Personal audio unit and manufacturing method thereof

Abstract

A personal audio unit (PAU) is described. The PAU includes: a housing in which a cavity is formed; an electronics module located within the cavity; wherein the cavity includes a solidified encapsulant contacting at least a portion of the electronic module and an inner wall of the housing. A method of manufacturing a personal audio unit (PAU) is described. The method includes the steps of: forming a housing, the housing forming a cavity therein, the housing having a fill port into the cavity; positioning the electronic module within the cavity; introducing a liquid encapsulant into the cavity via the fill port such that the liquid encapsulant enters a gap between the electronic module and the inner surface of the housing, and; the liquid encapsulant is cured to form a solid encapsulant.

Description

Technical Field

[0001] The present invention relates to personal audio units and, in particular, but not exclusively, to a resilient personal audio unit and a method of manufacturing a resilient personal audio unit. Background Art

[0002] Personal audio units come in many forms. Most commonly, a personal audio unit provides sound directly to a user's ear(s), typically in the form of a unit that engages the ear or a pair of units that engage respective ears. Paired units can be physically connected to each other, for example, via a headband or neckband, or via an interconnecting cable. Paired units can be wirelessly interconnected, for example, via a Bluetooth connection.

[0003] The portable audio unit is connected directly to the ear or the user, either engaging with the ear or being held against the ear, or a combination of both. There is a risk that the portable audio unit may fall out of the user's ear(s). When this happens, there is a risk of damaging the housing of the portable audio unit or the various components located therein. Portable audio units are typically small. They can be easily misplaced. When misplaced, there is a risk that they may be damaged again unintentionally, for example by being stepped on.

[0004] It is particularly dangerous for a personal audio unit to become dislodged from the user's ear during physical activity, such as during exercise, such as while running or while working out at the gym, such as during "CrossFit" or powerlifting. Periods of physical activity may also naturally coincide with times when there is a risk of a displaced portable audio unit being damaged (e.g., stepped on) if dropped. It is important that personal audio units be shock and impact resistant. Typical environments in which physical activity occurs may also potentially damage personal audio units, such as hard floors, muddy areas, puddles, etc.

[0005] Furthermore, there is a need for personal audio units that are resistant to damage due to liquid ingress and / or dust or dirt ingress. For example, being waterproof, water-resistant, or sweat-resistant is an important characteristic. This is particularly true during physical activity, when sweating is possible, or when swimming or showering.

[0006] The present invention has been devised in view of the above considerations. Summary of the Invention

[0007] The present invention includes combinations of the described aspects and preferred features, unless such combinations are clearly not permitted or explicitly avoided. According to a first aspect, a personal audio unit PAU is provided. The PAU comprises: a housing forming a cavity within the housing; and an electronic module located within the cavity. Optionally, the cavity comprises a solidified encapsulant contacting at least a portion of the electronic module and the inner wall of the housing. In this way, a PAU is formed that is resistant to damage. The inventors have tested the PAU according to the present invention and found that it performed well in impact resistance tests and heavy object drop tests. In particular, the solidified encapsulant can improve the structural integrity of the housing. The solidified encapsulant can also improve resistance to damage from water / sweat and dirt / dust.

[0008] Optionally, the housing is a rigid housing or a substantially rigid housing. The housing is rigid enough to maintain its shape when there is no external force. In certain embodiments, the housing is formed of a plastic material, such as a nylon material.

[0009] Optionally, the electronic module comprises a power supply unit located within the cup, the cup being located within the cavity. In some embodiments, the power supply unit comprises a battery unit.

[0010] Optionally, the cup is substantially surrounded by the encapsulant.In some embodiments, the inside of the cup in which the power supply unit is located is substantially free of encapsulant.

[0011] Optionally, the cup is formed of a rigid material, such as plastic. In some other embodiments, the cup is formed of a resilient material, such as foam, such as closed-cell foam.

[0012] Optionally, the PAU includes a sound driver configured to provide sound to a user, wherein a sound-emitting portion of the sound driver is exposed from the encapsulant. In this manner, an encapsulant-free sound transmission path is provided. This can result in improved audio performance and shock absorption.

[0013] Optionally, the main body of the acoustic driver is housed or coated in a flexible or resilient material, such as latex or silicone. The flexible or resilient coating is positioned between the main body of the acoustic driver and the set encapsulant. The flexible or resilient coating provides some cushioning between the acoustic driver and the set encapsulant.

[0014] Optionally, the cavity is divided into an upper void and a lower void.

[0015] Optionally, encapsulant is located in the lower void and the upper void is substantially free of encapsulant.The upper void may provide a location for electronic components that may be damaged by the encapsulant or components that have performance characteristics that may be degraded by the presence of the encapsulant.

[0016] Optionally, the cavity is separated by a partition of the electronic module. In some embodiments, the partition of the electronic module is a circuit board. In this way, the number of components in the PAU can be reduced because the PCB acts as both the PCB (holding the electronic components) and the partition wall in the cavity.

[0017] Optionally, an upper surface of the partition facing the upper void comprises at least one user interface component. In some embodiments, the at least one user interface component comprises a switch for user control of the PAU.

[0018] Optionally, the at least one user interface component comprises a light for providing user feedback of operation of the PAU.

[0019] Optionally, the PAU comprises at least one power electrical contact for charging the power supply unit, the at least one electrical contact being electrically connected to the electronic module.

[0020] Therein, the PAU comprises at least one electrical data contact for transmitting data to and / or from the electronic module.

[0021] Optionally, the electronics module includes a memory module for storing data for playback by the PAU. In this way, the PAU can be used for audio playback without a (eg, wirelessly) connected data source (eg, a mobile phone).

[0022] Optionally, the upper void is at least partially defined by a flexible wall. The flexibility allows a user to deform the flexible wall to engage a switch within the PAU.

