PATENT DOCUMENT

Publication Number: US-11012770-B2
Application Number: US-201916584940-A
Country: US
Kind Code: B2

Title: Eartips for in-ear listening devices

Abstract:
Embodiments describe an eartip including an eartip body having an attachment end and an interfacing end opposite from the attachment end, and including an inner eartip body and an outer eartip body. The inner eartip body has a sidewall that extends between the interfacing end and the attachment end, and includes a groove formed in an outer surface of the sidewall. The outer eartip body is sized and shaped to be inserted into an ear canal and extends from the interfacing end toward the attachment end of the eartip.

Claims:
What is claimed is: 
     
       1. An eartip, comprising:
 an eartip body having an attachment end and an ear interfacing end opposite from the attachment end, the eartip body formed from a compliant material and comprising: 
 an inner eartip body having a sidewall that defines a sound channel extending through the eartip body between the ear interfacing end and the attachment end; and 
 an outer eartip body integrally formed with the inner eartip body at the ear interfacing end and extending towards the attachment end around at least a portion of and in a spaced apart relationship with the inner eartip body, wherein the outer eartip body is sized and shaped to be inserted into an ear canal; and 
 wherein the inner eartip body includes a plurality of grooves formed in an outer surface of the sidewall with each groove in the plurality of grooves facing an inner surface of the outer eartip body. 
 
     
     
       2. The eartip of  claim 1 , wherein at least one groove in the plurality of grooves is defined by a base wall extending between two sidewalls. 
     
     
       3. The eartip of  claim 2 , wherein the base wall and at least one sidewall of the two sidewalls are arranged perpendicular to one another. 
     
     
       4. The eartip of  claim 1 , wherein the plurality of grooves includes a first groove and the inner eartip body includes a second groove spaced apart from the first groove along a length of the inner eartip body. 
     
     
       5. The eartip of  claim 1 , wherein the inner eartip body further comprises a boundary positioned between the interfacing end and the attachment end, and wherein the sidewall gradually changes in thickness from the first thickness to the second thickness from the boundary to the interfacing end. 
     
     
       6. The eartip of  claim 5 , wherein at least one groove in the plurality of grooves is defined by a base wall extending between two sidewalls having different lengths. 
     
     
       7. The eartip of  claim 1 , wherein at least one groove in the plurality of grooves extends around a circumference of the inner eartip body. 
     
     
       8. The eartip of  claim 1 , further comprising an internal sound sealing structure extending from the inner eartip body and positioned between the plurality of grooves and the attachment end. 
     
     
       9. The eartip of  claim 8 , wherein the internal sound sealing structure is a flange that extends toward the outer eartip body. 
     
     
       10. The eartip of  claim 1 , further comprising a support structure extending from the inner eartip body toward the outer eartip body. 
     
     
       11. The eartip of  claim 10 , wherein the support structure comprises a shell and an inner region filled with air. 
     
     
       12. The eartip of  claim 1 , further comprising an attachment structure coupled to the inner eartip body at the attachment end of the eartip body. 
     
     
       13. The eartip of  claim 1 , further comprising:
 a rigid attachment structure coupled to the inner eartip body at the attachment end, the rigid attachment structure defining a plurality of recesses and including a mesh extending across the sound channel. 
 
     
     
       14. The eartip of  claim 13 , wherein the plurality of grooves are positioned closer to the attachment end than the interfacing end. 
     
     
       15. The eartip of  claim 1  wherein the plurality of grooves form a bend region that mitigates potential kinking or buckling when the eartip is inserted into an ear canal. 
     
     
       16. The eartip of  claim 1  wherein a deflection zone is formed between the inner eartip body and the outer eartip body and wherein each groove in the plurality of grooves is open to the deflection zone. 
     
     
       17. The eartip of  claim 1  wherein at least one groove in the plurality of grooves formed in the outer surface of the sidewall extends around an entire perimeter of the inner eartip body. 
     
     
       18. An eartip, comprising:
 an eartip body having an attachment end and an interfacing end opposite from the attachment end, the eartip body comprising: 
 an inner eartip body having a sidewall extending between the interfacing end and the attachment end, the inner eartip body including a groove formed in an outer surface of the sidewall; and 
 an outer eartip body sized and shaped to be inserted into an ear canal and extending from the interfacing end toward the attachment end of the eartip; 
 wherein the groove is a first groove and the inner eartip body includes a second groove spaced apart from the first groove along a length of the inner eartip body and wherein the first groove and the second groove are positioned closer to the attachment end than the interfacing end. 
 
     
     
       19. An eartip, comprising:
 an eartip body having an attachment end and an ear interfacing end opposite from the attachment end, the eartip body formed from a compliant material and comprising: 
 an inner eartip body having a sidewall that defines a sound channel extending through the eartip body between the ear interfacing end and the attachment end; and an outer eartip body integrally formed with the inner eartip body at the ear interfacing end and extending towards the attachment end around at least a portion of and in a spaced apart relationship with the inner eartip body, wherein the outer eartip body is sized and shaped to be inserted into an ear canal; 
 a support structure extending from the inner eartip body toward the outer eartip body; and 
 wherein the inner eartip body includes a groove formed in an outer surface of the sidewall facing an inner surface of the outer eartip body; and 
 wherein the support structure comprises a plurality of flanges, each extending around the circumference of the inner eartip body and positioned across a majority of the length of the inner eartip body. 
 
     
     
       20. An in-ear listening device, comprising:
 a housing defining a cavity and an acoustic opening; 
 a driver positioned within the housing and operatively coupled to emit sound through the acoustic opening; and 
 an eartip removably attached to the housing and aligned with the acoustic opening, the eartip comprising: 
 an eartip body having an attachment end and an ear interfacing end opposite from the attachment end, the eartip body formed from a compliant material and comprising: 
 an inner eartip body having a sidewall that defines a sound channel extending through the eartip body between the ear interfacing end and the attachment end; and 
 an outer eartip body integrally formed with the inner eartip body at the ear interfacing end and extending towards the attachment end surrounding at least a portion of and in a spaced apart relationship with the inner eartip body, wherein the outer eartip body is sized and shaped to be inserted into an ear canal; and 
 wherein the inner eartip body includes a plurality of grooves formed in an outer surface of the sidewall with each groove in the plurality of grooves facing an inner surface of the outer eartip body. 
 
     
     
       21. The in-ear listening device of  claim 20 , wherein the eartip further comprises a rigid attachment structure coupled to the inner eartip body at the attachment end, the rigid attachment structure defining a plurality of recesses and including a mesh extending across the channel. 
     
     
       22. The in-ear listening device of  claim 20 , wherein at least one groove in the plurality of grooves is defined by a base wall extending between two sidewalls. 
     
     
       23. An eartip, comprising:
 an eartip body having an attachment end and an ear interfacing end opposite from the attachment end, the eartip body formed from a compliant material and comprising: 
 an inner eartip body having a sidewall that defines a sound channel extending through the eartip body between the ear interfacing end and the attachment end; and 
 an outer eartip body integrally formed with the inner eartip body at the ear interfacing end and extending towards the attachment end around at least a portion of and in a spaced apart relationship with the inner eartip body, wherein the outer eartip body is sized and shaped to be inserted into an ear canal; and 
 wherein the inner eartip body includes a plurality of grooves formed in an outer surface of the sidewall with each groove in the plurality of grooves extending around an entire perimeter of the inner eartip body and facing the inner surface of the outer eartip body.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application No. 62/823,592, filed on Mar. 25, 2019, the disclosure of which is hereby incorporated by reference in its entirety and for all purposes. 
    
