Ear tips and related devices and methods

Abstract

The eartip includes a body configured to be attached to an earbud. The body includes a first end, a second end opposite the first end, and an inner wall extending between the first end and the second end. The inner wall defines and encloses a hollow passage configured to conduct sound waves. The body also includes an outer wall connected to the inner wall at the first end and extending away from the inner wall toward the second end. The inner wall has an elongated cross-sectional shape configured to accommodate a corresponding nozzle on the earbud. The inner wall is formed from a rigid material and includes a ring that engages and conforms to the elongated shape of the nozzle, which prevents improper attachment and rotation of the eartip relative to the nozzle.

Description

Background Art

[0001] The present disclosure relates to ear tips and related devices and methods.

[0002] Modern in-ear headphones provide active noise reduction that helps reduce ambient noise in the user's external ear canal. Active noise reduction is generally achieved through the use of analog circuitry or digital signal processing. Adaptive algorithms are designed to analyze the waveform of the ambient noise and then generate a signal that phase-shifts or inverts the polarity of the original signal based on a particular algorithm. This inverted signal (opposite phase) is then amplified, and a transducer (speaker) generates sound waves that are proportional to the amplitude of the original waveform, creating interfering cancellation. This effectively reduces the volume of the perceivable noise.

[0003] An important complement to this active noise reduction is the passive attenuation of noise provided by the material that seals the user's external ear canal. In that regard, many modern in-ear headphones typically include compliant ear tips made from low durometer silicone. These ear tips form an acoustic seal with the user's external ear canal and act as a physical barrier to the transmission of ambient noise. The low durometer silicone provides comfort because it is flexible and compliant, helping to ensure a good acoustic seal with the user's external ear canal.

[0004] Active noise reduction is very effective at lower frequencies (e.g., 20 Hz to 1 kHz), but headphones rely heavily on passive attenuation to attenuate (reduce) higher frequency noise (e.g., above 1 kHz). Unfortunately, the low durometer silicone commonly used for ear tips is not particularly good at attenuating high frequencies in the range of 1 kHz to 1.5 kHz. This allows unwanted noise to pass through the ear tip material and into the user's external ear canal.

[0005] The present disclosure relates to an ear tip for headphones having improved passive attenuation. The present disclosure further relates to an ear tip designed to fit an oval nozzle and configured to resist rotation around the nozzle when fitted to the nozzle.

Summary of the Invention

[0006] All examples and features mentioned below can be combined in any technically possible way.

[0007] In one aspect, the ear tip includes a body configured to be attached to an earbud. The body includes a first end, a second end opposite the first end, and an inner wall extending between the first end and the second end. The inner wall defines and surrounds a hollow passage configured to conduct sound waves. The body also includes an outer wall connected to the inner wall at the first end and extending away from the inner wall towards the second end. The inner wall has an elongated cross-sectional shape configured to receive a corresponding nozzle on the earbud. The inner wall is formed of a rigid material, engages and conforms to the elongated shape of the nozzle, prevents improper attachment of the ear tip to the nozzle, and includes a ring that prevents rotation of the ear tip relative to the nozzle when the ear tip is attached to the nozzle.

[0008] Implementations may include one of the following features, or any combination thereof.

[0009] In some implementations, the inner wall further includes a high durometer compliant material that defines at least a portion of an extension extending between the nozzle and the first end of the ear tip.

[0010] In some implementations, the outer wall is molded around a high durometer compliant material and the outer wall is formed from a lower durometer compliant material.

[0011] In some cases, the ring includes at least one C-shaped member having at least one gap, and the high-durometer compliant material is molded around the ring to fill the gap.

[0012] In some cases, the ring includes a pair of C-shaped members arranged with a pair of gaps between the members, and the high-durometer compliant material fills both gaps.

[0013] In some cases, the high-durometer compliant material defines a retaining member configured to engage a mating retaining member on the nozzle.

[0014] In certain examples, the ring defines a recess extending around the inner surface of the inner wall and is configured to receive an O-ring seated within a corresponding recess formed on and extending around the outer surface of the nozzle.

[0015] In some implementations, the inner wall also includes an extension extending between the nozzle and the first end of the ear tip, and the outer wall and the extension are at least partially formed from a viscoelastic material having frequency-reinforcing behavior.

[0016] In a particular implementation, the extension and the outer wall are formed from a styrenic TPE having viscoelastic properties (e.g., A9 TPE).

[0017] In some cases, the outer surface of the outer wall is treated with a surface treatment selected from electron beam treatment and photoionization to improve sebum resistance.

[0018] In some cases, the outer surface of the outer wall has a soft-touch coating.

[0019] In some examples, the soft-touch coating is a 50% poly(styrene-isobutylene-styrene) (SIBS) block copolymer / 50% silicone (wt / wt) soft-touch coating.

[0020] In certain examples, the viscoelastic material is a composition comprising an elastomer and one or more phase change materials having the ability to undergo a phase change from a solid state to a liquid state at a predetermined phase change temperature.

[0021] In some implementations, the predetermined phase change temperature is from about 25 °C to about 35 °C.

