HK1194585A - Earpiece passive noise attenuating - Google Patents

Description

Earphone passive noise attenuation

Background

This specification describes a structure for providing passive noise attenuation through an in-ear headphone and for positioning and retaining the headphone in the ear.

Disclosure of Invention

In one aspect, an in-ear headphone comprises: an acoustic driver; an acoustic channel that conducts sound waves emitted by the acoustic driver to the ear canal of the user; a positioning and retaining structure that engages a side feature of a user's ear to position and hold the headset in place without any structure external to the headset; and a generally conical structure configured such that a smaller end of the conical structure is smaller than an entrance of the user's ear canal and a larger end of the conical structure is larger than the entrance of the user's ear canal and is formed of a material that conforms to the entrance of the ear canal to seal the ear canal. The material may have a hardness of 30 shore a or less. The material may have a modulus of 2gf/mm or less. The material may be silicone rubber. The material may be a thermoplastic elastomer. The material may be a thermoplastic polyurethane. The positioning and retaining structure may comprise a first leg and a second leg attached to each other at an attachment end to form a plug and attached at the other end to the body of the headset. The positioning and retaining structure may provide at least three modes to prevent the headset from rotating clockwise beyond a rotated position. The pattern may include the tip of the plug contacting the bottom of the helix; the end of the plug is wedged under the antihelix in the cymba concha area; and the inner leg contacts the bottom of the helix. The positioning and retaining structure may include an inner leg and an outer leg. The inner leg and the outer leg may be attached to the main body at an attachment end and to each other at a link end. When the earpiece is in its intended position, the outer leg may push against the antihelix at the rear of the concha, the body engaging the ear canal; and at least one plug under the antihelix; or a portion of at least one of the body and the outer leg is below the antitragus. The positioning and retaining structure may comprise an inner leg and an outer leg attached to each other at an attachment end and to the earpiece body at a second end. The inner leg and the outer leg may be arranged to provide at least three modes for preventing clockwise rotation of the headset. The pattern may include the plug contacting a bottom of the helix; the plug is wedged below the antihelix; and the inner leg contacts the bottom of the helix. The inner and outer legs may be further arranged such that when the earphone is in its intended position, the outer leg is pushed against the antihelix at the rear of the concha, the body engaging the ear canal; and at least one plug under the antihelix; or a portion of at least one of the body and the outer leg is below the antitragus. The generally conical structure may include an opening therethrough to conduct sound waves from the acoustic driver to the ear canal. The cross-section of the opening may be substantially elliptical. The generally conical structure may taper substantially linearly from the large end to the small end. The generally conical structure may have a substantially uniform thickness. The material of the user's positioning and retaining structure may have a different hardness than the generally conical structure. The material of the structure that conducts the sound waves emitted by the acoustic driver to the ear canal of the user may have a different hardness than the material of the positioning and retaining structure of the user and the material of the generally conical structure.

In another aspect, an earplug for an in-the-ear earpiece includes a positioning and retaining structure to engage an ear-side feature to position and retain the earpiece in place without any structure external to the earpiece, and a generally conical structure configured such that a smaller end of the conical structure is smaller than an ear canal entrance of a user and such that a larger end of the conical structure is larger than the ear canal entrance of the user, and is formed of a material that conforms to the ear canal entrance to seal the ear canal. The positioning and retaining structure and the generally conical structure may comprise the same material. The positioning and retaining structure and the generally conical structure may be a unitary structure.

Drawings

Other features, objects, and advantages will become apparent from the following detailed description when read in conjunction with the following drawings, in which:

FIG. 1A is a side view of a human ear;

FIGS. 1B and 1C are exemplary cross-sections of a human ear;

fig. 2 is a perspective view of the headset;

FIG. 3 is a side view of an earphone and a human ear;

FIG. 4 shows cross-sections of two exemplary human ears;

FIGS. 5A-5D are views of a headset;

FIG. 6 shows cross-sections of two exemplary human ears;

FIGS. 7A-7C are views of a portion of the headset of FIGS. 2 and 5A-5D;

FIGS. 8A and 8B are cross-sections of the earphone portion of FIGS. 7A-7C; and

fig. 9A-9C are views of an alternative embodiment of a headset.

Detailed Description

This specification describes an in-ear headphone designed to fit in the right ear. The headset designed to fit in the left ear is a mirror image of the headset described below, operates according to the same principle and is therefore not described here.

