Patent ID: 8147043
Filing Date: 2012-04-03
Classification: B41J

Abstract:
1. A back pressure adjustment apparatus for a liquid ejection head, the back pressure adjustment apparatus comprising: a container having a liquid accommodating chamber which is connected to the liquid ejection head and accommodates liquid to be supplied to the liquid ejection head, and a gas accommodating chamber which accommodates gas; a movable film which separates the liquid accommodating chamber and the gas accommodating chamber, and forms a portion of whole walls of the liquid accommodating chamber; a pressure adjustment pump which is connected to the gas accommodating chamber and causes the movable film to deform in such a manner that volume of the gas accommodating chamber is changed, so as to adjust pressure of the liquid accommodated in the liquid accommodating chamber; a gas bubble removal tube, connected to an upper portion of the liquid accommodating chamber, for removing gas bubbles from the liquid accommodating chamber; and a gas bubble removal valve which opens and closes the gas bubble removal tube, wherein the movable film is aligned in a vertical direction.