[0022] In certain implementations, the composition has a hardness of from about 5 Shore A to about 50 Shore A, and the amount of the phase change material in the composition is from about 10 wt% to about 40 wt%.

[0023] In another aspect, the ear tip includes a body configured to be attached to an earbud. The body includes a first end, a second end opposite the first end, and an inner wall extending between the first end and the second end. The inner wall defines and surrounds a hollow passage configured to conduct sound waves. The body also includes an outer wall connected to the inner wall at the first end and extending away from the inner wall toward the second end. The inner wall is configured to engage a nozzle on the earbud. The inner wall includes an extension extending between the nozzle and the first end of the ear tip, and the outer wall and the extension are at least partially formed from a viscoelastic material including a styrenic TPE having viscoelastic properties (e.g., A9 TPE).

[0024] Implementations may include one or any combination of the above and / or the following features.

[0025] In some implementations, the outer surface of the outer wall is treated with a surface treatment selected from electron beam treatment and photoionization to improve sebum resistance.

[0026] In certain implementations, the outer surface of the outer wall has a soft-touch coating.

[0027] Optionally, the soft-touch coating is a 50% SIBS / 50% silicone (wt / wt) soft-touch coating.

[0028] In certain cases, the viscoelastic material includes a composition comprising a styrenic TPE having viscoelastic properties and one or more phase change materials having the ability to change phase from a solid state to a liquid state at a predetermined phase change temperature.

[0029] In some examples, the predetermined phase change temperature is from about 25 °C to about 35 °C.

[0030] In a particular example, the composition has a hardness of from about 5 Shore A to about 50 Shore A, and the amount of the phase change material in the composition is from about 10 wt% to about 40 wt%.

[0031] In some implementations, the viscoelastic material defines a retaining member configured to engage a mating retaining member on the nozzle.

[0032] In a particular implementation, the inner wall is also formed of a rigid plastic and includes a ring configured to engage the nozzle.

[0033] In some cases, the ring defines a recess extending around the inner surface of the inner wall and is configured to receive an O-ring formed on and extending around the outer surface of the nozzle and seated within a corresponding recess.

[0034] In a particular case, the styrenic TPE having viscoelastic properties is A9 TPE.

[0035] Another aspect features an ear tip configured to be worn on an earbud. The body includes a first end, a second end opposite the first end, and an inner wall formed of a first material having a first durometer. The inner wall extends between the first end and the second end. The inner wall defines and surrounds a hollow passage configured to conduct sound waves. The body also includes an outer wall formed of a second material having a second durometer smaller than the first durometer. The outer wall is connected to the inner wall at the first end and extends away from the inner wall toward the second end. The inner wall has an elongated cross-sectional shape configured to receive a corresponding nozzle on the earbud. The inner wall defines a retaining mechanism having two ends and two sides connecting them. The thickness of the sides is different from the thickness of the ends. The retaining mechanism engages and conforms to a complementary retaining mechanism of the nozzle, preventing improper attachment of the ear tip to the nozzle and preventing rotation of the ear tip relative to the nozzle when the ear tip is attached to the nozzle.

Brief Description of the Drawings

[0036]

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[0037] Components that are commonly labeled in the figures are considered to be substantially equivalent components for illustrative purposes, and duplicate descriptions of these components are omitted for clarity. The numerical ranges and values described according to various implementations are merely examples of such ranges and values and are not intended to limit these implementations. In some cases, the term "about" is used to modify a value, and in these cases, these values can refer to a margin of error such as a measurement error that can range up to 1 - 5 percent.

Mode for Carrying Out the Invention

[0038] Figures 1A, 1B, and 2 show an exemplary earpiece 100 configured in accordance with the present disclosure. The earpiece 100 includes an earbud 102 and an ear tip 104. The earbud 102 also includes a housing 106 that defines a nozzle 108 configured to be coupled to the ear tip 104. The housing 106 may be formed, for example, by molding, from a rigid plastic such as acrylonitrile butadiene styrene (ABS), polycarbonate / acrylonitrile butadiene styrene (PCB / ABS), polyetherimide (PEI), or stereolithography (SLA) resin. The housing 106 defines a cavity 110 in which an electroacoustic transducer 111 (also referred to as a "speaker" or "receiver" or "driver"), a battery 114, and an electronic circuit 116 may be disposed. The cavity 110 is acoustically coupled to an acoustic passage 112 within the nozzle 108 such that, for example, when the earpiece is attached, the electroacoustic transducer 111 may be acoustically coupled to the user's ear. The housing 106 may also support one or more microphones 118.

[0039] As shown in FIG. 1B, the nozzle 108 has an elongated cross-sectional shape, for example, an oval, an ellipse, a shape of a racetrack (having parallel sides and rounded ends extending between the parallel sides, also known as a "stadium"), or an elongated shape having rounded ends as shown in FIG. 1B and curved splines connecting them. Here, "cross-section" or "cross-sectional" is to be understood as being perpendicular to the central axis of the nozzle. This is expected to better conform to the user's ear canal than a simple circular cross-section. The earpiece 100 may also include stabilizing means to assist in holding the earpiece 100 within the user's ear.

