Patent ID: 7524041
Filing Date: 2009-04-28
Classification: B41J

Abstract:
1. A pressure producing apparatus, comprising: a sheet member which is formed of a piezoelectric material; a plurality of first electrodes which are embedded in a first area of at least one of a first portion and a second portion of the sheet member, such that the first electrodes are separate from each other in the first area, the first portion and the second portion being opposite to each other in a direction of thickness of the sheet member; a plurality of second electrodes which are embedded in a second area of said at least one of the first and second portions of the sheet member, such that the second electrodes are separate from each other in the second area, the second area being adjacent to the first area in a surface direction parallel to a first surface of the first portion and a second surface of the second portion that are opposite to each other in the direction of thickness of the sheet member; and a liquid-chamber defining member which cooperates with one of the first and second surfaces of the sheet member to define a liquid chamber in which a liquid is accommodated, wherein an electric field is applied between the first electrodes and the second electrodes, so as to produce a difference between an amount of elongation in the surface direction of the first portion of the sheet member and an amount of elongation in the surface direction of the second portion of the sheet member and thereby curve the sheet member in the direction of thickness thereof and change a pressure of the liquid accommodated in the liquid chamber.