US 11,867,308 B2
Piezoelectric actuator and fluid control valve
Shigeyuki Hayashi, Kyoto (JP); and Tadahiro Yasuda, Kyoto (JP)
Assigned to HORIBA STEC, Co., Ltd., Kyoto (JP)
Filed by HORIBA STEC, Co., Ltd., Kyoto (JP)
Filed on Nov. 20, 2019, as Appl. No. 16/689,878.
Claims priority of application No. 2018-229032 (JP), filed on Dec. 6, 2018.
Prior Publication US 2020/0185588 A1, Jun. 11, 2020
Int. Cl. F16K 31/00 (2006.01); H02N 2/00 (2006.01); H10N 30/20 (2023.01); H10N 30/50 (2023.01); H10N 30/80 (2023.01); H10N 30/853 (2023.01)
CPC F16K 31/007 (2013.01) [H02N 2/001 (2013.01); H10N 30/20 (2023.02); H10N 30/50 (2023.02); H10N 30/802 (2023.02); H10N 30/853 (2023.02)] 4 Claims
OG exemplary drawing
 
1. A fluid control valve comprising:
a piezoelectric actuator comprising:
a piezoelectric stack wherein a piezoelectric ceramic layer and an electrode layer are alternately stacked,
a DC voltage application circuit that displaces the piezoelectric stack by applying a DC voltage to at least a part or whole of the piezoelectric stack, and
a vibration voltage application circuit that vibrates the piezoelectric stack by applying a voltage having a predetermined frequency or above to at least a part or whole of the piezoelectric stack, wherein
the piezoelectric stack comprises:
a driving block to be connected to the DC voltage application circuit; and
a vibration block to be connected to the vibration voltage application circuit,
the driving block and the vibration block are arranged in a line next to each other along a longitudinal direction of the piezoelectric ceramic layer and the electrode layer,
the fluid control valve further comprises a valve body that is driven by the piezoelectric actuator and whose position to a valve seat is adjusted,
the DC voltage application circuit applies the DC voltage to the piezoelectric stack so as to make the position of the valve body to the valve seat at a predetermined position, and
the vibration voltage application circuit vibrates the valve body in the vicinity of the predetermined position.