[0040] Referring to FIGS. 3A-3D, the ear tip 104 is configured to at least partially fit within a person's ear canal. The ear tip 104 includes a body 120 configured to be mounted on the earbud 102. The body 120 includes a first end 122 and a second end 124 opposite the first end 122. The body 120 further includes an inner wall 126 extending between the first end 122 and the second end 124. The inner wall 126 defines and surrounds a hollow passage 128 configured to conduct sound waves. The inner wall 126 has an elongated cross-sectional shape, such as an ellipse, an oval, a racetrack shape (having parallel sides and rounded ends extending between the parallel sides, also known as a "stadium"), or an elongated shape having rounded ends as shown in FIG. 3B and curved splines connecting them. Here, "cross-section" or "cross-sectional" is to be understood as being perpendicular to the central axis of the inner wall 126. The body 120 also includes an outer wall 130 connected to the inner wall 126 at the first end 122. The outer wall 130 extends away from the inner wall 126 and toward the second end 124. In the illustrated example, the outer wall 130 is dome-shaped, however, other shapes such as conical are also contemplated. As shown in FIG. 3C, the outer wall 130 extends beyond the second end 124. In an alternative implementation, the outer wall 130 may extend toward the second end 124 but not necessarily reach the second end 124.

[0041] The embodiments shown in FIGS. 3A-3C form the ear tip 104 using three different materials of different hardnesses in a three-shot molding process. The first material, a rigid plastic (e.g., glass-filled polyimide), is used to provide a ring 132 that engages the nozzle 108 for anti-rotation. In this regard, the ring 132 conforms to the elongated shape of the nozzle 108, thereby preventing improper attachment of the ear tip 104 and preventing rotation of the ear tip 104 relative to the nozzle 108 when the ear tip 104 is attached to the nozzle 108. As shown in FIG. 4, the ring 132 can be C-shaped with a gap 134 that allows some compliance to enable the ring 132 to accommodate the nozzle 108.

[0042] The second material is a high durometer compliant material, such as high durometer silicone, for example 60 Shore A to 80 Shore A silicone, for example 70 Shore A silicone, which is formed around the ring 132. The ring 132 and the second material together form the inner wall 126. The second material extends around the inner surface of the inner wall 126 and defines a retaining mechanism 134, for example a protrusion, configured to engage a complementary retaining mechanism 136, for example a recess, defined by and extending around the outer surface of the nozzle 108. The engagement of the retaining mechanisms 134, 136 serves to hold the ear tip 104 on the nozzle 108 and provides a good acoustic seal between the earbud 102 and the ear tip 104.

[0043] The second material also fills the gap 134 within the ring 132, thereby allowing some compliance to fit onto the nozzle 108 and allowing the ends of the ring 132 to be displaced relative to each other while providing a closed shape (closed ring) to the second end 124 of the ear tip 104.

[0044] The second material further defines at least a portion of an extension 138 that extends between the nozzle 108 and the first end 122 of the ear tip 104. The use of a high durometer material in this region provides improved passive attenuation performance compared to prior art ear tips that used low durometer silicone in this region, although the low durometer silicone passes excessive noise.

[0045] Finally, the outer wall 130 is formed around a high durometer material. The outer wall 130 is formed of a low durometer material, such as a low durometer silicone, such as a 10 Shore A to 30 Shore A silicone, such as a 20 Shore A silicone, for comfort. The outer wall 130 is the portion of the ear tip that contacts and conforms to the user's ear canal and forms an acoustic seal therebetween. As shown in FIG. 3A, the outer wall 130 has an elongated cross-sectional shape, such as an ellipse, an oval, a racetrack shape (having parallel sides and rounded ends extending between the parallel sides, also known as a "stadium"), or a dome shape having an elongated shape with rounded ends and curved splines connecting them as shown in FIG. 3A. Here, "cross-section" or "cross-sectional" should be understood to be perpendicular to the central axis of the dome / outer wall 130.

[0046] The ear tip 104 can be formed in a three-shot molding process in which the ring 132 is formed in a first molding step, followed by the remainder of the inner wall 126 being formed in a second molding step, and finally the outer wall 130 being formed in a third molding step.

[0047] FIG. 5 shows an alternative implementation in which the ring 132 is formed from two separate C-shaped members, both formed from a rigid plastic material (such as glass-filled polyimide), and having a pair of gaps 500 between those portions. The gaps 500 are filled with a second material during the molding process.

