Patent Description:
Various combinations of receivers and microphones have been used in relation to hearing devices, i.e. hearing aids/hearables, earbuds and the like. The role of the microphone is to detect the sound pressure level generated by the receiver in the ear canal. By detecting the sound pressure level with the microphone the sound pressure level generated by the receiver in the ear canal can be monitored and limited.

Typical combinations of receivers and microphones are for example discussed in prior art references <CIT>, <CIT>, and <CIT>. These references both discuss in line implementations of receiver/microphone arrangements where the microphones are arranged in line with the respective receivers. When inserted into the ear canal the microphones are positioned closer to the ear drum than the respective receivers.

The in line arrangements suggested in both <CIT> and <CIT> appear disadvantageous in that the positioning, and in particular the orientation, of the microphones (with their sound inlets facing the ear drum) makes them vulnerable to, for example, ear wax, moisture or other undesired objects being present in the ear canal. In particular, moisture from the ear canal may potentially enter the microphone and thus damage it due to electrical short circuiting, whereas ear wax may potentially block the sound inlet opening of the microphone.

It may thus be seen as an object of embodiments of the present invention to provide a receiver/microphone arrangement where the microphone is less vulnerable and thus protected against for example ear wax and moisture while still being positioned close to the ear drum in the ear canal.

It may be seen as a further object of embodiments of the present invention to provide a receiver/microphone arrangement with an improved fit rate.

The above-mentioned object is complied with by providing, in a first aspect, an acoustical assembly according to claim <NUM>. It is adapted to be inserted into an ear canal, said acoustical assembly comprising.

wherein the nozzle further comprises a microphone unit mount adapted to house at least part of the microphone unit.

The acoustical assembly of the present invention is advantageous in that the mutual positioning of the at least one sound outlet opening, the receiver unit mount and the microphone unit mount form, in combination, an elongated structure which improves the fit rate of the overall acoustical assembly.

Preferably, the microphone unit is arranged in the microphone unit mount in such a way that a sound inlet opening of the microphone unit is oriented towards an interior portion of the microphone unit mount of the nozzle. This is advantageous in that the orientation of the microphone unit prevents that ear wax, moisture or other undesired objects block the sound inlet opening of the microphone unit or damage the microphone unit.

The acoustical assembly of the present invention is further advantageous due to its simple design where a receiver unit and a microphone unit are attached to the same nozzle in an in line arrangement. Preferably, the at least one sound outlet opening of the nozzle is arranged between the receiver unit mount and the microphone unit mount. The simple design also facilitates that different receiver units and different microphone units may be combined. Further, the sound inlet of the microphone unit and the sound outlet of the receiver unit are spatially separated which makes it less susceptible to acoustic leaks.

In the present context a receiver unit is to be understood as a unit being capable of generating sound pressure waves, such as audio sound, in response to an electrical drive signal applied thereto. The receiver unit may be a moving armature type receiver unit. A microphone unit is to be understood as a unit being capable of detecting sound pressure waves, such as audio sound, and generate an electrical signal in response thereto. The microphone unit may be a MEMS microphone unit, an electret microphone, or a microphone comprising a biased membrane.

As addressed above, the microphone unit is arranged in the microphone unit mount in such a way that its sound inlet opening is oriented towards, i.e. facing, an interior portion of the microphone unit mount of the nozzle. Thus, the sound inlet opening of the microphone unit is not oriented towards the ear drum or the ear canal. Instead the sound inlet opening of the microphone unit faces the nozzle which is advantageous in that this orientation prevents, as mentioned above, that ear wax, moisture or other undesired objects blocking the sound inlet opening of the microphone unit or damage the microphone unit.

Preferably, the nozzle defines a longitudinal centre axis, and the receiver unit and the microphone unit preferably are arranged along said longitudinal centre axis. In this manner the overall shape of the acoustical assembly may become a longitudinal structure that fits easily into a typical ear canal. Preferably, the receiver unit and the microphone unit are arranged symmetrically around, and in line with, said longitudinal centre axis.

