SEAL IN MICRO ELECTRO-MECHANICAL INK EJECTION NOZZLE

摘要

A micro electro-mechanical device embodied within an ink ejection nozzle having an actuating arm that is caused to move an ink displacing paddle when heat inducing electric current is passed through the actuating arm (28) is disclosed. The paddle (27) is located in an ink chamber (24) and the actuating arm (28) passes through an actuator aperture (54) in the chamber (24). The chamber (24) is partly defined by a straight edge portion (10) on an upper wall (23) of the ink chamber (24). The actuating arm (28) carries a second planar wall (9) which covers the actuation aperture (54) and which is movable relative to the edge portion (10) when the actuating arm (28) and paddle (27) are moved to eject a droplet (D). Upon movement of the actuating arm (28) the second wall (9) moves relative to the edge portion (10) and a meniscus (M) is created between the edge portion (10) and the second wall (9) which forms a seal between the second wall (9) and the edge portion (10) of the chamber wall (23).