[0048] Figures 6A - 6D illustrate another implementation of the ear tip 604 that includes a body 620 configured to be attached to an earbud (e.g., earbud 102 of FIGS. 1A and 1B). The body 620 includes a first end 622 and a second end 624 opposite the first end 622. The body 620 further includes an inner wall 626 that extends between the first end 622 and the second end 624. The inner wall 626 defines and surrounds a hollow passage 628 configured to conduct sound waves. The inner wall 626 has an elongated cross - sectional shape, such as an ellipse, an oval, a racetrack shape (having parallel sides and rounded ends extending between the parallel sides, also known as a "stadium"), or an elongated shape having rounded ends as shown in FIG. 6B and curved splines connecting them. Here, "cross - section" or "cross - sectional" is to be understood as perpendicular to the central axis of the inner wall 626. The body 620 also includes an outer wall 630 connected to the inner wall 626 at the first end 622. The outer wall 630 extends away from the inner wall 626 and towards the second end 624. In the illustrated example, the outer wall 630 has a dome - like shape, however, other shapes such as conical are also contemplated. As shown in FIG. 6C, the outer wall 630 extends beyond the second end 624. In an alternative implementation, the outer wall 630 may extend towards the second end 624 but not necessarily reach the second end 624.

[0049] The embodiments shown in FIGS. 6A - 6D form the ear tip 604 using three different materials of different hardnesses in a three - shot molding process. A first material, a rigid plastic (e.g., glass - filled polyimide), is used to provide a ring 632 that engages the nozzle 108 for anti - rotation. In this regard, the ring 632 conforms to the elongated shape of the nozzle 108, thereby preventing improper attachment of the ear tip 604 when the ear tip 604 is attached to the nozzle 108.

[0050] As shown in FIGS. 6C and 6D, the ring 632 defines a recess 634 (e.g., an annular groove) that extends around the inner surface of the inner wall 626 and is configured to receive an O-ring 635 (e.g., a rubber O-ring) that seats within a corresponding recess 136 (e.g., an annular groove) formed on and extending around the outer surface of the nozzle 108. In this implementation, the engagement of the retaining mechanisms 634, 136 and the O-ring 635 serves to hold the ear tip 604 on the nozzle 108 and also provides a good acoustic seal between the earbud 102 and the ear tip 604.

[0051] As shown in FIGS. 6C and 6D, the ring 632 can also define a lip 637 that overlaps the end of the nozzle 108. The lip 637 can support a wax guard 638, e.g., a screen that can be heat-sealed to the lip 637. This can be an alternative to, or in addition to, the wax guard 640 (FIG. 6D) on the nozzle 108 itself.

[0052] The second material is a high-durometer compliant material, such as high-durometer silicone, e.g., 60 Shore A to 80 Shore A silicone, e.g., 70 Shore A silicone, that is molded around the ring 632. The ring 632 and the second material together form the inner wall 626. The second material defines at least a portion of an extension 642 that extends between the nozzle 108 and the first end 622 of the ear tip 604. The use of the high-durometer material in this region provides improved passive attenuation performance compared to prior art ear tips that used low-durometer silicone in this region, where the low-durometer silicone would pass excessive noise.

[0053] Finally, the outer wall 630 is formed around a high durometer material. The outer wall 630 is formed from a low durometer compliant material, such as low durometer silicone, e.g., 10 Shore A to 30 Shore A silicone, e.g., 20 Shore A silicone, for comfort. The outer wall 630 is the portion of the ear tip that contacts and conforms to the user's ear canal and forms an acoustic seal therebetween. As shown in FIG. 6A, the outer wall 130 has an elongated cross-sectional shape, such as an ellipse, an oval, a racetrack shape (having parallel sides and rounded ends extending between the parallel sides, aka "stadium"), or a dome shape having an elongated shape with rounded ends and curved splines connecting them as shown in FIG. 6A. Here, "cross-section" or "cross-sectional" is to be understood as being perpendicular to the central axis of the dome / outer wall 630.

[0054] FIGS. 7A-7D show yet another implementation of an ear tip 704 that includes a body 720 configured to be attached to an earbud (e.g., earbud 102 of FIGS. 1A and 1B). The body 720 includes a first end 722 and a second end 724 opposite the first end 722. The body 720 further includes an inner wall 726 that extends between the first end 722 and the second end 724. The inner wall 726 defines and surrounds a hollow passage 728 configured to conduct sound waves. The inner wall 726 has an elongated cross-sectional shape, such as an ellipse, an oval, a racetrack shape (having parallel sides and rounded ends extending between the parallel sides, aka "stadium"), or an elongated shape with rounded ends and curved splines connecting them as shown in FIG. 7B. Here, "cross-section" or "cross-sectional" is to be understood as being perpendicular to the central axis of the inner wall 726. The body 720 also includes an outer wall 730 connected to the inner wall 726 at the first end 722. The outer wall 730 extends away from the inner wall 726 and towards the second end 724. In the illustrated example, the outer wall 730 is dome-shaped. However, other shapes, such as conical, are also contemplated.

