Earplug and method for manufacturing the same

• US 20060045297A1
• Filed: 08/25/2004
• Published: 03/02/2006
• Est. Priority Date: 08/25/2004
• Status: Active Grant

• Current Assignee: Sonova AG (Sonova Holding AG)
• Original Assignee: Phonak AG (Sonova Holding AG)
• Inventors: Haussmann, Mathias
• Granted Patent: US 7,369,670 B2
• Time in Patent Office: Days
• US Class Current: 381/322
• CPC Class Codes: A61F 11/08 internal, e.g. earplugs
• CPC Class Codes: A61F 11/085 including an inner channel
• CPC Class Codes: A61F 11/145 electric, e.g. for active noise reduction
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: H04R 25/652 Ear tips; Ear moulds hybrid ear moulds or post-processing thereof for their customisation H04R25/659
• CPC Class Codes: H04R 25/658 Manufacture of housing parts
• CPC Class Codes: Y10T 29/49572 Hearing aid component making

Abstract

The invention relates to an active hearing protection earplug comprising a shell (2000) to be worn at least in part in a user'"'"'s ear canal and being adapted to attenuate sound waves arriving at the outer end (2001) of the shell, and an active system (2002, 2010) comprising an input transducer (2024) for converting ambient sound into audio signals, an audio signal processing unit (2028) for processing said audio signals, and an output transducer unit (2010) mounted within the shell for converting said processed audio signals into sound output at the inner end of the shell, wherein the amplification of the active system is negative and wherein the output transducer unit comprises at least two separate outputs (2032, 2034). The invention also relates to a method for manufacturing such an earplug.

Claims

1. An active hearing protection earplug comprising a shell to be worn at least in part in a user'"'"'s ear canal and being adapted to attenuate sound waves arriving at an outer end of said shell, and an active system comprising an input transducer for converting ambient sound into audio signals, an audio signal processing unit for processing said audio signals, and an output transducer unit mounted within said shell for converting said processed audio signals into sound output at an inner end of said shell, wherein amplification of said active system is negative and wherein said output transducer unit comprises at least two separate outputs.

2. The earplug of claim 1, wherein each output of said output transducer unit is connected with a separate sound output tube.

3. The earplug of claim 2, wherein each sound output tube is formed as a cavity integral with said shell.

4. The earplug of claim 2, wherein each sound output tube is at least one of shaped and sized to have acoustic properties different from said other sound output tube(s).

5. The earplug of claim 2, wherein said sound output tubes merge into a common sound outlet tube.

6. The earplug of claim 1, wherein each output of said output transducer unit has a frequency response function, in particular a basic resonance frequency, different from that of the other output(s).

7. The earplug of claim 1, wherein said output transducer unit comprises two of said outputs.

8. The earplug of claim 1, wherein said signal processing unit comprises an active crossover network for said audio signals.

9. The earplug of claim 1, wherein said input transducer is mounted within said shell.

31. The earplug of claim 1, wherein said shell is a hard shell with an elasticity of from shore D-85 to shore D-65 which has an outer surface individually shaped according to a measured inner shape of said user'"'"'s outer ear and ear canal.

32. The earplug of claim 31, wherein said shell is made of polyamide.

33. The earplug of claim 31, wherein said shell is made by an additive build-up process.

34. The earplug of claim 33, wherein said shell is made by a layer-by-layer laser sintering process of a powder material.

10. A method for manufacturing an earplug including a shell to be worn at least in part in a user'"'"'s ear canal and an acoustic output transducer unit, mounted within said shell, for sound output at an inner end of said shell, comprising:

determining a desired sound frequency response function of said output transducer unit when mounted within said shell, establishing an acoustic model of said shell including said output transducer unit, and forming a shell having a receptacle for mounting said output transducer unit within said shell and a sound cavity connecting said output transducer unit to a sound outlet opening at said inner end of said shell, wherein said sound cavity is shaped and sized according to said model in order to tune an actual sound frequency response of said output transducer unit according to said desired sound frequency response of said output transducer unit.

11. The method of claim 10, wherein said desired sound frequency response function and said model relate to said shell when worn in a standard ear canal and outer ear.

