The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 17, 2017
Filed:
Oct. 01, 2015
Google Inc., Mountain View, CA (US);
Gary J. Morris, Morgantown, WV (US);
Google Inc., Mountain View, CA (US);
Abstract
Low frequency alarm tones emitted by life safety devices are more like to notify sleeping children and the elderly. Disclosed herein is a life safety device equipped with a novel, compact, quarter-wave, folded resonant cavity which significantly increases the low frequency (400-700 Hz square wave) acoustic efficiency of an audio output transducer when the folded resonant cavity is acoustically coupled to the transducer forming an audio output apparatus. The folded resonant cavity is comprised of undulating, annular, acoustic passages to significantly reduce the length of the resonant cavity, thereby permitting the audio output apparatus to fit within the housing of conventional size life safety devices such as, but not limited to, residential and commercial smoke alarms and carbon monoxide alarms. Battery powered embodiments of the audio output apparatus comprising a folded resonant cavity passed audibility tests for low frequency alarm tones in smoke alarms specified by UL217.