Patent Description:
Hearing protection devices are often used in, for example, industrial, military, and recreational applications.

<CIT> describes a protective earplug comprising: first passage means arranged for positioning with at least an inner end portion thereof in an ear canal to define a first sound passage extending from an inner end within the ear canal to an opposite outer end, a relative large acoustic resistance means arranged for cooperation with an intrinsic acoustic mass reactance of said first passage and an intrinsic acoustic compliance of the ear canal to provide a substantially non-resonant acoustic impedance, and second passage means defining a second sound passage having an inner end coupled to said outer end of said first passage and having an opposite sound-receiving outer end, said second passage being operative to increase response characteristics at frequencies in an audible spectrum above approximately <NUM>.

In broad summary, herein is disclosed an earpiece body comprising a convoluted acoustic horn as defined in claim <NUM>; and, a hearing protection device as well as a kit that includes such an earpiece body as defined in claims <NUM> and <NUM>, respectively. These and other aspects will be apparent from the detailed description below.

Like reference numbers in the various figures indicate like elements. Some elements may be present in identical or equivalent multiples; in such cases only one or more representative elements may be designated by a reference number but it will be understood that such reference numbers apply to all such identical elements. Unless otherwise indicated, all figures and drawings in this document are not to scale and are chosen for the purpose of illustrating different aspects of the invention. In particular the dimensions of the various components are depicted in illustrative terms only, and no relationship between the dimensions of the various components should be inferred from the drawings, unless so indicated.

For clarity of description of the device disclosed herein and its placement and functioning in a human ear, the following terminology will be adhered to. (Many descriptions presented herein are with respect to a human right ear as viewed in the Figures and to a device fitted therein; it will be understood that corresponding descriptions apply to a human left ear and to a like device fitted therein. ) As used herein, "inward" means toward the inner ear of the ear that the device is fitted in; "outward" means away from the inner ear of the ear that the device is fitted in. An inward-outward axis IOa (as seen e.g. in <FIG>, <FIG> and <FIG>) of an earpiece body means an axis that is oriented at least generally along this direction when the body is fitted into the ear of a user. "Radially inward" and "radially outward" respectively mean radially inward toward, and radially outward away from, this axis (e.g., in a direction at least generally orthogonal to this axis). The terms clockwise and counterclockwise have their customary meaning. Terms such as upper, upward, top, above, and the like; and lower, downward, bottom, below, and the like; have their customary meaning with reference to an axis that runs generally up and down along the human ear (e.g., an earlobe is at the bottom of the human ear).

As used herein as a modifier to a property or attribute, the term "generally", unless otherwise specifically defined, means that the property or attribute would be readily recognizable by a person of ordinary skill but without requiring a high degree of approximation (e.g., within +/- <NUM> % for quantifiable properties). The term "substantially", unless otherwise specifically defined, means to a high degree of approximation (e.g., within +/- <NUM>% for quantifiable properties). The term "essentially" means to a very high degree of approximation (e.g., within plus or minus <NUM> % for quantifiable properties); it will be understood that the phrase "at least essentially" subsumes the specific case of an "exact" match. However, even an "exact" match, or any other characterization using terms such as e.g. same, equal, identical, uniform, constant, and the like, will be understood to be within the usual tolerances or measuring error applicable to the particular circumstance rather than requiring absolute precision or a perfect match. All references herein to numerical parameters (dimensions, ratios, and so on) are understood to be calculable (unless otherwise noted) by the use of average values derived from a number of measurements of the parameter, particularly for the case of a parameter that is variable.

As shown in exemplary device in <FIG>, disclosed herein is a hearing protection device <NUM> that is suitable for fitting into the concha of a human ear. In at least some cases, device <NUM> is a passive device, which will be distinguished from an electronic hearing protection device. As shown in <FIG>, device <NUM> is comprised of two major components - eartip <NUM> and earpiece body <NUM>. Earpiece body <NUM> is configured (i.e., shaped and sized) to reside in the concha of a human user's ear and is configured to receive airborne sound which passes into, and through, a convoluted acoustic horn <NUM> (most easily seen in <FIG>), and is then emitted therefrom to be received by eartip <NUM>. Eartip <NUM> is configured (i.e., is shaped and sized and is comprised of a material of suitable softness) to fit into the ear canal of the user's ear (this terminology broadly denotes that at least a portion of eartip <NUM> fits into an outward portion of the ear canal and does not imply that the entirety of eartip <NUM> must be fitted into the ear canal). In at least some examples eartip <NUM> is detachably attached to earpiece body <NUM> so that eartip <NUM> can be removed and cleaned or replaced if desired. In other examples eartip <NUM> may be supplied along with earpiece body <NUM>, e.g. non-detachably attached thereto.

An exemplary earpiece body <NUM> is shown in <FIG> (in combination with an eartip <NUM>) and in isolated view in <FIG>. Earpiece body <NUM> comprises a housing <NUM> which may be comprised of e.g. a molded polymeric material. In some examples, housing <NUM> may be formed by mating together two major housing parts, e.g. inward and outward major housing parts. In other examples, housing <NUM> (and e.g. the entirety of earpiece body <NUM>) may be comprised of a single entity, made e.g. by 3D printing. Housing <NUM> at least partially defines an interior <NUM> (seen e.g. in <FIG>), within which is provided convoluted acoustic horn <NUM>, described in detail later herein. It is emphasized that the cross-sectional view of <FIG> is merely an idealized representation in which most portions of earpiece body interior <NUM> other than acoustic horn <NUM> are depicted as solid. This is done for ease of visualizing acoustic horn <NUM>; in many cases interior <NUM> of earpiece body <NUM> may comprise one or more void spaces in addition to the void spaces that collectively provide acoustic horn <NUM>. Such additional void spaces may e.g. provide room for other components or features as discussed later herein.

In at least some examples, housing <NUM> may be comprised of a rigid or semi-rigid material, e.g., a material that is not as soft and deformable as the material of eartip <NUM>. In various examples, housing <NUM> may be comprised of an organic polymeric material (e.g., a thermoplastic injection-molding resin) with a hardness of at least about <NUM>, <NUM>, <NUM> or <NUM> on a Shore A scale.

Earpiece body <NUM> comprises an acoustic horn <NUM>, as seen in exemplary earpiece body in <FIG>. By definition an acoustic horn comprises a first, sound-receiving opening <NUM> (i.e., an entrance) and a second, sound-emitting opening <NUM> (i.e., an exit, as seen e.g. in <FIG>) that are fluidly connected with each other so that airborne sound that enters the entrance can travel through the horn to be emitted from the exit. By definition, sound-receiving entrance <NUM> is larger in area than sound-emitting exit <NUM>, so that entrance <NUM> functions as a "mouth" of the horn while exit <NUM> functions as a "throat" of the horn.

In some cases, sound-receiving entrance <NUM> is an at least generally outward-facing opening (as evident e.g. in <FIG> and <FIG>, and particularly in <FIG>), meaning that it faces at least generally outward along the inward-outward axis IOa of earpiece body <NUM>. In other cases, sound-receiving entrance <NUM> may be an at least generally inward-facing opening. In at least some examples, sound-emitting exit <NUM> is an at least generally inward-facing opening (noting that in the exemplary earpiece body of <FIG>, exit <NUM> is generally inward-facing albeit at a slight angle away from the inward-outward axis IOa).

