Patent ID: 7708383
Filing Date: 2010-05-04
Classification: B41J

Abstract:
1. An ink jet head comprising: a plate-like substrate having an ejection port bored through said plate-like substrate; an ink guide formed of a flat plate and provided at a position corresponding to said ejection port of said plate-like substrate, a tip portion of said ink guide having an upwardly tapered and convex shape, penetrating through and beyond said ejection port and projecting from said ejection port so as to be disposed on an ink ejecting side of said ejection port substrate, and said ejection port and said tip portion of said ink guide forming an ink meniscus; and an ejection means for ejecting ink of said ink meniscus formed by said tip portion of said ink guide and said ejection port as ink droplets, wherein a periphery of said ejection port convexly projects in a ring shape on said plate-like substrate so as to surround said ejection port and project upwardly from an upper surface of said plate-like substrate along an ejection direction of said ink droplets to form a convexly-projecting portion, wherein a tip portion of the convexly-projecting portion of said periphery of said ejection port that convexly projects along said ejection direction has an acute angle, wherein said ink meniscus is held by said tip portion of said ink guide and the acute angled tip portion of said convexly-projecting portion of said periphery of said ejection port, wherein parts of said convexly-projecting portion of said periphery of said ejection port are removed by a predetermined width, and wherein removed portions are provided at both sides of a convex portion of said tip portion of said ink guide disposed in parallel to ink flow, said both sides of said convex portion disposed on an ink inflow side and an ink outflow side of said ejection port.