| 摘要 |
PURPOSE:To make it possible to perfectly remove air in an ink pressure chamber, by providing an air vent valve in an ink jet head by connecting one end of an ink supply passage in the vicinity of a nozzle port by a connection hole. CONSTITUTION:An air outflow groove 119 is provided to the ink pressure chamber 102 of a nozzle plate 108 in the side opposite to a nozzle 103 and communicated with an air vent valve part 117 through the hole 121 provided to a fourth upper plate 116. The valve part 117 is formed so that the central valve body 117a thereof is supported so as to leave openings 122 therearound and operated so as to be opened and closed by air pressure in the ink pressure chamber 102 transmitted from the air outflow groove 119 through a hole 120. When pressure is applied to the interior of the ink pressure chamber 102 in replenishing the ink, the valve body 117a is raised and the opening 121 is opened and air in the ink pressure chamber 102 is exhausted to the outside from an air outflow passage 118 through an exhaust hole 122. |
