HK1173263B - Inhibiting moisture intrusion in a very small form factor consumer electronic product - Google Patents

Description

Inhibiting moisture intrusion in very small form factor consumer electronics products

Technical Field

The disclosed embodiments relate generally to consumer electronics, and more particularly, to a highly portable, extremely small media playback device.

Background

In recent years, small form factor consumer electronics such as media players and cellular telephones have become smaller, lighter, and yet more powerful by incorporating more powerful working components into smaller, more compact packaging structures. This reduction in size and increase in density may be due in part to the ability of manufacturers to prepare various working components (such as processors and memory) in smaller sizes while increasing the power and/or operating speed of the working components. However, this trend toward smaller size, greater component density, and greater power can create many continuing design and assembly challenges.

For example, small form factor consumer electronics (such as media players) may require many components to fit into a housing that is extremely small in volume. Assembling the various components into such a small size housing may require complex, expensive, and time consuming assembly techniques. In addition, aesthetic factors can severely limit the arrangement, size, and number of components used to manufacture small form factor consumer electronic products. For example, proper alignment of external features such as buttons is extremely difficult to achieve when the small size of the consumer electronic device itself can severely reduce the available tolerance stack-up of the assembled components.

Another challenge to be addressed involves appropriate techniques for mounting structures within small form factor consumer electronics products. For example, various internal component structures may be attached to the housing using fasteners such as screws, bolts, rivets, etc., and assembled in a sandwich-like manner in layers using conventional assembly techniques. However, using this technique for small form factor devices is time consuming, costly, and prone to error.

In view of the above, there is a need for improved techniques for inhibiting the flow of moisture in consumer electronic products, at least as a result of increasing component density and decreasing size.

Disclosure of Invention

A very small form factor consumer electronic product comprising at least: a one-piece housing having integral front and side walls that cooperate with the front opening to form a cavity, edges of the side walls defining a rear opening, wherein at least some of the edges have a flange, wherein at least one of the side walls includes an opening sized to receive an I/O device. Further comprising a clip assembly having a size and shape conforming to the rear opening, the clip assembly having a plurality of attachment features for securing the clip assembly to the one-piece housing; and a plurality of moisture barriers, each of the plurality of moisture barriers being formed of a water resistant material, wherein the plurality of moisture barriers cooperate to inhibit moisture from moving from an external environment into the cavity. In the described embodiment, at least one of the plurality of moisture barriers is an audio jack fitting electrical contact moisture barrier. The audio jack fitting electrically contacting the moisture barrier includes at least: an electrical contact comprising a flat pad portion and a central protrusion portion, the electrical contact being integrally formed with the audio jack fitting housing. Further comprising a sealing tape layer applied to the housing of the audio jack fitting, combined with the pad portion of the electrical contact part and exposing the protrusion portion; and a flexible substrate layer, wherein the flexible substrate layer is electrically connected with the electrical contact by means of the protruding portion through a solder reflow process. The solder reflow process causes liquid solder to enter and fill recessed areas between the raised portions, sealing band, and the flexible substrate layer, the solder-filled recessed areas providing a moisture intrusion barrier between the external environment and the interior portions of the very small form factor consumer electronic product.

In another embodiment, a method is described. The method includes at least the following operations. Providing an audio jack assembly, the audio jack assembly comprising: an audio jack cartridge having a size and shape conforming to an audio terminal connected to an external circuit; a plurality of electrical contacts integrally formed with the audio jack barrel, the electrical contacts formed by a flat pad portion and a protrusion portion. The method includes at least applying a layer of sealing tape to the electrical contacts such that the sealing tape forms a layer over the pad portions and exposes the protruding portions; applying a flexible substrate on the sealing tape layer; and electrically connecting the flexible substrate to the electrical contacts by means of the protruding portions, wherein the electrical connection is made by performing a solder reflow operation on the audio jack assembly such that solder paste associated with the flexible substrate liquefies and flows into recessed portions between the protruding portions of the electrical contacts and the sealing strip, wherein the solidified solder forms a water-resistant seal that substantially prevents water from flowing out of the audio jack barrel.

