Abstract
A microphone unit includes a housing having a first main surface and a second main surface disposed opposite each other. The housing surrounds an inner chamber which includes a resonance chamber. The first main surface includes a concave indentation facing toward the inner chamber. A hearing aid, including a substantially cylindrical battery and a microphone unit is also provided.
Claims
1. A microphone unit, comprising: an inner chamber including a resonance chamber; a housing surrounding said inner chamber; said housing including a first main surface and a second main surface disposed opposite each other; and said first main surface including a concave indentation penetrating into said inner chamber.
2. The microphone unit according to claim 1, wherein said concave indentation extends toward said inner chamber across an entire length of said first main surface.
3. The microphone unit according to claim 1, wherein said second main surface includes a convex bulge.
4. The microphone unit according to claim 1, wherein said second main surface has a plurality of sound inlet openings.
5. The microphone unit according to claim 1, wherein at least one of said first main surface or said second main surface includes a circuit board.
6. The microphone unit according to claim 1, which further comprises a micro-electro-mechanical system for generating a microphone signal from an ambient sound.
7. The microphone unit according to claim 1, which further comprises a plurality of electronics components disposed within said housing and related to preprocessing of a microphone signal.
8. A hearing aid, comprising: a substantially cylindrical battery having a radius and jacket portion with a section; and a microphone unit according to claim 1, said concave indentation of said first main surface of said microphone unit being adapted to said radius of said battery permitting said microphone unit to be situated along said section of said jacket portion of said battery.
Description
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
(1) FIG. 1 is a fragmentary, diagrammatic, top-plan view of a hearing aid including a battery unit and a microphone unit according to the prior art;
(2) FIG. 2 is a fragmentary top-plan view of a hearing aid including a battery and a microphone unit, the main surfaces of which are curved along the battery;
(3) FIG. 3 is a cross-sectional view of a hearing aid including an alternative embodiment of a curved microphone unit;
(4) FIG. 4 is a perspective view of the microphone unit according to FIG. 3; and
(5) FIG. 5 is a longitudinal-sectional view of the microphone unit according to FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
(6) Referring now in detail to the figures of the drawings, in which parts and sizes that are the same are provided with the same reference signs, and first, particularly, to FIG. 1 thereof, there is seen a diagrammatic, top-plan view of a hearing aid 1 which includes a battery 2 and a microphone unit 4 according to the prior art. The hearing aid 1 in this case includes an outer housing 6 which is only partially illustrated, for the sake of better clarity. Clamps 8 for securing the battery 2 are formed into the outer housing 6. During operation of the hearing aid 1, the microphone unit 4, which is also situated in the outer housing 6, generates a microphone signal from an ambient sound. The microphone signal is further processed in the hearing aid 1 in a user-specific manner. Due to the cylindrical shape of the battery 2, the microphone unit 4 cannot be arbitrarily compactly mounted on the battery 2, so that the outer housing 6 becomes larger and voids 9, which are difficult to utilize, are formed in an inner chamber of the hearing aid 1. Even a configuration of the microphone unit 4 that is tilted tangentially with respect to the battery 2 would not change much in this case, and would only result in a structural complexity that is increased due to the tilting and, therefore, a more difficult attachment of the microphone unit 4.
(7) FIG. 2 diagrammatically shows a top view of a hearing aid 1 including a battery 2 and a microphone unit 4 which has been partially adapted to the shape of the battery 2. Only a portion of an outer housing 6 of the hearing aid 1 is shown in this case as well, for the sake of better clarity. The microphone unit 4 includes a housing 10 having a first main surface 12 and a second main surface 14 positioned opposite the first main surface 12. The first main surface 12 is concavely indented toward the interior of the microphone unit 4, and the second main surface 14 is convexly bulged outward. The battery 2 can now engage into a concave indentation 16 of the first main surface 12, which has been formed in this manner, in such a way that the microphone unit 4 can be situated in the region of the clamps 8 along a section 18 of a jacket portion 20 of the battery 2.