12. The method of claim 10, wherein further comprising:

measuring an inner shape of said user'"'"'s outer ear and ear canal, wherein said desired sound frequency response function and said model relate to said shell when worn in the measured user'"'"'s ear canal and outer ear, with said sound cavity thus being individually shaped and sized according to said measured inner shape of said user'"'"'s ear canal and outer ear.

13. The method of claim 10, wherein said output transducer unit comprises two separate outputs, wherein said sound cavity has a Y-like shape with a first sound output tube and a second sound output tube combining at a mixing point into a common sound outlet tube which connects to said sound outlet opening, and wherein said first sound output tube connects to one of said outputs of said output transducer unit and said second sound output tube connects to the other one of said outputs said output transducer unit.

14. The method of claim 10, wherein said earplug is designed as an active hearing protection device including an input transducer and an audio signal processing unit, wherein amplification of an active system comprising said input transducer, said audio signal processing unit and said output transducer unit is negative.

15. An active hearing protection earplug comprising a hard shell to be worn at least in part in a user'"'"'s ear canal, said shell having an elasticity of from shore D-85 to shore D-65 and an outer surface individually shaped according to a measured inner shape of said user'"'"'s outer ear and ear canal and being adapted to attenuate sound waves arriving at an outer end of said shell, and an active system mounted at or within said shell and comprising an input transducer for converting sound waves arriving at the outer end of the earplug into audio signals, a signal processing unit for processing said audio signals, and an output transducer unit for converting said processed audio signals into sound output at an inner end of said shell, wherein amplification of said active system is negative, wherein said output transducer is hard mounted within a predefined cavity within said shell.

16. The earplug of claim 15, wherein said output transducer unit is hard mounted within said cavity by press-fitting.

17. The earplug of claim 15, wherein said output transducer unit is hard mounted within said cavity by an adhesive having an elasticity of from shore D-85 to shore D-65.

18. The earplug of claim 15, wherein said input transducer is hard mounted within a further predefined cavity within said shell.

19. A hearing protection earplug comprising an integral shell to be worn at least in part in a user'"'"'s ear canal and being adapted to attenuate sound waves arriving at an outer end of said shell, said shell comprising a measurement channel formed as a cavity integral with said shell and extending from an outer end of said shell through said shell to an inner end of said shell or into an interior of said shell, said measurement channel comprising, at an outer end thereof, means for acoustically connecting said measurement channel to an external measurement unit in a detachable manner, wherein said shell is a hard shell with an elasticity of from shore D-85 to shore D-65 which has an outer surface individually shaped according to a measured inner shape of said user'"'"'s outer ear and ear canal.

20. The earplug of claim 19, wherein said connecting means comprise an adapter element fixed within an opening of a faceplate provided at said outer end of said shell, said adapter element being adapted to be connected to an external measurement tube in a detachable manner.

22. The earplug of claim 20, wherein said adapter element comprises a thread.

21. The earplug of 20, wherein said adapter element is adapted to be closed by a plug in a detachable manner when not connected to said external measurement tube.

23. Hearing protection earplug comprising a shell to be worn at least in part in a user'"'"'s ear canal and being adapted to attenuate sound waves arriving at an outer end of said shell, said shell comprising a sound passage adapted to pass sound to a sound outlet opening at an inner end of said shell, wherein said sound passage comprises closing means which are adapted to acoustically close said sound passage if a sound pressure level at said closing means exceeds a threshold value and to acoustically open said sound passage if said sound pressure level does not exceed said threshold value.

24. The earplug of claim 23, wherein said closing means are formed integral with said shell.

25. The earplug of claim 23, wherein said closing means comprises a closing element adapted to engage, if experiencing a sound pressure level above the threshold value, with a mating counter-element in order to acoustically close said sound passage, wherein said closing element is biased away from engagement with said counter-element.

26. The earplug of claim 23, wherein said sound passage extends from an outer opening of said shell to said sound outlet opening. 1

27. The earplug of claim 26, wherein said closing means is located at or close to said sound outlet opening.

28. The earplug of claim 23, wherein said sound passage extends from an acoustic output transducer within said shell to said sound outlet opening.

29. The earplug of claim 23, wherein said sound passage splits in a direction away from said sound outlet opening.

30. The earplug of claims 26, wherein said closing means is located at or close to said outer opening of said shell.