Description

"INTRA-AURICOLAR INSERT"

The present finding refers to the technical sector of intra-auricular devices and in particular regards an intra-auricular insert as defined in the preamble of the first claim.

As is known, auricular devices of various type, such as for example intra-auricular hearing aids, retro- auricular hearing aids, hearing protector devices and electro-acoustic auricular devices include or consist of an intra-auricular insert, i.e. an insert having an essentially counter-shaped body with respect to a portion of the external auditory canal of a human being and intended to be received in a removable manner inside such canal .

As is known, the presence of such insert inside the auditory canal produces numerous drawbacks, such as for example irritation due to the presence of a foreign body inside the auditory canal, a sensation of occlusion, the so-called autophony phenomenon and over the long term the atrophying of the auditory canal.

For example, in the retro-auricular hearing aids of classic type (i.e. not of so-called "open" type), and in the intra-auricular hearing aids, in the presence of an insert inside an auditory canal, the voice of the person

wearing the insert and the sounds of the body transported by the tissues produce vibrations of the auditory canal's soft walls. This generates a sound which, remaining trapped in the insert-occluded auditory canal, causes an increase of the sound pressure on the wall of the eardrum, thus giving rise to an unpleasant sensation of occlusion. Moreover, in the retro-auricular hearing aids of classic type (i.e. not of so-called "open" type), in the presence of an insert inside the auditory canal, still causing the occlusion of the auditory canal, the so-called autophony phenomenon is observed, due to which the wearer of the aid perceives his own voice to be unnatural, booming, deep and with an echo effect.

To at least partly overcome such drawbacks, in numerous applications it is necessary to make a ventilation channel along the intra-auricular insert, for example a rectilinear channel which crosses inside the body of the intra-auricular insert, placing the inner part of the auditory canal in fluid communication with the outside environment when the intra-auricular insert is applied to the auditory canal.

Nevertheless, it has been seen that the presence of a ventilation channel, in hearing aids and above all in aids of intra-auricular type, triggers a feedback phenomenon, the Larsen effect, which produces an annoying

whistle. This phenomenon is more accentuated the greater the section of the ventilation channel.

The object of the present finding is that of making available an intra-auricular insert capable of overcoming the drawbacks of the above-described inserts of the prior art .

Such object is attained by means of an intra- auricular insert as defined in the attached first claim in its most general form and in the dependent claims in particular embodiments thereof.

The finding will be better understood from the following detained description of several embodiments thereof, made as exemplifying and therefore in no manner limiting with regard to the drawing represented in figure 1, which shows a three-dimensional schematic view of a particularly preferred intra-auricular insert 1 embodiment in accordance with the present finding.

The intra-auricular insert 1 can be received in an external auditory canal of an individual and has a main body 2 essentially counter-shaped with respect to a portion of such auditory canal. The main body 2, for example made of silicon or of other appropriate materials for making an intra-auricular insert, is preferably but not exclusively custom-made based on the individual's auditory canal, inside of which the body 2 is intended to

be received. The custom-manufacture can for example be carried out by taking a physical mould of the individual's auditory canal or through measurements of opto-electronic type, according to techniques known to a man skilled in the art and for this reason not discussed here in further detail.

In the particular represented example, the main body 2 of the intra-auricular insert 1 is, as a non-limiting example, in the form of a tubular shell intended to receive in an inner cavity possible electronic and electro-acoustic components, so to form a hearing aid of intra-auricular type. In an alternative embodiment, the intra-auricular insert 1 could for example represent the intra-auricular part of a retro-auricular hearing aid, and therefore does not contain electronic or electro- acoustic devices. In a further embodiment, the intra- auricular insert 1 could be a simple hearing protector. In the latter case, the main body 2 would be an essentially solid body lacking the inner cavity 6. In a further embodiment, the intra-auricular insert 1 could be the intra-auricular part or the external shell thereof of an electro-acoustic auricular device, such as for example an auricular device for listening to music and voice or an auricular device for a mobile communication terminal, such as for example a personal communication terminal.