    
     BACKGROUND 
     In-ear listening devices can be used with a wide variety of electronic devices such as portable media players, smart phones, tablet computers, laptop computers, stereo systems, and other types of devices. In-ear listening devices have historically included one or more small components configured to be placed in a user&#39;s ear, a driver that outputs sound through the component(s), and a cable that electrically connects the in-ear listening device to an audio source. Other in-ear listening devices can be wireless devices that do not include a cable and instead, wirelessly receive a stream of audio data from a wireless audio source. Such in-ear listening devices can include, for instance, wireless earbud devices or in-ear hearing devices that operate in pairs (one for each ear) or individually for outputting sound to, and receiving sound from, the user. For noise reduction, some in-ear listening devices can include an eartip that at least partially inserts into the user&#39;s ear canal. The eartip can direct sound outputted by the in-ear listening device through its sound channel and directly into the user&#39;s ear canal. 
     While eartips for wireless listening devices can improve noise reduction for some users, they also have some potential drawbacks. For example, eartips often improperly fit in a user&#39;s ear canal, which can cause discomfort for the user. Improperly fitting eartips can also result in a collapse of the sound channel, which can decrease acoustic performance and require the use of large drivers to compensate for lost performance. Implementing large drivers in wireless listening devices can result in a bulky in-ear listening device with poor battery life. 
     SUMMARY 
     Some embodiments of the disclosure provide an eartip for a wireless listening device that achieves improved comfort and acoustic performance, a smaller device footprint, and improved battery life, thereby resulting in an enriched user experience. The eartip is designed to easily bend and conform to a large variation of ear canal profiles so that the eartip can properly and comfortably fit in the ear canals of a vast majority of a user population without collapsing the sound channel. 
     In some instances, the eartip can include an eartip body formed of an inner eartip body and an outer eartip body. The inner eartip body can form the sound channel through which sound outputted by a driver in a housing of the wireless listening device can be outputted into an ear canal, and the outer eartip body can form an acoustic seal with the ear canal by bending and conforming to the contours of the ear canal. In certain embodiments, various modifications to the inner eartip body and an implementation of support structures for the outer eartip body can improve the eartip&#39;s fit in an ear canal to achieve improved comfort and acoustic performance for the user. As an example, the inner eartip body can include a series of grooves around a circumference of the inner eartip body to allow the inner eartip body to easily bend and conform to an ear canal profile without collapsing. Support structures can be implemented in vacant space between the inner eartip body and the outer eartip body to resist total deflection of the outer eartip body when the eartip is inserted into an ear canal. Configuring an eartip with the grooves and/or support structures can improve user comfort and acoustic performance, as well as decrease device size and increase battery life. 
     In some embodiments, an eartip includes an eartip body having an attachment end and an interfacing end opposite from the attachment end, the eartip body including an inner eartip body and an outer eartip body. The inner eartip body can have a sidewall that extends between the interfacing end and the attachment end, and can include a groove formed in an outer surface of the sidewall. The outer eartip body can be sized and shaped to be inserted into an ear canal and can extend from the interfacing end toward the attachment end of the eartip. 
     The groove can be defined by a base wall extending between two sidewalls. The base wall and at least one sidewall of the two sidewalls can be arranged perpendicular to one another. The groove can be a first groove and the inner eartip body can include a second groove spaced apart from the first groove along a length of the inner eartip body. The first groove and the second groove can be positioned closer to the attachment end than the interfacing end. The inner eartip body can further include a boundary positioned between the interfacing end and the attachment end, where the sidewall gradually changes in thickness from the first thickness to the second thickness from the boundary to the interfacing end. The groove can be defined by a base wall extending between two sidewalls having different lengths. The groove can extend around a circumference of the inner eartip body. The eartip can further include an internal sound sealing structure extending from the inner eartip body and positioned between the groove and the attachment end. The internal sound sealing structure can be a flange that extends toward the outer eartip body. The eartip can further include a support structure extending from the inner eartip body toward the outer eartip body. The support structure can include a plurality of flanges, each extending around the circumference of the inner eartip body and positioned across a majority of the length of the inner eartip body. The support structure can include a shell and an inner region filled with air. The eartip can further include an attachment structure coupled to the inner eartip body at the attachment end of the eartip body. 
     In some additional embodiments, an eartip includes an eartip body and an attachment structure. The eartip body includes an attachment end and an interfacing end opposite from the attachment end, and an inner eartip body that defines a channel that extends between the interfacing end and the attachment end, the inner eartip body including a groove formed in an outer surface of the sidewall. The attachment structure can be coupled to the inner eartip body at the attachment end, and can define a plurality of recesses and including a mesh extending across the channel. 
     The eartip body further can include an outer eartip body sized and shaped to be inserted into an ear canal and extending from the interfacing end toward the attachment end of the eartip. The groove can be defined by a base wall extending between two sidewalls. 
     In some further embodiments, an in-ear listening device includes: a housing defining a cavity and an acoustic opening; a driver positioned within the housing and operatively coupled to emit sound through the acoustic opening; and an eartip removably attached to the housing and aligned with the acoustic opening. The eartip includes an eartip body having an attachment end and an interfacing end opposite from the attachment end, the eartip body including an inner eartip body and an outer eartip body. The inner eartip body can have a sidewall that extends between the interfacing end and the attachment end, and can include a groove formed in an outer surface of the sidewall. The outer eartip body can be sized and shaped to be inserted into an ear canal and can extend from the interfacing end toward the attachment end of the eartip. 
     The eartip body can further include an attachment structure coupled to the inner eartip body at the attachment end, the attachment structure defining a plurality of recesses and including a mesh extending across the channel. The groove can be defined by a base wall extending between two sidewalls. 
     A better understanding of the nature and advantages of embodiments of the present invention may be gained with reference to the following detailed description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of an exemplary wireless listening device, according to some embodiments of the present disclosure. 
         FIG. 2A  is a side-view illustration of an exemplary wireless listening device where an eartip is attached to a housing, according to some embodiments of the present disclosure. 
         FIG. 2B  is a side view illustration of a wireless listening device where an eartip is detached from a housing, according to some embodiments of the present disclosure. 
         FIGS. 3A and 3B  are top-down view illustrations of exemplary eartips, according to some embodiments of the present disclosure. 
         FIG. 4  is a cross-sectional view illustration of an eartip attached to an outer structure of a housing via an attachment mechanism, according to some embodiments of the present disclosure. 
         FIGS. 5A and 5B  are cross-sectional view illustrations of an eartip when it is inserted into an ear canal, according to some embodiments of the present disclosure. 
         FIG. 6A  is a cross-sectional view of an exemplary eartip with a plurality of grooves formed in its inner eartip body, according to some embodiments of the present disclosure. 
         FIG. 6B  is a cross-sectional view illustration of the eartip of  FIG. 6A  when it is inserted into an ear canal, according to some embodiments of the present disclosure. 
         FIG. 6C  is a close-up cross-sectional view of an exemplary groove, according to some embodiments of the present disclosure. 
         FIG. 6D  is a top-down, cross-sectional view of an eartip across a horizontal plane that intersects a groove, according to some embodiments of the present disclosure. 
         FIGS. 7A-7C  are cross-sectional views of exemplary eartips having different configurations of grooves, according to some embodiments of the present disclosure. 
         FIGS. 8A-8E  is a cross-sectional view of an exemplary eartip configured with different internal sound outer eartip bodies, according to some embodiments of the present disclosure. 
         FIGS. 9A-9D  are simplified cross-sectional views of exemplary eartips implemented with coil guides for mitigating kinking, according to some embodiments of the present disclosure. 
         FIG. 10A  is a cross-sectional view of an exemplary eartip with a support structure configured as an annular or ovular balloon, according to some embodiments of the present disclosure. 
         FIG. 10B  is a cross-sectional view of the eartip in  FIG. 10A  after it has been inserted into an ear canal, according to some embodiments of the present disclosure. 
         FIGS. 11A-11B  are cross-sectional views of exemplary eartips including support structures having reinforcement components, according to some embodiments of the present disclosure. 
         FIGS. 12A-12B  are cross-sectional views of exemplary eartips having support structures configured as flanges, according to some embodiments of the present disclosure. 
         FIG. 12C  is a cross-sectional view of an exemplary eartip  1203  having support structures configured as springs, according to some embodiments of the present disclosure. 
         FIGS. 13A-13B  are cross-sectional views of an exemplary eartip including a dynamic outer eartip body in a sliding rod configuration, according to some embodiments of the present disclosure. 
         FIGS. 14A-14B  are top-down views of an exemplary eartip including a dynamic outer eartip body in a sliding plate configuration, according to some embodiments of the present disclosure. 
