INK JET RECORDING DEVICE, INK JET RECORDING HEAD, INK JET UNIT, AND PRESSURE RECOVERY METHOD FOR INK JET RECORDING DEVICE

摘要

PURPOSE:To prevent defective discharge of ink caused by bubbles in the ink of an ink jet record head and remove the bubbles efficiently at recovery of discharge. CONSTITUTION:When a filter 1 is provided in an ink feed passage, a valve 7 is not adhered to the filter l by ink flow to be generated by ink discharge at recording, but the valve 7 is adhered to the filter 1 when the speed of the ink flow is increased in operation for recovering discharge so as to cover a part of the filter 1. Thus, a sectional area of a flow passage in the filter 1 decreases, so that a pressure difference above a predetermined quantity is generated in front and back of the filter 1. As a result, the bubbles which can not pass the filter 1 at recording can pass it at recovery of discharge.