[0055] The implementation modes shown in FIGS. 7A-7D utilize a viscoelastic material having frequency reinforcement behavior, such as a styrenic thermoplastic elastomer (TPE) having viscoelastic properties, for example, A9 TPE. A suitable A9 thermoplastic elastomer is available under the trade name GLS (trademark), product number LC AB5-741, from Avient (formerly PolyOne) of McHenry, Illinois. The viscoelastic material forms at least a portion of the inner wall 726 including at least a portion of an extension 742 extending between the outer wall 730 and the nozzle 108 and the first end 722 of the ear tip 704. The use of a material having frequency reinforcement behavior in this extension region provides improved passive attenuation performance in the frequency band of 1 kHz to 1.5 kHz compared to prior art ear tips using low durometer silicone in this region, although the low durometer silicone passes excessive noise. Since the material is viscoelastic, it has attenuation characteristics. It helps to attenuate impacts and shocks and vibrations and also helps with stability. Other suitable viscoelastic materials are described and claimed in U.S. Patent No. 10,623,846 entitled "Earpiece Employing Viscoelastic Materials", the complete disclosure of which is incorporated herein by reference.

[0056] For example, in some cases, the viscoelastic material may consist of a composition containing one or more elastomers, and the composition has a low-frequency elastic modulus measurement standard (Mlf) of about 0.5 to about 1, a high-frequency elastic modulus measurement standard (Mhf) of about 0.5 to about 1, and a glass transition temperature (Tg) of about -25°C to about 30°C. At least one of the one or more elastomers may be polynorbornene, polyurethane, styrenic thermoplastic elastomer, butyl rubber, acrylic, thermoplastic vulcanizate, nitrile rubber, etc. At least one of the one or more elastomers may be polynorbornene. The polynorbornene may have a density of about 0.8 to about 1.2 kg / dm3, a hardness of about 10 to about 20 Shore A, and a tensile strength of about 2 to about 8 MPa. The composition may include polynorbornene, antioxidant, UV stabilizer, curing agent, inhibitor, plasticizer, filler, etc. The Tg may be about 5°C to about 30°C. The Tg may be about 20°C to about 30°C. The Tg may be about 5°C to about 25°C. The Mhf may be about 0.7 to about 1. The Mlf may be about 0.7 to about 1. The product of Mhf and Mlf may be about 0.5 to about 1.

[0057] Viscoelastic materials, particularly TPEs, can be vulnerable to sebum. In that regard, the outer surface of the ear tip 704, for example, at least the outer surface of the outer wall 730, may be treated with a surface treatment such as electron beam treatment or photoionization to form a cross-linked matrix within the outer layer of the ear tip 704, such that the outer layer has a lower affinity for sebum than the inner layer (or untreated region(s)) of the ear tip 704. Additional details regarding the surface treatment are described and claimed in U.S. Patent No. 10,856,069, entitled "Sebum Resistance Enhancement for Wearable Devices", the complete disclosure of which is incorporated herein by reference.

[0058] The electron beam treatment performed on the TPE is the curing process. Once the TPE is molded into its desired shape, the electron beam treatment creates chemical cross-links in the material, which converts the material into a silicone-like state, providing excellent sebum and chemical resistance. This helps with sebum resistance and unlocks the ability to add a soft-touch topcoat over it. The electron beam treatment can also provide improved performance in many tests, including thermal shock.

[0059] In some implementations, at least the outer wall 730 of the ear tip 704 may be treated with a soft-touch coating such as that described and claimed in U.S. Patent Application No. 17 / 232479, entitled "Soft Touch Material," filed on April 16, 2021, the entire disclosure of which is incorporated herein by reference. For example, the TPE forming the outer wall 730 can be treated with a 50% poly(styrene-isobutylene-styrene) (SIBS) block copolymer / 50% silicone (wt / wt) soft-touch coating.

[0060] As described above, the electron beam treatment can enable the application of a soft-touch topcoat without damaging the part. The topcoat can be applied via spraying and then cured. In the process of applying the topcoat, the part (ear tip 704) is stressed with a solvent. Then, it is cured at a high temperature. All of this can stress the part. The electron beam treatment cross-links the part and increases its resistance to solvents and temperature.

[0061] The soft-touch coating can be applied anywhere the user will touch. The soft-touch topcoat provides a premium finish and helps with sealing and initial comfort. The soft-touch topcoat can also help with dust protection, as the A9 TPE material has a tendency to collect a lot of dust.

[0062] The viscoelastic material may also include cooling and sensation inducing materials as described and claimed in U.S. Patent No. 10,531,174, entitled "Earpiece Employing Cooling and Sensation Inducing Materials", the entire disclosure of which is incorporated herein by reference. For example, the viscoelastic material may include a composition comprising an elastomer, such as a styrenic TPE having viscoelastic properties, such as A9 TPE, and one or more phase change materials having the ability to change phase from a solid state to a liquid state at a predetermined phase change temperature, such as from about 25°C to about 35°C. The composition may have a hardness of from about 5 Shore A to about 50 Shore A, and the amount of the phase change material in the composition is from about 10 wt% to about 40 wt%.

[0063] In the embodiments shown in FIGS. 7A-7D, the viscoelastic material defines a retention mechanism 734, such as a protrusion, that extends around the inner surface of the inner wall 726 and engages a complementary retention mechanism 136, such as a recess, defined by and extending around the outer surface of the nozzle 108. The engagement of the retention mechanisms 734, 136 serves to hold the ear tip 704 on the nozzle 108 and also provides a good acoustic seal between the earbud 102 and the ear tip 704.

