The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 02, 2020
Filed:
Feb. 28, 2018
Yamaha Corporation, Hamamatsu-shi, JP;
Yupo Corporation, Tokyo, JP;
Tomoya Miyata, Hamamatsu, JP;
Kunio Hiyama, Hamamatsu, JP;
Seiichiro Iida, Tokyo, JP;
Hiroshi Koike, Ibaraki, JP;
Hidekazu Kodama, Tokyo, JP;
YAMAHA CORPORATION, Hamamatsu-Shi, JP;
YUPO CORPORATION, Tokyo, JP;
Abstract
A sensor unit capable of protecting a piezoelectric element and detecting vibration and sound is provided. The sensor unit comprises a sheet-like piezoelectric element having a porous layer, and a sound propagation sheet covering at least one face of the piezoelectric element and permitting transmission of sound from a first face toward a second face of the sound propagation sheet. A difference in acoustic pressure level between the sound incident on the sound propagation sheet and the transmitted sound is preferably no greater than 10 dB. A surface density of the sound propagation sheet is preferably from 0.03 g/mto 100 g/m. The sound propagation sheet is preferably flexible and preferably has voids. The sensor unit preferably further comprises a sound insulation sheet covering another face of the piezoelectric element and substantially preventing transmission of sound from a second face toward a first face of the sound insulation sheet.