US 11,917,920 B2
Piezoelectric device
Hironari Yamamoto, Nagaokakyo (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on May 17, 2021, as Appl. No. 17/321,564.
Application 17/321,564 is a continuation of application No. PCT/JP2019/039314, filed on Oct. 4, 2019.
Claims priority of application No. 2019-049915 (JP), filed on Mar. 18, 2019.
Prior Publication US 2021/0273154 A1, Sep. 2, 2021
Int. Cl. B06B 1/06 (2006.01); H10N 30/853 (2023.01); H10N 30/87 (2023.01)
CPC H10N 30/853 (2023.02) [B06B 1/0629 (2013.01); H10N 30/87 (2023.02)] 18 Claims
OG exemplary drawing
 
1. A piezoelectric device comprising:
a piezoelectric array including a plurality of piezoelectric pillars, the piezoelectric pillars having a columnar shape and being made of piezoelectric ceramic, and in which the plurality of piezoelectric pillars are provided along a row direction and a column direction in a two-dimensional array, such that the piezoelectric pillars are parallel or substantially parallel to each other in a height direction thereof;
a resin portion located in a gap between the plurality of piezoelectric pillars;
a first electrode including a plurality of first electrode wires extending in the column direction, the plurality of first electrode wires being provided along the column direction of the piezoelectric array and being connected to first end portions of the piezoelectric pillars; and
a second electrode including a plurality of second electrode wires extending in the row direction, the plurality of second electrode wires being provided along the row direction of the piezoelectric array and being connected to second end portions of the piezoelectric pillars; wherein
both of the plurality of piezoelectric pillars and the resin portion resonantly vibrate in a thickness longitudinal vibration mode; and
a resonant frequency of the resin portion is higher than a resonant frequency of the piezoelectric pillars by about 15% or greater.