Patent ID: 6497475
Filing Date: 2002-12-24
Classification: B41J

Abstract:
A liquid discharge head comprising:a plurality of discharge ports for discharging liquid; a plurality of liquid flow paths which are always in communication with each of said discharge ports at one end, each having a bubble generating area for creating a bubble in the liquid; bubble generating means for generating energy to create and grow the bubble; a plurality of liquid supply ports arranged for respective ones of said liquid flow paths to be in communication with a common liquid supply chamber; and a movable member supported with a minute gap to said liquid supply port on said liquid flow path side, and provided with a free end, the area of said movable member surrounded at least by an edge of the free end and both sides of said movable member continued therefrom being made larger than an opening area of said liquid supply port facing the liquid flow path, and having a period for said movable member to close and essentially cut off said opening area during the period of substantially isotropical growing of the entire bubble by said bubble generating means on said discharge port side after the application of driving voltage to said bubble generating means, and said movable member beginning to be displaced from the position of closing and essentially cut off said opening area to said bubble generating means side in said liquid flow path during the period of the portion of bubble created by said bubble generating means on said discharge port side being grown after the period of the same movable member to close and essentially cut off said opening area, making liquid supply possible from said common liquid supply chamber to said liquid flow path, wherein given the maximum volume of bubble growing in said bubble generating area on said discharge port side as Vf, and given the maximum volume of bubble growing in said bubble generating area on said liquid supply port side as Vr, the relationship Vf>Vr â€ƒis true at all times.