Patent ID: 7578581
Filing Date: 2009-08-25
Classification: B41J

Abstract:
1. An ink jet printer, comprising: an ink jet head comprising an ink passage body and an actuator, the ink passage body comprising a nozzle, an ink chamber communicating with the nozzle, and a pressure chamber located between the nozzle and the ink chamber, the actuator comprising a piezoelectric element facing the pressure chamber, the piezoelectric element comprising a piezoelectric layer, a first electrode connected with a front face of the piezoelectric layer, a second electrode connected with a back face of the piezoelectric layer, and a first insulator located between the second electrode and the ink passage body; and a device that maintains the electric potentials of the ink passage body and the second electrode such that the electric potential of the ink passage body is equal to or below the electric potential of the second electrode, the ink passage body comprises a plurality of nozzles, a plurality of pressure chambers, and a contact formed on a surface of the ink passage body, each nozzle corresponds with a different pressure chamber, the actuator comprises a plurality of piezoelectric elements, each piezoelectric element faces a different pressure chamber, the piezoelectric elements share the piezoelectric layer and the second electrode, each piezoelectric element has its own first electrode, the device comprises a wiring board and a conductive connector, the wiring board comprises: a board, a first wiring formed on the board, a second wiring formed on the board, and a first main wiring formed on the board, wherein the first wiring is connected with the second electrode, the second wiring is connected with the ink passage body, the first main wiring branches into the first wiring and the second wiring, the piezoelectric layer comprises a through hole formed therethrough, the conductive connector is inserted into the through hole, the conductive connector is connected with the second electrode, the first wiring is connected with the conductive connector, and the second wiring is directly connected with the contact.