A moisture inhibiting sealing structure for use in an electrical assembly of an electrical system is described that prevents moisture from flowing from a water-resistant portion of the electrical assembly to a non-water-resistant portion of the electrical system. The moisture-suppressing seal structure includes at least: a primary seal structure for providing a first seal layer; and a trim seal structure applied to the primary seal structure. The trim seal structure cooperates with the primary seal structure to prevent moisture from flowing between the water-resistant portion of the electrical assembly and the non-water-resistant portion of the electrical system.

In one aspect, the trim seal structure is formed during a solder reflow operation.

Other aspects and advantages will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.

Drawings

The embodiments will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which:

fig. 1 is a front view of an exemplary minimal form factor media player in accordance with an illustrative embodiment.

Fig. 2 shows a side view of the example minimal form factor media player of fig. 1 with the clip in a closed state.

Fig. 3 shows a side view of the example minimal form factor media player of fig. 1 with the clip in an open state.

Fig. 4 is an exploded view showing various sub-assemblies used to prepare the components of the media player 10.

Fig. 5-7 show various perspective views of a representative housing in accordance with the illustrated embodiments.

Fig. 8-11 show various components of a click wheel assembly in accordance with the illustrated embodiments.

Fig. 12 shows a representative clip assembly in accordance with the illustrated embodiment.

Fig. 13 illustrates a representative click fitting seal, in accordance with an embodiment.

Fig. 14 illustrates a Main Logic Board (MLB) assembly, in accordance with an embodiment.

Fig. 15-17 show perspective views of an audio jack according to the illustrated embodiment.

18-19 show an internal moisture detection system in accordance with the illustrated embodiments.

Fig. 20 shows an assembly tool for surface mounting an audio jack fitting to a plate-like printed circuit board, in accordance with the illustrated embodiment.

21-24 illustrate various aspects of a retention button assembly in accordance with the illustrated embodiments.

FIG. 25 illustrates a technique for reducing tolerance stack-up of a playlist button relative to a housing, according to an embodiment of the invention.

FIG. 26 shows a flow chart detailing an assembly process in accordance with the illustrated embodiment.

FIG. 27 shows a flow chart detailing the process of shunting electrostatic charge to chassis ground in accordance with the illustrated embodiment.

FIG. 28 shows a representative media player in accordance with the illustrated embodiments.

Fig. 29-32 illustrate techniques and structures for moisture ingress seals well suited for forming audio jack fittings in accordance with the illustrated embodiments.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the principles underlying the illustrated embodiments. It will be apparent, however, to one skilled in the art, that the illustrated embodiments may be practiced without some or all of these specific details. In other instances, well known process steps have not been described in detail in order to avoid unnecessarily obscuring the underlying principles.

Aesthetic portable computing devices, and in particular techniques for inhibiting moisture intrusion into a portable computing device, are discussed herein. The portable computing device may have a size and weight that makes the portable computing device easy to carry. For the remainder of this discussion, without loss of generality, the portable computing device will be discussed with a minimal form factor media player arranged to store a plurality of digital media items, any of which may be selected and decoded for play. However, due to their small size and light weight, any decoded media item signals (such as audio) are not broadcast using an audio transducer such as a speaker. The media player may use an interface, such as an audio jack, to pass the decoded signal to external circuitry for further processing rather than broadcasting the audio signal as sound. For example, when the decoded media file is an audio file, the decoded audio signal may be transmitted to external circuitry included in or attached to a headset, external speakers, audio recorder, or the like, using an audio jack.

The minimal form factor media player may be sized to be easily held in the hand, transported in a pocket, or attached to a lanyard and hung from the neck, wrist, waist, etc. Very small form factor media players may have limited functionality due in part to the small size and lack of available space. Due to limited functionality, it is desirable to have a very small form factor media player that can be used to perform certain tasks, such as storing, retrieving and decoding a limited number of digital files. Since the additional processing of decoding digital files can be done outside of a very small form factor media player, the input features for controlling the operation of the media player can be limited to media file selection, media file decoding, and simple operational parameters such as volume up/down. Thus, the number and variety of input features may also be limited. For example, selection of one (or more) stored media items may be made by a user manipulating a mechanical input along a row of mechanical buttons (such as dome switches). The mechanical input may also be used to modify other functions performed by the media player, such as increasing/decreasing volume, fast forwarding/rewinding, and so forth. In some cases, it may be advantageous to provide specific input features arranged to perform specific functions. For example, an input feature in the form of a slide switch may be used to enable a hold function or a pause function, whereas a simple feature such as a button may be used to perform a complex operation, such as selecting a playlist (group of related media items).