The main body 2 is extended along an insert axis A- A, B-B between an inner end portion 3 of the body, i.e. intended to be turned towards the interior of the auditory canal, and an outer end portion 4 of the body 2, i.e. intended to be turned towards the outside of the auditory canal. In a particularly preferred embodiment, the insert axis A-A, B-B can be approximated as a bent line formed by two lines A-A, B-B which intersect in a point . The main body 2 of the insert 1 comprises a annular wall 5 around the A-A, B-B axis of the insert 1, provided with a recess preferably having an approximate depth in the range of 0.75 mm - 1.5 mm and more preferably approximately in the range of 1 mm - 1.25 mm which continuously extends substantially between the end portions 3, 4 so to make, by cooperating with a surface of the auditory canal, a ventilation channel A-A, B-B.

It must be observed that the wall 5, being substantially counter-shaped with respect to human auditory channels, may have sections which are not limited to be circular around the axis of the insert. For example such sections can be also oval sections or elliptic sections.

According to the finding, the ventilation channel comprises a plurality of axially-spaced curved sections

Cl, C2, C3, each of which at least partially surrounds the axis A-A, B-B. The ventilation channel moreover comprises at least one transverse section T2, T3 which places two consecutive curved sections in fluid communication.

In the particularly preferred embodiment represented in figure 1, the ventilation channel comprises three curved sections Cl, C2, C3 and two transverse connection sections T2, T3 in which the curved sections Cl and C2 are placed in communication by the transverse connection section T2 and in which the curved sections C2 and C3 are placed in communication by the transverse connection section T3. The ventilation channel moreover includes two terminal transverse sections Tl, T4 respectively in communication with the curved section Cl and the curved section C3 and which constitute two opposite end portions of the ventilation channel. In an alternative embodiment, for example related to the case in which the insert 1 is intended to be applied to the auditory canal of a child, this being therefore an auditory channel with reduced length with respect to an adult's auditory canal, the ventilation channel could be composed of two single curved sections and by three transverse sections, including a intermediate section suitable for placing the two curved sections in communication with each other and

the remaining two constituting two opposite end portions of the ventilation channel.

In a preferred embodiment, the curved sections Cl,

C2, C3 are preferably each composed of an annular recess which completely surrounds the axis A-A, B-B of the insert 1. Alternatively, the curved sections Cl, C2, C3, each consist of only one ring portion.

In the particular preferred embodiment of figure 1, the transverse sections T1-T4 are rectilinear sections. In an alternative embodiment, the transverse sections Tl- T4 could be curvilinear sections.

In practice, it is observed that an insert in accordance with the present finding has a ventilation channel which defines one or more acoustic paths with non-planar and irregular serpentine-like shape.

In a particularly preferred embodiment, the ventilation channel is conformed so that two consecutive intermediate/terminal transverse sections, i.e. two transverse sections of any type directly in communication with a same curved section, are arranged on substantially opposite portions of the wall 4 with respect to the axis of the intra-auricular insert 1, the opposite wall 4 portions also being axially spaced.

As represented in figure 1 in a particularly advantageous embodiment, the wall 4 on the side opposite

each intermediate or terminal transverse section has wall portions with convex profile. It can be observed in fact in figure 1 how the wall 4 has a convexity El opposite the transverse section Tl, a convexity E2 opposite the transverse section T2, a convexity E3 opposite the transverse section T3 and a convexity E4 (the latter little visible in the figure) opposite the transverse section T4.

Based on laboratory tests, it has been observed that an insert according to the present finding is capable of fully attaining the pre-established aims. It was in fact observed that when the insert is employed in a hearing aid, the particular form of the ventilation channel tends to considerably diminish the rise of the Larsen effect, due to the numerous discontinuities which a feedback acoustic signal encounters when travelling through the ventilation channel. In an aid in accordance with the present invention, the ventilation channel can therefore have a greater section with respect to the channel sections of the inserts of the prior art, considerably increasing the auditory comfort of the wearer of such aid.

Moreover, it has been observed that the particular embodiment in which the wall has the convexities El, E2, E3, E4 permits having a discontinuous support of the

insert on the skin of the auditory canal, significantly reducing the risk of atrophies and thus also the risk of an undesired exit of the intra-auricular insert from the canal . Moreover, it was observed that the particular shape of the ventilation channel considerably increases the comfort of the insert 1 wearer, even when the insert is a simple hearing protection device or is the intra- auricular part of an auricular device for the diffusion of sound and/or voice inside the auditory canal, or it is the intra-auricular part of an auricular device of a personal communication terminal.

Of course, a man skilled in the art, in order to satisfy contingent and specific needs, can make numerous modifications and variants to the above-described insert, all moreover contained in the protective scope as defined by the following claims.