Birch, Stewart, Kolasch & Birch, LLP
Sound producing device for an electronic instrument such as a telephone
A sound producing device has an electroacoustic transducer mounted in a case. A sound discharging nozzle is projected from the case and communicated with an upper chamber above the electroacoustic transducer.
Citizen Electronics Co., Ltd.
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inventional inventional additional
Shigehisa
Watanabe