A minimal form factor media player may include an outwardly seamless one-piece housing formed from a number of durable materials. In one particular embodiment, the housing may be formed of a conductive material suitable for providing good chassis grounding. Thus, the housing may be formed from materials such as metal, conductive plastic, or conductive composites. One of the advantages of using metal for the housing is the ability of the metal to provide good electrical grounding for any internal components that require a good ground plane. A good ground plane may be used to help mitigate deleterious effects caused by, for example, electromagnetic interference (EMI) and/or electrostatic discharge (ESD). In one particularly useful construction, the housing may be constructed from a single metal blank, such as an aluminum blank. The one-piece housing may be shaped and sized to accommodate multiple internal components from a single aluminum billet. Furthermore, due to the unitary construction, openings in the housing for receiving various switches, connectors, and the like can be formed without the need for adding additional structural supports. By surface treating the aluminum, the aesthetic appearance and feel of the media player can be significantly enhanced, as well as durable corrosion and scratch resistance. For example, anodizing aluminum enclosures can form a layer on the aluminum surface that enhances the luster and shine of the aluminum enclosure while increasing corrosion and mar resistance.

Simple and effective design and assembly techniques that promote the aesthetics and functionality of extremely small form factor media players can be used. For example, because the working components within the media player are small in size and in close proximity, any external moisture that enters the interior of the media player significantly increases the likelihood of damage through corrosion or short circuits. Minimizing or at least inhibiting the ingress of moisture into the interior of the media player can be an important factor in enabling long-term operation of the media player. Thus, as part of the overall design, multiple moisture/contaminant barriers may be strategically placed within the media player. The barrier may take a variety of forms such as a waterproof tape, an adhesive, a thermoformed plastic cover, and the like. For example, the barrier may comprise a waterproof film such as Kapton, Mylar, etc. The barrier may also take the form of a block of compressible, waterproof material such as silicone rubber. In the illustrated embodiment, a block-shaped moisture barrier may have a portion removed, thereby forming a cutout sized to receive a robotic arm for activating a mechanical input, such as a switch. In the illustrated embodiment, the robotic arm may pass through a cut formed in a waterproof material that effectively isolates portions of the robotic arm that are in contact with the active circuitry, and exterior portions that are exposed to the external environment. In this way, the strategic placement of the moisture barrier can significantly reduce the risk of moisture entering the interior of the media player, resulting in corrosion and short circuits.

In addition to providing good moisture barriers, in some embodiments, portions of selected moisture barriers may be reinforced in a manner that enables the formation of electrically conductive pathways. For example, with the silicone rubber moisture barrier discussed above, the inherent insulating properties of the silicone rubber can be modified by the application of selected dopants (e.g., small silver spheres) so that the silicone rubber can become somewhat conductive to the extent that a good ground path can be formed. In this way, not only is the moisture barrier significantly blocking moisture from entering the interior of the media player, but ESD protection is made easier by providing a mechanism to disperse the accumulated charge to the ground plane in the form of a housing.

These and other embodiments are discussed below with reference to fig. 1-28. However, those skilled in the art will readily appreciate that the detailed description given below with respect to these figures is for explanatory purposes only and should not be construed as limiting the invention.

Referring first to fig. 1-3, fig. 1-3 illustrate, in different perspective views, a representative minimal form factor media player 10 (hereinafter referred to simply as media player 10). The media player 10 may process data, and more specifically media data such as audio, video, images, and the like. For example, the media player 10 may generally correspond to a device that functions as a music player. The media player 10 may have working components enclosed and supported by a housing 12. The media player 10 may have an upper portion 14, side portions 16 and a bottom portion 18. The media player 10 may include one or more input devices. The one or more input devices may include touch sensitive input devices, one of which may take the form of a point-touch wheel assembly mounted to the front of the housing 12, as shown in FIG. 1. The click wheel assembly may include at least a click wheel 20. The click wheel 20 may be formed of an elastic material such as plastic or metal. The click wheel 20 may have a raised annular portion 22 on which a plurality of icons 24 are present, each icon corresponding to a particular button function that the media player 10 is capable of performing in response to a user touch event. The button functions may include selecting and playing a song, fast forwarding or rewinding a song, increasing/decreasing volume, and so forth. In the illustrated embodiment, the individual button functions may be implemented by means of mechanical click actions.