         FIGS. 15A-15B  are cross-sectional views of an exemplary eartip having an outer eartip body that extends from two regions of an inner eartip body to define an enclosed pocket, according to some embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Embodiments of the disclosure describe a wireless listening device that achieves improved user comfort and acoustic performance. The wireless listening device can be one of a pair of wireless listening devices configured to fit in the left and right ears of a user for outputting sound to the user. In some instances, the wireless listening device can include a housing and an eartip that can attach to the housing. The housing can include a rigid outer structure that encloses various electrical components that operate the wireless listening device (e.g., a battery, a processor, a driver for generating sound, and the like). The outer structure can include an opening through which the generated sound can be outputted to the eartip, which can then direct the sound into the user&#39;s ear canal. The eartip can be substantially pliable in construction but include a stiff attachment mechanism that enables the eartip to easily attach to the housing by inserting into the opening of the outer structure. 
     According to some embodiments, the eartip can be formed of an inner eartip body and an outer eartip body extending from an end of the inner eartip body. An inner diameter of the inner eartip body can form a sound channel through which sound can pass through from a driver in a housing of the listening device to a user&#39;s ear canal. An outer surface of the inner eartip body can include grooves that extend around at least a portion of the inner eartip body. The grooves can be evenly spaced apart along at least a portion of the length of the inner eartip body. Each groove can include a base wall and a pair of sidewalls that form a cavity in a surface of the inner eartip body when viewed from a cross-sectional perspective. The grooves can provide a degree of controlled bendability to the inner eartip body such that the inner eartip body resists kinking or sharp deformations when it conforms to the profile of the ear canal. 
     The eartip can also be configured to include support structures to help evenly distribute pressure against the ear canal when the wireless listening device is worn by the user. The support structures can be formed of a balloon structure, honeycomb structure, or one or more flanges. The support structures can be formed on an outer diameter of the inner eartip body or on an inner surface of the outer eartip body, as will be discussed further herein. The support structures can help mitigate the creation of pressure points against the ear canal when the wireless listening device is worn and help increase the surface area of contact between the outer eartip body and the ear canal surface, thereby improving comfort and acoustic performance. 
     As used herein, the term “in-ear listening device” includes any portable device designed to play sound directly into a user&#39;s ear canal to be heard by a user. In-ear listening devices can include an eartip that is attachable to a housing, which can be configured to generate sound into the eartip and be directed by the eartip into the ear canal. The term “eartip”, which can also be referred to as earmold, includes pre-formed, post-formed, or custom-molded sound-directing structures that at least partially fit within an ear canal. Eartips can be formed to have a comfortable fit capable of being worn for long periods of time. They can have different sizes and shapes to achieve a better seal with a user&#39;s ear canal and/or ear cavity, as will be discussed further herein. 
     I. Wireless Listening Device 
       FIG. 1  is a block diagram illustrating an exemplary wireless listening device  100 , according to some embodiments of the present disclosure. Wireless listening device  100 , as mentioned above, can include a housing  105 . Housing  105  can be an electronic device component that generates and receives sound to provide an enhanced user interface for a host device, such as a smart phone (not shown). Housing  105  can include a computing system  102  coupled to a memory bank  104 . Computing system  102  can execute instructions stored in memory bank  104  for performing a plurality of functions for operating housing  105 . Computing system  102  can be one or more suitable computing devices, such as microprocessors, computer processing units (CPUs), graphics processing units (GPUs), field programmable gate arrays (FPGAs), and the like. 
     Computing system  102  can also be coupled to a user interface system  106 , communication system  108 , and a sensor system  110  for enabling housing  105  to perform one or more functions. For instance, user interface system  106  can include a driver (e.g., speaker) for outputting sound to a user, microphone for inputting sound from the environment or the user, and any other suitable input and output device. Communication system  108  can include Bluetooth components for enabling housing  105  to send and receive data/commands from a host device (not shown). The host device, to which housing  105  is an accessory, can be a portable electronic device, such as a smart phone, tablet, or laptop computer. The host device can include a host communication system that can communicate with communication system  108  in housing  105  via a wireless communication line so that the host device can send sound data to housing  105  to output sound, and receive data from housing  105  to receive user inputs. Sensor system  110  can include optical sensors, accelerometers, microphones, and any other type of sensor that can measure a parameter of an external entity and/or environment. 
     Housing  105  can also include a battery  112 , which can be any suitable energy storage device, such as a lithium ion battery, capable of storing energy and discharging stored energy to operate housing  105 . The discharged energy can be used to power the electrical components of housing  105 . In some embodiments, battery  112  can also be charged to replenish its stored energy. For instance, battery  112  can be coupled to power receiving circuitry  114 , which can receive current from receiving element  116 . Receiving element  116  can electrically couple with a transmitting element  118  of an external charging device, such as a case (not shown). 
     According to some embodiments of the present disclosure, wireless listening device  100  can include an eartip  124 , and thus be configured as an in-ear hearing device. Eartip  124  can be specifically designed to achieve a comfortable fit in a user&#39;s ear canal while also achieving high acoustic performance, as will be discussed further herein. Eartip  124  can attach to, and detach from, housing  105  as shown in  FIGS. 2A and 2B . 
       FIG. 2A  is a side-view illustration of an exemplary wireless listening device  200  including a housing  202  and an eartip  204  attached to housing  202 , according to some embodiments of the present disclosure; and  FIG. 2B  is a side view illustration of wireless listening device  200  where eartip  204  is detached from housing  202 , according to some embodiments of the present disclosure. As shown in  FIG. 2A , eartip  204  can include a tip region  206  and a base region  208  that together form a monolithic structure, and a sound channel  210  that extends through both tip region  206  and base region  208 . Tip region  206  can include a curved, annular surface  207  that inserts into an ear canal for directing sound from housing  202  to the user, and can be formed of a pliable material that can easily bend to conform to the inner surfaces of the ear canal for forming an acoustic seal. Eartip  204  can be detached from housing  202 , as shown in  FIG. 2B , so that damaged eartips can be easily replaced or so that different types and/or sizes of eartips can be used to more comfortably fit in ear canals of different anatomical shapes and sizes. 
     In some embodiments, eartip  204  can have various profile shapes. For instance,  FIG. 3A  is a top-down view illustration of an exemplary eartip  300  configured with a circular profile, according to some embodiments of the present disclosure. When configured with a circular profile, eartip  300  can have a substantially circular outer diameter  302  and inner diameter  304 , which forms a circular sound channel  306 . Being configured with a circular profile enables eartip  300  to easily bend in all directions. However, some portions of ear canals may not have a substantially circular cross-sectional shape and thus may be difficult for eartip  300  to achieve a proper fit. Thus, in some embodiments, an eartip can be configured to have profiles configured in other shapes. 
       FIG. 3B  is a top-down view illustration of an exemplary eartip  301  configured with an ovular profile, according to some embodiments of the present disclosure. When configured with an ovular profile, eartip  301  can have a substantially ovular outer diameter  308  and inner diameter  310 , which forms an ovular sound channel  312 . The ovular profile allows eartip  301  to more easily conform to the natural shape of some portions of ear canals. However, the ovular profile may make it more difficult to bend eartip  301  in the vertical direction than it may be to bend eartip  301  in the horizontal direction. As will be appreciated from disclosures herein, a plurality of notches can be implemented in the construction of eartip  301  to improve bendability to achieve a proper fit in an ear canal. Furthermore, an eartip can have various other configurations that result in improved user comfort and sound quality. The details of such configurations and functionalities are discussed further herein. 
     II. Eartip Configurations 
       FIG. 4  is a cross-sectional view  400  of an exemplary eartip  402  attached to an outer structure  404  of a housing. Eartip  402  can include an inner eartip body  416  and an outer eartip body  422  that together form a monolithic structure. Inner eartip body  416  can be centered along a central axis  413  and define a sound channel  410  that extends through the entire length of eartip  402  between an ear-interfacing end  412  and an attachment end  414 . Sound channel  410  can be vacant space through which sound can travel from attachment end  414  to ear-interfacing end  412 . In some embodiments, attachment end  414  can be an end of eartip  402  that is configured to attach to outer structure  404  of the housing so that sound generated by the housing can pass into sound channel  410  through an acoustic opening  411  of outer structure  404 ; and, ear-interfacing end  412  can be an end of eartip  402  opposite from attachment end  414  that is configured to interface with (e.g., insert into) an ear canal of a user so that sound from the housing can be directed to the ear drum and thus be heard by the user. Ear-interfacing end  412  can face away from outer structure  404  when eartip  402  is attached to the housing and not worn by the user. When eartip  402  is attached to outer structure  404 , sound channel  410  can be substantially aligned with acoustic opening  411  of outer structure  404  so that sound the from the housing can easily propagate into sound channel  410 . 
