HEARING PROTECTOR

• US 20110064239A1
• Filed: 04/27/2009
• Published: 03/17/2011
• Est. Priority Date: 05/12/2008
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M China Limited (3M Company)
• Inventors: Håkansson, Johan, Sjöman, Henrik J.
• Granted Patent: US 9,131,310 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: A61F 11/145 electric, e.g. for active noise reduction
• CPC Class Codes: H04R 1/1075 Mountings of transducers in earphones or headphones
• 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 has two closed muffs (2) which sealingly abut against the wearer'"'"'s head, so that there is formed a closed space in each muff (2) and about the user'"'"'s ear. A loudspeaker (4) is disposed interiorly in the muff and has a membrane (5) whose one side is turned to face towards the user'"'"'s ear, and whose opposing side is turned to face towards a closed volume which is defined by the membrane and an enclosure. In order to improve the base reproduction in listening to music, the interior of the enclosure is, via at least one hole or one duct, in communication with the ambient surroundings outside the closed space of the muff (2). In one preferred embodiment, the enclosure comprises a capsule (7) which is integrated part of the loudspeaker (4).

Claims

1. A hearing protector with loudspeakers and comprising, a closed muff (2) disposed at each ear of a user, the muff sealingly abutting against the user'"'"'s head, whereby there is formed an enclosed space in the muff and around the user'"'"'s ear, one loudspeaker (4) disposed in at least one of the muffs and displaying a membrane (5) whose one side is turned to face towards the ear of the user and whose opposing side is turned to face towards a closed volume which is defined by the membrane and an enclosure, and a drive unit for driving the loudspeaker, characterised in that the interior of the enclosure is, via at least one hole or duct, in communication with the ambient surroundings outside the closed space of the muff (2).

2. The hearing protector as claimed in claim 1, characterised in that the enclosure comprises a capsule (7) which is an integrated part of the loudspeaker (4).

3. The hearing protector as claimed in claim 1, characterised in that the enclosure is at least partly a part of the muff (2).

4. The hearing protector as claimed in any of claims 1 to 3, characterised in that there is disposed, interiorly in the closed space of the muff (2), a noise absorbent, and that, in the region between the loudspeaker (4) and the user'"'"'s ear, there is a region without noise absorbent or a region with a noise absorbent with lower damping.

5. The hearing protector as claimed in any of claims 1 to 4, characterised in that the total area (A) of the hole/holes or duct/ducts lies in the range of 5.5>

A>

0.1 mm².

6. The hearing protector as claimed in claim 5, characterised in that the area (A) lies in the range of 0.5>

A>

0.1 mm².

7. The hearing protector as claimed in claim 5 or 6, characterised in that the area (A) is less than 2% of the membrane area of the loudspeaker (4), preferably less than 1% thereof.

8. The hearing protector as claimed in any of claims 2 or 4 to 7, characterised in that the muff (2) has an outer wall (10) facing away from the user'"'"'s ear, and having an aperture in which the capsule (7) of the loudspeaker is sealingly accommodated.

9. The hearing protector as claimed in claim 8, characterised in that there is disposed around the aperture a collar (11) extending towards the user'"'"'s ear and having a radially inwardly directed bead (12) along the free end, the bead being accommodated or snapped into a corresponding circumferential groove (9) along the periphery of the capsule (7).

10. The hearing protector as claimed in any of claims 2 to 7, characterised in that the muff (2) has an outer wall (10) facing away from the user'"'"'s ear, and having an aperture (14) in which is sealingly inserted a fixing portion (18) on a retainer (15) in which the capsule (7) of the loudspeaker (4) is sealingly accommodated, there being disposed, interiorly in the retainer, a cavity (17) in which the aperture or duct of the capsule discharges, and the cavity being in communication with the ambient surroundings outside the closed space of the muff by the intermediary of an aperture or duct in the fixing portion.

11. The hearing protector as claimed in claim 10, characterised in that the retainer (15) consists of a resilient, possibly elastic rubber-like material.

12. The hearing protector as claimed in claim 10 or 11, characterised in that the retainer (15) has a sleeve-shaped portion which surrounds and sealingly abuts against a peripheral, circumferential region of the capsule (7).