[0023] Optionally, the PAU includes at least one support structure within the cavity to engage the electronic module. This supports the electronic module within the cavity during the introduction of the encapsulant. In some embodiments, the PAU includes multiple such support structures. The electronic module may have engagement features to engage with specific support structures. This ensures proper alignment of the electronic module within the cavity.

[0024] Optionally, at least one support structure is an integrally formed part of the housing. In other words, at least one support structure can be formed from the same material as the housing. This can allow for simpler manufacturing.

[0025] Optionally, the encapsulant is a potting compound. In some embodiments, the potting compound is a two-part epoxy.

[0026] Optionally, the electronic module includes a wireless communication unit. In some embodiments, the wireless communication unit includes an antenna. In some embodiments, the antenna is exposed from the encapsulant, for example, the antenna can be located in the upper gap.

[0027] Optionally, the PAU is an earplug. Optionally, the PAU is a hearing aid. Optionally, the outer contour of the PAU is shaped to engage with the user's ear.

[0028] According to a second aspect, a personal audio system is provided. The system comprises a pair of PAUs, each PAU in the pair being according to the first aspect.

[0029] Optionally, the system includes a case configured to house the paired PAUs. In some embodiments, the case is a charging case configured to charge the PAU's power supply when the PAUs are engaged with the case. In some embodiments, the case is a carrying case configured to house the PAUs when not in use. In some embodiments, the case is a carrying case and a charging case.

[0030] Optionally, the box includes a box power supply unit configured to supply power to the power supply unit of each PAU.

[0031] Optionally, the outer contour of the first of the pair is shaped to engage with the user's left ear, and the outer contour of the second of the pair is shaped to engage with the user's right ear.

[0032] According to a third aspect, a method for manufacturing a personal audio unit (PAU) is provided. The method includes the following steps: forming a housing having a cavity formed therein, the housing having a fill port for accessing the cavity; positioning an electronic module within the cavity; introducing a liquid potting agent into the cavity via the fill port such that the liquid potting agent enters a gap between the electronic module and an inner surface of the housing; and curing the liquid potting agent to form a solid potting agent.

[0033] Optionally, the housing is a rigid housing or a substantially rigid housing. The housing is rigid enough to maintain its shape when there is no external force. In certain embodiments, the housing is formed of a plastic material, such as a nylon material.

[0034] Optionally, the method comprises the step of vibrating the housing during or after the introduction of the liquid potting agent.In this way, the intrusion of potting agent into the gap between the electronic module and the housing can be improved.

[0035] Optionally, the method comprises partitioning the cavity into an upper void and a lower void. Optionally, the partition is formed by a partitioning portion of the electronic module.

[0036] Optionally, introducing the liquid potting agent includes introducing the liquid potting agent into the lower void.

[0037] Optionally, the housing includes a vent aperture, the method including introducing the channel member through the vent aperture, a portion of the channel member being located within the cavity during introduction of the liquid potting agent and during curing of the liquid potting agent.

[0038] Optionally, the method includes withdrawing the channel member after the liquid potting agent has solidified, thereby forming a channel through the solidified potting agent.

[0039] Optionally, the electronic module comprises a power supply unit, and the passage is located between the vent opening and the power supply unit.

[0040] Optionally, forming the housing comprises connecting at least two housing components to each other, wherein the electronic module is located within a cavity formed thereby. In some embodiments, an adhesive is provided between a connection point of the at least two housing components.

[0041] Optionally, the method comprises attaching a nib to the PAU, for example to a filling port. Optionally, the nib is configured for attachment to an ear canal engagement unit.

[0042] Optionally, introducing the liquid potting agent includes introducing the liquid potting agent into the lower void via a fill port.

[0043] Optionally, the method includes engaging a plug with the fill port.

[0044] Optionally, the plug is contacted with a liquid encapsulant.

[0045] Optionally, the small head is configured for attachment to the ear canal engaging unit. Optionally, the small head is shaped for attachment to the ear canal engaging unit.

[0046] Features described in relation to the first or second aspect may be implemented in the third aspect. Features described in relation to the third aspect may be implemented in the first or second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Examples and experiments illustrating the principles of the present invention will now be discussed with reference to the accompanying drawings, in which:

[0048] Figure 1 An embodiment of a personal audio unit according to the present invention is shown;

[0049] Figure 2 shows an alternative view of an embodiment of a personal audio unit according to the present invention;

[0050] Figure 3 shows an alternative view of an embodiment of a personal audio unit according to the present invention;

[0051] Figure 4 shows a schematic overview of an embodiment of a personal audio unit system according to the present invention;

[0052] Figure 5 shows a cross-sectional view through an embodiment of a personal audio unit according to the present invention;

[0053] Figure 6shows a cross-sectional view through an embodiment of a personal audio unit according to the present invention;

[0054] Figure 7 shows a cross-sectional view through an alternative embodiment of a personal audio unit according to the present invention;

[0055] Figure 8 A plug according to the invention is shown;

[0056] Figure 9 shows a simplified cross-sectional view through an embodiment of a personal audio unit according to the present invention;

[0057] Figure 10 showing a view of a cap component of an embodiment of a personal audio unit according to the present invention;

[0058] Figure 11 shows a cross-sectional view through an electronics module of an embodiment of a personal audio unit according to the present invention;

[0059] Figure 12 An outline of a manufacturing method according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0060] Aspects and embodiments of the present invention will now be discussed with reference to the accompanying drawings. Further aspects and embodiments will be apparent to those skilled in the art. All documents mentioned herein are incorporated herein by reference.

[0061] Figure 1 An earbud 1 is shown. The earbud 1 is an example of a personal audio unit according to the present invention. Other examples include earphones, headphones, headsets (e.g., "Bluetooth headsets"), radio units (e.g., military radios (or the earpiece portion thereof)), and hearing aids.