(8) FIG. 3 diagrammatically shows a cross-sectional representation of a hearing aid 1 including a variant of a microphone unit 4 which is an alternative to the embodiment represented in FIG. 2. In this case, the microphone unit 4 is not situated in the region of one of the clamps 8, but rather directly on the battery 2, so that, due to the concave indentation 16 of the first main surface 12 of the microphone unit 4, the microphone unit extends along the jacket portion 20 for the section 18. The curvature of the concave indentation 16 is adapted to the radius of the battery 2 in this case. The second main surface 14 of the microphone unit 4 includes a convex bulge 22 which corresponds to the concave indentation 16 of the first main surface 12 and is likewise adapted to the radius of the battery 2.
(9) FIG. 4 shows an oblique view of the microphone unit 4 according to FIG. 3. The microphone unit 4 is surrounded by a housing 10 including a first main surface 12 and a second main surface 14 positioned opposite the first main surface 12. The first main surface 12 forms a concave indentation 16 toward an inner chamber surrounded by the housing 10, and the second main surface 14 forms a convex bulge 22 corresponding to the concave indentation 16. A sound inlet opening 24 is formed in the second main surface 14. An ambient sound can reach through the sound inlet opening 24 to the inner chamber surrounded by the housing 10, where an electrical signal is generated from the ambient sound by signal-generating components which are not represented in greater detail in FIG. 4. The second main surface 14 is formed in this case by a circuit board 26 which is provided with the sound inlet opening 24. An acoustic horn 28 is situated on the circuit board 26, on the sound inlet opening 24 toward the inner chamber, in order to improve sound conduction into the inner chamber of the microphone unit 4 and for avoiding diffractions and interferences. In addition, contact electrodes 29 are situated on the circuit board 26. The microphone unit 4 outputs a microphone signal through the contact electrodes 29 to the hearing aid 1 and, optionally, the contact electrodes 29 are used for supplying power to active components in the microphone unit 4.
(10) FIG. 5 shows a longitudinal-sectional representation of the microphone unit 4 according to FIG. 3. The housing 10 surrounds an inner chamber 30. An ambient sound can be conducted into the inner chamber 30 through the sound inlet opening 24, along the acoustic horn 28 situated on the circuit board 26 which forms the second main surface 14. The inner chamber 30 is used in this case as a resonance chamber 32 for the ambient sound. A MEMS microphone 34, which is soldered to the circuit board 26, includes a MEMS membrane 36. The MEMS membrane 36 together with an electrode 38 soldered on the circuit board 26, in principle forms a capacitor microphone. The electrode 38 is provided with sound holes 40 in order to improve sound transmission with respect to the resonance chamber 32. The electrical signal generated at the MEMS microphone 34 is now fed to a preliminary stage 42 which preprocesses the electrical signal, in particular by using a preamplifier, a dynamic compressor, and an A/D converter, and provides the preprocessed signal to the hearing aid, through the contact electrodes 29, for further processing. The concavely indented, first main surface 12 can be produced, in this case, together with lateral faces 44 of the housing 10, in a shared production process, for example by using injection molding or deep drawing, which simplifies production and reduces costs.
(11) Although the invention was illustrated and described in greater detail by using the preferred exemplary embodiment, the invention is not restricted by this exemplary embodiment. Other variations can be derived therefrom by a person skilled in the art, without departing from the scope of protection of the invention.
(12) The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention. List of reference signs: 1 hearing aid 1, 1 hearing aid 2 battery 4 microphone unit (according to the prior art) 4, 4 microphone unit 5 outer housing 6, 6 outer housing 8 clamps 9 voids 10 housing 12 first main surface 14 second main surface 16 concave indentation 18 section 20 jacket portion 22 convex bulge 24 sound inlet opening 26 circuit board 28 acoustic horn 29 contact electrode 30 inner chamber 32 resonance chamber 34 MEMS microphone 36 MEMS membrane 38 electrode 40 sound holes 42 preliminary stage 44 lateral faces
