US 10,889,108 B2
Print head, liquid ejection apparatus, and piezoelectric element control circuit
Tomokazu Yamada, Shiojiri (JP); and Motonori Chikamoto, Shiojiri (JP)
Assigned to Seiko Epson Corporation
Filed by Seiko Epson Corporation, Tokyo (JP)
Filed on Mar. 25, 2019, as Appl. No. 16/362,774.
Claims priority of application No. 2018-057650 (JP), filed on Mar. 26, 2018.
Prior Publication US 2019/0291419 A1, Sep. 26, 2019
Int. Cl. B41J 2/045 (2006.01); B41J 2/14 (2006.01)
CPC B41J 2/04541 (2013.01) [B41J 2/04581 (2013.01); B41J 2/14233 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A print head comprising:
a first piezoelectric element that includes a first electrode supplied with a drive signal and a second electrode supplied with a reference voltage signal and is displaced by a difference in electric potential between the first electrode and the second electrode;
a second piezoelectric element that includes a third electrode supplied with the drive signal and a fourth electrode supplied with the reference voltage signal and is displaced by a difference in electric potential between the third electrode and the fourth electrode;
a cavity that is filled with a liquid ejected from a nozzle along with the displacement of the first piezoelectric element and the second piezoelectric element;
a vibration plate that is disposed between the cavity and the first piezoelectric element and the second piezoelectric element;
a first switch circuit that switches between supplying and not supplying the drive signal to the first electrode;
a second switch circuit that switches between supplying and not supplying the drive signal to the third electrode;
a third switch circuit that switches between electrically connecting and not electrically connecting the first electrode and the third electrode; and
a NOR circuit,
wherein the NOR circuit receives inputs of
a first control signal for controlling the first switch circuit and switching between supplying and not supplying the drive signal to the first electrode, and
a second control signal for controlling the second switch circuit and switching between supplying and not supplying the drive signal to the third electrode, and
wherein the NOR circuit outputs a third control signal for controlling the third switch circuit and switching between electrically connecting and not electrically connecting the first electrode and the third electrode.