Dennison, Scheiner, Schultz & Wakeman
Surface mount electromagnetic sound producing device
 A casing is provided to be mounted on a printed circuit. The casing has a lower casing and an upper casing. An actuator is provided in the casing, and an armature is supported in the casing so as to be vibrated by the actuator. A sound emanating hole is formed in a peripheral side wall of the upper casing, and a pressure releasing hole is formed in a peripheral side wall of the lower casing. 
Citizen Electronics Co., Ltd.
G
G10K
inventional
Shigehisa
Watanabe