Acoustic horn <NUM> is a convoluted horn with the term convoluted having its ordinary meaning; i.e., horn <NUM> follows a path (along the length of the horn from entrance <NUM> to exit <NUM>) that is at least e.g. generally tortuous, serpentine, coiled or spiral. Such a convoluted horn (as seen most easily in the exemplary earpiece body of <FIG>) is distinguished from e.g. a "hairpin" horn that, along its length, comprises only a single, sharply-bending portion with the remainder of the horn length being relatively straight.

In some examples, acoustic horn <NUM> may be a helical horn, meaning that at least a significant portion (meaning at least about <NUM> percent) of the length of horn <NUM> exhibits a helical path that moves in an inward direction in traversing the length of the horn from entrance <NUM> to exit <NUM>. Such a helical horn path is distinguished from an at least substantially flat-spiral path in which most or essentially all of the path is in a plane that is at a relatively constant location along the IOa axis. In further embodiments in which acoustic horn <NUM> is a helical horn, at least <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> percent of the path length of the horn exhibits a helical path.

For the purpose of measuring a path length (or any other characterization of horn <NUM>), the "path" of horn <NUM> is traced along the centerline of horn <NUM> from entrance <NUM> to exit <NUM>. (As discussed later in detail and as evident e.g. in <FIG>, exit <NUM> of horn <NUM> does not necessarily have to be the same opening as the sound-emitting opening (<NUM> in <FIG>) through which airborne sound leaves earpiece body <NUM>. ) For the simple case of a horn in which the cross-sectional area of the horn is circular along the length of the horn, such a path would simply be a centerline trace that followed the horn from entrance to exit, connecting the geometric centers of each successive circular cross-section down the length of the horn. For other shapes (e.g., squares, rectangles, isosceles triangles and the like) such a path would similarly follow the geometric center of each successive cross-section along the length of the horn. For e.g. irregular shapes, non-isosceles triangles, and so on, the centroid (barycenter) of each successive cross-sectional slice of the horn can be used to establish the path. If a horn varies in cross-sectional shape along its length, any of these may be used in combination as needed.

In some examples, acoustic horn <NUM> may exhibit at least one underpass feature. An underpass feature is one in which, when the horn is viewed from the outward side looking inward along the inward-outward axis IOa as in <FIG>), at least a portion of a cross-sectional area of an inward portion of the horn inwardly underlies at least a portion of a cross-sectional area of an outward portion of the horn (and is separated therefrom by some volume of interior <NUM> of earpiece body <NUM> that is not part of the acoustic horn). That is, when viewed in this manner, such an inward portion of the horn at least partially passes inwardly under the outward portion of the horn. Two such underpass features <NUM> and <NUM> are visible in <FIG> and <FIG>, and particularly in <FIG>. In various examples, acoustic horn <NUM> may have none, one, two, three, four, or more underpass features.

Second, sound-emitting opening (exit) <NUM> of convoluted horn <NUM> is an offset opening. By this is mean that when viewed along inward-outward axis IOa of the earpiece body, opening (exit) <NUM> of horn <NUM> does not overlap the geometric center (centroid) of earpiece body <NUM>. The view (along the inward-outward axis) of <FIG> thus reveals that exemplary exit <NUM> as shown therein is an offset opening. It will be appreciated that a horn exit that is offset in this manner (as opposed to e.g. a horn exit located substantially in the geometric center of an earpiece body) may advantageously allow a larger earpiece body (and thus a larger and/or longer horn) to be used without some portion of the earpiece body impinging on some portion (e.g. the tragus and/or antitragus) of the user's ear, which might cause discomfort.

In some cases, first, sound-emitting opening (entrance) <NUM> of convoluted horn <NUM> may be an offset opening. By this is mean that when viewed along inward-outward axis IOa of the earpiece body, opening (entrance) <NUM> of horn <NUM> does not overlap the geometric center (centroid) of earpiece body <NUM>. In some cases, entrance <NUM> and exit <NUM> are arranged so that horn <NUM> takes the form of an offset spiral. By this is meant that (again when viewed along the inward-outward axis) no portion of exit <NUM> overlaps with any portion of entrance <NUM>. The view of <FIG> thus reveals that exemplary horn <NUM> as shown therein is in the form of an offset spiral.

In some cases, acoustic horn <NUM> may take the form of an eccentric spiral when viewed along an inward-outward axis of the earpiece body. By eccentric is meant that the spacing between concentrically neighboring segments (as measured between the above-discussed centerlines of the segments) of the horn is not constant. The exemplary horn of <FIG> is thus seen to take the form of an eccentric, and offset, spiral. It will be appreciated that such arrangements may e.g. advantageously allow room in interior <NUM> of earpiece body <NUM> for internal components, mechanisms and the like (for example, components associated with a valve <NUM> as discussed later herein). In some cases, horn <NUM>, when viewed along an inward-outward axis of the earpiece body, may (as ascertained by following the above-described centerline path of the horn) make at least <NUM>, <NUM>, <NUM>. <NUM>, or <NUM> revolutions along the length between entrance <NUM> and exit <NUM>. In further cases, horn <NUM> may make less than <NUM>, <NUM>, or <NUM> revolutions along this length (the exemplary horn of <FIG> appears to make approximately <NUM> revolutions).

The ordinary artisan will appreciate that acoustic horn <NUM> may advantageously allow airborne sound of at least certain frequencies to be received (gathered) by entrance <NUM> and transmitted down the length of horn <NUM> to leave horn <NUM> through exit <NUM>. The decreasing cross-sectional area of horn <NUM> will provide that the sound waves increase in intensity during the journey down horn <NUM>. The providing of an acoustic horn <NUM> in an earpiece body can thus, for at least certain frequencies, at least partially offset the insertion loss that often occurs when an earpiece body is inserted into the concha thus disrupting the natural sound-gathering effect of the external ear.

The horn effect is thus achieved by providing that horn entrance <NUM> is larger than horn exit <NUM>. The first, sound-receiving opening is larger in cross-sectional area than the second, sound-emitting opening by an incremental percentage of from <NUM> to <NUM>. In various examples, the area of the first, sound-receiving opening (entrance) <NUM> may be greater than the area of the second, sound-emitting opening by an incremental percentage of from <NUM> to about <NUM>. In further examples, the area of the entrance may be greater than that of the exit by an incremental percentage of about <NUM> to about <NUM>, or about <NUM> to about <NUM>. The incremental percentage is calculated using the smaller, exit opening as a basis. For example, given an opening with an area of <NUM><NUM> and an exit with an area of <NUM><NUM>, the opening would be greater in area than the exit by an incremental percentage of (<NUM> - <NUM>)/<NUM> or about <NUM>. (Strictly speaking, the area of entrance <NUM> as used in such calculations will be the effective area, exclusive of any area obstructed by solid materials of e.g. a mesh or screen that is not acoustically transparent at the sound frequencies of interest, as discussed later in detail).