[0064] As shown in FIGS. 7B to 7D, the inner wall 726 is a ring 132 formed of a rigid plastic material such as glass-filled polyimide. The ring 726 is configured to engage the nozzle 108 to prevent rotation. In this regard, the ring 732 is adapted to the elongated shape of the nozzle 108, whereby when the ear tip 104 is attached to the nozzle 108, improper attachment of the ear tip is prevented. That is, the ring 732 ensures that the chip fits into the nozzle only when the chip is properly oriented with respect to the nozzle 108, and the elongated cross-sectional shapes of the ring 732 and the nozzle 108, together with the rigidity of the ring 732, help ensure that the ear tip 704 cannot rotate around the nozzle 108 once it is attached. As shown in FIG. 7B, the ring 732 can be in an oval shape, for example, a closed form (e.g., a closed loop) such as a racetrack shape. Alternatively, the ring 732 can be in an open form such as a C-shape having a gap that allows some compliance that enables the ring 732 to accommodate the nozzle 108. The gap can be filled with a viscoelastic material during the molding process in which the ear tip 704 is formed. In some cases, the ring 732 can be formed of two separate C-shaped members as shown in FIG. 5. In the embodiments of FIGS. 7A to 7D, both the ring 732 and the viscoelastic material form the inner wall 726.

[0065] The ear tip 704 can be formed in a two-shot molding process in which the ring 732 is first formed in a first molding step and then the remaining portion of the ear tip 704 (i.e., the remaining portions of the inner wall 726 and the outer wall 730) is formed in a second molding step.

[0066] Figures 8A - 8D illustrate another implementation of the ear tip 804 that includes a body 820 configured to be attached to an earbud (e.g., the earbud 102 of FIGS. 1A and 1B). The body 820 includes a first end 822 and a second end 824 opposite the first end 822. The body 820 further includes an inner wall 826 that extends between the first end 822 and the second end 824. The inner wall 826 defines and surrounds a hollow passage 828 that may be configured to conduct sound waves. The inner wall 826 has an elongated cross-sectional shape, such as an ellipse, an oval, a racetrack shape (having parallel sides and rounded ends extending between the parallel sides, also known as a "stadium"), or an elongated shape having rounded ends as shown in FIG. 8B and curved splines connecting them. Here, "cross-section" or "cross-sectional" should be understood to be perpendicular to the central axis of the inner wall 826. The body 820 also includes an outer wall 830 connected to the inner wall 826 at the first end 822. The outer wall 830 extends away from the inner wall 826 and towards the second end 824. In the illustrated example, the outer wall 830 has a dome-like shape. However, other shapes such as conical are also conceivable. As shown in FIG. 8C, the outer wall 830 extends beyond the second end 824. In an alternative implementation, the outer wall 830 may extend towards the second end 824 but not necessarily reach the second end 824.

[0067] The implementation shown in FIGS. 8A - 8D also utilizes a viscoelastic material having frequency reinforcement behavior, such as a styrenic TPE having viscoelastic properties, e.g., A9 TPE. The viscoelastic material may include any of the surface treatments or compounds described above with respect to FIGS. 7A - 7D.

[0068] As shown in FIGS. 8B - 8D, the ear tip 804 can include a ring 832 that engages the nozzle 108 to prevent rotation. In this regard, the ring 832 is adapted to the elongated shape of the nozzle 108, such that when the ear tip 804 is attached to the nozzle 108, improper attachment of the ear tip is prevented. Similar to the various embodiments described above, the ring 832 may be formed of a rigid plastic such as glass - filled polyimide.

[0069] As shown in FIGS. 8C and 8D, the ring 832 defines a recess 834 (e.g., an annular groove) that extends around the inner surface of the inner wall 826 and is configured to receive an O - ring 835 (e.g., a rubber O - ring) that seats within a corresponding recess 136 (e.g., an annular groove) formed on and extending around the outer surface of the nozzle 108. In this implementation, the engagement of the retaining mechanisms 834, 136 and the O - ring 835 helps to hold the ear tip 804 on the nozzle 108 and also provides a good acoustic seal between the earbud 102 and the ear tip 804.

[0070] As shown in FIGS. 8C and 8D, the ring 832 can also define a lip 837 that overlaps the end of the nozzle 108. The lip 837 can support a wax guard 838 (e.g., a screen that can be heat - staked to the lip 837). This can be an alternative to, or in addition to, the wax guard 840 (FIG. 8D) on the nozzle 108 itself.

