquid in one of the pressure chambers, the actuator being arranged to cover the pressure chambers, and being spaced from the partition walls to form a gap between the actuator and the partition walls.