As already mentioned, the microphone unit is arranged in the microphone unit mount in such a way that its sound inlet opening is oriented towards, (or facing), an interior portion of the microphone unit mount of the nozzle. In order to facilitate this advantageous orientation of the microphone unit, the microphone unit mount of the nozzle preferably comprises an indentation into which indentation the microphone unit is at least partly arranged. The microphone unit may thus be arranged in the indentation with its sound inlet opening facing the bottom surface of the indentation. As already addressed the role of the microphone unit is to detect the sound pressure level generated by the receiver in the ear canal. In order to fulfil this role the microphone unit mount preferably comprises at least one sound channel adapted to guide sound pressure waves from the ear canal to the sound inlet opening of the microphone unit, although the sound inlet opening is oriented away from the ear canal.

The acoustical assembly preferably comprises a wax protection member adapted to be attached to the microphone unit mount of the nozzle. Preferably this wax protection member is replaceable. The wax protection member preferably is attached to the microphone unit mount via a user friendly click-on locking mechanism. This click-on locking mechanism is advantageous in that it allows the wax protection member as well as the microphone unit be easily attached to, or easily detached from, the microphone unit mount. The wax protection member is adapted to prevent that ear wax from the ear canal reaches the sound inlet opening of the microphone unit.

Thus, the role of wax protection member is to prevent that ear wax blocks the sound inlet opening of the microphone unit which may increase the life span of the microphone unit. Moreover, the wax protection member is adapted to maintain the microphone unit in a fixed position relative to the microphone unit mount of the nozzle. The wax protection member preferably comprises at least one sound inlet opening adapted to be aligned with the at least one sound channel of the microphone unit mount. The dimensions of the at least one sound inlet opening of the wax protection member may be smaller than the corresponding dimensions of the at least one sound channel of the microphone unit mount. The at least one sound inlet opening of the wax protection member may then act as a spatial filter or mesh for ear wax or other undesired objects.

The at least one sound outlet opening of the nozzle preferably is arranged between the receiver unit mount and the microphone unit mount. In particular, the at least one sound outlet opening of the nozzle may be arranged between the receiver unit mount and the microphone unit mount though closest to the microphone unit mount.

The number of sound outlet openings in the nozzle may be chosen to meet specific demands. Thus, preferably, a single sound outlet opening of the nozzle is arranged between the receiver unit mount and the microphone unit mount. Alternatively, a pair of oppositely arranged sound outlet openings may be arranged between the receiver unit mount and the microphone unit mount.

Preferably, the acoustical assembly further comprises a dome-shaped positioning member adapted to ensure correct positioning of the acoustical assembly in the ear canal. Preferably this dome-shaped positioning member is replaceable. Preferably this dome-shaped positioning member is flexible. The dome-shaped positioning member may be attached to the nozzle at a position between the receiver unit mount and the microphone unit mount. By dome-shaped is meant that the positioning member may take the shape of a part of a dome. The flexibility of the dome-shaped positioning member is advantageous in that the positioning member may then, due to its flexibility, adapt to the shape and contours of almost any ear canal and thus minimise undesired acoustical leakage. Moreover, the dome-shaped positioning member is symmetrical around the longitudinal centre axis so the acoustical performance of the acoustical assembly is insensitive to rotations of the acoustical assembly around the longitudinal centre axis. The acoustical assembly may further comprise a deflection member at least partly surrounding the microphone unit mount. The deflection member is preferably replaceable. Preferably this deflection member is flexible. The dome-shaped positioning member and the deflection member preferably form a one-piece structure of the same, preferably flexible material, such as silicone.

The one-piece structure may comprise at least one sound outlet opening aligned with the at least one sound outlet opening of the nozzle, and at least one sound inlet opening for the microphone unit. The at least one sound inlet opening for the microphone unit is preferably arranged through the deflection member. Alternatively, the at least one sound inlet opening for the microphone unit may be arranged between the positioning member and the deflection member, such as immediately beneath the deflection member.