In various examples, the area of horn entrance <NUM> may be at least about <NUM>, <NUM>, or <NUM><NUM>. In further examples, the area of horn entrance <NUM> may be at most about <NUM>, <NUM>, or <NUM><NUM>. In various examples, the area of horn exit <NUM> may be at least about <NUM>, <NUM>, or <NUM><NUM>. In further examples, the area of horn exit <NUM> may be at most about <NUM>, <NUM>, or <NUM><NUM>. In various examples, the length of horn <NUM> from entrance <NUM> to exit <NUM> may be at least about <NUM>, <NUM>, <NUM>, or <NUM>. In further examples, the length of horn <NUM> may be at most about <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>.

The fact that exit <NUM> is smaller in area than entrance <NUM> will result in horn <NUM> exhibiting a taper. In various cases, horn <NUM> may exhibit an overall taper (measured over the entire horn length) that is at least about <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> incremental percentage per centimeter of horn length. In further cases, horn <NUM> may exhibit an overall taper that is at most about <NUM>, <NUM>, <NUM>, or <NUM> incremental percentage per centimeter of horn length. By way of specific example, a horn with an entrance of <NUM><NUM> in area and an exit area of <NUM><NUM> in area, and with a length of <NUM>, would exhibit an incremental taper of ([<NUM> - <NUM>]/<NUM>) / <NUM>, or about <NUM> incremental percentage per cm of horn length. The local taper at any particular point along the length of horn <NUM> may vary from the overall taper, or course. That is, in some cases the taper may be more pronounced at some locations, and less pronounced at other locations. One exemplary version of this would be a design in which horn <NUM> exhibits a few (e.g., four, three, two, or even one) step changes in area over the length of horn <NUM>. While such designs are within the scope of an acoustic horn as disclosed herein, in other designs horn <NUM> may exhibit an at least substantially constant taper, meaning that the local taper is within plus or minus <NUM> % of the overall average taper, over at least a substantial portion (i.e., <NUM> %) of the path length. In this context, a constant taper does not include the particular case of a zero or near-zero (i.e., less than <NUM> incremental percentage per cm of horn length) taper. In particular embodiments, horn <NUM> is smoothly-tapered, meaning that as the length of horn <NUM> is traversed from entrance <NUM> to exit <NUM>, the area of the horn does not increase at any point along the length of the horn. While it may be convenient that horn <NUM> have an at least generally circular shape at any or all locations along the length of horn <NUM>, the shape is not particularly limited and, at any given location along its length, horn <NUM> may have any suitable shape (e.g., square, rectangular, oval, triangular, irregular, and so on). In various examples, horn <NUM> may have a shape corresponding at least generally, substantially, or essentially, to a conical horn, an exponential horn, or a tractrix horn.

In at least some cases, entrance <NUM> and exit <NUM> are the only openings (by which airborne sound waves can enter or exit horn <NUM>) in horn <NUM>. Horn exit <NUM> by definition is the inward end of horn <NUM>. As noted elsewhere herein, horn exit <NUM> may not necessarily correspond to an inwardmost and/or terminal opening of earpiece body <NUM> (for example, in the exemplary design shown in <FIG>, horn exit <NUM> is distinguished from sound-emitting outlet <NUM> of earpiece body <NUM>, outlet <NUM> being located at an inwardmost location of earpiece body <NUM>).

In some cases, horn entrance <NUM> may be a substantially unobstructed opening, meaning that no more than <NUM> % of the potentially available area of the opening is obstructed by an air-impermeable material (e.g., by solid portions of a screen, mesh, perforated plate, or the like, or by some other item). In further cases, horn entrance <NUM> is an unobstructed opening, meaning that no portion of the potentially available area of the opening is obstructed by an air-impermeable material. In the exemplary earpiece body shown in <FIG> and <FIG>, entrance <NUM> is an unobstructed opening, since no portion of the total potentially available area (i.e., the area bounded by the circular rim that defines opening <NUM>) is obstructed. Such configurations can be contrasted with e.g. designs in which a significant portion, or even a majority, of the potentially available area of an opening is obstructed. A particular example of an obstructed opening would be an opening in which a cylindrical member is positioned within much of the opening so that the usable area of the opening that is available for collecting sound waves, is an annulus that has a much lower area than would have been available had the entire area of the opening been used.

It will be appreciated that a convoluted horn design as disclosed herein can allow a relatively long horn length to be achieved even with an earpiece body that is relatively unobtrusive in size and appearance and in particular is relatively low-profile (e.g., does not protrude significantly out of the concha). This relatively long horn length, in combination with a taper as disclosed herein, can provide that acoustic horn <NUM> exhibits a cutoff frequency (below which little or no sound may be effectively gathered and/or intensified) in the range of about <NUM>. This can provide that acoustic horn <NUM> can selectively amplify sound in wavelength ranges that are most useful e.g. for human speech intelligibility; that is, sound in the range of e.g. <NUM> and above. (Strictly speaking, horn <NUM> may not be considered as "amplifying" such sound over what would be heard in the absence of earpiece body <NUM> being present in the user's ear; rather, horn <NUM> is helping to compensate for the insertion loss that occurs upon the placement of earpiece body in the ear thus disrupting the external ear's natural sound-gathering and collecting ability).

In particular cases, using a level-dependent sound-attenuating feature (e.g., a level-dependent acoustic filter as discussed later herein) in combination with horn <NUM> in a hearing protection device <NUM>, can provide that device <NUM> can allow enhanced human speech intelligibility, while still allowing device <NUM> to adequately protect the user from loud sounds. Also as noted later herein, in further cases, providing a valve at some location along the complete acoustic pathway through device <NUM> can, if desired, allow device <NUM> to be reversibly converted into a "closed" earplug (e.g. if the user is in an environment in which relatively high-intensity sound is frequently or constantly present and thus in which the highest possible sound-blocking is desired).

Earpiece body <NUM> comprises an at least generally inward-facing, airborne-sound-emitting outlet <NUM> (most easily seen in <FIG> and <FIG>) that may be conveniently provided in a location which allows a primary, sound-receiving opening <NUM> of through-passage <NUM> of eartip <NUM> to be acoustically mated thereto. By "acoustically mated" is meant that outlet <NUM> of earpiece body <NUM> and the primary, sound-receiving opening <NUM> of eartip <NUM> are fluidly connected with each other so that sound waves emitted from outlet <NUM> are able to travel (e.g., directly) therefrom into opening <NUM>. In an exemplary configuration most easily seen in <FIG> and <FIG>, outlet <NUM> may be provided proximate the terminal end of a hollow protrusion <NUM> (e.g., post) that extends inward (when device <NUM> is fitted into a user's ear), so that when outward end <NUM> of eartip <NUM> is attached to protrusion <NUM>, outlet <NUM> of earpiece body <NUM> and opening <NUM> of eartip <NUM> are aligned with each other and in close proximity to each other. (In many cases outward end <NUM> of eartip <NUM> may be pushed onto protrusion <NUM> e.g. to provide a secure connection via a compression fit, so that strictly speaking, the opening <NUM> of eartip <NUM> that receives the sound emitted from outlet <NUM>, may be located somewhat inward along through-passage <NUM> of eartip <NUM> rather than being at the outward terminus of through-passage <NUM>). In some cases, protrusion <NUM> of earpiece body <NUM> may be of the same composition and properties (e.g., made of the same material) as housing <NUM> of earpiece body <NUM>. In particular embodiments, protrusion <NUM> may be an integral portion of housing <NUM> (which condition encompasses the case that protrusion <NUM> is an integral portion of a major housing part, in the specific instance that housing <NUM> is formed by the mating together of two major housing parts).

