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. 14, 2012
Filed:
Nov. 23, 2004
Henrik Nordin, Forsheda, SE;
Sigvard Nilsson, Värnamo, SE;
Henrik Nordin, Forsheda, SE;
Sigvard Nilsson, Värnamo, SE;
3M Svenska Aktiebolag, , SE;
Abstract
A hearing protector comprises a hearing hood (), a microphone (), a loudspeaker and an amplifier. The hearing hood () has passive noise damping. The microphone () is disposed exteriorly on the hearing protector, while the loudspeaker is disposed inside the hood. The amplifier amplifies and transmits the signals from the microphone () to the loudspeaker. The noise damping of the hearing hood () is broad band. The frequency range of the amplifier corresponds to the frequency range of human speech. The amplification of the amplifier is variable and the greatest amplification is such that the sum total of the sound levels that are caused, on the one hand, by ambient sound passing through the hood () and, on the other hand, by sound from the loudspeaker amounts to a maximum, predetermined value.