In a second aspect the present invention relates to a hearing device comprising an acoustical assembly according to the first aspect.

The present invention will now be described in further details with reference to the accompanying figures where.

As already discussed, the present invention relates to an acoustical assembly comprising a receiver unit and a nozzle (or spout) secured thereto. Moreover, a microphone unit is secured to the nozzle in such a way that its sound inlet opening is oriented towards, i.e. facing, the interior of the nozzle in order to prevent that ear wax, moisture or other undesired objects block the sound inlet opening of the microphone unit or damage the microphone unit.

Referring now to <FIG>, a cross-sectional schematic view of an acoustical assembly <NUM> comprising a receiver unit <NUM>, a nozzle <NUM> comprising three portions <NUM>, <NUM>, <NUM> and a microphone unit <NUM> is depicted. The receiver unit <NUM> comprises a sound outlet opening <NUM> through which opening <NUM> sound pressure waves escape the receiver unit <NUM>. The receiver unit <NUM> is adapted to generate sound within the audible range in response to a provided drive signal. Similarly, the microphone unit <NUM> comprises a sound inlet opening <NUM> through which opening <NUM> incoming sound pressure waves enter the microphone unit <NUM>. The microphone unit <NUM> provides an electrical output signal in response to detected sound pressure waves. The receiver unit <NUM> and the microphone unit <NUM> are arranged in line with each other, i.e. along the imaginary longitudinal centre line <NUM>.

The nozzle (or spout) <NUM> comprises three portions - a first portion <NUM> comprising a receiver unit mount for housing at least part of the receiver unit <NUM>, a second portion <NUM> comprising a microphone unit mount for housing at least part of the microphone unit <NUM> and a third portion <NUM> connecting the first and second nozzle portions <NUM>, <NUM>. The third nozzle portion <NUM> comprises at least one sound channel adapted to guide generated sound pressure waves from the sound outlet opening <NUM> of the receiver unit <NUM> to at least one sound outlet opening <NUM>, <NUM> of the nozzle <NUM> as indicated by the arrows. Possible implementations of the at least one sound channel within the third nozzle portion <NUM> will be discussed in further details in relation to <FIG> and <FIG>.

The three nozzle portions <NUM>, <NUM>, <NUM> are preferably manufactured as a one-piece structure, such as a moulded one-piece structure.

The second nozzle portion <NUM> comprises a microphone unit mount in the form of an indentation into which a least part of the microphone unit <NUM> is arranged. As depicted in <FIG> the sound inlet opening <NUM> of the microphone unit <NUM> faces, or is oriented towards, the interior of the nozzle <NUM> in order to prevent that ear wax, moisture or other undesired objects block or damage the microphone unit <NUM>. Incoming sound pressure waves thus enter the sound channels <NUM>, <NUM> (free space regions) between the microphone unit <NUM> and the indentation before reaching the sound inlet opening <NUM> as indicated by the two arrows. Electrical signals to and from the microphone unit <NUM> are provided via electrical wires through the third nozzle portion <NUM>.

Retaining members <NUM> may optionally be arranged on an exterior surface of the third nozzle portion <NUM>. Such retaining members <NUM> may be used for securing a positioning member (not shown), such as a dome, to the third nozzle portion <NUM>.

Turning now to <FIG>, two three-dimensional views of an acoustical assembly according to the present invention are depicted. As seen in <FIG>, the receiver unit <NUM> is inserted into the first portion <NUM> of the nozzle, whereas the second portion <NUM> of the nozzle houses the microphone unit <NUM>. A, preferably replaceable, wax protection member <NUM> is secured to the second portion <NUM> of the nozzle. The wax protection member <NUM> is adapted to secure the microphone unit <NUM> to the second portion <NUM> of the nozzle, and protect the microphone unit <NUM> against ear wax.