     In some embodiments, eartip  402  can include a tip region  418  and a base region  420  (e.g., tip region  206  and base region  208  in  FIG. 2 ). Tip region  418  can be a part of eartip  402  that inserts into the ear canal of the user while base region  420  can be a part of eartip  402  that extends toward and attaches to outer structure  404  of the housing. Eartip  402  can also include an outer eartip body  422 . In some instance, outer eartip body  422  can be a part of tip region  418  that extends from, and is coupled to, inner eartip body  416  at ear-interfacing end  412  of eartip  402  toward attachment end  414 . Outer eartip body  422  can bend and conform to the contours of the ear canal to form an acoustic seal to prevent sound from entering the ear canal as ambient noise. Thus, according to some embodiments of the present disclosure, outer eartip body  422  can be formed of a thin, compliant material, e.g., silicone, thermoplastic urethane, thermoplastic elastomer, or the like, that can easily bend and deflect inward and outward to conform to various contours of the ear canal. To allow outer eartip body  422  to deflect inward and outward, outer eartip body  422  can be like a cantilever where its end closest to attachment end  414  is positioned a distance away from inner eartip body  416  to define a deflection zone  423  formed of vacant space within which outer eartip body  422  can freely deflect. In some additional and alternative embodiments, inner eartip body  416  can also be formed of the same material but of a different, e.g., larger, thickness so that a substantial portion of eartip  400  as a whole can be formed of the compliant material. Inner eartip body  416  can have a larger thickness than outer eartip body  422  because it does not contact the ear canal and provides some structural integrity to eartip  400 ; thus, it does not need to be as compliant as outer eartip body  422  for conforming to the ear canal. 
     Outer eartip body  422  can include a curved interface surface  424  that is configured to make contact with the inner surfaces of the ear canal for forming an acoustic seal when the wireless listening device is worn by the user. Outer eartip body  422  can taper toward ear-interfacing end  412  to make it easier for the user to insert eartip  402  into his or her ear canal. In some embodiments, a part of outer eartip body  422  closest to attachment end  414  can bend back toward inner eartip body  416  to reduce the chances of outer eartip body  422  flipping inside-out. 
     In some embodiments, eartip  402  can include an attachment structure  408  for securely attaching to outer structure  404 . As mentioned herein, eartip  402  can be formed of a compliant material such as silicone. Compliant materials may not easily attach to stiff structures alone. Thus, attachment structure  408  can be implemented to provide some rigidity for certain parts of eartip  402  to enable eartip  402  to securely attach to outer structure  404 . In some embodiments, attachment structure  408  is positioned within base portion  420  and may extend into a portion of tip portion  418  closest to attachment end  414  so that attachment structure  408  can help attach eartip  402  to outer structure  404  of the housing. Attachment structure  408  can be formed of a stiff, rigid material such as plastic or thermal plastic urethane (TPU) that is strong enough to achieve the desired attachment characteristics suitable for attaching eartip  402  with outer structure  404 . In some embodiments, attachment structure  408  is formed to be more rigid than inner eartip body  416  and outer eartip body  422 . 
     Attachment structure  408  can include a mesh  409  for preventing debris and other unwanted particles from falling into the housing through acoustic opening  411 . Mesh  409  can be an interlaced structure formed of a network of wire that allows sound to propagate through but prevents debris from passing through. In some embodiments, mesh  409  extends into a portion of attachment structure  408  so that mesh  409  can be securely fixed within eartip  402  by the rigid structure of attachment structure  408 . Attachment structure  408  can also include a plurality of attachment features  426  that protrude out of attachment end  404  and are configured to physically couple with outer structure  404 . In some instances, attachment features  426  can be separately positioned around a perimeter of attachment structure  408  so that attachment features  426  can attach to discrete locations of outer structure  404 . Each attachment feature  426  can include an arm and a hook that secures to outer structure  404 . 
     A. Grooves 
     According to some embodiments of the present disclosure, an eartip can be configured so that its inner eartip body resists collapsing when the wireless listening device is worn by a user. A collapsed inner eartip body can negatively impact acoustic performance and comfort, as discussed further herein.  FIGS. 5A and 5B  are cross-sectional views of an eartip when it is inserted into an ear canal, where the eartip is not properly designed to fit into the ear canal. Specifically,  FIG. 5A  is a cross-sectional view  500  of eartip  502  relative to an ear canal  504 , and  FIG. 5B  is a close-up cross-sectional view  501  of eartip  502  independent of ear canal  504 . As shown in  FIG. 5A , when inserted, eartip  502  can bend and conform to the inner surfaces of ear canal  504 . Housing  506  may not bend or conform when the wireless listening device, e.g., an in-ear hearing device, is worn by the user. In some instances where eartip  502  is not properly designed to fit into the ear canal, eartip  502  can collapse and/or create pressure points which can decrease acoustic performance and user comfort, as shown in  FIG. 5B . 
     For example, as shown in  FIG. 5B , improperly designed eartip  502  can kink or sharply deform at point  508  when it is inserted into ear canal  504 . When kinked, point  508  can excessively protrude into sound channel  510  and cause sound from housing  506  to reflect against inner eartip body  512  at abnormal angles and thus cause a decrease in acoustic performance. Furthermore, kinked eartip  502  can cause outer eartip body  514  to excessively bend and create pressure points in ear canal  504  when its interface surface  516  presses against surfaces of ear canal  504 , which can cause discomfort. 
     According to some embodiments of the present disclosure, an eartip can be designed to resist kinking or sharp deformations of its inner eartip body and instead, enable a gradual and smooth bending of its inner eartip body to avoid abnormal sound reflections and provide improved acoustic performance. The gradual bending can also mitigate the creation of pressure points against the ear canal to provide improved user comfort. For instance, the eartip can be designed with a series of grooves that are designed to provide a targeted degree of bendability across a broad region of the inner eartip body so that the inner eartip body can bend without forming a kink or sharp deformation, as discussed herein with respect to  FIGS. 6A-6C . 
       FIG. 6A  is a cross-sectional view of an exemplary eartip  600  with a plurality of grooves  602   a - c  formed in its inner eartip body  606 , according to some embodiments of the present disclosure. Like eartip  400 , eartip  600  can include an eartip body formed of an inner eartip body  606  and an outer eartip body  608  that together form a monolithic structure. Outer eartip body  608  can extend around a perimeter/circumference of inner eartip body  606  and during manufacturing, can initially be formed together as a deformable tube that is later folded over so that outer eartip body  608  is positioned outside of inner eartip body  606  as shown in  FIG. 6A . Inner eartip body  606  can be centered along a central axis and define a sound channel  610  that extends through inner eartip body  606  between an interfacing end  612  and an attachment end  614  of the eartip body. In some embodiments, attachment end  614  can be an end of the eartip body that is configured to attach to the housing via a nozzle and a wireform attachment feature so that sound generated by the housing can pass into sound channel  610  through an acoustic opening of the housing; and, interfacing end  612  can be an end of eartip  600  opposite from attachment end  614  where outer eartip body  608  begins to extend from inner eartip body  606 , such as a the top end of the eartip body. 
     Unlike eartip  400  in  FIG. 4 , however, eartip  600  can include grooves  602   a - c  positioned on an outer surface  616  of a sidewall of inner eartip body  606  facing an inner surface  618  of outer eartip body  608 . The sidewall of inner eartip body  606  can be defined by a portion of inner eartip body  606  disposed between a boundary  648  and interfacing end  612 . Boundary  648  can be an imaginary horizontal line positioned where inner eartip body  606  initially makes contact with attachment structure  642  as shown by a dashed and dotted line. Grooves  602   a - c  can be a series of grooves that form a bend region  605 , which can be a region that controls the bending of inner eartip body  606  and mitigates the occurrence of kinking or sharp buckling when eartip  600  is inserted into an ear canal. Each groove  602   a - c  can be a recess in the outer surface  616  of inner eartip body  606  that acts as a joint to promote a predetermined degree of bending at a specific location along inner eartip body  606 . While each groove can bend a small degree at a specific location, in the aggregate, grooves  602   a - c  can provide a plurality of bending points along the length of inner eartip body  606  that allows inner eartip body  606  to bend a larger degree. The spreading out and greater number of bend points can enable inner eartip body  606  to smoothly bend without kinking or sharply buckling, as shown in  FIG. 6B . 
       FIG. 6B  is a cross-sectional view illustration of eartip  600  when it is inserted into an ear canal, according to some embodiments of the present disclosure. Grooves  602   a - c  can provide a certain degree of bendability along bend region  605  instead of a single point. Thus, inner eartip body  606  of eartip  600  can have a large bend radius along bend line  611  that avoids kinking or sharp buckling of inner eartip body  606 . The large bend radius achieved by grooves  602   a - c  can allow inner eartip body  606  to bend so that its inner surface  604  stays smooth even while bent. That way, sound channel  610  stays intact and can provide improved acoustic performance over other eartips that do not have grooves. Each groove can be designed to achieve a certain degree of bendability, as will be discussed further herein with respect to  FIG. 6C . 
       FIG. 6C  is a close-up cross-sectional view of an exemplary groove, e.g., groove  602   c  in  FIG. 6A , according to some embodiments of the present disclosure. Groove  602   c  can include a base wall  620  positioned between two sidewalls  622  and  624  that together define a u-shaped recess  626  formed of vacant space. Recess  626  can provide a region where sidewalls  622  and  624  can bend into when ear-interfacing end  612  bends toward direction  628  (i.e., the direction groove  602   c  is facing) to fit in an ear canal. Conversely, recess  626  can provide a joint where sidewalls  622  and  624  bend away from one another when ear-interfacing end  612  bends toward direction  630  (i.e., opposite of the direction groove  602   c  is facing). In some embodiments, base wall  620  is perpendicular to sidewalls  622  and  624 , as shown in  FIG. 6A , when eartip  600  is not in an ear canal. However, embodiments are not limited to such configurations and that base wall  620  and sidewalls  622  and  624  can form respective acute or obtuse angles according to design. 
     Configuring base wall  620  and sidewalls  622  and  624  at acute angles, e.g., side wall configuration  621 , decreases the maximum bend angle when sidewalls  622  and  624  bend into recess  626  because sidewalls  622  and  624  may travel a shorter distance before running into one another when compared to a perpendicular arrangement, thereby resulting in a maximum bend angle for the inner eartip body that is less than that of the parallel configuration. Conversely, configuring base wall  620  and sidewalls  622  and  624  at obtuse angles, e.g., side wall configuration  623 , increases the maximum bend angle when sidewalls  622  and  624  bend into recess  626  because sidewalls  622  and  624  may travel a longer distance before running into one another when compared to a perpendicular arrangement, thereby resulting in a maximum bend angle for the inner eartip body that is greater than that of the parallel configuration. The maximum degree to which eartip  600  as a whole can bend may depend on the combined maximum bend angles of all grooves. Thus, the more each groove can bend, the more eartip  600  can bend as a whole. 
