Patent ID: 7452059
Filing Date: 2008-11-18
Classification: B41J

Abstract:
1. A liquid ejection apparatus, comprising: a nozzle through which liquid is ejected; a pressure chamber which accommodates the liquid to be ejected from the nozzle; a supply side flow path which fills the liquid from a supply system into the pressure chamber; an actuator which is provided on at least one wall of the pressure chamber and changes a volume of the pressure chamber; and a drive signal generating device which generates a drive signal including at least a first drive signal having a time period T a relationship between the time period T when the actuator is operated by means of the drive signal to generate, in the nozzle, a pressure having a prescribed cycle in which a negative pressure acting in a direction which causes the pressure chamber to expand, and a positive pressure acting in a direction which causes the pressure chamber to contract arise alternately, a relationship between an absolute value of a first negative pressure Pn wherein the following relationship is satisfied  where ln is a length of the nozzle; An is a surface area of the nozzle; ls is a length of the supply side flow path; As is a surface area of the supply side flow path; ρ is a density of the liquid; v is a viscosity of the liquid; c is a speed of sound in the liquid; V is a removed volume of the liquid accommodated in the pressure chamber when a pressure P is generated by the actuator; and X is a removed volume of total of a volume of the liquid ejected from the nozzle, a volume of the liquid returning to the supply side flow path, and a volume of the liquid compressed due to application of the pressure P.