Patent ID: 6275594
Filing Date: 2001-08-14
Classification: H04R

Abstract:
A piezoelectric acoustic device comprising:a piezoelectric vibrator including a metal vibrating plate and a piezoelectric ceramic element joined to said metal vibrating plate;a casing including a front side wall and a rear side wall arranged on both sides of said piezoelectric vibrator so as to define a space therebetween in which said piezoelectric vibrator is received; anda drum arranged on an outside of said front side wall so as to extend in a direction across said front side wall;said piezoelectric vibrator and front side wall being arranged so as to define a chamber therebetween;said drum being formed therein with a passage in a manner to communicate with said chamber;said drum being so arranged that a center thereof is deviated from a center of said front side wall toward an outer peripheral portion of said front side wall.