     In addition to the angle between base wall  620  and sidewalls  622  and  624 , other parameters of grooves  602   a - c  can be modified to alter the bend angle of eartip  600 . For instance, each groove can have a groove length  632  that spans across the length of base wall  620 . Longer groove lengths  632  can increase the maximum bend angle when sidewalls  622  and  624  bend into recess  626  because sidewalls  622  and  624  may be farther apart and thus may need to travel a longer distance before running into one another when compared to shorter groove lengths  632 . Shorter groove lengths  632  can decrease the maximum bend angle when sidewalls  622  and  624  bend into recess  626  because sidewalls  622  and  624  may be closer together and thus may need to travel a shorter distance before running into one another when compared to longer groove lengths  632 . Accordingly, those eartips designed with grooves having longer groove lengths  632  can achieve a greater degree of bending than that of other eartips designed with grooves having shorter groove lengths  632 . 
     In further addition to groove length  632  and the angle between base wall  620  and sidewalls  622  and  624 , separation distances between each groove  602   a - c  can be modified to achieve a certain bend radius. For instance, grooves  602   a - c  can be separated by separation distances  634   a - b , as shown in  FIG. 6A . Larger separation distances  634   a - b  can result in longer bend regions  605  and thus larger bend radiuses. Smaller separation distances  634   a - b  can result in shorter bend regions  605  and thus smaller bend radiuses. In some embodiments, separation distances  634   a - b  can be larger than the groove length of one or more grooves  602   a - c . In some additional and alternative embodiments, separation distances  634   a - b  can be smaller than or equal to the groove length of one or more grooves  602   a - c.    
     It is to be appreciated that the angles defined by base wall  620  and sidewalls  622  and  624 , in conjunction with groove lengths and separation distances, can allow eartips discussed herein to achieve a wide range of bend angles and bend radiuses. Specific ranges of bend angles and bend radiuses can be tailored according to design by configuring the angles, lengths, and distances discussed above. Accordingly, eartips of the present disclosure can be tuned to achieve a proper fit with at least 95% of the user population. Although discussions with respect to  FIG. 6C  relate to groove  602   c , it is to be appreciated that the discussions equally apply to grooves  602   a - b.    
     Although  FIG. 6C  shows base wall  620  as being substantially flat and vertical, embodiments are not so limited in that other embodiments can have modified base walls that have different profiles. For instance, base wall  620  can have a half-diamond profile  634  where base wall  620  is formed of two flat surfaces at different angles with respect to true north. The two surfaces can meet at one point in the center of base wall  620 . In another example, base wall  620  can have a half-hexagonal profile  636  where base wall  620  is formed of three flat surfaces at different angles with respect to true north. The center surface can be substantially vertical, i.e., parallel to true north, in such embodiments. In yet another example, base wall  620  can have a curved profile  638  where base wall  620  is formed of a curved surface. The curved surface can be a concave surface that follows the profile of a circle or an oval, and any other curved surface. Although the different profiles shown in  FIG. 6C  are symmetrical across a horizontal axis, embodiments are not limited to such configurations. In some embodiments, base wall  620  can have an amorphous profile  640  that is not symmetrical across a horizontal axis and have various curved surfaces of varying degrees of curvature. 
     In some embodiments, each groove  602   a - c  can extend along the entire perimeter of inner eartip body  606  so that eartip  600  can bend in any direction without kinking. For instance,  FIG. 6D  is a top-down, cross-sectional view  603  of eartip  600  across a horizontal plane that intersects groove  602   c , according to some embodiments of the present disclosure. Eartip  600  is shown with a circular cross-sectional profile but embodiments are not limited to such configurations. Some eartips can have oval or oblong cross-sectional profiles in other embodiments as shown in  FIG. 3B  herein. With reference to  FIG. 6C , groove  602   c , and grooves  602   a - b  even though they are not shown in  FIG. 6C , can have an ovular structure that extends along a circumference of inner eartip body  606 . The outer surface of inner eartip body  606  is shown as a dotted line to indicate its position relative to bottom wall  620  of groove  602   c . By being formed with ovular profiles, grooves  602   a - c  can be have a corresponding ovular profile and provide improved bendability and resistance to kinking for eartip  600  in all directions. This may help eartip  600  more easily fit into ear canals by requiring less force to bend along the ear canal profile, which can further improve usability and comfort. In instances where eartip  600  has a circular profile, grooves  602   a - c  can have annular profiles that also provide the improved bendability and resistance to kinking for eartip  600  equally in all directions. 
     Although  FIG. 6D  illustrates grooves extending around an entire circumference of an inner eartip body, other embodiments are not so limited and can have grooves that extend around a portion of the inner eartip body. That way, only specific portions of the eartip can have the bendability provided by the grooves. This may be particularly useful in instances where the eartip is ovular and is more likely to bend along its long axis than its short axis. In such cases, grooves can extend around a portion of the inner eartip body positioned on a region of the outer surface along the long axis. 
     The thickness of an inner eartip body of an eartip can affect the bendability of the eartip. Thicker inner eartip bodies can require more force to bend the eartip, while thinner inner eartip bodies can require less force. Thus, thicker inner eartip bodies can resist deformation more than thinner inner eartip bodies, thereby causing the eartip to feel harder and potentially more uncomfortable to the user. In some embodiments, the inner eartip body of an eartip can have a thickness that is substantially constant across its length, as shown in  FIG. 4 . In such configurations, the eartip may have the same feel and firmness to it regardless of where it bends. However, in some other embodiments, the inner eartip body can have varying thicknesses to achieve a softer feel in some parts of the eartip and firmness in other parts. For instance, with reference to  FIG. 6A , inner eartip body  606  can have a thickness that gradually changes from ear-interfacing end  612  to attachment end  614 . In certain embodiments, the thickness of inner eartip body  606  can gradually increase from ear-interfacing end  612  to attachment end  614  so that eartip  600  can have varying degrees of mechanical compliance at different points along its length. For instance, having a thinner inner eartip body near ear-interfacing end  612  (i.e., the end that inserts into an ear canal) gives eartip  606  a more soft and comfortable construction, while having a thicker inner eartip body near attachment end  614  gives eartip  606  a firmer construction that provides more structural rigidity for attaching to a housing. This allows eartip  600  to achieve a robust attachment to the housing without compromising its soft, comfortable feel for the user. 
     In such embodiments where the thickness of inner eartip body  606  varies, the sidewalls of each groove can have different lengths to follow the slanted profile of outer surface  616  of inner eartip body  606 . As an example, the length of sidewall  622  in  FIG. 6C  can be shorter than the length of sidewall  624 , while base wall  620  is substantially vertical. Furthermore, in certain embodiments, the depth of grooves  602   a - c  can vary along with the thickness of inner eartip body  606 . For example, grooves closest to ear-interfacing end  612  (e.g., groove  602   a ) can have shallower depths than grooves farther from ear-interfacing end  612  (e.g., grooves  602   b - c ). Thus, in some embodiments, the sidewall lengths of grooves closest to ear-interfacing end  612  can be shorter than those of grooves farther from ear-interfacing end  612 . Such configurations may have the same inner eartip body  606  thickness at regions proximate to the base walls of grooves  602   a - c , as shown in  FIG. 6A . Alternatively, grooves  602   a - c  can have the same depths. In such instances, grooves  602   a - c  can have the same sidewall lengths. By having the same depths, each groove can bend the same degree. 
     With reference back to  FIG. 6A , in some embodiments, eartip  600  can include an attachment structure  642  for coupling with a housing. Attachment structure  642  can include an upper region  643  and a lower region  645  that extends from upper region  643 . Upper region  643  can have a more horizontal disposition than lower region  645 , which may be more vertical than upper region  643 , thereby being an inverted u-shaped profile as shown. Unlike attachment structure  408  in  FIG. 4  which has features that actively grip onto the housing, attachment structure  642  instead includes recesses  644   a - b  around lower region  645  for providing latching points for an attachment mechanism to attach. Recesses  644   a - b  can be cavities defined by an inner surface  646  of lower region  645  of attachment structure  642  that passively allow an attachment mechanism to secure eartip  600  to a housing. For instance, portions of the lower region below recesses  644   a - b  can form an inverted overhang structure that hooks onto an external structure, such as an end cap of an attachment structure. Inner eartip body  606  can interface with attachment structure  642  at boundary  648 . 
     Attachment structure  642  can be formed of a different and stiffer material than what is used to construct the eartip body. Attachment structure  642  can be formed of a stiffer material so that its rigidity can be more suitable for attaching to the housing. Eartip  600  can also include a mesh  650  for preventing debris and other unwanted particles from falling completely through sound channel  610 . Mesh  650  can be a soft, porous fabric that allows sound to propagate through but prevents debris from passing through. For instance, mesh  650  can be formed of a polyester fabric. In some embodiments, mesh  650  extends into upper region  643  of attachment structure  642  so that mesh  650  can be securely fixed within eartip  600  by the rigid structure of attachment structure  642 . 
