US 12,135,251 B2
Piezoelectric element device, piezoelectric element apparatus, and load detection method
Chikara Kojima, Matsumoto (JP)
Assigned to SEIKO EPSON CORPORATION, Tokyo (JP)
Filed by SEIKO EPSON CORPORATION, Tokyo (JP)
Filed on Jun. 30, 2021, as Appl. No. 17/363,400.
Claims priority of application No. 2020-112700 (JP), filed on Jun. 30, 2020.
Prior Publication US 2021/0404889 A1, Dec. 30, 2021
Int. Cl. G01L 1/16 (2006.01); B25J 13/08 (2006.01); G01L 1/10 (2006.01)
CPC G01L 1/167 (2013.01) [G01L 1/106 (2013.01); B25J 13/084 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A piezoelectric element device, comprising:
a substrate including a plurality of vibrating portions having a first vibrating portion and a second vibrating portion;
a piezoelectric element group in which a plurality of piezoelectric elements having a first piezoelectric element and a second piezoelectric element provided in the plurality of vibrating portions are coupled in parallel to each other;
a plurality of load detectors having a first load detector including the first vibrating portion and the first piezoelectric element provided in the first vibrating portion and a second load detector including the second vibrating portion and the second piezoelectric element provided in the second vibrating portion; and
a resin layer covering the piezoelectric element group, wherein
the first load detector resonates at a first resonance frequency,
the second load detector resonates at a second resonance frequency,
the first resonance frequency and the second resonance frequency are different from each other,
the first resonance frequency changes in accordance with a load applied to the first load detector via the resin layer,
the second resonance frequency changes in accordance with a load applied to the second load detector via the resin layer, and
a first resonance frequency change range, which is a changeable range of the first resonance frequency, and a second resonance frequency change range, which is a changeable range of the second resonance frequency, do not overlap each other.