[0062] The earbud 1 is formed by an outer shell 2. The outer shell 2 includes an upper shell portion 3 and a lower shell portion 4. The upper shell portion 3 and the lower shell portion 4 are formed from a substantially rigid material. In an example, the material of the shell 2 is a rigid plastic material, such as a rigid nylon material. In some embodiments, the material of the shell 2 is polyamide-12. In some other embodiments, the shell can be formed from flexible nylon. The shell is rigid enough to maintain its shape in the absence of external forces. The upper shell portion 3 and the lower shell portion 4 are physically joined to each other along a shell interface 5. In an embodiment, the upper shell portion 3 and the lower shell portion 4 can be connected to each other using an adhesive (not shown). The shell 2 of the earbud 1 is shaped to fit snugly in the outer ear region of the user's ear between the antihelix and the antitragus. It should be understood that some embodiments may not be shaped in this way. Some embodiments are shaped to have a portion that hangs around the outside of the user's ear. In some embodiments, the PAU is held against the user's ear, for example via a headband attached to the personal audio unit.

[0063] The earplug 1 includes a small head 6. The small head 6 is located on the side of the earplug 1 for engaging with the user's ear. The small head 6 is used to connect to the end of the earplug ( Figure 1 ). The earbud tip is formed of a flexible material for comfortably engaging the outer portion of the user's ear canal. The engagement of the earbud tip with the user's ear canal can provide acoustic isolation from external sounds. The earbud tip can be a user-replaceable component. In addition, the user can select an earbud tip that fits the size of their ear canal. This allows the earbud to be comfortably but securely connected to the ear canal. The tip 6 can be formed of a different material than the shell 2. The material of the tip 6 can be flexible. In some embodiments, the material of the tip 6 is more flexible than the material of the shell 2. In some embodiments, the tip has a Shore hardness of 88A. In some embodiments, the tip 6 is a separate, replaceable component from the shell 2. In some embodiments, the tip 6 is a separate component that engages with the shell 2 during manufacturing, but the tip 6 is not user-removable or replaceable. In Figure 1 In some embodiments, the small head 6 is a separate component that is physically engaged with the lower housing portion 4. To engage with the housing, the small head 6 includes barbs that engage with the edge of the housing 2 to hold the small head 6 in place. In some embodiments, the small head 6 is formed of TPU (thermoplastic polyurethane). In other embodiments, the small head 6 is integrally formed with a portion of the housing 2.

[0064] The earbud 1 also includes a cap 7. The cap 7 covers the aperture formed in the upper housing portion 3. The cap 7 is formed from a flexible material, for example, a material that is more flexible than the material of the housing 2. In some embodiments, the cap 7 is formed from TPE (soft flexible filament). The cap is flexible to allow the cap 7 material to move slightly when pressed by the user. In some embodiments, the cap 7 has a Shore durometer of 88A.

[0065] In some embodiments, the cap 7 is integrally formed with the housing or upper housing portion. In such embodiments, the flexibility of the cap's material may be sufficient to allow the user interactions described below with respect to the (separate) cap 7. In such embodiments, the material forming the cap / housing / housing portion may be thinner in the cap region to increase the cap's flexibility in the cap region.

[0066] As will be discussed later, cap 7 allows the user to interact with the electronics located within earbud 1, such as to control certain operations of earbud 1. Cap 7 is located on the side of earbud 1 that is exposed when earbud 1 is engaged with the user's ear. In some embodiments, small head 6 and cap 7 are located on opposite sides of earbud 1. In some embodiments, small head 6 and cap 7 are located on opposite sides of housing 2. In some embodiments, small head 6 is located within a first housing portion (e.g., lower housing portion 4), and cap 7 is located within a second housing portion (e.g., upper housing portion 3). In some embodiments, cap 7 is formed of a rigid material.

[0067] Figure 2 An alternative view of the earplug 1 is shown. The earplug tip 8 is shown connected to the small head 6, which is Figure 2 The earbud tip 8 includes a sound channel 9 that allows sound to be transmitted from the audio unit ( Figure 2 7 . The earplug 1 includes three microphone holes 10 located in the cap 7 . Three microphone holes 10 are illustrated, but those skilled in the art will readily appreciate that other embodiments may have more or fewer microphone holes, including a single microphone hole 10 . The microphone holes 10 each include a microphone breathable membrane spanning the microphone hole 10 . Each breathable membrane substantially prevents liquid and / or dirt / dust from passing from the outside of the earplug 1 through the microphone breathable membrane into the cavity inside the housing 2 . The microphone hole 10 and the microphone breathable membrane allow external sound to be transmitted to a microphone (not shown) located inside the earplug 1 . In some embodiments, a single membrane is provided to cover multiple microphone holes. This external sound can be used, for example, for making phone calls, voice control, or for noise cancellation purposes. In some embodiments, the earplug 1 does not have a microphone and does not have (one or more) microphone holes 10 . In some embodiments, the earplug 1 has a microphone but does not have any (one or more) microphone holes 10 . In such an embodiment, sound can reach the microphone via transmission through the cap 7 and / or the housing 2 . In some embodiments, the earplug 1 includes more than one microphone, for example, four microphones.

[0068] The breathable membrane can be a waterproof breathable membrane. Suitable breathable membranes are available from GORE.2. In some embodiments, the breathable membrane can have a thickness between 0.1 and 1.0 mm, for example 0.25 mm.

[0069] Figure 3An alternative view of earbud 1 is shown. A microphone hole 10 is visible, located within cap 7. Microphone hole 10 is located in the peripheral area of ​​cap 7, adjacent to the edge of the opening in upper housing portion 3. Microphone hole 10 can be located in cap 7 so that it is as close as possible to the user's mouth when earbud 1 is in use. This can improve the sound quality of the user's voice detected by the microphone unit in earbud 1 and reduce external noise interference.