To convert a user touch event into a signal that can be processed and acted upon by the media player 10, each icon 24 can be associated with a sensor arrangement (described below). When pressure is applied to a particular icon, the relevant portion of the clicker wheel 20 may respond by mechanically engaging the corresponding sensor of the plurality of sensors. In the simplest case, an electrical signal is generated each time the sensor is engaged. In most cases, the signal is monitored by an electronic interface that converts the signal into information. Which can then be used by the media player 10 to perform desired control functions. The click wheel 20 may also include a center button 26. The center button 26 may be formed of plastic or metal. When pressure is applied to the center button 26, a signal can be generated that causes the media player 10 to perform a predetermined function. For example, when pressure is applied to the center button 26, a signal may be generated and forwarded to the processing circuitry that enables the media player 10 to start or stop the playing of the media item. It should be noted that the shape of the click wheel 20 can also be varied greatly. For example, the click wheel 20 may be circular, rectangular, square, oval, triangular, and the like.

The bottom portion 18 may include a clip assembly 28 having a closed configuration as shown in fig. 2 and an open configuration as shown in fig. 3. The clip assembly 28 can be used to secure the media player 10 to an external feature such as a garment, lanyard, or the like. The clip assembly 28 may include a clip 30 integrally formed with a torsion spring block 32, the torsion spring block 32 including a torsion spring, the torsion spring block 32 being attached to a clip plate 34 (also referred to as a door plate 34). The clip plate 34 can include various hook and latch attachment features that can be used to attach the clip assembly 28 to the housing 12 and completely enclose the internal components of the media player 10. To securely attach the media player 10 to an object using the clip assembly 28, pressure P may be applied to the clip 30 near the torsion spring block 32 to pivot the clip 30 away from the clip plate 34 to transition the clip assembly 28 from the closed configuration of fig. 2 to the open configuration of fig. 3. In this manner, a gap 36 of sufficient size to accommodate an object or a portion of an object (e.g., a sleeve, a lapel, a lanyard, etc.) may be formed between the clip plate 34 and the clip 30. Then, by removing the pressure P applied to the clip 30, the clip 30 can be engaged with the object by the elastic force generated by the torsion spring in the torsion spring block 32 when the clip fitting 28 is restored to the closed state. In this manner, the clip 30 can grip and secure an object without damaging the object or the media player 10, thereby easily securing the media player 10 to an object such as clothing, a lanyard, or the like.

The media player 10 may also include one or more switches, such as a play switch, a hold switch, and the like, accessible through respective openings in the housing 12. For example, the hold switch button 38 may be used to activate or deactivate the click wheel 20. This is typically done to avoid unnecessary commands generated by the click wheel 20, such as when the media player 10 is stored in a user's pocket. The hold switch button 38 may take a variety of forms, such as a two-position button, a three-position button, or more. For example, when configured as a three-position switch as shown in fig. 2 and 3, the hold switch button 38 may have a first position, a second position, and a third position relative to the housing 12. To provide a quick and unambiguous indication to the user of the position of the hold switch button 38, a label 40 may be provided. The label 40 may provide distinctive visual indicia (such as differently colored portions in the form of green portions GP and blue portions BP as shown in fig. 2 and 3) to indicate the position of the hold switch button 38. For example, in position 2 (corresponding to the central position of the hold switch button 38), the label 40 can unambiguously indicate that the hold switch button 38 has been placed in position 2 by simultaneously presenting the green portion GP and the blue portion BP of the label 40. To remain clear and distinct over the expected operating life of the media player 10, the label 40 may be formed from a resilient material such as metal.