In some cases, eartip <NUM> may be attached to earpiece body <NUM> (e.g., outward end <NUM> of eartip is attached to protrusion <NUM> of earpiece body <NUM>) in a detachable manner. By this is meant that a user can manually (i.e., with fingers alone, without the use of any special tools such as pliers, screwdrivers, pry bars, and so on) separate eartip <NUM> from earpiece body <NUM> so as to e.g. clean eartip <NUM>, replace it with a new or cleaned eartip, and so on. In the particular device shown in <FIG>, detachable attachment of eartip <NUM> to earpiece body <NUM> may be provided by a friction fit of an annular portion of main body <NUM> of eartip onto the radially outer surface of protrusion (post) <NUM>. (Here and elsewhere, the term annular is used broadly and does not imply or require a strictly or even substantially circular geometry). It will be appreciated however that any suitable method of detachably attaching eartip <NUM> to earpiece body <NUM> can be used.

In at least some cases, device <NUM> may include at least one level-dependent sound- attenuating physical (i.e., non-electronic) feature <NUM>. Such a feature will, at least at some frequencies, attenuate high-intensity sound more than it will attenuate low-intensity sound. Such a feature may take the form of e.g. one or more orifices, restrictions, or obstructions at some location along the length of a sound-transmissive elongate passage, which feature provides a significantly reduced cross-sectional area for passage of sound therethrough, when compared to the average diameter of the passage <NUM>. Such a level-dependent sound-attenuating feature may be located in any suitable sound-transmissive passage, e.g. at any point along the length of acoustic horn <NUM>, or at any point along the length of through-passage <NUM> of eartip <NUM>. However, in particular cases, it may be advantageous to locate such a feature <NUM> between the second, sound-emitting opening (exit) <NUM> of acoustic horn <NUM> and the primary, sound-receiving opening <NUM> of the eartip so that any airborne sound that is emitted from exit <NUM> of the acoustic horn must encounter the sound-level-dependent sound attenuating physical feature before reaching the primary, sound-receiving opening <NUM> of the eartip. Such an arrangement is shown in exemplary earpiece body in <FIG>. In the exemplary design of <FIG>, the sound-level-dependent sound attenuating physical feature is a level-dependent acoustic filter <NUM> that is fitted into a chamber <NUM> defined at least partially by surfaces molded into the interior of protruding post <NUM> of earpiece body <NUM>. In configurations of this general type, airborne sound that is emitted from the second, sound-emitting opening <NUM> of acoustic horn <NUM> must pass through acoustic filter <NUM> in order to exit earpiece body <NUM> (via outlet <NUM>) to reach primary, sound-receiving opening <NUM> of eartip <NUM>.

Any suitable level-dependent acoustic filter may be used. Various potentially suitable acoustic filters are described in detail e.g. in <CIT>, <CIT>, <CIT>, and <CIT>, and in <CIT>. In the specific earpiece body depicted in <FIG>, acoustic filter <NUM> is a hollow, generally drum-shaped entity with a relatively small-diameter aperture at at least one end thereof, that is fitted (e.g. compression-fitted, and/or held by adhesive or any other means) into chamber <NUM>.

In specific examples, a level-dependent sound-attenuating physical feature (e.g., an acoustic filter) located at the above-described position is the only such feature that is present in device <NUM>. That is, in some cases no level-dependent sound attenuating physical feature or features are present in passage <NUM> of eartip <NUM>. For example, in some cases passage <NUM> might be e.g. a hollow conduit with an average diameter (or equivalent diameter) that does not vary by more than e.g. plus or minus <NUM> % along its length. Similarly, in some cases no such level-dependent sound attenuating physical feature or features are located anywhere along the length of acoustic horn <NUM>.

The ordinary artisan will understand that in the exemplary design shown in <FIG>, the above-described exit <NUM> represents the inward end of acoustic horn <NUM>; chamber <NUM> and acoustic filter <NUM> therein are not part of acoustic horn <NUM> (nor is passage <NUM> of eartip <NUM>). The ordinary artisan will further understand that such an arrangement is distinguished from designs in which an acoustic filter/damper is apparently placed at some location within the length of an acoustic horn (e.g., between halfway and two-thirds along the length of the horn). The ordinary artisan will appreciate that locating an acoustic filter/damper within the length of an acoustic horn may disadvantageously affect the functioning of the horn (and in fact might effectively divide the horn into two separate horns in series, with disadvantageous results). The ordinary artisan will thus understand that locating any such level-dependent sound-attenuating physical feature (e.g. an acoustic filter) as disclosed herein may advantageously allow acoustic horn <NUM> to be used to maximum effectiveness.

If desired, earpiece body <NUM> may comprise at least one valve <NUM> that may be actuated to partially or completely close acoustic horn <NUM> so that no airborne sound may be transmitted therethrough. Such a valve may be of any suitable type (e.g. a gate valve comprising a member that can open or close by sliding, bending, and/or partially rotating about a pivot (e.g. hinge). Such a valve may be located at any position along the length of acoustic horn <NUM>. In some examples, such a valve may be located proximate the second, sound-emitting opening (exit) <NUM> of acoustic horn <NUM> (as in the exemplary depiction of <FIG>).

Valve <NUM> may be actuated e.g. by a mechanical switch <NUM> of any suitable type (e.g., a rocker switch, a sliding switch, a rotatable switch, a button switch, and so on). Such a mechanical switch may be in any suitable location of housing <NUM> of earpiece body <NUM>. In some embodiments, switch <NUM> may be conveniently located on outward surface <NUM> of earpiece body <NUM>, so that it may be operated without necessarily having to remove device <NUM> from the ear. In particular cases, valve <NUM> may be located proximate second, sound-emitting opening <NUM> of acoustic horn <NUM>, while switch <NUM> is located on outward surface <NUM> of earpiece body <NUM> (that is, in a location that is remote from valve <NUM>). In such embodiments, switch <NUM> and valve <NUM> may be operatively coupled to each other e.g. by way of one or more pushrods, cables, or the like, in order to facilitate operation of valve <NUM> by switch <NUM>. It will be appreciated that the convoluted design of acoustic horn <NUM>, e.g. in combination with the providing of additional void spaces within interior <NUM> of earpiece body <NUM>, may advantageously facilitate such arrangements.

