Class 181/19 - Alarms and indicators

Subclass of Class 181 - Acoustics
Definition: Alarms or indicators of a speaking-tube.
No. of patents: 4
Last issue date: 08/19/1997

Number	Title	Issue Date
5659157	7th order acoustic speaker A loudspeaker system has specific exterior dimensions and specific interior dimensional correlations which has at least a first electroacoustical transducer having a vibratable diaphragm for converting an input electrical signal into a corresponding acous...	08/19/1997
4825800	Marine horn installation A horn assembly for installation within an opening in a boat structure having an exterior surface and an interior surface, is disclosed. The horn assembly includes a noise generator component whose output is directed through a trumpet member having an inl...	05/02/1989
4669683	Moveable safety railing A pivotable safety railing for a platform such as a helicopter landing pad is disclosed. The safety railing includes a suitable hand railing of sufficient height to protect a person on the landing pad, and mounted on a pivot shaft extending along an edge ...	06/02/1987
4505358	Voice communicator Direct voice communication with simultaneous two-way transmission is possible with a communicator having the earpiece of the communicator at one station connected by flexible plastic tubing to the mouthpiece of a communicator at another station, the two s...	03/19/1985

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