The media player 10 may include an audio jack port 42. The audio jack port 42 can mechanically and electrically couple the media player 10 to external circuitry so that audio information can be output from the media player 10 and data can be input to the media player 10. In some cases, power may also be delivered to the media player 10 by way of circuitry associated with the audio jack port 42. The audio jack port 42 can receive terminals (not shown) that can facilitate the transfer of information (or power) between the media player 10 and external circuitry. For example, audio signals from the decoded digital audio file may be transmitted to an external audio rendering device, such as headphones, speakers, or the like. To minimize the number and complexity of mechanical input assemblies required to operate the media player 10, multiple multi-function mechanical inputs may be provided. For example, the playlist button 44 may be used to enable complex functionality, such as selecting a playlist of media items for playback by the media player 10. As is well known in the art, a playlist is a collection of media items, such as songs, played one at a time as a group of choices. Thus, any song identified as belonging to a particular playlist can be selected, decoded and played simply by pressing the playlist button 44. In this way, the need for complex user interaction (such as scrolling) can be eliminated, making the media player 10 simple in design and easy to operate.

Fig. 4 is an exploded view showing various sub-assemblies used to prepare the components of the media player 10. The sub-assembly may include a housing 100, a click wheel assembly 200; a clip assembly 300, a Main Logic Board (MLB) assembly 400, and a hold switch assembly 500.

A first perspective view of an embodiment of housing 12 is shown in fig. 5. housing 100 may be formed from a variety of materials, such as plastic or metal, which may be forged, molded or otherwise machined to a desired shape. In those instances where the media player 10 has a metal housing and incorporates RF-based functionality, it may be advantageous to provide at least a portion of the housing 100 in the form of a radio (or RF) transparent material (e.g., ceramic, plastic). In any event, the housing 100 can be configured to at least partially enclose any suitable number of internal components associated with the media player 10. The housing 100 may enclose and support various structural and electrical components (including integrated circuit chips and other circuitry) internally to provide computing operations to the media player 10. The integrated circuit may take the form of a chip, chipset, module, any of which may be surface mounted to a printed circuit board (or PCB) or other support structure.

Thus, the enclosure 100 is essentially a housing or "exoskeleton" of the overall device containing the various device components, and can also serve as a starting point for assembling the overall device. The housing 100 may also include various openings, some of which may be used to mount inserts including various internal components, as well as buttons, ports, audio jacks, and the like, as described below. For example, the front opening 102 may be sized to receive the click wheel assembly 200, while the rear opening 104 may receive the clip assembly 300. The opening 106 (shown more clearly in fig. 6 and 7, with fig. 6 and 7 providing second and third perspective views of the housing 100, respectively) may be sized to receive the audio jack port 42, while the opening 108 may receive the playlist button 44, and the opening 110 may receive the hold switch button 38. The securing features 112 may be used to help secure the internal components to the housing 12 using fasteners such as screws. The flange 114 can support a waterproof seal arranged to at least inhibit moisture ingress into the interior of the media player 10.

When the housing 100 is formed of a good conductor (such as aluminum), the housing 100 can function as a chassis ground that provides a good ground plane for the internal electrical components. In addition to providing a good ground plane for internal electrical components, the metallic nature of the housing 100 can help prevent electrostatic charge buildup, thereby reducing the likelihood that electrostatic discharge will damage sensitive electrical components. However, to improve the aesthetic appearance of the housing 100, a substantially non-conductive surface layer may be formed on the housing 100. The surface layer can provide excellent corrosion and scratch resistance, but can prevent good electrical contact with the underlying metal. For example, in the case where the case 100 is formed of aluminum, the anodizing process can form one layer on the surfaces (inner and outer surfaces) of the case 100. This layer can interfere with good electrical contact with the underlying base aluminum, thereby severely reducing the ability of the housing 100 to provide chassis grounding. By selectively removing at least a portion 116 of the protective layer from the inner surface 118 of the housing 100, as shown in fig. 7, good electrical contact with the underlying aluminum base layer can be achieved.

