LIFE SAFETY DEVICE WITH COMPACT CIRCUMFERENTIAL ACOUSTIC RESONATOR

摘要

Low frequency alarm tones emitted by life safety devices are more likely to notify sleeping children and the elderly. Disclosed herein is a life safety device equipped with a novel, compact, circumferential resonant cavity which increases the low frequency (400-600 Hz square wave) acoustic efficiency of an audio output apparatus formed by acoustically coupling an audio output transducer to the resonant cavity.

主权项

1. A life safety device comprising:
a vented housing forming a volume less than two inches thick; an environmental condition sensor located within the housing; an audio output transducer that outputs a tone on the order of 520 Hz, the audio output transducer located within the housing; and an acoustic resonator comprising an arcuate passage having a closed end forming an acoustic node, the acoustic resonator being coupled with the audio output transducer, and the acoustic resonator being located within the housing, wherein:
the audio output transducer and the acoustic resonator are part of an audio output apparatus; andthe audio output apparatus has a cavity performance index (CPI) of at least 1.27 dBA/W-cm3.