[0071] Figures 9A-9D show another implementation of the ear tip 904 including a body 920 configured to be attached to an earbud (e.g., the earbud 102 of FIGS. 1A and 1B). The body 920 includes a first end 922 and a second end 924 opposite the first end 922. The body 920 further includes an inner wall 926 extending between the first end 922 and the second end 924. The inner wall 926 defines and surrounds a hollow passage 928 configured to conduct sound waves. The inner wall 926 has an elongated cross-sectional shape, such as an ellipse, an oval, a racetrack shape (having parallel sides and rounded ends extending between the parallel sides, also known as a "stadium"), or an elongated shape having rounded ends as shown in FIG. 9B and curved splines connecting them. Here, "cross-section" or "cross-sectional" should be understood to be perpendicular to the central axis of the inner wall 926. The body 902 also includes an outer wall 930 connected to the inner wall 926 at the first end 922. The outer wall 930 extends away from the inner wall 926 and towards the second end 924. In the illustrated example, the outer wall 930 is dome-shaped, however, other shapes such as conical are also contemplated. As shown in FIG. 9C, the outer wall 930 extends beyond the second end 924. In an alternative implementation, the outer wall 930 may extend towards the second end 924 but not necessarily reach the second end 924.

[0072] The embodiments shown in FIGS. 9A-9D also utilize a viscoelastic material having frequency reinforcement behavior, such as a styrenic TPE having viscoelastic properties, e.g., A9 TPE. The viscoelastic material may include any of the surface treatments or compounds described above with respect to FIGS. 7A-7D.

[0073] As shown in FIGS. 9B - 9D, the ear tip 904 can include a ring 932 that engages the nozzle 108 to prevent rotation. In this regard, the ring 932 is adapted to the elongated shape of the nozzle 108, thereby preventing improper attachment of the ear tip 904 when it is attached to the nozzle 108. Similar to the various embodiments described above, the ring 932 may be formed of a rigid plastic such as glass - filled polyimide. The ring 932 also extends outwardly from the inner surface of the inner wall 926 and defines one or more retention mechanisms 934, such as one or more protrusions, configured to engage a complementary retention mechanism 136, such as a recess, defined by the outer surface of the nozzle 108. The engagement of the retention mechanisms 934, 136 helps to hold the ear tip 904 on the nozzle 108.

[0074] The viscoelastic material defines a tapered portion 935 of the inner wall 926 that narrows the hollow passage 928 and tapers inwardly to provide an interference fit with the end of the nozzle 108. The interference 936 between the tapered portion 935 of the inner wall 926 and the nozzle 108 provides a good acoustic seal between the earbud 102 and the ear tip 904.

[0075] Figures 10A - 10F show yet another implementation of the ear tip 1004 configured to at least partially fit within a human ear canal. The ear tip 1004 includes a body 1020 configured to be mounted on the earbud 102. The body 1020 includes a first end 1022 and a second end 1024 opposite the first end 1022. The body 1020 further includes an inner wall 1026 extending between the first end 1022 and the second end 1024. The inner wall 1026 defines and surrounds a hollow passage 1028 that may be configured to conduct sound waves. The inner wall 1026 has an elongated cross-sectional shape, for example, elliptical, oval, a racetrack shape (having parallel sides and rounded ends extending between the parallel sides, also known as a "stadium"), or an elongated shape having rounded ends as shown in Figure 10B and curved splines connecting them. Here, "cross-section" or "cross-sectional" should be understood to be perpendicular to the central axis of the inner wall 1026. The body 1020 also includes an outer wall 1030 connected to the inner wall 1026 at the first end 1022. The outer wall 1030 extends away from the inner wall 1026 towards the second end 1024. In the illustrated example, the outer wall 1030 is dome-shaped, however, other shapes such as conical are also contemplated. As shown in Figure 10C, the outer wall 1030 extends beyond the second end 1024. In an alternative implementation, the outer wall 1030 may extend towards the second end 1024 but does not necessarily reach the second end 1024.

[0076] The embodiments shown in FIGS. 10A - 10E form an ear tip 1004 formed in a two - shot molding process using two different materials of different hardnesses. A first material, such as a high - durometer compliant material like high - durometer silicone, for example 60 Shore A - 80 Shore A silicone, such as 70 Shore A silicone, is used to form the inner wall 1026. The first material also defines a complementary retention mechanism 1036 that extends around the inner surface of the inner wall 1026 and engages a retention mechanism 1034, such as a protrusion, defined by and extending around the outer surface of the nozzle 1008. The engagement of the retention mechanisms 1034, 1036 serves to hold the ear tip 1004 on the nozzle 108 and provides a good acoustic seal between the earbud 1002 and the ear tip 1004.

[0077] The retention mechanism 1034 has two flat ends 1035 and two curved splines 1037 connecting them. The thickness t1 (FIG. 10C) of the spline 1037 is thicker than the thickness t2 (FIG. 10E) of the end 1035. As shown in FIG. 11, the recess 1036 on the nozzle 108 is similarly composed of two flat ends 1039 and two splines 1041 connecting them. The width w1 (FIG. 10D) of the recess 1036 along the spline 1037 is wider than the width w2 (FIG. 10F) along the flat end 1039 to accommodate the additional thickness of the spline 1041 of the protrusion 1034. Similarly, the width w2 of the recess 1036 along the flat end 1035 is sized to accommodate the flat end 1039 of the protrusion 1034. Thus, the respective shapes of the protrusion 1034 and the recess 1036 are fixed to each other so as to prevent improper attachment of the ear tip 1004 onto the nozzle 108 and to prevent rotation of the ear tip 1004 relative to the nozzle 108. The nozzle 108 of FIG. 11 is shown with an integral wax guard 1040.