[0070] Figure 4 The earbuds 1 are schematically illustrated in the context of a personal audio system 11. The system 11 includes a pair of earbuds 1, a charging / carrying case 12, and a wirelessly connected computing device 13. Where the earbuds 1 are provided as a pair of earbuds 1, the earbuds 1 can be shaped as a right earbud 1 and a left earbud 1, one of each. The right earbud 1 can be shaped as a mirror image of the left earbud 1, such that the left earbud 1 is configured to fit snugly with the user's left ear and the right earbud 1 is configured to fit snugly with the user's right ear. In other embodiments, the two earbuds 1 can be shaped substantially identically. In some embodiments, the earbuds 1 are labeled "left" and "right" (or "L" and "R"). The paired earbuds 1 can be configured to communicate wirelessly with each other.

[0071] The wirelessly connected computing device 13 is configured to wirelessly connect to one or both earbuds 1. The wireless connection can be used to transfer data from the computing device 13 to the earbuds 1 and vice versa. For example, the computing device 13 can transmit substantially real-time sound data to one or more earbuds 1, which are then played back by one or both earbuds 1. In some embodiments, one or both earbuds 1 transmits the sound data from a microphone unit in the earbuds 1 to the computing device 13. In some embodiments, the computing device 13 transmits its sound data to one or both earbuds 1, which then stores the sound data on one or both earbuds 1 for later playback (e.g., when a wireless connection with the computing device 13 is unavailable). To this end, in some embodiments, the earbuds 1 include memory for data storage (e.g., RAM, such as 4 gigabytes of RAM). In some embodiments, the memory is configured to store audio data (e.g., music or podcast content). In some embodiments, the wireless connection is a Bluetooth connection or a Wi-Fi connection. In some embodiments, the computing device 13 is a mobile phone, a smartwatch, a computer, a tablet, a "phablet," a music / video player, or any other suitably configured device. In some embodiments, the earbuds 1 are both wirelessly connectable (e.g., via Bluetooth) and include memory for data storage. In this way, the earbuds 1 are more flexible in their use cases, depending on the availability of a suitable computing device 13.

[0072] When not in use, the earbuds 1 can be stored in a charging / carrying case 12. The charging / carrying case 12 includes a case power supply unit 14. When the earbuds 1 are located within the housing 13, an electrical connection 15 is established between the earbuds 1 and the case power supply unit 14. The case power supply unit 14 thereby charges a power supply unit (not shown) within each earbud 1.

[0073] Each earbud 1 may include a magnet (not shown). The magnet is configured to engage with a corresponding magnet or ferrite material in the charging / carrying case 12. The magnetic interaction between the earbud 1 and the case 12 holds the earbud 1 in place in the device and serves to provide precise alignment of the earbud's charging contacts with the case power supply unit 14.

[0074] Figure 5 A cross section through the earplug 1 is shown. Figure 1 、 Figure 2 and Figure 3 The externally visible components in Figure 5 are marked similarly in .

[0075] Figure 5 In particular, the interface of the lower housing portion 4 with the small head 6 is illustrated. During manufacture, the small head 6 is pushed into a port 20 formed in the lower housing portion 4. The earplug tip 8 engages with the exposed distal end 21 of the small head 6.

[0076] The small head 6 includes a sound channel 22 formed therethrough. The channel allows the transmission of sound from the sound driver 23. The small head 6 includes a breathable membrane 24. The breathable membrane 24 substantially prevents liquid, dust and dirt from entering the cavity inside the shell 3, 4 through the breathable membrane 24 from the outside of the earplug 1. The breathable membrane can be a waterproof and breathable membrane. Suitable breathable membranes are available from GORE and other suppliers. In some embodiments, the breathable membrane can have a thickness between 0.1 and 1.0 mm, for example, a thickness of 0.25 mm. The breathable membrane 24 can be coated with an adhesive on at least one surface to help waterproof the breathable membrane 24 to the small head and / or the shell. The breathable membrane 24 can also or alternatively be captured and held in place between the small head and the shell engaged with the small head. The sound generated at the sound driver 23 passes through the breathable membrane 24 along the sound channel 22 and exits the orifice 9. At this point, the sound is transmitted to the user's ear canal, which is engaged with the earplug end 8.

[0077] The port 20 in the lower housing portion 4 forms an entrance into the inner cavity 25 of the earbud 1. The inner cavity 25 of the earbud 1 houses a plurality of electronic components, which are examples of electronic modules. These components may include any of the following: a sound driver, a power supply unit (e.g., a battery), a microcontroller, a wireless connection module, a switch for user input to the earbud 1, a user feedback unit (e.g., a light or a series of lights). The electronic components inside the cavity 25 do not completely fill the cavity 25 formed by the housings 3 and 4; some empty space remains. The switch(es) may constitute a multi-function button that allows control of the software running on the earbud 1 (e.g., skipping songs, pausing, activating a specific operating mode).

[0078] During manufacture, a liquid potting agent is introduced into the cavity 25. The liquid potting agent is introduced via a port 20 in the housing, which forms a fill port. The liquid potting agent substantially fills the space between the components located within the cavity 25. In other embodiments, a separate liquid introduction port may be included, for example at an interface or joint between the housing components 3, 4. The liquid introduction port forms the fill port. In such an embodiment, after the liquid potting agent has been introduced, a plug may be inserted into an orifice formed at the joint between the housing parts. The plug may be inserted before the potting agent solidifies. The plug may include a protrusion extending into the liquid potting agent. The liquid potting agent solidifies around the protrusion, holding the plug in place. In some embodiments, the protrusion is a hoop extending into the liquid potting agent. For example, see Figure 7 and Figure 8 .