As seen from the top view of <FIG> the wax protection member <NUM> comprises sound inlet openings <NUM>, <NUM> which are aligned with respective sound channels (not shown) of the second portion <NUM> of the nozzle in order to guide incoming sound pressure waves to a sound inlet opening (not shown) of the microphone unit <NUM>. Returning now to <FIG> the nozzle further comprises a retaining member <NUM> and oppositely arranged sound outlet openings <NUM> (only one opening is visible) for the receiver unit <NUM>. The oppositely arranged sound outlet openings <NUM> are acoustically connected to the sound outlet opening (not shown) of the receiver unit <NUM> via at least one sound channel within the nozzle.

Referring now to <FIG> two side views of the acoustical assembly of <FIG> are depicted. In <FIG> the acoustical assembly is rotated <NUM> degrees around a longitudinal axis compared to <FIG>. Again, the receiver unit <NUM> is inserted into the first portion <NUM> of the nozzle, said nozzle further comprising a retaining member <NUM>, oppositely arranged sound outlet openings <NUM> (only one opening is visible in <FIG>) and a second portion <NUM> for housing the microphone unit <NUM>. Similar to <FIG>, a preferably replaceable wax protection member <NUM> is secured to the second portion <NUM> of the nozzle. <FIG> shows a top view of the acoustical assembly without the wax protection member <NUM>. As seen in <FIG> the microphone unit <NUM> is arranged at least partly in an indentation <NUM> provided in the second portion <NUM> of the nozzle. A small gap <NUM> of free space is provided between the microphone unit <NUM> and the edges of the indentation <NUM>. Moreover, sound channels <NUM>, <NUM> are provided on both sides of the microphone unit <NUM> in order to guide incoming sound pressure waves to a sound inlet opening (not shown) of the microphone unit <NUM>. The sound channels <NUM>, <NUM> are aligned with sound inlet openings <NUM>, <NUM> of the wax protection member <NUM>, cf. A pair of oppositely arranged tracks <NUM>, <NUM> are provided in the second portion <NUM> of the nozzle. These tracks <NUM>, <NUM> are adapted to receive respective resilient leg portions <NUM>, <NUM> of the wax protection member <NUM>. Respective locking arrangements <NUM>, <NUM> are provided at the ends of the legs portions <NUM>, <NUM>. These locking arrangements <NUM>, <NUM> are adapted to engage with corresponding locking arrangements (not shown) provided at the ends of the tracks <NUM>, <NUM> whereby the wax protection member <NUM> clicks onto the second portion <NUM> of the nozzle.

<FIG> depicts a cross-sectional schematic view of an exemplary embodiment <NUM> of the acoustical assembly of the present invention. As depicted in <FIG> this embodiment comprises an in line arrangement of a receiver unit <NUM>, a nozzle <NUM>, <NUM> having two oppositely arranged sound outlet openings <NUM>, <NUM> and a microphone unit <NUM>. Sound pressure waves escaping the sound outlet opening <NUM> of the receiver unit <NUM> are guided to the two oppositely arranged sound outlet openings <NUM>, <NUM> via respective sound channels <NUM>, <NUM> within the nozzle as indicated by the two arrows. The microphone unit <NUM> is at least partly arranged in an indentation <NUM> in the nozzle portion <NUM> with its sound inlet opening <NUM> facing the interior of the nozzle in order to prevent that ear wax, moisture or other undesired objects block the sound inlet opening <NUM> of the microphone unit <NUM> or damages the microphone unit <NUM>. As indicated by the two arrows around the microphone unit <NUM> incoming sound pressure waves are allowed to reach the sound inlet opening <NUM> of the microphone unit <NUM> via a gap between the microphone unit <NUM> and the indentation <NUM>. The embodiment depicted in <FIG> further comprises a preferably soft and/or flexible dome-shaped positioning member <NUM> for positioning the acoustical assembly correctly in the ear canal. The positioning member <NUM> is preferably manufactured of a soft and flexible material, such as silicone, in order to increase comfort for the user while wearing the acoustical assembly. Moreover, a deflection member <NUM> comprising a sound inlet opening <NUM> for the microphone unit <NUM> is provided. As depicted in <FIG> the sound inlet opening <NUM> for the microphone unit <NUM> is arranged on top of the deflection member <NUM> thus facing the ear drum when inserted in an ear canal. The deflection member <NUM> and the positioning member <NUM> preferably form an integral one-piece moulded structure with sound outlet openings aligned with the corresponding sound outlet openings <NUM>, <NUM> of the nozzle.