In general, housing <NUM> of earpiece body <NUM> can be configured so as to minimize (e.g., at least substantially prevent) the entry of ambient airborne sound into interior <NUM> of earpiece body <NUM> except through the desired pathway provided by acoustic horn <NUM>. This may be done by e.g. minimizing the number and size of any through-openings in housing <NUM>. Thus in some cases, earpiece body <NUM> does not have any (unoccluded) openings that lead into interior <NUM> of earpiece body <NUM> other than the first, sound-receiving opening <NUM> of acoustic horn <NUM>, and the sound-emitting outlet <NUM> of earpiece body <NUM>.

In further detail, at any location of housing <NUM> at which a through-opening might be necessary to accommodate a component such as e.g. a switch, such a component may be mated to its through-opening so that it at least substantially occludes the opening (e.g., to form a tight seal). To aid in this, any suitable gasket, sealant, adhesive, or the like, can be used in mounting any such component to a through-opening in housing <NUM>. (Similarly, if two or more housing pieces are mated together to form housing <NUM>, any suitable gasket, sealant, adhesive, or the like may used to similar effect. ) Beyond this, in at least some cases acoustic horn <NUM> may be configured so that it comprises no openings other than the aforementioned entrance <NUM> and exit <NUM>. So, any stray airborne noise that may penetrate into interior <NUM> of earpiece body <NUM>, may be at least substantially prevented from entering horn <NUM>. Likewise, any stray airborne noise that may penetrate around the outside of earpiece body <NUM> may be at least substantially prevented (by way of the above-described external occluding achieved by eartip <NUM>) from flowing around the outside of eartip <NUM> to reach the inner ear of the user. Still further, a tight seal between eartip <NUM> and e.g. protrusion <NUM> of earpiece body <NUM> may at least substantially prevent any stray airborne noise that may penetrate around the outside of earpiece body <NUM>, from penetrating into internal passage <NUM> of eartip <NUM>. Such arrangements, however achieved, can provide that e.g. at least substantially all the airborne sound that reaches the inner ear of a user, is sound that has entered acoustic horn <NUM> through entrance <NUM> thereof and has passed through acoustic horn <NUM>, with advantageous results as discussed herein.

If desired, any suitable protective element may be positioned outward of at least a portion of horn entrance <NUM> e.g. to minimize the entry of debris into horn <NUM>. Such a protective element may be e.g. a mesh, screen, perforated plate, etc., and may be made of any suitable material. It may be removable and cleanable and/or replaceable if desired. If the solid materials of the protective element are e.g. sized and arranged so that the element is at least substantially acoustically transparent, the element may be ignored e.g. for purposes of calculating the area of opening <NUM> (i.e., the overall or nominal area may be used). However, if the solid materials of the protective element do have a non-negligible effect on airborne sound transmission, the "effective" area of opening <NUM>, modified e.g. in view of the % open area of any protective element that blocks a portion of the opening, may be used in such calculations.

An exemplary eartip <NUM> is shown in <FIG> and in isolated view in <FIG>. Eartip <NUM> comprises a through-passage <NUM>, that extends through eartip <NUM> from outward end <NUM> to inward end <NUM> and allows the passage of airborne sound therethrough. In at least some embodiments, through-passage <NUM> is an internal through-passage, meaning that throughout all of its length, passage <NUM> is radially surrounded by material of eartip <NUM> (rather than being e.g. a groove or channel that is open to a radially outermost surface of eartip <NUM>). Through-passage <NUM> (which may be at least generally aligned with a long axis of eartip <NUM>, e.g. as depicted in <FIG>) comprises a primary sound-receiving opening (e.g., opening <NUM> as depicted in <FIG>) that, when eartip <NUM> is attached to earpiece body <NUM>, receives airborne sound from earpiece body <NUM>. Through-passage <NUM> further comprises a secondary, sound emitting opening <NUM> that faces toward the inner ear of the user, so that airborne sound can be transmitted through internal through-passage <NUM> and directed therefrom toward the inner ear of the user.

In at least some cases, the fitting of at least a portion of eartip <NUM> into at least a portion of the ear canal externally occludes the ear canal. By externally occludes is meant that at least some radially outward surfaces (e.g., surfaces <NUM>) of the eartip are in sufficient contact with portions of the walls of the ear canal to substantially prevent ambient airborne sound from traveling along the ear canal in a space otherwise existing between the eartip and the ear canal walls so as to reach the inner ear. This can provide that at least substantially all, or essentially all, of the airborne sound that reaches the inner ear, does so by way of internal through-passage <NUM> (and thus has passed through the acoustic horn of the earpiece body, as discussed above). Eartip <NUM> may be tightly fitted to earpiece body <NUM> (e.g., in an at least substantially leak-proof manner) to further provide that any airborne sound that reaches the inner ear has passed through the acoustic horn of the earpiece body, again as noted above.

In further detail, by eartip is meant a body of which at least major portions thereof are resiliently compressible and/or deformable at least in a radially inward direction, so that when the eartip is inserted into an ear canal, at least some portions of the eartip are resiliently biased radially outward so that at least some radially outward surfaces of the eartip are held against portions of the walls of the ear canal so as to substantially or completely eliminate any air gap therebetween. Eartip <NUM> comprises a long axis L that, when device <NUM> is fitted in the ear of a human user, will typically be at least generally aligned with a long axis of the portion of the ear canal into which the eartip is fitted. Eartip <NUM> comprises an outward end <NUM> and an inward end <NUM>, end <NUM> being the end that is attached (whether permanently or detachably) to earpiece body <NUM> and end <NUM> being the end that resides closest to the inner ear of the user. Eartip <NUM> may be comprised of any suitable material or materials, in any suitable geometric configuration. In some embodiments, eartip <NUM> may be comprised of a resiliently deformable and/or compressible organic polymeric material, e.g. a suitable molded plastic material. In configurations of a first general type, the desired resilient compressibility of the eartip may be provided by properties of the organic polymeric material alone rather than by e.g. any particular geometric design. For example, in some cases eartip <NUM> might consist of a generally cylindrical and/or tapered main body, comprised e.g. of a resiliently compressible foam. In configurations of a second general type, the desired resilient compressibility may be provided or enhanced by the geometric design of at least some components of the eartip. For example, as shown in exemplary manner in <FIG>, an eartip <NUM> may comprise a main body (e.g., trunk) <NUM> comprising one or more radially-outward-protruding flanges <NUM> made of a resiliently deformable material. Insertion of such an eartip into an ear canal may result in such flanges being deformed (e.g., swept back toward outward end <NUM> of the eartip), with the desired resilient biasing of surfaces of the flanges against the walls of the ear canal being thus achieved. In specific cases, one or more flanges <NUM> may be provided already in a swept-back (flared or bell-like) configuration even before being inserted into an ear canal (as shown in exemplary manner in <FIG>). In particular cases, such flanges may be at least generally semi-hemispherical in shape. It will be appreciated that in configurations of this second general type, it may not be necessary that all, or even any, of the material of which eartip <NUM> is made must be significantly compressible, as long as at least certain components (e.g., flanges) of the eartip are resiliently deformable and are provided in geometric shapes that allow such deformation to provide the desired resilient biasing of surfaces of such components against the ear canal walls.