Fig. 8-11 illustrate components of the click wheel assembly 200 and the relationship between the various components. It should be noted that the click wheel assembly 200 is an autonomous assembly, and once fully assembled, the click wheel assembly 200 is fully functional, enabling functional testing prior to incorporation into the media player 10. Referring first to fig. 8, the click wheel assembly 200 may include a ring-shaped button assembly 202. The annular button assembly 202 may include a click wheel 20 (described above) and a diaphragm 204, with the diaphragm 204 being attachable to an interior portion of the click wheel 20 with an adhesive. As shown in more detail in fig. 9, the diaphragm 204 may be formed from an elastomeric material such as silicone rubber. The diaphragm 204 may be sized to fully accommodate the click wheel 20. For example, the click wheel 20 may be positioned entirely above the diaphragm 204 within the diaphragm 204 in such a manner that when the upper surface 210 of the diaphragm 204 is attached to the click wheel 20 using, for example, an adhesive, the raised perimeter portion 206 of the diaphragm 204 can engage the outer edge 208 of the click wheel 20, thereby forming a tight seal between the click wheel 20 and the diaphragm 204. In this way, the ring button assembly 202 may be considered a single sealing subassembly. A spacer 212 may be placed within the recess 214 associated with the center button 26 of the click wheel 20 and each icon 24 in the annular region 22 prior to attaching the diaphragm 204 to the click wheel 20. The pads 212 may be used to adjust the mechanical response of the click wheel 20 to a touch event by a user. The pad 212 can adjust the distance the click wheel 20 moves in response to a touch event of a particular one of the icons 24 or the center button 26. In this way, the subjective feeling of the click wheel 20 can be modified as needed.

Fig. 10 shows a representative button plate 218 in accordance with the illustrated embodiment. The surface 216 of the diaphragm 204 may be used to secure the ring-shaped button assembly 202 to the button plate 218. The button plate 218 may be formed from a strong, resilient material such as metal or any suitable composite material. In the embodiment illustrated herein, however, the button plate 218 will be considered to be formed of metal without loss of generality. Thus, the metal button plate 218 may be formed of metal such as stainless steel and aluminum. The metal button plate 218 may be attached to the ring button assembly 202 by attaching the surface 216 of the diaphragm 204 to the surface 220 of the metal button plate 218 using any suitable adhesive, such as double-sided tape. A surface 220 of the metal button plate 218 may include a sensor 222 associated with a corresponding one of the icons 24 and 26. As described above, when pressure is applied to the click wheel 20 in the vicinity of an icon 24 or 26, the corresponding sensor 222 is able to respond to the applied pressure by generating a signal that can be used by the control circuitry to alter the operation of the media player 10.

In the illustrated embodiment, the sensor 222 may take the form of a mechanical switch, such as a dome button 222 (also referred to as a contact switch). The number of arrangements of the dome buttons 222 can be changed greatly. For example, the anti-rotation ring 224 may be arranged in such a way that the anti-rotation trolley 20 rotates around the dome button 222 associated with the central button 26. In the particular embodiment shown, the dome buttons 222 form an array of five switches connected to the clicker wheel flexible portion 226, each switch aligned with an associated one of the icons 24 and 26 on the clicker wheel 20. The clicker wheel flex section 226 may include a connector flex section 228, and the connector flex section 228 may be used to electrically connect the clicker wheel assembly 200 to the operating circuitry within the media player 10. In particular, the connector flex 228 may be coupled to the main logic board (or MLB) using a Zero Insertion Force (ZIF) coupling as described and illustrated below.

The metal button plate 218 may include a metal boss 230 welded to a downward facing surface 234. The metal boss 230 may be used to attach the metal button plate 218 (along with the click wheel assembly 200) to an internal component such as a printed circuit board (or PCB). The lugs 232 may be used to secure the click wheel assembly 200 to the clip assembly 300 during an assembly operation. For example, the clip assembly 300 may be latched to the metal button plate 218 using the lugs 232. As such, the metal button plate 218 may be considered to have a dual purpose, wherein the surface 220 of the metal button plate 218 may be used to support the ring button assembly 202, while the surface 234 shown in fig. 11 may be used to support components such as a printed circuit board via the soldered metal bosses 230, and the clip assembly 300 via the lugs 232. The connector 236 may be used to electrically connect the flexible connector 228 with an electrical component, such as an MLB. In addition, the opening 238 is aligned with the opening 112 formed in the housing 100. In this manner, the metal button plate 234 can be directly secured to at least the housing 100 with fasteners.

