US Patent 7798610 Ink jet printing head

A groove for a separate liquid chamber opening is provided in the vicinity of a location in a first separate liquid chamber to which a cantilever element is fixed and the groove extends overall in a vertical direction of the separate liquid chamber. The flow resistance of flow across the cantilever element from the upper side to the lower side of the separate liquid chamber through the opening is sufficiently small compared to the flow resistance of flow through the other small gap. Therefore, the ink flow from a common liquid chamber to the lower side of the cantilever element in each separate liquid chamber, which is caused with every ink ejection, passes through substantially two separate liquid chamber openings. As a result, the stagnation of ink flow in the first separate liquid chamber is reduced and the bubbles are smoothly flushed out.