FIG. 1A shows the side of a human right ear, with some features identified. There are many different ear sizes and geometries. Some ears have additional features not shown in fig. 1A. Some ears lack some of the features shown in fig. 1A. Some features may be more or less prominent than that shown in fig. 1A. Fig. 1B and 1C show two exemplary cross-sections of a human ear, with some features identified. The ear canal is an irregularly shaped cylinder with a variable cross-sectional area and a straight centerline. Some of the features identified are the entrance of the ear canal and a major portion of the ear canal. In this specification, the entrance of the ear canal refers to the portion of the ear canal near the concha (concha), where the wall of the ear canal is not substantially parallel to the centerline of the ear canal. The exact structure of the human ear varies widely from individual to individual. For example, in the cross-section of FIG. 1B, there is a relatively sharp transition from the wall of the ear canal that is not parallel to the centerline 30-1B of the ear canal to a wall that is substantially parallel to the centerline of the ear canal, such that the entrance 32-1B of the ear canal is relatively short. In the cross-section of fig. 1C, there is a more gradual transition from a wall that is not parallel to the centerline of the ear canal to a wall that is substantially parallel to the centerline 30-1C of the ear canal, so that the entrance 32-1C of the ear canal is relatively long.

Fig. 2 shows a headset 10. The earphone 10 may include a tang 52 for locating a cord or the like, the acoustic driver module 14, and a plug 60 (more clearly identified in fig. 5A-5D). Some headphones may lack tang 52 but may include an electronics module (not shown) for wireless communication with an external device. Other headphones may lack a tang and acoustic driver module and may be used as passive earplugs. Plug 60 includes a locating and retaining structure 20, which in this example includes an outer leg 22 and an inner leg 24. The plug also includes a sealing structure 48.

In operation, the headset 10 may be placed in the ear and oriented and held in place by the positioning and retaining structure 20 and other portions of the headset. The plug 60 includes a channel that conducts sound waves emitted by the acoustic driver in the acoustic driver module 14 to the ear canal. The positioning and retaining structure 20 holding the earpiece in place extends from the plug 60, the portion of the earplug that engages the ear canal does not contribute significantly and there is no structure on the outside of the earplug. The positioning and retaining structure 20 includes at least an outer leg 22 and an inner leg 24 joined at one end to the rest of the earplug and at the other end to each other. The outer leg is curved so as to generally follow the curve of the antihelix and/or cymba concha at the rear of the concha. Generally, the compliance/stiffness of the entire positioning and retaining structure is important over the compliance/stiffness of the material from which the positioning and retaining structure is made or any one component of the positioning and retaining structure. The outer leg 22 and the inner leg 24 may lie in a plane.

Referring now to fig. 3, the earpiece plug is placed in the ear and pushed gently inward, preferably rotating counterclockwise as indicated by arrow 43. Pushing the body into the ear causes the outer leg 22 to seat in place under the anthelix and, depending on the size and geometry of the entrance to the ear canal, causes the outlet section of the plug 48 (not shown in this view for convenience) to enter the ear canal by a small amount.

The body is then rotated clockwise as indicated by arrow 41 until a condition occurs in which the body cannot be rotated any further. This condition may include: the tip 35 of the plug may contact the bottom of the helix; the inner leg 24 may contact the bottom of the helix; or the tip 35 may become wedged behind the antihelix in the cymba concha area. While the positioning and retaining structure provides all three conditions (hereinafter "modes"), not all users will have three conditions, and for the majority of users will have at least one mode. Which conditions occur will depend on the size and geometry of the user's ear.

Rotating the headset clockwise also causes the tip and outer leg to engage the cymba concha area and sit under the antihelix. When the body is in place with the positioning and retaining structure 20, the positioning and retaining structure and/or the body contact the ears of most people in at least two ways, and for many people contact their ears in more several ways: the length 40 of the outer leg 22 contacts the antihelix at the rear of the concha; the end 35 of the positioning and retaining structure 20 is below the antihelix; either the outer leg 22 or a portion of the plug 60 (of the previous figures) or both are below the antitragus; and the plug 60 contacts the entrance to the ear canal below the tragus. Two or more point contacts hold the headset in place, providing greater stability. The distribution of forces and the flexibility of the various parts of the body and the outer legs contacting the ear reduce the pressure on the ear, providing a more comfortable fit.

It is desirable to place the headset in the ear with its proper orientation, so as to be stable (i.e., resting in the ear), comfortable, and for some applications provide significant passive attenuation of ambient noise. One method of providing stability and proper orientation is described above and more fully in U.S. patent application 12/860531, which is incorporated herein by reference in its entirety.