     Although  FIG. 6A  shows an eartip having three grooves positioned near the bottom of the inner eartip body, embodiments are not limited to such configurations and that eartips having any number of grooves positioned along any region of the length of the inner eartip body are envisioned herein without departing from the spirit and scope of the present disclosure.  FIGS. 7A-7C  are cross-sectional views of exemplary eartips having different configurations of grooves, according to some embodiments of the present disclosure. In some embodiments, an eartip  700  in  FIG. 7A  can have two grooves  702   a - b  that are positioned closer to ear-interfacing end  710  than attachment end  712 . Accordingly, the bend region can be near ear-interfacing end  710  and can allow eartip  700  to bend to fit the profile of an ear canal without kinking or sharply deforming. Although  FIG. 7A  shows grooves  702   a - b  closer to ear-interfacing end  710  than attachment end  712 , embodiments can have grooves  702   a - b  closer to attachment end  712  than ear-interfacing end  710 . In some additional or alternative embodiments, an eartip  701  in  FIG. 7B  can have a single groove  704  that is positioned closer to attachment end  712  than ear-interfacing end  710 . Accordingly, the bend region can be near attachment end  712  and allow eartip  701  to bend to fit the profile of an ear canal without kinking or sharply deforming. And, in some additional or alternative embodiments, an eartip  703  in  FIG. 7C  can have four grooves  706   a - d  that are positioned along the entire length of inner eartip body  708  between attachment end  712  and ear-interfacing end  710 . Thus, the entire length of eartip  700  can bend to fit the profile of an ear canal without kinking or sharply deforming. 
     B. Internal Sound Sealing Structures 
     As disclosed herein, a plurality of grooves can be formed along a region of an inner eartip body of an eartip to promote bending without kinking or sharply deforming. By forming the grooves, the thickness of the region of the inner eartip body where the grooves are positioned may be thinner than regions where grooves are not present. For instance, with brief reference back to  FIG. 7A , the region where grooves  702   a - b  are positioned may be thinner than other regions of inner eartip body  708 . The thin regions may sometimes allow sound  714  to travel between sound channel  716  and deflection zone  718 , thereby causing interference and/or a decrease in acoustic performance. As an example, ambient noise existing in the surrounding environment can leak through the thin region and into sound channel  716  from deflection zone  718  of eartip  700  and be heard by the user as interference, e.g., pink noise. Furthermore, sound outputted to the user from the housing through sound channel  716  can leak through the thin region and into the atmosphere through deflection zone  718 , thereby attenuating the audio output from the housing and reducing the acoustic performance of the system. According to some embodiments of the present disclosure, one or more internal sealing structures can be implemented to prevent and/or mitigate the transmission of this interference to the user. The internal sealing structure can be any suitable structure configured to seal the deflection zone from atmosphere when the eartip is inserted into an ear canal, as will be discussed further herein. 
       FIG. 8A  is a cross-sectional view of an exemplary eartip  800  configured with an internal sound outer eartip body  802 , according to some embodiments of the present disclosure. Internal sound outer eartip body  802  can be an annular or ovular shaped flange that extends around, and be directly attached to, an entire circumference of inner eartip body  804 . Internal sound outer eartip body  802  can also include an end  803  that extends into deflection zone  806  toward outer eartip body  808 . In some embodiments, internal sound outer eartip body  802  can extend at a downward angle as shown in  FIG. 8A  toward attachment end  814 . End  803  can freely suspend in space and be separated from outer eartip body  808  when eartip  800  is not inserted into an ear canal. However, when eartip  800  is inserted into an ear canal, outer eartip body  808  may make contact with internal sound outer eartip body  802  and form a seal that seals deflection zone  806  from the atmosphere. That way, sound can be prevented from leaking between sound channel  810  and deflection zone  806  through the thin regions of inner eartip body  804  where grooves  812   a - b  are positioned, thereby mitigating interference and improving acoustic performance. In some embodiments, internal sound outer eartip body  802  is positioned closer to attachment end  814  than all of the grooves, e.g., grooves  812   a - b . Furthermore, in certain embodiments, internal sound outer eartip body  802  can be an extension of inner eartip body  804  such that inner eartip body  804  and internal sound outer eartip body  802  form a monolithic structure. However, in other embodiments, internal sound outer eartip body  802  and inner eartip body  804  can be independent structures where internal sound outer eartip body  802  is attached to inner eartip body  804  by an adhesive (not shown) or any other suitable means, e.g., mechanical fastening, geometric fastening, static friction, and the like. 
     It is to be appreciated that although  FIG. 8A  shows an internal sealing structure formed of a single flange extending from the inner eartip body and into the deflection zone, embodiments are not limited to such configurations. Other embodiments can have internal sealing structures formed of more than one flange and/or attached to different parts of the eartip, or they can be formed of an inner eartip body, as discussed herein with respect to  FIGS. 8B-8E . 
       FIGS. 8B-8E  illustrate several eartips having internal sound sealing structures that are configured in different ways, according to some embodiments of the present disclosure. For instance,  FIG. 8B  illustrates an exemplary eartip  801  that includes a plurality of internal sound outer eartip bodies, e.g., flanges  816  and  818 . Like internal sound outer eartip body  802 , both outer eartip bodies  816  and  818  can be annular or ovular structures that extend into deflection zone  806  toward outer eartip body  808  at a downward angle. Furthermore, both outer eartip bodies  816  and  818  can extend around, and be attached to, an entire circumference of inner eartip body  820 . 
     In some embodiments, internal sound sealing structures may be flanges that extend upward. For instance,  FIG. 8C  illustrates an exemplary eartip  803  that includes an internal sound outer eartip body  822  that, like internal sound outer eartip body  802  in  FIG. 8 , can be an annular or ovular structure that extends into deflection zone  806  toward outer eartip body  808 ; and it can also extend around, and be attached to, an entire circumference of inner eartip body  820 . However, unlike flange  802 , internal sound outer eartip body  822  can extend at an upward angle, as shown in  FIG. 8C . Extending at an upward angle can ensure that flange  822  does not slide so far along outer eartip body  808  that it ends up extending below a bottom end  821  of outer eartip body  808 . 
     Although embodiments discussed herein with respect to  FIGS. 8B-8C  have internal sound outer eartip bodies that extend from, and are directly attached to, the inner eartip body, embodiments are not limited to such configurations. For instance,  FIG. 8D  illustrates an exemplary eartip  805  that includes an internal sound outer eartip body  824  that, like internal sound outer eartip body  802 , can be an annular or ovular structure that extends into deflection zone  806  at a downward angle, as shown in  FIG. 8D . However, unlike flange  802 , internal sound outer eartip body  822  can extend around, and be directly attached to, an entire inner circumference of outer eartip body  808 . Flange  822  can also extend toward inner eartip body  820 . 
     It is to be appreciated that while an internal sound sealing structure can be formed of a flange that contacts another structure form a seal, embodiments are not limited to such configurations. For instance, some embodiments can be formed of other structures for forming a seal without departing from the spirit and scope of the present disclosure.  FIG. 8E  illustrates an exemplary eartip  807  that includes an internal sound sealing structure that is formed of an annular bulbous structure  826 , according to some embodiments of the present disclosure. Bulbous structure  826  can include a flat surface that attaches to inner eartip body  820  and a convex surface that extends toward outer eartip body  808 , as shown in  FIG. 8E . Bulbous structure  826  can be an extension of inner eartip body  820  such that structure  826  and inner eartip body  820  form a monolithic structure. Alternatively, bulbous structure  826  and inner eartip body  820  are independent structures where bulbous structure  826  is attached to inner eartip body  820 . Bulbous structure  826  can be formed of any suitable material that can form a seal between inner eartip body  820  and outer eartip body  808 . For instance, bulbous structure  826  can be formed of a sticky material that can securely, but temporarily, stick to outer eartip body  808  when eartip  807  is inserted into an ear canal. In another instance, bulbous structure  826  can be formed of a soft and malleable material with a lower density and durometer than the material used to form inner eartip body  820  and/or outer eartip body  808 . The contact formed between bulbous structure  826  and both inner eartip body  820  and outer eartip body  808  can form an acoustic seal. In certain embodiments, the material used to formed bulbous structure  826  can be different from the material used to form inner eartip body  820  and/or outer eartip body  808 . In some alternative embodiments, bulbous structure  826  may be laterally flipped and directly attached to outer eartip body  808  instead, similar to the configuration shown in  FIG. 8D  for internal sound outer eartip body  824 . 
     In some other embodiments, an internal sound sealing structure (not shown) can be permanently attached between the inner eartip body and the outer eartip body to permanently seal the deflection zone (as well as the sound channel) from the atmosphere. In such instances, the internal sound outer eartip body can be formed of a soft and compliant material that can easily collapse to allow the outer eartip body to deflect into the deflection zone when the eartip is worn. Alternatively, a compliant, foam-like material can completely fill in the vacant space in the deflection zone. The foam-like material can prevent sound from leaking between the sound channel and the deflection zone through the thinner wall of the inner eartip body. 
     C. Coil Guide 
     Although  FIGS. 6A-6D, 7A-7C, and 8A-8E  illustrate exemplary eartips having grooves formed in the inner eartip body, embodiments are not limited to such configurations to mitigate kinking in the inner eartip body. For instance, a coil guide can be implemented by an eartip to help guide the bending motion of the inner eartip body and mitigate kinking, as discussed herein with respect to  FIGS. 9A-9D . 
