<P> The Klaxon horn's characteristic sound is produced by a spring - steel diaphragm with a rivet in the center that is repeatedly struck by the teeth of a rotating cogwheel . The diaphragm is attached to a horn that acts as an acoustic transformer and controls the direction of the sound . </P> <P> In the first klaxons, the wheel was driven either by hand or an electric motor . American inventor Miller Reese Hutchison (later chief engineer of Thomas Edison) patented the mechanism in 1908 . The Lovell - McConnell Manufacturing Co. of Newark, New Jersey bought the rights to the device and it later became standard equipment on General Motors cars . Franklyn Hallett Lovell Jr., the founder, coined the name klaxon from the Ancient Greek verb klazō, "I shriek". </P> <P> Klaxons were first fitted to automobiles and bicycles in 1908 . They were originally powered by six - volt dry cells, and from 1911 by rechargeable batteries . Later hand - powered versions were used as military evacuation alarms and factory sirens . The Klaxon is also remembered for its use as a submarine dive alarm in the Second World War . </P> <P> The Klaxophone is a musical instrument that makes use of the Klaxon's unique sound . </P>

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