Hearing Protector

• US 20070274529A1
• Filed: 11/23/2004
• Published: 11/29/2007
• Est. Priority Date: 11/27/2003
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Svenska AB (3M Company)
• Inventors: Nordin, Henrik, Nilsson, Sigvard
• Granted Patent: US 8,243,943 B2
• Time in Patent Office: Days
• US Class Current: 381/72
• CPC Class Codes: A61F 11/14 external, e.g. earcaps or earmuffs
• CPC Class Codes: H04R 1/1008 Earpieces of the supra-aural or circum-aural type
• CPC Class Codes: H04R 1/1025 Accumulators or arrangements for charging secondary cells per se H01M10/00; charging in general H02J7/00
• CPC Class Codes: H04R 1/1083 Reduction of ambient noise active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06
• CPC Class Codes: H04R 5/033 Headphones for stereophonic communication details thereof, e.g. relating to batteries, cables or control elements H04R1/10

Abstract

A hearing protector comprises a hearing hood (2), a microphone (7), a loudspeaker and an amplifier. The hearing hood (2) has passive noise damping. The microphone (7) 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 (7) to the loudspeaker. The noise damping of the hearing hood (2) 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 (2) and, on the other hand, by sound from the loudspeaker amounts to a maximum, predetermined value.

Claims

1. A hearing protector comprising

a hearing hood with passive noise damping,

a microphone disposed exteriorly on the hearing protector,

a loudspeaker disposed inside the hood, and

an amplifier for amplifying sound signals caught by the microphone and passing the signals on to the loudspeaker,

wherein the noise damping of the hearing hoods is broad-band;

wherein the amplifier has variable amplification and frequency range which corresponds to a frequency range of human speech; and

wherein the amplifier has a maximum predetermined amplification, where a sum total of sound levels that are caused, on the one hand by ambient sound passing through the hood, and on the other hand by sound emitted by the loudspeaker, amounts to a maximum predetermined value.

2. The hearing protector as claimed in claim 1, wherein the amplifier is manually engageable.

3. The hearing protector as claimed in claim 1, wherein a timer for disengaging the amplifier after a predetermined period of time.

4. The hearing protector as claimed in claim 3, wherein the amplifier is manually disengageable.

5. The hearing protector as claimed in claim 1, wherein the amplifier, the microphone, the loudspeaker and a battery are disposed together as a replaceable unit.

6. The hearing protector as claimed in claim 5, wherein the unit is removably disposed in a recess in the hearing hood, a partition between the recess and an interior of the hearing hood having an aperture for the loudspeaker.

7. The hearing protector as claimed in claim 1, wherein the loudspeaker extends into an interior of the hearing hood so as to be close to an ear of a wearer of the hearing protection.