       FIGS. 9A-9D  are simplified cross-sectional views of exemplary eartips implemented with coil guides for mitigating kinking, according to some embodiments of the present disclosure. As shown in  FIG. 9A , an eartip  900  can include a coil guide  902  wound around an inner eartip body  904  of eartip  900 . Coil guide  902  can be a strand of wire wound into a spiral shape positioned outside of inner eartip body  904 . In some embodiments, coil guide  902  can contact an outer surface  906  of inner eartip body  904  and be positioned on the sidewall of inner eartip body  904  between a boundary  908  and an interfacing end  910  of eartip  900 . Boundary  908  and interfacing end  910  are similar to boundary  648  and interfacing end  612  discussed herein with respect to  FIG. 6A  and are thus not discussed here for brevity. In some embodiments where inner eartip body  904  has a varying sidewall thickness between boundary  908  and interfacing end  910 , coil guide  902  can be conical in shape and thus have turns near boundary  908  that have larger diameters than turns near interfacing end  910 . Each consecutive turn from a turn closest to boundary  908  to a turn closest to interfacing end  910  can decrease in diameter and at a same degree of difference across all turns, thereby forming a conical shape with an angled and linear tangential profile  907  extending along a height of coil guide  902 . That way, coil guide  902  conforms to the tapering profile of the sidewall of inner eartip body  904 . 
     As shown in  FIG. 9B , an exemplary eartip  901  can have a coil guide  912  embedded within a sidewall of inner eartip body  914 . Like coil guide  902 , coil guide  912  can be conical in shape and thus have turns near boundary  908  that have larger diameters than turns near interfacing end  910 . In some embodiments, coil guide  912  can be positioned closer to an outer surface  916  of the sidewall of inner eartip body  914  than an inner surface  918  of inner eartip body  914 . 
     Although  FIGS. 9A-9B  show embodiments where coil guides have conical shapes and are positioned on outer surfaces of, and within, the inner eartip body, embodiments are not so limited. Other embodiments can have substantially cylindrical shapes and be positioned on inner surfaces of, and within, the inner eartip body. For instance, as shown in  FIG. 9C , an exemplary eartip  903  can include a coil guide  920  positioned on an inner surface  922  of a sidewall of an inner eartip body  924 . Coil guide  920  can be substantially cylindrical in shape and thus all of the turns of coil guide  920  can have equal diameters. That is, all the turns of coil guide  920  can have the same diameter, thereby forming a cylindrical shape with a vertical and linear tangential profile  923  extending along a height of coil guide  920 . 
     As shown in  FIG. 9D , an exemplary eartip  905  can have a coil guide  926  embedded within a sidewall of an inner eartip body  928 . Like coil guide  920 , coil guide  926  can be cylindrical in shape and thus all the turns can have equal diameters. In some embodiments, coil guide  926  can be positioned closer to an inner surface  930  of the sidewall of inner eartip body  928  than an outer surface  932  of inner eartip body  928 . 
     By incorporating a coil guide into eartips, inner eartip bodies may have more structural rigidity yet have a sufficient degree of bendability to bend and conform to the profile of an ear canal while being more resistant to kinking. 
     D. Support Structures 
     When inserted into an ear canal, the outer eartip body can conform to the inner surfaces of the ear canal and form a seal. Some surfaces of the ear canal can cause the outer eartip body to unevenly press against the ear canal, which can create pressure points and cause discomfort. Additionally, only a small portion of the outer eartip body may make contact with the ear canal, thereby forming a weak seal that can allow noise from the environment to interfere with sound outputted by the housing. Thus, according to some embodiments of the present disclosure, one or more support structures can be implemented to resist uneven deformation of the outer eartip body so that pressure is spread evenly across the inner surface of the ear canal, thereby mitigating the creation of pressure points to improve comfort and acoustic seal, as will be discussed further herein. 
       FIG. 10A  is a cross-sectional view of an exemplary eartip  1000  with a support structure  1002  configured as an annular or ovular balloon, according to some embodiments of the present disclosure. Support structure  1002  can include a contact surface  1005  and a flat surface  1003  that attaches to, and around the entire circumference of, inner eartip body  1004 . Contact surface  1005  can be curved, as shown in  FIG. 10A , or any other suitable contour, such as straight or angled, without departing from the spirit and scope of the present disclosure. Support structure  1002  can be configured so that when eartip  1000  is not inserted into an ear canal, support structure  1002  may not make contact with inner surface  1008  of outer eartip body  1006 , but does make contact when eartip  1000  is inserted into an ear canal. In some embodiments, at least a portion of contact surface  1005  is configured to make contact with outer eartip body  1006  when eartip  1000  is inserted into an ear canal. When inserted, support structure  1002  can be designed to resist the complete collapse of outer eartip body  1006  of eartip  1000 . Support structure  1002  can resist the collapse by pressing against an inner surface  1008  of outer eartip body  1006  along a force vector opposite to that applied by the ear canal to deflect outer eartip body  1006  into deflection zone  1010 , which is better shown in  FIG. 10B . 
       FIG. 10B  is a cross-sectional view of eartip  1000  with support structure  1002  after it has been inserted into an ear canal, according to some embodiments of the present disclosure. When outer eartip body  1006  deflects into deflection zone  1010 , support structure  1002  can resist the deflection of inner surface  1008  of outer eartip body  1006  and press against flat surface  1003  to evenly spread out the resisting pressure across a majority of inner surface  1008 . That way, outer eartip body  1006  can resist small bends that form pressure points against an ear canal, which can cause discomfort to a user. To enable the spreading of pressure across inner surface  1008  of outer eartip body  1006 , support structure  1002  can be configured to make contact with a majority (i.e., greater than half) of a surface area of inner surface  1008 . One way to do this is to have a broad contact surface  1005 . Accordingly, support structure  1002  can have an elongated structure that is attached to a majority of a length of inner eartip body  1004 , as shown in  FIGS. 10A and 10B . 
     In some embodiments, support structure  1002  is formed as a balloon including a shell  1012  that defines an inner region  1014 . Shell  1012  can be formed of any suitable compliant material, such as silicone. Shell  1012  and inner eartip body  1014  can form a monolithic structure in some embodiments, or be formed of independent structures that are attached via an adhesive, mechanical fastener, geometric fastener, static friction, and the like in other embodiments. Inner region  1014  can be vacant space that is filled with air, or any other suitable material such as a liquid (e.g., water, oils, and the like) or a porous and compliant structure (e.g., foam or honeycomb material). To help resist the total collapse of outer eartip body  1006 , one or more reinforcement components can be implemented in support structure  1002 , as shown in  FIGS. 11A and 11B . 
       FIGS. 11A and 11B  are cross-sectional views of exemplary eartips  1100  and  1101  including support structures  1102  and  1104  having reinforcement components  1106  and  1108   a - b , respectively, according to some embodiments of the present disclosure. Reinforcement component  1106  of support structure  1102  can be a ring that extends around a circumference of inner eartip body  1103  and completely through the inner region to separate it into two inner regions  1110   a - b . Similarly, reinforcement components  1108   a - b  of support structure  1104  can be rings that extend around a circumference of inner eartip body  1103  and completely through the inner region to separate it into three inner regions  1112   a - c . Reinforcement components  1106  and  1108   a - b  can provide additional resistance against the total collapse of outer eartip body  1105 . In some embodiments, reinforcement component  1106  is positioned at the center of support structure  1102 , and reinforcement components  1108   a - b  are positioned to be equally spaced apart from each other and the opposing far ends (lengthwise) of support structure  1104 , so that reinforcement components  1106  and  1108   a - b  can be positioned evenly along the length of respective support structures  1102  and  1104  to resist the deflection of outer eartip body  1105  evenly along the length of support structures  1102  and  1104  and improve the amount of surface area that contacts the inner surfaces of an ear canal. It is to be appreciated that additional reinforcement components can be added to provide additional assistance against the collapsing of outer eartip body  1105  and for providing a spreading of pressure against the surfaces of the ear canal. 
     While  FIGS. 11A and 11B  discuss reinforcement components  1106  and  1108   a - b  as rings, embodiments are not limited to such configurations. Other embodiments can have reinforcement components that are formed as posts that are evenly distributed around the inner region to spread the pressure against the surfaces of the ear canal. Any suitable configuration of reinforcement components in-line with the spirit and scope of the present disclosure to spread pressure and maximize the amount of surface area contacting the inner surfaces of an ear canal are envisioned herein. 
     Although  FIGS. 10A-10B and 11A-11B  illustrates support structures having an inner eartip body-like construction that includes a shell and an inner region, embodiments are not limited to such configurations. For instance, other embodiments can include support structures that may not be formed of a shell and an inner region, but are instead completely formed of a solid, compliant structure. For instance, support structure  1002  in  FIG. 10A  can be a solid structure formed of a foam or honeycomb material. In other instances, support structures can be constructed as flanges or springs, as discussed herein with respect to  FIGS. 12A-12C . Specifically,  FIGS. 12A and 12B  are cross-sectional views of exemplary eartips  1200  and  1201  having support structures configured as flanges, and  FIG. 12C  is a cross-sectional view of an exemplary eartip  1203  having support structures configured as springs, according to some embodiments of the present disclosure. These support structures can be configured to resist uneven deformation of the outer eartip body so that pressure is spread evenly across the inner surface of the ear canal, thereby mitigating the creation of pressure points to improve comfort and acoustic seal. 
     As shown in  FIG. 12A , eartip  1200  can include a plurality of support structures  1202   a - d  constructed as flanges that extend from an inner surface  1204  of outer eartip body  1206  toward inner eartip body  1208  without making contact with inner eartip body  1208  until eartip  1200  is inserted into an ear canal. Each support structure  1202   a - d  can be similar in construction and configuration to internal sound outer eartip body  824  except that support structures  1202   a - d  may be positioned evenly along a length of inner surface  1204  so that support structures  1202   a - d  can provide resistive force across a majority, if not the entire, length of inner surface  1204 . 