One device for providing significant passive attenuation is a structure that fits in the main part of the ear canal and itself seals to the ear canal by exerting radial pressure on the wall of the main part of the ear canal as indicated by arrows 70, 72 and 74 in fig. 4 (e.g., a "christmas tree" structure as described in us patent application 2004/0163653, or a "mushroom" structure as described in us patent 5957136, or a disc-shaped flange or similar structure as described in us patent 6129175). The radial pressure may originate from or be supplemented by an inward clamping pressure. Such devices may have some undesirable side effects, such as poor sealing, discomfort, or even pain, because the geometry and size of the ear canal varies widely with individuals, and because such devices in some individuals invade the ear canal farther than desired. The major part of the ear canal, especially close to the middle ear, is very sensitive, so that the further the structure extends into the ear, the less comfortable it is. Another device that provides significant passive attenuation is a structure that (in addition to the earpiece itself) provides inward clamping pressure that pushes the appropriate structure against the cephalad or otolateral sides. Examples include the headband of a conventional headset or the yoke of a stethoscope, such as described in us patent 4055233. However, for in-ear headphones, light weight and small size are desirable features, while the headband and yoke add weight and structure.

The earpiece of fig. 2 includes a plug that provides orientation, stability and a good seal for the entrance of the ear canal and the ear structure outside the ear canal, without excessive radial pressure, and without inward clamping pressure provided by sources not included in the earpiece.

Fig. 5A-5D show several views of the plug 60. Not all elements of the plug 60 are identified in all views. Plug 60 includes positioning and retaining structure 20, body 23, passageway 21, and seal structure 48. The body includes a mating surface 25 for connection to the driver module 14. The passageway 21 conducts sound from the driver module, through the body and the sealing structure and into the ear canal. Seal 48 comprises a frusto-conical configuration. The frusto-conical structure may have an elliptical or oval cross-section (as viewed in fig. 7A below), with the walls tapering substantially linearly (as viewed in fig. 7B, 8A and 8B below). In one implementation, the structure of the seal structure and the materials from which it is made result in a modulus in the range of 0.2 to 2gf/mm measured in the direction of arrow 34 of FIG. 5B. Examples of suitable materials include silicone, TPU (thermoplastic polyurethane), and TPE (thermoplastic elastomer).

The plug's smaller end 62 is sized so that it fits a small amount inside the ear canal of most users so that the sealing structure 48 contacts the entrance of the ear canal but not the inside of the ear canal. The larger end 64 of the plug is sized so that it is larger than the entrance to the ear canal of most users.

Positioning and retaining structure 20 and seal structure 48 may be a single piece, made of the same material, for example, very soft silicone rubber, having a hardness of 30 shore a or less. The wall of the sealing structure 48 may have a uniform thickness, which may be very thin, e.g., the thickest part of the wall is less than 1mm and may taper to the bottom of the frustoconical structure, such that the wall is easily deflected, thereby easily conforming to the contours of the ear and providing a good seal and good passive attenuation without exerting significant radial pressure on the ear canal. Since different parts of the headset function differently, it is desirable that the different parts of the headset are made of different materials, or of materials having different hardnesses or moduli. For example, the hardness (durometer) of the retention structure 20 may be selected for comfort (e.g., 12 Shore A), the hardness of the plug 48 may be slightly higher (e.g., 20 Shore A) for better fit and sealing, the hardness of the portion of the earplug mechanically coupling the earplug to the acoustic module 14 may be higher (e.g., 70 Shore A) for better retention and sealing to the portion of the earplug mechanically coupling the earplug to the acoustic module 14, and in some cases, for a more consistent shape and size of the channel through which the sound waves propagate.

The earplug according to fig. 5A-5D is sealed to the entrance of the ear canal to provide passive attenuation and to exert little radial pressure on the main part of the ear canal, or not at all, as shown in fig. 6.

Fig. 7A-7C show external views of the plug 60, and fig. 8A and 8B show cross-sectional views of the plug 60, with the plug having dimensions of an exemplary embodiment. In the implementation of fig. 7A-7C and 8A and 8B, seal 48 is oval with a major axis of 7.69mm at the smaller end and a minor axis of 5.83mm, and a major axis of 16.1mm and a minor axis of 14.2mm at the larger end. Sealing structures having these dimensions fit into the ear canal of many users such that the smaller end extends a small amount into the ear canal and does not contact the walls of the ear canal, such that the larger end does not fit in the ear canal, and such that sealing structure 48 engages the entrance of the ear canal. Smaller or larger versions may be used for users with ears below or above average size, including children. Versions with similar overall dimensions but different aspect ratios between major and minor axes may provide users with ear canal entrances that are more or less circular than average.

In some instances, sealing structure 48 and body 23 together are sufficient to position and retain the earphone in the ear of the user, and need not include retaining structure 20. Such a design 60' is shown in fig. 9A to 9C. Friction and interference between the body 23 and the earshell holds the headset. Positioning is aided by the geometric relationship between the body 23 and the sealing structure 48 such that the body fits within the concha when the sealing structure is properly positioned and sealed to the entrance of the ear canal. Adding at least one of the body 23 or the retaining structure 20 (e.g., from fig. 2) to the sealing structure 48 eliminates the need for the sealing structure to retain the earpiece itself, which allows the sealing structure to be more compliant and deformable as may be required if it is also responsible for retaining the earpiece.

