Patent ID: 6932462

Claim:
An ink let head comprising: a substrate having a plurality of grooves each for receiving ink and extending along a longitudinal direction; a nozzle plate connected to the substrate and having a plurality of nozzle apertures each disposed in communication with respective ones of the grooves; ink storing means for storing ink; an ink chamber plate connected to the substrate and having an ink chamber for supplying ink from the ink storing means to the grooves; means defining an ink flow path for transporting ink from the ink storing means to the ink chamber of the ink chamber plate; a filter disposed in the ink flow path in a direction generally perpendicular to the longitudinal direction of each of the grooves; and a flow path substrate connected between the ink storing means and the ink chamber plate, at least portions of the ink flow path being formed in the flowpath substrate, the ink flow path having a tubular communicating passage having a first end connected to the ink storing means and a second end, an ink reservoir in which the filter is disposed to divide the ink reservoir into an upstream space disposed on a lower side of the filter and a downstream space disposed on an upper side of the filter opposite, the lower side, an ink introduction passage for transporting ink along a flow direction generally perpendicular to the longitudinal direction of each of the grooves and having a first end connected to the second end of the tubular communicating passage and a second end connected to the upstream space, an ink supply passage having a first end connected to the downstream space and a second end connected to the ink chamber plate for supplying ink to the ink chamber, the ink supply passage being inclined downwardly relative to a horizontal line disposed generally parallel to the flow direction of ink in the ink introduction passage, and each of the ink introduction passage, the ink supply passage, the upstream space, and the downstream space having a thickness smaller than an inner diameter of the tubular communicating passage.