In some cases (whether eartip <NUM> comprises flanges or not), eartip <NUM> (e.g. main body <NUM> and any flanges that may be present) may consist of a single (e.g., molded) piece of organic polymeric material, e.g. a resiliently deformable and/or compressible material. In other cases, eartip <NUM> might comprise e.g. a main body that is not necessarily resilient and/or compressible, but radially outwards of which main body is mounted one or more resiliently deformable flanges, one or more annular layers of a resiliently compressible material, or the like. (It will be appreciated that in designs of the general type shown in <FIG>, it may be desirable that at least the outward portion of main body <NUM> of eartip <NUM> may be resiliently deformable, in order to facilitate e.g. the stretch-fitting of an outward opening (e.g., <NUM>) of eartip <NUM> over protrusion <NUM> of earpiece body <NUM>).

In some cases, eartip <NUM> may exhibit a tapered shape with inward end <NUM> (that faces toward the inner ear) being the narrow end, whether eartip <NUM> is in the form of a single piece, or whether such a tapered shape is provided stepwise by a plurality of flanges of different diameters. Although three flanges (44a, 44b, and 44c) each with ear canal wall-contacting surfaces are shown in <FIG>, any number of flanges might be used. It will be appreciated that a wide variety of arrangements are possible and that the particular designs depicted in <FIG> are merely exemplary designs. In various configurations, a resiliently deformable and/or compressible portion of eartip <NUM> (or the entirety thereof), may be made of a material that exhibits a hardness of less than about <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> on a Shore A scale. In particular cases, such an eartip or a portion thereof may be made of a material that exhibits a hardness of from about <NUM> to about <NUM> on a Shore A scale. Whatever the specific design of eartip <NUM>, at least some portion of eartip <NUM> may conveniently be chosen to have a radial diameter that (when the components of eartip <NUM> are in an undeformed and/or uncompressed state) is at least somewhat larger than the average diameter of the outer ear canal of an adult human, in order to provide that insertion of eartip <NUM> into the ear canal will achieve the desired resilient biasing of surfaces of the eartip against the walls of the ear canal. While an exemplary style of eartip has been described in detail, it is emphasized that the herein-described earpiece body with a convoluted acoustic horn, can be used with any suitable eartip, of any suitable design and made of any suitable material.

The physiology and features of a human ear will be briefly summarized so that the fitting of the present device into the ear of a user can be described in precise detail. With reference to <FIG>, the external human ear <NUM> includes a broad structure <NUM> called the pinna. Pinna <NUM> includes a prominent exterior curved rim <NUM> called the helix, that originates in an upper base region <NUM> called the helix crus, and that extends therefrom in a counterclockwise direction along the radially outer edge of the pinna. Radially inward from the helix <NUM> is another curved prominence <NUM> called the antihelix, which extends from an upper base region <NUM> called the antihelix crura, in a generally counterclockwise direction so as to partially circumferentially surround a somewhat bowl-shaped depression <NUM> known as the concha. Concha <NUM> is at least partially divided by the helix crus <NUM> into a lower part <NUM> called the cavum concha, and an upper part <NUM> called the cimba concha. The inwardmost regions of concha <NUM> lead to the ear canal <NUM>, which is a somewhat circular or oval (in cross-section) passage that leads to the eardrum and the inner ear.

The antihelix <NUM> exhibits a radially inward-facing rim <NUM> which, along at least some or most of its length, may protrude slightly radially inward so as to provide a lip or flange that slightly overhangs the radially outward edge of concha <NUM>. The lowermost portion of the antihelix <NUM> (e.g., portion <NUM> as shown in <FIG>) becomes the antitragus <NUM>, which is a prominence that extends radially inward over the edge of the cavum concha (and which typically exhibits a more pronounced radially-inwardly-extending lip than does antihelix <NUM>). Across the lower portion of the cavum concha from the antitragus is another radially-inward-extending prominence <NUM> called the tragus, which (in similar manner to the antitragus), typically exhibits a more pronounced lip than does the antihelix, and which may often slightly outwardly cover a portion of the ear canal <NUM>.

Device <NUM> as disclosed herein is configured (sized and shaped) so that device <NUM> can be securely and comfortably retained in place in the ear of a user. While in some cases at least earpiece body <NUM> may be custom-made to fit a particular user's ear, in other cases the fit and retention of device <NUM> in a user's ear may be achieved without requiring device <NUM> to be custom-shaped to fit in the ear of that specific user. Thus in some examples device <NUM> (and earpiece body <NUM> and eartip <NUM> thereof) is not a custom-made device (e.g., a device of which any portion of any component is made according to a mold or <NUM>-D image of the ear of a particular user). Moreover, in at least some examples, earpiece body <NUM> is at least semi-rigid or rigid and is not significantly compressible, or deformable in any manner, by the user in ordinary operation of device <NUM>.

In at least some cases a device <NUM> may be configured so that it can fit in the right ear of a user and can also fit in the left ear of the user. In such cases it is not necessary to provide differently-configured (e.g., shaped) earpiece bodies <NUM> to be used in the right and left ears of a user; rather, a pair of identically shaped devices can be supplied. In other cases, earpiece bodies <NUM> may be supplied of somewhat different shape, for the right and left ear.

In some examples it may be useful to provide earpiece body with a relatively degree of bilateral symmetry in its overall shape. For example, earpiece body <NUM> may exhibit sufficient bilateral symmetry (i.e., when viewed along the inward-outward axis IOa of the earpiece body) to fit comfortably in a right ear or in a left ear, as desired. It is noted however that any desire for the overall shape of earpiece body <NUM> to have relatively high bilateral symmetry, does not require that the placement of various features (in particular, horn entrance <NUM> and protrusion <NUM>) must necessarily exhibit bilateral symmetry. Nor does it preclude the presence of small, local asymmetries in the shape of earpiece body <NUM>, as long as sufficient bilateral symmetry of the overall shape of earpiece body <NUM> is maintained.

The degree of overall bilateral symmetry of the shape of earpiece body <NUM> may be gauged by taking the projected area of earpiece body <NUM> on a plane that is substantially perpendicular to the inward-outward axis IOa of earpiece body <NUM>, and identifying an axis of symmetry that runs at least generally along a long axis of the projected area and that divides the projected area into two (e.g. roughly equal) partial-areas. One of the partial-areas can then be rotated around the axis of symmetry onto the other partial-area (i.e., as if folding the projected area along the axis of symmetry to bring one partial-area over onto the other partial-area). The percentage of their areas that the two partial-areas share in common can be measured and represents the degree of bilateral symmetry that exists. By an earpiece body having an at least generally bilaterally symmetrical shape is meant that two partial-areas generated and measured in this manner share at least <NUM> % of their area in common. (The bilateral symmetry of an exemplary earpiece body <NUM> may be most easily seen in the view of <FIG>. ) In various embodiments, earpiece body <NUM> may comprise a bilateral symmetry of at least about <NUM>, <NUM>, <NUM>, or <NUM> %.