     Alternatively, support structures can be configured as flanges that extend from the inner eartip body of an eartip, as shown in  FIG. 12B . For example, eartip  1201  can include a plurality of support structures  1212   a - c  constructed as flanges that that extend from an outer surface  1210  of inner eartip body  1208  toward inner surface  1204  of outer eartip body  1206  without making contact with inner surface  1204  until eartip  1200  is inserted into an ear canal. Support structures  1212   a - c  can be positioned evenly along a length of outer surface  1210  of inner eartip body  1208  so that support structures  1212   a - c  can provide resistive force across a majority, if not the entire, length of inner surface  1204 . 
     As briefly mentioned herein, eartip  1203  can include a plurality of support structures  1214   a - c  constructed as springs that bridge between an inner surface  1204  of outer eartip body  1206  and inner eartip body  1208 , as shown in  FIG. 12C . Each support structure  1214   a - c  can include a linear spring that can apply a resistive force against compression to evenly spread pressure across a wide area. When configured as a linear spring, each opposing end of the spring can be attached to a respective base plate  1216  and  1218  that can provide a rigid platform to which the spring can attach to and also provide a surface for the support structure to attach to surfaces  1210  and  1204  of inner eartip body  1208  and outer eartip body  1206 , respectively. Although  FIG. 12C  illustrates coil springs, embodiments are not limited to such configurations and that any suitable mechanical feature capable of applying linear force in the same manner are envisioned herein, such as elastic posts. 
     Support structures discussed herein can be formed of any material suitable for resisting the total collapse of the outer eartip body. For instance, support structures can be formed of a nylon material that is rigid but has enough elasticity to compress a certain degree while resisting compressive force. Support structures can also be formed of silicone, which can be the same silicone material used to form the inner eartip body and outer eartip body. In some embodiments, support structures can be formed of the above-mentioned materials reinforced with filaments, such as fabric filaments and/or nylon filaments to achieve a targeted compression rate. 
     E. Dynamic Outer Eartip Bodies 
     As can be appreciated herein, the outer eartip body of an eartip according to some embodiments of the present disclosure can press against an inner surface of an ear canal to form an acoustic seal, according to some embodiments of the present disclosure. This acoustic seal can enhance the quality of sound experience by the user, but it can also sometimes be improperly fitted to the ear canal. Thus, in some embodiments, the eartip can include a dynamic outer eartip body that can alter its diameter/cross-sectional size to complement the diameter of the ear canal in which it is inserted. 
       FIGS. 13A-13B  are cross-sectional views of an exemplary eartip  1300  including a dynamic outer eartip body  1302  in a sliding rod configuration, according to some embodiments of the present disclosure. Dynamic outer eartip body  1302  can include a rod  1304  and a track  1306  along which rod  1304  can slide along the length of outer eartip body  1302  to alter its diameter. Track  1306  can be attached to inner diameter  1308  of outer eartip body  1302 , and rod  1304  can be attached to outer surface  1310  of inner eartip body  1312 . In some embodiments, rod  1304  can be attached to a hinge  1314  disposed on outer surface  1310  so that rod  1304  can slide along track  1306  while being in a fixed position on outer surface  1310 . When eartip  1300  is not inserted into an ear canal, dynamic outer eartip body  1302  can have a first diameter  1316 . However, when eartip  1300  is inserted into an ear canal, dynamic outer eartip body  1302  can alter its diameter to second diameter  1318  that is smaller than first diameter  1316  to fit and conform to the size of the ear canal. In some embodiments, rod  1304  can slide upward along track  1306  to allow dynamic outer eartip body  1302  to alter its diameter like an umbrella, as shown in  FIG. 13B . By being able to dynamically alter its diameter/cross-sectional size, dynamic outer eartip body  1302  can better fit into a variety of ear canals, thereby improving its comfort and acoustic seal across a wide range of ear canal sizes. In certain embodiments, several rods and tracks are implemented around a circumference of inner eartip body  1312  and positioned equally spaced apart from one another in a symmetrical arrangement when viewed top-down. 
     Although  FIGS. 13A and 13B  illustrate track  1306  being formed on outer eartip body  1302  and rod  1304  being attached to outer surface  1310 , embodiments are not limited to such a configuration. In some instances, track  1306  can be formed on outer surface  1310 , and rod  1304  can be attached to outer eartip body  1302  and configured to slide along track  1306 , e.g., slide along outer surface  1310 , to change the diameter of outer eartip body  1302 . As an example, a spiral track can be formed around outer surface  1310  of inner eartip body  1312 , and a single, circular track can be formed around inner surface  1308  of outer eartip body  1302 . One end of rod  1304  can be set in the spiral track while the other opposite end can be set in the circular track. In such instances, as rod  1304  rotates with respect to inner eartip body  1312  and outer eartip body  1302 , the angle of rod  1304  with respect to inner eartip body  1312  can change, thereby altering the diameter of eartip  1300 . This rotational movement can be effectuated by the user making a twisting/screwing motion on eartip  1300 . It is to be appreciated that any other suitable implementation is envisioned herein without departing from the spirit and scope of the present disclosure. 
     In some embodiments, the dynamic outer eartip body can be configured in a sliding plate configuration.  FIGS. 14A-14B  are top-down views of an exemplary eartip  1400  including a dynamic outer eartip body  1402  in a sliding plate configuration, according to some embodiments of the present disclosure. Dynamic outer eartip body  1402  can include a plurality of segments  1404   a - h  that can slide against and overlap portions of one another to alter its diameter/size. As more overlap between segments  1404   a - h  is achieved, the diameter of dynamic outer eartip body  1402  decreases. For instance, when eartip  1400  is not inserted into an ear canal, dynamic outer eartip body  1402  can have a first diameter  1406 . However, when eartip  1400  is inserted into an ear canal, as shown in  FIG. 14B , dynamic outer eartip body  1402  can alter its diameter to second diameter  1408  that is smaller than first diameter  1406  to fit and conform to the size of the ear canal. By being able to dynamically alter its diameter/cross-sectional size, dynamic outer eartip body  1402  can better fit into a variety of ear canals, thereby improving its comfort and acoustic seal across a wide range of ear canal sizes. 
     Although embodiments herein discuss eartips with an outer eartip body formed as a cantilevered structure that has one end freely suspended a distance away from the inner eartip body and defines a deflection zone, embodiments are not limited to such embodiments. Rather, some embodiments can have both ends of the outer eartip body extend from the inner eartip body to define a cavity within which materials can fill to form a pliable structure. 
       FIGS. 15A-15B  are cross-sectional views of an exemplary eartip  1500  having an outer eartip body  1502  that extends from two regions of an inner eartip body  1504  to define an enclosed pocket  1506 , according to some embodiments of the present disclosure. Outer eartip body  1502  can extend from a first region  1508  of inner eartip body  1504  at an interfacing end  1510  of the eartip body and from a second region  1512  of inner eartip body  1504  near an attachment end  1514  of the eartip body. Outer eartip body  1502  can extend between first region  1508  and second region  1512  and curve away from inner eartip body  1504  in a concave profile. The curvature of outer eartip body  1502  can define pocket  1506  within which vacant space can reside. The vacant space can provide a region within which one or more fillers can be contained. Any suitable filler that provides a soft, compliant structure for allowing outer eartip body  1502  to conform and contour to the inner surfaces of an ear canal can be used, such as a foam material that can change its volume without changing its mass, or any other material having a viscoelastic property that compresses quickly yet rebounds slowly. One of such materials can be an under-cured fluorosilicone material. That way, when eartip  1500  is inserted into an ear canal, outer eartip body  1502  can compress into pocket  1506  and the filler material can resist deformation of outer eartip body  1502  to provide a soft, comfortable feel as shown in  FIG. 15B . 
     Because outer eartip body  1502  extends from two regions of inner eartip body  1504  and does not have a cantilevered structure, outer eartip body  1502  may not need high structural rigidity. Instead, outer eartip body  1504  can be formed of a soft, highly compliant material, such as a thin silicone layer or a fabric. Outer eartip body  1504  may only need to operate as a membrane that holds the filler material in pocket  1506 . Although  FIGS. 15A-15B  illustrate eartip  1500  as having a pocket  1506  that can be vacant space or occupied with a filler material, embodiments are not so limited. In some additional embodiments, no pocket may exist. Instead, the outer eartip body can be molded with the inner eartip body and thus form a solid structure. 
     It is to be appreciated that while embodiments herein discuss eartips having eartip bodies molded onto attachment structures for coupling with a housing, embodiments herein do not require eartips to be formed with attachment structures. Instead, eartips having features discussed herein can be directly fused onto the housing without the use of an attachment structure. Thus, eartips can be formed of a soft, monolithic structure that is directly attached to the housing and not separable from the housing. The entire eartip can be formed of only one material that is soft and compliant, like silicone, or it can include a filler material as discussed herein. 
     It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled so as to minimize risks of unintentional or unauthorized access or use, and the nature of authorized use should be clearly indicated to users. 
     Although the invention has been described with respect to specific embodiments, it will be appreciated that the invention is intended to cover all modifications and equivalents within the scope of the following claims.

Metadata:
Filing Date: 20190926
Publication Date: 20210518
Grant Date: 20210518
Priority Date: 20190325
Inventors: HATFIELD, DUSTIN A.
AOYAGI, SHOTA
EMMOTT, TIMOTHY E.
HUWE, ETHAN L.
LERNER, MITCHELL R.
MCINTOSH, Sean T.
TSAI, Yi-Fang D.
DELLA ROSA, Jason C.
SHEPPARD, Patrick W.
PARKER, Samuel G.
FEATHERS, David J.
TWEHUES, BRIAN R.
STRONGWATER, Daniel
Assignee: APPLE INC
CPC Classifications: [{"code": "H04R2460/11", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R1/1058", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04R1/1016", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R1/023", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R2460/11", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R1/1016", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R1/1016", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R1/1016", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R2460/11", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 72605375