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:
Aug. 27, 1996
Filed:
Sep. 02, 1994
David A Hotvet, Savage, MN (US);
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
An ear device protects a user from damaging sound levels while permitting the user to hear and understand conversation in a noisy environment. The device includes an enclosure system for at least partially isolating the user's ear drums from ambient sounds, at least on directional microphone, an adaptive band pass filter and a speaker. The adaptive band pass filter further includes adaptive high pass and adaptive low pass filters which adaptively and independently control the range of the pass band depending upon the characteristics of the noise in the user's environment. A speaker transmits the processed signal to the user. The adaptive filter also includes a detector connected to receive the processed signal which controls the gain of the system to prevent overcompression of the audio signal. The adaptive filter further includes an adaptive compression circuit utilizing multiple time constants to control the response time of the adaptive filter under various conditions.