[0079] The inventors have discovered that, regardless of the liquid introduction orifice (via the small-head orifice or another orifice), it is advantageous for the inner surface of the housing facing the orifice to be generally inclined and not flat during liquid introduction. This approach has been found to reduce air pockets and bubbles trapped in the solidified encapsulant. This reduction in air pockets and bubbles increases the strength of the finished PAU. Specifically, the first surface contacted by the initial portion of the liquid encapsulant is inclined relative to being flat. This allows the liquid to naturally flow to low points, gradually filling and covering the underlying surface. This promotes complete filling of the cavity.

[0080] Figure 6 The fill level 26 of the encapsulant entering the earplug 1 via the port 20 is shown. Note that Figure 5 compared to, Figure 6 The orientation of the earplug 1 in the ear is reversed. The fill level 26 of the liquid encapsulant leaves the sound output portion of the sound driver 23 free of liquid encapsulant. The liquid encapsulant is injected between the gap between the output portion of the sound driver 23 and the opening of the port 20. During the introduction of the encapsulant, the opening of the sound driver 23 may be temporarily blocked to prevent the liquid encapsulant from being inadvertently introduced into the sound driver 23.

[0081] After being introduced into cavity 25, the liquid encapsulant hardens into a solid encapsulant during a curing step. The hardened encapsulant conforms tightly to the components inside the earplug, protecting them from damage, such as from vibration and shock. The hardened encapsulant also increases the structural integrity of shells 3 and 4. As a result, earplug 1 is strengthened and has improved resistance to catastrophic failure, such as from crushing forces. The encapsulant also increases the earplug 1's resistance to water, sweat, and dust / stains.

[0082] In some embodiments, the body of the sound driver can be encased or coated in a flexible or resilient material, such as latex or silicone. Once the encapsulant hardens around the coated sound driver body, the flexible or resilient material can provide cushioning to the sound driver 23, allowing for slight movement between the sound driver 23 and the earbud 1. This can improve acoustic performance.

[0083] In some embodiments, the housings 3, 4 include pressure equalization orifices. The pressure equalization orifices allow the pressure inside the housings to equalize during the introduction of the liquid encapsulant. This can help ensure that the liquid encapsulant invades all expected voids / gaps in the cavity.

[0084] In some embodiments, the encapsulant is a potting compound, such as a low-viscosity potting compound. In some embodiments, the encapsulant in its liquid form is a molten polyamide compound. In some embodiments, the encapsulant is a two-part epoxy resin. In some embodiments, once cured, the encapsulant has a Shore hardness of 84D. In some embodiments, the encapsulant can be an electric grade 832 series epoxy resin. In some embodiments, the combination of the two parts of the epoxy resin can result in an exothermic reaction. As a result, the temperature of the liquid encapsulant can be slightly increased. This, in turn, can reduce the viscosity of the liquid encapsulant. This, in turn, can improve the fill factor of the liquid encapsulant, making it easier to fill all available space in cavity 25. In some embodiments, the temperature of the liquid encapsulant is less than approximately 50 degrees Celsius, for example, approximately 35 degrees Celsius. In this way, thermal damage to electronic components (e.g., a power supply unit) can be avoided.

[0085] Figure 7 An alternative embodiment of the PAU 1 is shown. In this embodiment, the liquid potting agent is introduced into the cavity 25 via an orifice 25A formed at the joining line between the housing parts 3, 4. In such an embodiment, after the liquid potting agent is introduced, a plug 25B is inserted into the orifice 25A. After the potting agent is introduced into the cavity 25 and before the potting agent solidifies, the plug (see Figure 8) engages with orifice 25A. Plug 25B includes a protrusion 25C that extends into the liquid potting compound. The liquid potting compound solidifies around protrusion 25C, holding plug 25B in place. In some embodiments, protrusion 25C is a collar that extends into the liquid potting compound. The protrusion of plug 25B extends below the fill level 26 of the liquid potting compound. Plug 25B may include labels indicating the "left" and "right" (or "L" and "R") of the respective PAU 1 with which plug 25B engages.

[0086] Figure 7 Also shown is a lower inner surface 25D of the cavity 25. The lower inner surface 25D of the cavity 25 is the inner surface of the cavity 25 opposite the opening through which the liquid encapsulant is introduced. Figure 7 In the embodiment of FIG, this is orifice 25A. Lower inner surface 25D is generally inclined and is not oriented flat. This inclination can be achieved by orienting PAU 1 during the introduction of the liquid encapsulant and / or by the shape of the inner surface. In this way, it has been found that air pockets / bubbles trapped in the solidified encapsulant can be reduced. The reduction of air pockets / bubbles increases the strength of the finished PAU. In particular, the first surface (lower inner surface 25D) that the initial portion of the liquid encapsulant contacts is inclined relative to being flat. This allows the liquid encapsulant to flow to the low points on the lower inner surface and gradually fill and cover the lower inner surface 25D. The cavity is then subsequently filled with liquid encapsulant. The inclined lower inner surface 25D can facilitate complete filling of cavity 25 with liquid encapsulant.

[0087] Figure 7 An alternative location for the breathable membrane 24 is also shown. The breathable membrane 24 substantially prevents liquids and dust and dirt from entering the cavity inside the shell 3, 4 from the outside of the earplug 1 through the breathable membrane 24. The breathable membrane can be a waterproof breathable membrane. Suitable breathable membranes are available from GORE and other suppliers. In some embodiments, the breathable membrane can have a thickness between 0.1 and 1.0 mm, for example, 0.25 mm. The breathable membrane 24 can be coated in an adhesive to aid in waterproof attachment to the tip and / or shell. Figure 7 In the embodiment of the present invention, the breathable membrane 24 is held and maintained in place between the small head 6 and the shell engaged with the small head 6. This retention and maintenance can also contribute to a watertight joint.