<FIG> depicts a cross-sectional schematic view of another exemplary embodiment <NUM> of the acoustical assembly of the present invention. Similar to the embodiment of <FIG> this embodiment also comprises an in line arrangement of a receiver unit <NUM>, a nozzle <NUM>, <NUM> and a microphone unit <NUM>. In contrast to the embodiment of <FIG> the embodiment of <FIG> comprises only a single sound outlet opening <NUM>. Again, sound pressure waves escaping the sound outlet opening <NUM> of the receiver unit <NUM> are guided to the sound outlet opening <NUM> via a sound channel <NUM> within the nozzle as indicated by the arrow. The microphone unit <NUM> is at least partly arranged in an indentation <NUM> in the nozzle portion <NUM> with its sound inlet opening <NUM> facing the interior of the nozzle in order to prevent that ear wax, moisture or other undesired objects block the sound inlet opening <NUM> of the microphone unit <NUM> or damages the microphone unit <NUM>. As indicated by the arrow to the right of the microphone unit <NUM> incoming sound pressure waves are allowed to reach the sound inlet opening <NUM> of the microphone unit <NUM> via a passage in or beneath the deflection member <NUM> and a gap between the microphone unit <NUM> and the indentation <NUM>. Similar to the embodiment shown in <FIG> the embodiment depicted in <FIG> also comprises a preferably soft and flexible dome-shaped positioning member <NUM> for positioning the acoustical assembly correctly in the ear canal. The positioning member <NUM> is preferably manufactured of a flexible material, such as silicone, thus increasing the comfort for the user during use. A deflection member <NUM> is also provided. As depicted in <FIG> a sound inlet opening <NUM> for the microphone unit <NUM> is provided in or beneath the deflection member <NUM> as indicated by the arrow. The deflection member <NUM> and the positioning member <NUM> preferably form an integral one-piece moulded structure with a sound outlet opening aligned with the opening <NUM> of the nozzle.

The acoustical assembly of the present invention preferably forms part of a hearing device, i.e. hearing aids/hearables earbuds and the like, to be inserted into the ear canal of the user. The overall dimensions and shape of the acoustical assembly are thus limited in order to comply with such space limited applications.

Claim 1:
An acoustical assembly (<NUM>) adapted to be inserted into an ear canal, said acoustical assembly (<NUM>) comprising
- a receiver unit (<NUM>) adapted to generate sound pressure waves,
- a microphone unit (<NUM>) adapted to detect sound pressure waves inside the ear canal when the acoustical assembly (<NUM>) is inserted in the ear canal, and
- a nozzle (<NUM>) comprising a receiver unit mount (<NUM>) adapted to house at least part of the receiver unit (<NUM>), wherein the nozzle (<NUM>) comprises at least one sound channel adapted to guide generated sound pressure waves from a receiver unit outlet opening (<NUM>) to at least one sound outlet opening (<NUM>, <NUM>) of the nozzle (<NUM>),
wherein
the nozzle (<NUM>) further comprises a microphone unit mount (<NUM>) adapted to house at least part of the microphone unit (<NUM>), characterised in that the microphone unit (<NUM>) is arranged in the microphone unit mount (<NUM>) in such a way that a sound inlet opening (<NUM>) of the microphone unit (<NUM>) is not oriented towards the ear drum when the acoustical assembly is inserted in the ear canal.