The generally frustoconical shape of the seal structure, i.e., its substantially linear sides in combination with its thin walls and elliptical cross-section, allows the seal structure to be more deformable than prior art seal structures that tend to have rounded walls (i.e., mushroom-shaped rather than tapered). The circular wall has greater enveloping strength such that if it is compressed along one lateral axis (i.e., an axis perpendicular to an axis through the length of the structure), the structure bulges outward along the perpendicular lateral axis. In response to deformation in a first transverse axis, the wall becomes less compliant along the other transverse axis, such that compression from multiple radial directions can cause buckling along the curve of the wall, resulting in gaps in the seal between the seal structure and the ear, or pressure points where the sidewall cannot compress in all directions. In contrast, the thin tapered wall of seal 60 may compress in multiple directions simultaneously without buckling or increasing pressure elsewhere.

Various uses of, and departures from, the specific apparatus and techniques disclosed herein may be made without departing from the inventive concepts. The invention, therefore, is to be construed as embracing each and every novel feature and novel combination of features disclosed herein and limited only by the spirit and scope of the appended claims.

Claims (24)

1. An earplug for an in-ear headphone, comprising:

a positioning and retaining structure that engages features of the sides of the user's ear to position and retain the headset in place without any structure external to the headset;

a generally conical structure capable of having a smaller end of the conical structure smaller than an entrance of a typical human ear canal and having a larger end of the conical structure larger than the entrance of the typical human ear canal, and the conical structure being formed of a material that conforms to the entrance of the ear canal to seal the ear canal.

2. The earplug of claim 1, further comprising a round body coupled to the cone-shaped structure, positioned near a larger end of the cone-shaped structure and adapted to rest in an earshell of an ear of a user.

3. The earbud of claim 2, wherein the round body comprises an earpiece mating surface for coupling to a housing of an electroacoustic transducer of an earpiece, such that the cone-shaped structure and the earbud body are positioned between the ear of the user and the housing when the earbud is inserted into the ear of the user.

4. The earplug of claim 2, wherein the earplug body is joined to the cone structure by a passageway that passes through an interior of the cone structure, terminating at a smaller end of the cone structure, the volume of air between the passageway and the walls of the cone structure providing space for the cone structure to deform upon insertion of the cone structure into the user's ear.

5. The earplug of claim 2, wherein the positioning and retaining structure comprises the round body.

6. The earplug of claim 1, wherein the positioning and retaining structure and the generally conical structure comprise the same material.

7. The earplug of claim 6, wherein the positioning and retaining structure and the generally conical structure are a unitary structure.

8. The earplug of claim 1, wherein the positioning and retaining structure comprises:

attached to each other at an attachment end to form a plug and attached at the other end to the outer and inner legs of the body of the headset.

9. The earplug of claim 1, wherein the generally conical structure tapers substantially linearly from the large end to the small end.

10. The earplug of claim 1, wherein the generally conical structure has a substantially uniform thickness.

11. The earplug of claim 1, wherein the cross-section of the generally conical structure is substantially elliptical.

12. The earplug of claim 1, wherein the material of the positioning and retaining structure has a different hardness than the generally conical structure.

13. The earplug of claim 1, wherein the generally conical structure has compliance and deformability allowing the wall to compress along two different transverse axes without buckling.

14. The earplug of claim 1, wherein the material has a hardness of 30 shore a or less.

15. The earplug of claim 1, wherein the material has a stiffness of 2gf/mm or less.

16. The earplug of claim 1, wherein the material is silicone rubber.

17. The earplug of claim 1, wherein the material is a thermoplastic elastomer.

18. The earplug of claim 1, wherein the material is a thermoplastic polyurethane.

19. The earplug of claim 1, wherein the generally conical structure includes an opening therethrough to conduct sound waves from an acoustic driver of the earpiece to the ear canal.

20. The earplug of claim 19, wherein a material of a structure surrounding the opening to conduct sound waves emitted by the acoustic driver to the ear canal of the user has a hardness different from a hardness of a material of the positioning and retaining structure and a material of the generally conical structure.

21. The earplug of claim 19, wherein the opening is substantially elliptical in cross-section.

22. The set of earplugs of claim 21, wherein the openings of at least two earplugs of the set have different elliptical eccentricities.

23. The set of earplugs of claim 22, wherein the positioning and retaining structures of at least two earplugs having openings with different eccentricities are the same size.

24. An in-ear headphone comprising the earplug of any of claims 1-21, further comprising an acoustic driver coupled to the earplug.