[0088] Figure 7Also illustrated is a portion of the housing that engages the driver 23, including a driver engagement socket 23A that is sized and shaped to engage at least one sound transmitting portion of the driver 23. The driver engagement socket 23A can be sized to accommodate a driver 23 coated in a resilient material (e.g., latex or silicone). The driver 23 can be engaged with the driver engagement socket 23A prior to the introduction of the liquid potting agent. This can protect the sound transmitting portion of the driver 23 from contact with the liquid potting agent. Return to Figure 5 In some embodiments, battery 27 is located within cup 28. Cup 28 can be sealed to the PCB of the electronic components around the peripheral edge, thereby forming a battery cavity inside cup 28. As a result, battery 27 is separated from the encapsulant. Cup 28 is made of a rigid plastic material. In some other embodiments, cup 28 can be formed of foam, such as closed-cell foam. In some embodiments, cup 28 closely conforms to the shape of battery 27. In some other embodiments, cup 28 has a peripheral wall that is shaped to allow a flat landing area to be formed on the PCB to which cup 28 is attached. For example, the shape of the peripheral edge of cup 28 can be set to allow a flat landing area to be formed on the PCB to which cup 28 is attached, wherein the landing area is substantially free of electronic components. In some embodiments, this means that the peripheral wall of cup 28 has a non-circular shape.

[0089] In some other embodiments, the cup 28 is omitted. In such embodiments (e.g., Figure 7 In an embodiment (e.g., a resilient material layer 28A may be positioned adjacent to the battery 27 to allow for some battery expansion in the event of a battery failure. The resilient material 28A may also or alternatively be capable of absorbing battery venting / gases in the event of a battery failure. The resilient material layer 28A may be a closed-cell foam. The resilient material layer may be positioned between the battery and an adjacent PCB.

[0090] Figure 9 The figure shows a simplified diagram of earbud 1, with most of the internal electronics module omitted for explanatory purposes. Within cavity 25, two voids are formed: a lower void 29 and an upper void 30. Lower void 29 and upper void 30 are separated by an interface printed circuit board (PCB) 31. Interface PCB 31 is part of the electronics module. In other embodiments, different components or dedicated wall members may be used to separate cavity 25.

[0091] The interface PCB 31 is mounted within the cavity 25 so as to abut against a peripheral shoulder 32 formed on the inner surface of the upper housing portion 3. The connection between the shoulder 32 and the PCB 31 substantially prevents liquid encapsulant from entering the upper void 30 from the fill port 20. In some embodiments, the lower void 30 and the upper void 29 are substantially airtightly sealed from each other by the interface PCB 31. The surface of the shoulder 32 includes a channel 33 (e.g., a scalloped channel) formed therein. The channel 33 can form a continuous ring around the shoulder 32. During manufacturing, a sealant can be introduced into the channel 33. The sealant can help form an airtight seal between the PCB 31 and the shoulder 32. The sealant can be silicone. In some embodiments, an adhesive can be used instead of the sealant. In some other embodiments, a combination of an adhesive and a sealant can be used.

[0092] Cap 7 may define a portion of upper void 30. The surface of interface PCB 31 facing upper void 30 includes electronic components with which a user directly interacts. These components may include, but are not limited to, any of the following: one or more switches, one or more lights, at least the voice-responsive portion of a microphone unit, and at least a portion of a wireless communication antenna. In some embodiments, the upper surface of interface PCB 31 includes a contact dome switch. Because upper void 30 is not filled with liquid potting agent, these components are not exposed to the liquid potting agent, which could otherwise impair their functionality.

[0093] Figure 10 The cap 7 is shown. The inner surface of the cap 7 includes an interface protrusion 40. When the cap 7 is connected to the earbud 1, the interface protrusion 40 protrudes into the upper void 30. The interface protrusion 40 is sized and shaped to engage with a switch located in the upper void 30. This can reduce the travel required for the cap 7 before the switch is activated by the user pressing the cap 7. In embodiments where the cap is integral with the housing, the cap can still include the interface protrusion 40. The material at the housing / cap can be flexible enough (at least in the area of ​​the cap) to allow the travel required to activate the switch.

[0094] Cap 7 also includes a microphone isolation wall 41. Microphone isolation wall 41 divides upper void 30 into two sections: a microphone section and a light section. The microphone section includes at least the sound-responsive portion of the microphone. The light section may include one or more lights. The microphone isolation wall may prevent light from the light(s) from escaping from microphone hole(s) 10. Microphone isolation wall 41 may engage the upper surface of the interface PCB.

[0095] Return to Figure 9 ,although Figure 9 Not shown, the lower void 29 contains other electronic components of the earbud 1 and the circuit board(s) and power supply unit.

[0096] In some embodiments, earbud 1 includes at least one support structure within cavity 25. In some embodiments, the support structure in lower void 29 engages the electronics module, supporting the electronics module in place at least while liquid potting agent is introduced into cavity 25. In some embodiments, the support structure is an integrally formed portion of housing 3, 4. A liquid passageway between the support structure and the electronics module can be formed to allow liquid potting agent to pass around the electronics module during manufacturing.

[0097] Figure 11 An electronic module 50 according to an embodiment is shown. The electronic module 50 is formed of three flexible interconnected printed circuit boards (PCBs): an interface PCB 31, a main PCB 51, and a charging PCB 52. In other embodiments, the electronic module 50 of the earbud 1 may take a different form, such as more or fewer PCBs. In some embodiments, the electronic module 50 may form a single PCB. The thickness of the PCB substrate may be between 0.2 and 1.5 mm, for example 1 mm. Components mounted to the PCB substrate may increase the thickness of the electronic module. The PCB substrate may be a fiberglass epoxy laminate or "FR4". In some embodiments, the PCB substrate may be a multi-layer substrate, such as a 2-layer, 4-layer, 6-layer, or 8-layer PCB substrate. In other embodiments, the PCB substrate may have an odd number of layers. Multi-layer substrates (e.g., an 8-layer PCB substrate) may be particularly susceptible to damage from flexing or vibration. Therefore, it may be particularly advantageous to protect such PCBs with the encapsulant of the present invention.

