Inkjet head, method for manufacturing same, and inkjet printer

An inkjet printer comprising:

• a housing;
• a carriage movable with respect to the housing;
• and
• an inkjet head mounted to the carriage, wherein the inkjet head comprises:
• a displacement film comprising a driving film operable to expand and contract in a direction perpendicular to a thickness direction of the driving film, the displacement film being operable to undergo a curving deformation in a thickness direction of the displacement film;
• a substrate comprising a hole portion formed therein in a thickness direction thereof and that supports the displacement film such that the displacement film covers the hole portion so as to allow expansion and contraction of the driving film to cause the curving deformation of the displacement film in the thickness direction of the displacement film in an area of the displacement film corresponding to the hole portion;
• an ink discharge portion comprising an ink chamber holding ink and that discharges the ink to outside of the ink discharge portion by having pressure resulting from the curving deformation of the displacement film applied to the ink, wherein the ink discharge portion is disposed on a side opposite to the hole portion of the substrate with respect to the displacement film;
• an upper electrode;
• and
• a lower electrode, wherein the driving film is sandwiched between the upper electrode and the lower electrode in a thickness direction of the driving film so that the upper electrode and the lower electrode apply a voltage across the driving film, wherein the lower electrode is positioned closer to a side of the substrate than the upper electrode and the driving film, and the upper electrode is exposed to an interior of the ink chamber;
• and
• wherein the displacement film further comprises a driven film that is operable to curve in a thickness direction of the driven film along with the expansion and contraction of the driving film;
• and
• wherein the driven film comprises such a part of the substrate in a thickness direction of the substrate as constitutes a wall located to a driving-film side of the hole portion.

A method for producing an inkjet head, the method comprising:

• forming a driving film at a substrate;
• forming a hole portion in the substrate, on a side opposite to a side where the driving film is formed, and supporting a displacement film including the driving film such that the displacement film covers the hole portion so as to allow expansion and contraction of the driving film in a direction perpendicular to a thickness direction of the driving film to cause a curving deformation of the displacement film in a thickness direction of the displacement film in an area of the displacement film corresponding to the hole portion;
• forming an ink discharge portion, through which ink held in a ink chamber is discharged to outside of the ink chamber by the curving deformation of the displacement film, on a side opposite to the hole portion of the substrate with respect to the displacement film;
• and
• forming an upper electrode and a lower electrode, wherein the driving film is sandwiched between the upper electrode and the lower electrode in a thickness direction of the driving film so that the upper electrode and the lower electrode apply a voltage across the driving film, wherein the lower electrode is positioned closer to a side of the substrate than the upper electrode and the driving film, and the upper electrode is exposed to an interior of the ink chamber.

An inkjet head comprising:

• a displacement film comprising a driving film operable to expand and contract in a direction perpendicular to a thickness direction of the driving film, the displacement film being operable to undergo a curving deformation in a thickness direction of the displacement film;
• a substrate comprising a hole portion formed therein in a thickness direction thereof and that supports the displacement film such that the displacement film covers the hole portion so as to allow expansion and contraction of the driving film to cause the curving deformation of the displacement film in the thickness direction of the displacement film in an area of the displacement film corresponding to the hole portion;
• and
• an ink discharge portion comprising an ink chamber holding ink and that discharges the ink to outside of the ink discharge portion by having pressure resulting from the curving deformation of the displacement film applied to the ink, wherein the ink discharge portion is disposed on a side opposite to the hole portion of the substrate with respect to the displacement film;
• an upper electrode;
• and
• a lower electrode, wherein the driving film is sandwiched between the upper electrode and the lower electrode in a thickness direction of the driving film so that the upper electrode and the lower electrode apply a voltage across the driving film, wherein the lower electrode is positioned closer to a side of the substrate than the upper electrode and the driving film, and the upper electrode is exposed to an interior of the ink chamber;
• and
• wherein the substrate has an ink flow path formed therein through which to supply ink to the ink chamber.

An inkjet printer comprising:

• a housing;
• a carriage movable with respect to the housing;
• and
• an inkjet head mounted to the carriage, wherein the inkjet head comprises:
• a displacement film comprising a driving film operable to expand and contract in a direction perpendicular to a thickness direction of the driving film, the displacement film being operable to undergo a curving deformation in a thickness direction of the displacement film;
• a substrate comprising a hole portion formed therein in a thickness direction thereof and that supports the displacement film such that the displacement film covers the hole portion so as to allow expansion and contraction of the driving film to cause the curving deformation of the displacement film in the thickness direction of the displacement film in an area of the displacement film corresponding to the hole portion;
• an ink discharge portion comprising an ink chamber holding ink and that discharges the ink to outside of the ink discharge portion by having pressure resulting from the curving deformation of the displacement film applied to the ink, wherein the ink discharge portion is disposed on a side opposite to the hole portion of the substrate with respect to the displacement film;
• an upper electrode;
• and
• a lower electrode, wherein the driving film is sandwiched between the upper electrode and the lower electrode in a thickness direction of the driving film so that the upper electrode and the lower electrode apply a voltage across the driving film, wherein the lower electrode is positioned closer to a side of the substrate than the upper electrode and the driving film, and the upper electrode is exposed to an interior of the ink chamber;
• and
• wherein the substrate has an ink flow path formed therein through which to supply ink to the ink chamber.

A method for producing an inkjet head, the method comprising:

• forming a driving film at a substrate;
• forming a hole portion in the substrate, on a side opposite to a side where the driving film is formed, and supporting a displacement film including the driving film such that the displacement film covers the hole portion so as to allow expansion and contraction of the driving film in a direction perpendicular to a thickness direction of the driving film to cause a curving deformation of the displacement film in a thickness direction of the displacement film in an area of the displacement film corresponding to the hole portion;
• forming an ink discharge portion, through which ink held in an ink chamber is discharged to outside of the ink chamber by the curving deformation of the displacement film, on a side opposite to the hole portion of the substrate with respect to the displacement film;
• forming an ink flow path within the substrate, wherein ink is supplied to the ink chamber by the ink flow path;
• and
• forming an upper electrode and a lower electrode, wherein the driving film is sandwiched between the upper electrode and the lower electrode in a thickness direction of the driving film so that the upper electrode and the lower electrode apply a voltage across the driving film, wherein the lower electrode is positioned closer to a side of the substrate than the upper electrode and the driving film, and the upper electrode is exposed to an interior of the ink chamber.