Fig. 12 illustrates an embodiment of a clip assembly 300. The clip assembly 300 may be pre-assembled and tested prior to use to complete assembly of the media player 10. The clip assembly 300 may be preassembled with fasteners 302. The fasteners 302 may take the form of screws 302. The screw 302 may be used to mount the clamping plate 34 to the torsion spring block 32 which houses the torsion spring 304. In the closed position, the torsion spring 304 may cause the clip 30 to compress the clip plate 34. The clip assembly 300 can be attached to the metal button plate 218 using a hook feature 306 that engages a lug 232 on the metal button plate 218. The attachment feature 308 may take the form of a hook that is capable of engaging an opening 240 formed in the metal button plate 218.

As shown in fig. 13, the sealing member 310 may be formed of a waterproof material such as silicon rubber. The seal 310 may be shaped to conform to the opening 106 of the housing 100 near the flange 114 formed about the opening 106. Near the flange 306, a seal 310 may be placed on the housing 100. In this manner, the seal 310 can prevent moisture or other liquids from entering the interior of the enclosure 100 from the external environment. This is particularly important because of the various openings within the housing 100 that each create a potential moisture ingress path.

The seal 310 may be sized and shaped according to the housing 100, and in particular the opening 106. The seal 310 may be shaped to inhibit moisture intrusion into the interior of the housing 100, particularly into those portions of the housing 100 having openings for input devices (such as buttons or switches) exposed to the external environment. For example, the opening in the seal 310 may correspond to a battery for powering the media player 10. On the other hand, the opening 314 may correspond to a Main Logic Board (MLB) juxtaposed with the battery. Since the MLB includes many electrical components that may not be water resistant, the portion 314 may be configured to provide a more reliable waterproof barrier than the portion 312.

The seal 310 may be placed directly on the flange 114 of the housing 100 during assembly of the media player 10. Once in place, the clip assembly 300 can be placed directly onto the seal 310 and pressure applied to the clip assembly 300. Pressure applied to the clip fitting 310 can cause the hooks 306 to engage the lugs 224 and attachment features 308 of the metal button plate 218, thereby engaging the openings 240. In this way, the click wheel assembly 200 and the clip assembly 300 can be securely attached to each other in a manner that minimizes moisture intrusion into the interior of the media player 10. By the above-described requirement of mounting the clip assembly 300 to the housing 100 using fasteners such as screws, there are no visible fasteners, thereby providing a clean, effective appearance to the media player 10.

The effects of moisture intrusion into the media player 10 can have serious consequences due to the small size and compactness of the media player 10. For example, due in part to the high packing density of the internal components within the media player 10, even small amounts of moisture can form leakage paths between components, resulting in reduced or even compromised functionality. This is particularly true when there is little unused space within the media player 10 and thus a higher likelihood of moisture-induced damage results. In addition to the possibility of damage due to moisture ingress, damage from electrostatic discharge (or ESD) is also severe. Also, due to the small size and compact geometry, the electric field strength may become so high that considerable voltage peaks may occur. This is particularly true when considering the close proximity of sensitive components in the MLB and external switches such as the playlist button 44 and hold button 38. A user merely touching a switch, or even merely picking up the media player 10, is likely to cause electrostatic discharge that may cause electrical damage to many sensitive electrical components. Thus, ESD protection and prevention of moisture/contaminant ingress are important considerations in the design and layout of the media player 10.