[0098] The battery 27 is electrically connected to the main PCB 51. The battery 27 is an example of a power supply unit. As described above, in some embodiments, the battery is located within the cup 28 (see Figure 5 ). The battery 27 is electrically connected to the charging contacts 34 on the charging PCB 52. When the electronic module is installed in the housing 2, the electrical contacts are exposed via a pair of apertures in the lower housing portion 4. The charging PCB 52 also includes a pair of data contacts (not shown). When the electronic module is installed in the housing 2, the data contacts are also exposed via a pair of apertures in the lower housing portion 4. Two data contacts and two electrical contacts can be arranged at the four corners of a square on the lower housing portion 4. In some embodiments, the electrical contacts can have dual functionality - both for charging and for data transmission. A method 60 of manufacturing an earbud 1 according to an embodiment of the present invention will now be described. Although reference is made to the earbud 1 of the aforementioned figures, the method is applicable to the manufacture of various personal audio devices.

[0099] like Figure 10As shown in FIG, method 60 includes a housing forming step 62. During the housing forming step 62, the upper housing portion 3 and the lower housing portion 4 are formed. The housing forming 62 may include molding the housing portions 3, 4. The housing portions 3, 4 may be formed from a rigid molded plastic material.

[0100] Method 60 also includes an electronic module forming step 64. In electronic module forming step 64, the electronic components to be housed within the housing are connected to each other to form the electronic module. The electronic module is described with respect to the previous figures. As needed, electronic module forming step 64 may include electronically and electrically connecting the various components to each other. Forming the electronic module as a single unit for housing within housings 3 and 4 improves the manufacturability of the earbud 1.

[0101] Method 60 also includes a housing closing step 66. The housing closing step includes connecting upper housing portion 3 and lower housing portion 4. An adhesive is applied to the mutual connection point of upper housing portion 3 and lower housing portion 4 before connecting upper housing portion 3 and lower housing portion 4. Upper housing portion 3 and lower housing portion 4 are connected to each other, wherein the electronic module is located within cavity 25 formed by upper housing portion 3 and lower housing portion 4.

[0102] Method 60 also includes a cap attachment step 68. In this step, flexible cap 7 is attached to the aperture formed in upper housing portion 3. An adhesive is applied to the interconnection point between upper housing portion 3 and cap 7 prior to attachment. In some embodiments, cap attachment step 68 is performed after encapsulant introduction step 72 and curing step 74.

[0103] In some embodiments, the cap is integrally formed with the housing, for example integrally formed with the upper housing portion 3. Thus, the cap is formed during the housing forming step 62 and the detailed cap attaching step 68 is omitted.

[0104] Method 60 includes a vent channel forming step 70. In this step, a pin is introduced through the vent opening of the housing. The pin remains in place during the encapsulant introduction step 72 and the curing step 74 (see below). After curing step 74, the pin is withdrawn. Thus, a vent channel is formed between the battery 27 and the environment. In embodiments where the battery 27 is located within the cup 28, the vent channel can extend inside the cup 28. More specifically, the cup 28 can include a cup boss, and the housing can include a housing boss, with the cup boss and the housing boss engaging each other. The vent channel can pass through the interconnection between the cup boss and the housing boss. Typically, the vent channel forms a path for venting gases generated during a battery failure. The vent channel passes through the solidified encapsulant. This improves the safety of the earplug 1. In some embodiments, the portion of the vent channel that passes through the housing (or housing portion) is aligned with the direction in which the housing (or housing portion) is removed from the mold used to form the housing (or housing portion) during the housing forming step 62. This can facilitate manufacturing. The vent channel can include a vent channel breathable membrane. The vent channel breathable membrane substantially prevents liquid from entering the cavity inside the housings 3 and 4 through the vent channel from outside the earplug 1. The breathable membrane can be a waterproof breathable membrane. Suitable breathable membranes are available from GORE.2. In some embodiments, the breathable membrane can have a thickness between 0.1 and 1.0 mm, for example, 0.25 mm.

[0105] In some other embodiments, the vent channel and the vent channel forming step 70 are omitted.

[0106] Method 60 also includes a potting agent introduction step 72. In potting agent introduction step 72, potting agent liquid is introduced into the void within cavity 25 formed by housings 3, 4. The liquid potting agent may contact at least a portion of the electronic module and at least the inner surface of the lower housing portion.

[0107] The liquid encapsulant may be introduced into the cavity under pressure. This may help ensure that the liquid encapsulant intrudes into all intended voids within the cavity in and around the electronic module.

[0108] Between 3 grams and 30 grams of liquid encapsulant may be introduced into a single PAU, for example, between 5 grams and 20 grams of liquid encapsulant, for example, between 8 grams and 15 grams of liquid encapsulant, for example, approximately 10 grams of liquid encapsulant.

[0109] During the introduction of the liquid encapsulant into the cavity, the earplug 1 may be vibrated in a vibration step. This can help ensure that the liquid encapsulant invades all intended voids in the cavity. This can also mitigate the presence of bubbles or air pockets within the liquid encapsulant. The vibration step may occur during or after the encapsulant introduction step 62.

[0110] In some embodiments, a liquid encapsulant is introduced into the cavity via the port 20. The liquid encapsulant may be introduced between the acoustic driver and the edge of the port 20. The fill level of the liquid encapsulant is such that the acoustic output portion of the acoustic driver 23 is free of the liquid encapsulant. The liquid encapsulant may be injected into the gap between the output portion of the acoustic driver 23 and the opening of the port 20. During the introduction of the encapsulant, the opening of the acoustic driver 23 may be temporarily blocked to prevent the liquid encapsulant from being inadvertently introduced into the acoustic driver 23.