In at least some cases, earpiece body <NUM> may exhibit an at least generally oval shape (when viewed along the long axis of eartip <NUM>). The terminology of generally oval includes ovals, ellipses, rectangles with one or more rounded corners, teardrop shapes, and so on. In the specific earpiece body illustrated in <FIG>, earpiece body <NUM> is of generally oval shape with end <NUM> (at which end eartip <NUM> is attached) being somewhat narrower than opposite end <NUM> (thus earpiece body <NUM> is somewhat teardrop-shaped, with a tapered end <NUM> and a blunt end <NUM>, in this example).

Shapes of these general types may allow one or more surfaces of earpiece body <NUM> to reside closely adjacent to (and in some instances to contact) a surface of an ear component that defines at least a portion of the radially outer perimeter of concha <NUM>. Such ear components may include e.g. any or all of the tragus <NUM>, the antitragus <NUM>, and portions of the radially inward-facing rim <NUM> of the antihelix <NUM>. Such arrangements can serve (e.g. in combination with the fitting of eartip <NUM> in ear canal <NUM>) to retain device <NUM> securely and yet comfortably in the concha <NUM> of a human ear. This is illustrated in exemplary manner in <FIG>, which shows an exemplary earpiece body <NUM> (with eartip <NUM> and ear canal <NUM> omitted from this view for ease of presentation) seated in the right ear of a human user.

The dimensions and shape of earpiece body <NUM> are thus configured so that earpiece body <NUM> can reside in the concha <NUM> (in specific cases, in the cavum concha <NUM>) of a human ear. For example, inward surface <NUM> of earpiece body <NUM> may be shaped so that when device <NUM> is fitted in the ear, some or most of the area of inward surface <NUM> may be in contact with (skin) surfaces that define the inward limits of concha <NUM>. (Although shown as relatively planar in the exemplary depictions of <FIG> and <FIG>, in some cases surface <NUM> may exhibit a curved (e.g., convex) shape. ) And, as mentioned above, one or more contact surfaces of earpiece body <NUM> (e.g., surface <NUM> as shown in <FIG>) can be provided (whether spaced apart, or extending continuously) around at least a portion of the perimeter of earpiece body <NUM>, which contact surface or surfaces are configured so that when device <NUM> is fitted in the ear of a user, at least one contact surface is in contact with a (skin) surface of an ear component that defines at least a portion of the radially outer perimeter of concha <NUM> (e.g., of cavum concha <NUM>).

In some cases, earpiece body <NUM> can be sized and shaped so that at least one generally outward-facing or radially-outward-facing contact surface (e.g. surface <NUM>) of earpiece body <NUM> is able to fit at least partially inwardly underneath (and in some instances, to contact) an inwardly-facing surface of a radially-inwardly-protruding edge (e.g., lip) of an ear component that defines a portion of the radially outer perimeter of the concha. Thus, in some examples, earpiece body <NUM> of earpiece body <NUM> may comprise various contact surfaces that are respectively configured to reside in radially-inward proximity, and/or in inward proximity, to a radially inward-facing surface (e.g., a radially-inward-protruding lip) of the tragus <NUM>, of the antitragus <NUM>, and/or of a portion <NUM> of the antihelix that is proximate the antitragus. (In this context, by a portion of the antihelix that is proximate the antitragus means a portion that is within about <NUM> of the radially-inwardmost-projecting part of the antitragus, measured in a clockwise direction around the antihelix. ) One such configuration is shown in exemplary illustration in <FIG>, in which a contact surface proximate of blunt end <NUM> of earpiece body <NUM> inwardly underlies, and may be in contact with, a portion of a lip of antitragus <NUM>. Similarly, a contact surface of tapered end <NUM> of earpiece body <NUM> inwardly underlies, and may be in contact with, a portion of a lip of tragus <NUM>. For many users, tapered end <NUM> of earpiece body <NUM> being "tucked under" the lip of tragus <NUM> in this manner, may be a primary mechanism in which the holding of earpiece body <NUM> in the concha is enabled or enhanced. However, it is emphasized that depending on the particular shape of the components of a particular user's ear, any individual contact surface (or portion thereof) or earpiece body <NUM>, may or may not necessarily contact the (skin) surface of any particular ear component (that defines at least a portion of the radially outer perimeter of the concha of that user's ear).

Thus in broad summary, in some cases earpiece body <NUM> may be configured so that device <NUM> may be held in position in a human ear by way of at least one contact surface of earpiece body <NUM> of device <NUM> being adjacent to (e.g., in contact with) a skin surface that defines at least a portion of the radially outer perimeter of concha <NUM>, in combination with the fitting of eartip <NUM> into ear canal <NUM>. (Such arrangements may be distinguished from arrangements in which a device is substantially, or essentially, supported and held in place in the ear only by the fitting of an eartip of the device into the ear canal. ) In further caeses, earpiece body <NUM> may be configured so that device <NUM> may be held in position in a human ear at least in part by way of two or more contact surfaces of earpiece body <NUM> (e.g., at different locations along the radially outer perimeter of earpiece body <NUM>) being adjacent to (e.g., in contact with) respective skin surfaces that define at least a portion of the radially outer perimeter of concha <NUM>. In various configurations, when device <NUM> is fitted into the ear of a user, two such areas of contact between contact surfaces of earpiece body <NUM> and surfaces of ear components defining portions of the radially outer perimeter of concha <NUM>, may be spaced around the perimeter of earpiece body <NUM> with a circumferential separation of at least <NUM>, <NUM>, or <NUM> degrees (in either a clockwise or a counterclockwise direction). Such an arrangement is shown in exemplary configuration <FIG>, with two such areas of contact (with a portion of the tragus, and with a portion of the antitragus, respectively) having a circumferential separation judged to be in the range of about <NUM> degrees.

While in some cases the fitting of eartip <NUM> into ear canal <NUM> may augment the above effects in securely fitting device <NUM> into a human ear, the providing of at least one contact surface (and particularly, two or more such surfaces) around the perimeter of earpiece body <NUM> may allow for less aggressive fitting of eartip <NUM> into the ear canal (that is, eartip <NUM> may not need to be fitted as deep into the ear canal), thus providing increased comfort for the user while allowing device <NUM> to still be securely held in place. That is, in such cases eartip <NUM> may only need to be fitted into the ear canal to an extent sufficient to provide the aforementioned external occlusion rather than to serve as the primary mechanism for securing device <NUM> in the ear. Thus in some cases, device <NUM> may be held in place in the ear partially, substantially or essentially completely by way of a compression fit of earpiece body <NUM> of device <NUM>, between portions of components defining the radially outer perimeter of the concha, e.g. between any combination of a tragus, an antitragus, and/or a portion of an antihelix that is proximate the antitragus, of a user's ear.