[0078] The outer wall 1030 is formed around a high durometer material. The outer wall 1030 is formed of a low durometer material, for comfort, such as a low durometer silicone, such as a 10 Shore A to 30 Shore A silicone, such as a 20 Shore A silicone. The outer wall 1030 is the portion of the ear tip 1004 that contacts and conforms to the user's ear canal and forms an acoustic seal therebetween. In particular, as shown in FIG. 10A, the outer wall 1030 is in the shape of a dome having an elongated cross-sectional shape, such as an ellipse, an oval, or a racetrack shape (having parallel sides and rounded ends extending between the parallel sides, also known as a "stadium"). Here, "cross-section" or "cross-sectional" should be understood to be perpendicular to the central axis of the dome / outer wall 1030.

[0079] The ear tip 1004 can be formed by a two-shot molding process in which the inner wall 1026 is formed in a first molding step, followed by the formation of the outer wall 130 in a second molding step.

[0080] Throughout this specification, various examples have been described and illustrated. However, those skilled in the art will readily conceive of various other means and / or functions for performing and / or achieving the results and / or obtaining one or more of the advantages described herein, and each of these variations and / or modifications is considered to be within the scope of the examples described herein. More generally, those skilled in the art will readily understand that all of the parameters, dimensions, materials, and configurations described herein are exemplary, and that the actual parameters, dimensions, materials, and / or configurations will depend on the particular application or the application for which the teachings of the invention are used. Those skilled in the art will be able to recognize or confirm many equivalents corresponding to the specific examples described herein with only routine experimentation. Therefore, the foregoing examples are presented only by way of illustration, and it should be understood that the examples can be practiced in other ways than as explicitly described and claimed within the scope of the appended claims and their equivalents. The examples of the present disclosure are directed to each individual feature, system, article, material, kit, and / or method described herein. Furthermore, any combination of two or more of such features, systems, articles, materials, kits, and / or methods is included within the scope of the invention of the present disclosure, provided that such features, systems, articles, materials, kits, and / or methods are not mutually inconsistent.

Claims

1. An ear tip, comprising: a body configured to be attached to an earbud, the body including: a first end; a second end opposite the first end; an inner wall extending between the first end and the second end, the inner wall defining and surrounding a hollow passage configured to conduct sound waves; an outer wall connected to the inner wall at the first end and extending away from the inner wall toward the second end; the inner wall having an elongated cross-sectional shape configured to receive a corresponding nozzle on the earbud; the inner wall including a ring formed of a rigid material, the ring engaging and conforming to the elongated shape of the nozzle to prevent improper attachment of the ear tip to the nozzle and to prevent rotation of the ear tip relative to the nozzle when the ear tip is attached to the nozzle.

2. The inner wall further includes: a high-durometer compliant material defining at least a portion of an extension extending between the nozzle and the first end of the ear tip. The ear tip according to claim 1.

3. The outer wall is molded around the high-durometer compliant material and is formed of a lower-durometer compliant material. The ear tip according to claim 2.

4. The ring includes at least one C-shaped member having at least one gap, and the high-durometer compliant material is molded around the ring to fill the gap. The ear tip according to claim 2.

5. The ring includes a pair of C-shaped members arranged with a pair of gaps therebetween, and the high-durometer compliant material fills both gaps. The ear tip according to claim 4.

6. The high-durometer compliant material defines a retaining member configured to engage a mating retaining member on the nozzle. The ear tip according to claim 2.

7. The ring defines a recess extending around an inner surface of the inner wall and is configured to receive an O-ring seated within a corresponding recess formed on and extending around an outer surface of the nozzle. The ear tip according to claim 1.

8. The inner wall further includes an extension portion extending between the nozzle and the first end of the ear tip, and the outer wall and the extension portion are at least partially formed of a viscoelastic material having frequency reinforcement behavior. The ear tip according to claim 1.

9. The ear tip according to claim 8, wherein the extension portion and the outer wall are formed of a styrene-based TPE having viscoelastic properties.

10. The outer surface of the outer wall is treated with a surface treatment selected from electron beam treatment and photoionization to improve sebum resistance. The ear tip according to claim 8.

11. The outer surface of the outer wall has a soft-touch coating. The ear tip according to claim 8.

12. The soft-touch coating includes a 50% poly(styrene-isobutylene-styrene) (SIBS) block copolymer / 50% silicone (wt / wt) soft-touch coating. The ear tip according to claim 11.

13. The viscoelastic material includes a composition including an elastomer and one or more phase change materials having the ability to change phase from a solid state to a liquid state at a predetermined phase change temperature. The ear tip according to claim 8.

14. The predetermined phase change temperature is 25°C to 35°C. The ear tip according to claim 13.

15. The composition has a hardness of 5 Shore A to 50 Shore A, and the amount of the phase change material in the composition is 10% by weight to 40% by weight. The ear tip according to claim 13.

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