[0111] In other embodiments, the liquid encapsulant may be introduced into the cavity via different apertures in the housings 3, 4. In particular, the liquid encapsulant may be introduced into the cavity via an aperture formed at the joining line between the housing parts 3, 4. For example, see Figure 7 In such an embodiment, after the liquid potting agent has been introduced, a plug may be inserted into the aperture formed at the junction between the housing parts. For example, see Figure 8 The plug may be inserted before the potting agent solidifies. The plug may include a protrusion that extends into the liquid potting agent. During the curing step, the liquid potting agent solidifies around the protrusion, holding the plug in place. In some embodiments, the protrusion is a hoop that extends into the liquid potting agent.

[0112] In some embodiments, the housings 3, 4 include pressure equalization orifices. The pressure equalization orifices allow the pressure inside the housings to equalize during the introduction of the liquid encapsulant. This can help ensure that the liquid encapsulant invades all intended voids in the cavity. The pressure equalization orifices can be closed after the encapsulant introduction step 72.

[0113] Method 60 also includes a curing step 74. During curing step 74, the liquid encapsulant within the housing cavity hardens into a solid state. Curing step 74 can include holding the earplug 1 substantially stationary for at least a predetermined curing time. The predetermined curing time can be between 30 minutes and 24 hours. The liquid encapsulant can have a set time of approximately 60 minutes.

[0114] Method 50 also includes a closing step 76. Closing step 76 includes closing port 20 through which the encapsulant was introduced into the cavity. In embodiments where the encapsulant was introduced via port 20, closing step 76 may include attaching the small head 6 to port 20. Closing step 76 may occur before, during, or after curing step 74.

[0115] The features disclosed in the preceding description, or in the following claims, or in the accompanying drawings, expressed in their specific form or as means for performing the disclosed functions, or as methods or processes for obtaining the disclosed results, may, where appropriate, be used alone or in any combination of these features to implement the invention in its different forms.

[0116] Although the present invention has been described in conjunction with the above exemplary embodiments, many equivalent modifications and variations will be apparent to those skilled in the art upon giving this disclosure. Therefore, the exemplary embodiments of the present invention set forth above are intended to be illustrative rather than restrictive. Various changes may be made to the described embodiments without departing from the spirit and scope of the present invention.

[0117] For the avoidance of any doubt, any theoretical explanations provided herein are intended to improve the reader's understanding. The inventors do not wish to be bound by any of these theoretical explanations.

[0118] Any section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described.

[0119] Throughout this specification, including the claims that follow, unless the context requires otherwise, the words “comprise” and “include” and variations such as “comprises”, “comprising”, and “including”, will be understood to imply the inclusion of stated integers or steps or groups of integers or steps but not the exclusion of any other integers or steps or groups of integers or steps.

[0120] It must be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from "about" one particular value and / or to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, when a value is expressed as an approximation by use of the antecedent "about," it should be understood that the particular value forms another embodiment. The term "about" with respect to a numerical value is optional and means, for example, + / - 10%.

Claims

1. A personal audio unit (PAU), comprising: a housing, forming a cavity within the housing; an electronics module located within the cavity; The cavity includes a solidified potting agent contacting at least a portion of the electronic module and an inner wall of the housing.

2. The personal audio unit of claim 1, wherein The electronics module includes a power supply unit located within a cup located within the cavity.

3. The personal audio unit of claim 2, wherein the cup is substantially surrounded by the encapsulant.

4. A personal audio unit according to any one of the preceding claims, wherein the personal audio unit comprises a sound driver configured to provide sound to a user, wherein a sound emitting portion of the sound driver is exposed from the encapsulant.

5. A personal audio unit according to any preceding claim, wherein the cavity is divided into an upper void and a lower void.

6. The personal audio unit of claim 5, wherein the encapsulant is located in the lower void and the upper void is substantially free of encapsulant.

7. A personal audio unit according to claim 5 or 6, wherein The cavity is divided by a partition portion of the electronic module.

8. The personal audio unit of claim 7, wherein: An upper surface of the divider portion facing the upper void includes at least one user interface component.

9. A personal audio unit according to any one of claims 5 to 8, wherein The upper void is at least partially defined by a flexible wall.

10. A personal audio unit according to any preceding claim, wherein The electronic module includes a wireless communication unit.

11. A personal audio unit according to any preceding claim, wherein The personal audio unit is an earbud.

12. A personal audio unit according to any preceding claim, wherein the personal audio unit is a hearing aid.

13. A personal audio system comprising a pair of personal audio units, each personal audio unit of the pair being according to any preceding claim.

14. The personal audio system of claim 13, further comprising a housing configured to house the pair of personal audio units.

15. A method of manufacturing a personal audio unit (PAU), comprising the steps of: forming a housing defining a cavity therein, the housing having a fill port into the cavity; positioning an electronics module within the cavity; introducing liquid potting agent into the cavity via the fill port such that the liquid potting agent enters a gap between the electronic module and an inner surface of the housing, and; The liquid encapsulant is cured to form a solid encapsulant.

16. The method of claim 15, further comprising the step of vibrating the housing during or after introducing the liquid encapsulant.

17. A method according to claim 15 or 16, comprising dividing the cavity into an upper void and a lower void using a partition portion of the electronics module.

18. The method of any one of claims 15 to 17, wherein introducing the liquid potting agent comprises introducing the liquid potting agent into the lower void via the fill port.

19. A method according to any one of claims 15 to 18, wherein the method comprises engaging a plug with the fill port.

20. The method of claim 19, wherein the plug is in contact with the liquid encapsulant.

21. A method according to any one of claims 15 to 20, comprising attaching a small head to the personal audio unit.

22. The method according to claim 21, wherein The small head is configured for attachment to the ear canal engaging unit.

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