In some examples, the inward-outward dimension of earpiece body <NUM> (i.e., the average distance between inward surface <NUM> and outward surface <NUM> may be kept to a minimum so that no portion of earpiece body <NUM> extends outward beyond an imaginary plane that coincides with the outwardmost limit of the antihelix. This may provide that device <NUM> may be comfortable to wear even when a user is sleeping (e.g., so that device <NUM> does not protrude so far outward that positioning the user's head and ear in contact with a pillow might cause device <NUM> to exert an uncomfortable force on the user's ear). In at least some cases, when device <NUM> is fitted into a user's ear, all parts of earpiece body <NUM> may be generally, substantially, or completely, located within the cavum concha. In particular, in some cases earpiece body <NUM> will not comprise any protrusion that, when device <NUM> is fitted into a user's ear, extends upward into the cimba concha (e.g., in the manner of an arcuate protrusion that follows, and/or rests radially inward of, the rim of the cimba concha).

In some examples, an offset angle may be present between long axis L of eartip <NUM> and earpiece body <NUM> (specifically, between long axis L of eartip <NUM> and the inward-outward axis IOa of earpiece body <NUM>). Such an offset angle may provide enhanced comfort of device <NUM> when fitted into a user's ear. Thus, the exemplary design shown in <FIG> provides an offset angle in the range of approximately <NUM>-<NUM> degrees. In various cases, such an offset angle may be at least about <NUM>, <NUM>, or <NUM> degrees. In further cases, such an offset angle may be at most about <NUM>, <NUM>, or <NUM> degrees. In many embodiments, the orientation of long axis L of eartip <NUM> may be dictated by the orientation of a mounting structure (e.g., protrusion <NUM>) of earpiece body <NUM> to which eartip <NUM> is mounted. Thus, in many cases, such an offset angle may established e.g. by the angle at which protrusion <NUM> extends away from earpiece body <NUM> of earpiece body <NUM>, as is the case in the exemplary embodiment best seen in <FIG>.

The above discussions are to be interpreted in view of the fact there exists some variation in the shape of human ears. Thus, the descriptions provided herein of fitting device <NUM> into a human ear, e.g. a concha, will be understood as applying to adults with ear geometries and features that would be considered by an audiologist as being representative of the average adult population of humans. It is noted that device <NUM> (specifically, earpiece body <NUM> and/or eartip <NUM> thereof) may be provided in multiple sizes, with, for any device <NUM>, the above descriptions being valid for at least the particular human population for which that size device <NUM> is configured. In specific examples, the fitting of device <NUM> into a concha as described herein may be evaluated with respect to the fitting of device <NUM> into an artificial ear (i.e., a molded plastic artificial pinna) suitable for use in the test methods outlined in ANSI S <NUM> (Methods for the Measurement of Insertion Loss of Hearing Protection Devices in Continuous or Impulsive Noise Using Microphone-in-Real-Ear or Acoustic Test Fixture Procedures) as specified in <NUM>. A specific example of such artificial ears are those available under the trade designation KB0077 (left) and KB0078 (right) from G. Sound & Vibration A/S (Holte, Denmark) for use with the G. 45CB Acoustic Test Fixture. Thus, in specific examples, earpiece body <NUM> is configured to have at least one contact surface that is configured to contact a "skin" surface that defines at least a portion of the radially outer perimeter of a concha, of an artificial ear that meets the requirements for use with the ANSI S <NUM> test method.

Although earpiece body <NUM> and eartip <NUM> have been described above in a configuration in which they are combined to form a hearing protection device <NUM>, it is emphasized that in at least some cases earpiece body <NUM> may be supplied without an eartip attached thereto. That is, an earpiece body <NUM> may be supplied to a user who may then use it in combination with any suitable eartip. Moreover, in some cases at least one earpiece body and at least one eartip may be packaged together e.g. in the form of a kit. Such a kit may include instructions for use (noting that such instructions may be virtual instructions, e.g. in the form of a listed website that can be visited to read or upload a user guide or the like).

Although the discussions above have primarily concerned a passive hearing protection device, in other examples an earpiece body as disclosed herein may be used in an electronic hearing protection device. By this is meant a device that substantially prevents ambient airborne sound from directly entering the ear canal, and that includes electronic components that receive ambient airborne sound, convert the sound to electronic signals, process the electronic signals, convert the processed electronic signals into processed sound, and then emit the processed sound into the ear canal. It is emphasized however, that an earpiece body comprising a convoluted acoustic horn as disclosed herein, is configured for use in a hearing protection device (whether passive or electronic), which device is distinguished from both passive and electronic hearing-assistive devices (e.g., hearing aids, and ear trumpets).

It is noted that in discussions herein, various devices, components and arrangements have been characterized as e.g. "substantially preventing" the passing of airborne sound waves. It will be understood that such terminology does not require that such a device, component or arrangement necessarily provide an absolute barrier to airborne sound. Rather, the only requirement signified by this terminology is that all such components and arrangements collectively provide sufficient barrier properties to airborne sound that device <NUM>, comprising eartip <NUM> and earpiece body <NUM> as disclosed herein, is capable of functioning as disclosed herein.

A Working Example earpiece body was made by rapid prototyping methods (stereolithography), of a design generally similar to that shown in <FIG>. In this prototype, the earpiece body was an otherwise solid structure (made of plastic) comprising a convoluted, helical acoustic horn of similar layout to that seen most easily in <FIG>. The horn had an outward-facing, circular, unobstructed entrance of <NUM><NUM> in area, a generally inward-facing exit of approximately <NUM><NUM> in area, and a path length of approximately <NUM>. The earpiece body comprised a protrusion of similar design to that seen most easily in <FIG> and <FIG>, which protrusion included a chamber into which was placed a level-dependent acoustic filter of the type used in the hearing-protection product available from <NUM> Company under the trade designation COMBAT ARMS EARPLUGS. An eartip of generally similar type depicted in <FIG> was press-fitted onto the protrusion of the earpiece body to form a Working Example passive hearing protection device. The hearing protection device was positioned in the ear of a KEMAR G. 45CB manikin. The insertion loss (measured relative to the G. 45CB manikin in the absence of the prototype hearing protection device) was measured by conventional methods (using pink noise) and is presented in <FIG>.

For comparison, the insertion loss was similarly measured for a conventional passive hearing protection device (that did not include any kind of acoustic horn, but that did include the same acoustic filter that was used in the Working Example and that also used the same eartip that was used in the Working Example). It is evident that the Working Example exhibited significantly less Insertion Loss than the conventional hearing protection device, particularly in a frequency range above approximately <NUM>.

Claim 1:
An earpiece body that is configured to reside in the concha of a user's ear and that comprises a convoluted acoustic horn that is configured to receive airborne sound waves through a first, sound-receiving opening and to emit airborne sound waves through a second, sound-emitting opening, the first, sound-receiving opening and the second, sound-emitting opening being fluidly connected with each other so as to provide the convoluted acoustic horn;
wherein the earpiece body is configured to accept an eartip that is attachable thereto, the eartip being configured to fit into the ear canal of the user's ear and the earpiece body and the eartip combining to provide a passive hearing protection device;
wherein the first, sound-receiving opening is larger in cross-sectional area than the second, sound-emitting opening by an incremental percentage of from <NUM> to <NUM>; and wherein the second, sound-emitting opening is an offset opening that, when viewed along an inward-outward axis of the earpiece body, does not overlap the geometric center of the earpiece body.