Fig. 14 illustrates a Main Logic Board (MLB) assembly 400, in accordance with an embodiment. The MLB assembly 400 may include a MLB 402. The MLB 402 may include a Printed Circuit Board (PCB)404 on which a plurality of integrated circuits 406 are mounted and electrically connected. The integrated circuit may include at least one microprocessor, semiconductor (e.g., flash) memory, various support circuits, and the like. A battery 408 connected to the PCB404 may provide power to the integrated circuit via an electrical connector 410. Battery 408 may be a lithium ion battery. Also shown are a playlist contact switch 412 and a "side activation" hold contact switch 414. It should be noted that the term "side-activated" is intended to convey the idea that the hold switch 38 may be offset from the position of the hold contact switch 414 due in part to layout considerations and component density. In this way, an armature (armature) (described in more detail below) may connect the hold switch 38 and the hold contact switch 414. The connector 416 is capable of connecting with the flexible connector 228 at the contacts 236. In one embodiment, the connector 416 may be a Zero Insertion Force (ZIF) connector as is well known in the art. Openings 418 may be aligned with welded metal bosses 230 and sized to receive fasteners, such as screws, that may be used to secure MLB assembly 400 to click wheel assembly 200. In this way, the fastener can securely connect the MLB fitting 400 and the click wheel fitting 200.

The MLB 402 may include an audio jack assembly 420, and the audio jack assembly 420 may be surface mounted to the PCB404 via an audio jack body 422. The audio jack fitting 420 may include an audio jack barrel 424 integrally formed with an audio jack body 422, with the audio jack body 422 each sized and placed on the PCB404 to align with the opening 106 in the housing 100. In this way, the audio jack barrel 424 is able to receive an audio jack terminal via the audio jack port 42, the audio jack terminal having electrical contacts that align with and electrically connect exposed portions of the audio jack contacts 426, as illustrated and shown in more detail in fig. 15 and 16. More specifically, fig. 15 shows a side view of audio jack assembly 420 showing the relative position of audio jack contacts 426 with respect to audio jack cylinder 424, audio jack body 422, and PCB 404. In the illustrated embodiment, the audio jack contact 426 may include a portion 427 embedded within the audio jack body 422. However, to achieve good electrical contact with the corresponding electrical contact on the audio jack terminal plugged into the audio jack port 42, a portion of the audio jack contact 426 may be in the form of an audio jack pad 430 exposed to the internal cavity 428 of the audio jack barrel 424.

It should be noted that the lumen 428 may be directly exposed to the external environment containing a significant amount of contaminants and moisture. Accordingly, care must be taken to account for any pathways between the interior cavity 428 and the interior of the media player 10 that may allow contaminants and moisture to pass through. Accordingly, the channels 432 may be considered potential flow channels between the contact terminals 434 and the internal cavity 428 disposed through the PCB openings 436 for connecting the audio jack pads 430 and the circuitry 438 surface mounted to the PCB 404.

To prevent, or at least minimize, the possibility of contaminants and moisture from invading the lumen 428, a moisture barrier may be used to severely restrict (if not completely block) any direct flow of contaminants and/or moisture along the passage 432. The moisture barrier may comprise more than one component. For example, to limit or eliminate the possibility of moisture or contaminants passing along the channel 432 to the interior of the media player 10, a plurality of moisture flow barriers may be included in the channel 432. In one embodiment, during surface mounting, the PCB openings 436 may be filled with solder used to electrically connect the connection terminals 434 with electrical traces on the PCB 404. As part of a standard assembly process, the PCB404 may undergo a wave soldering process, causing solder to flow over the surface of the PCB 404. The flow of solder can fill the PCB opening 436 by capillary action. The capillary action has the effect of sealing any gaps that may exist at the interface of the PCB404 and the connection terminal 434 and that may exist between the audio jack body 422 and the connection terminal 434.

Other moisture barriers that may be included in the channels 432 may include at least a laminate 440 instead of or in addition to solder. The layer 440 may be formed of a material well suited to blocking the flow of moisture or contaminants. For example, the laminate 440 may take the form of a film or tape (such as Kapton and Mylar) that can conform to the contours of the audio jack barrel 424 and the audio jack body 422. For example, the moisture flow barrier film 440 may be brought into direct contact with the audio jack body 422 and the audio jack barrel 424, extending to an area covering the contact retention area 442 shown in more detail in fig. 16. In some cases, an adhesive material may be required to ensure that the membrane 440 substantially conforms to the shape of the audio jack barrel 424 and the audio jack body 422. For example, an adhesive layer may be provided on the film 440, forcing the film 440 to conform to the surface features of the audio jack barrel 424 and the audio jack body 422. Providing an adhesive on the film 440 can be particularly beneficial when the film 440 is thin and may wrinkle. Any gaps between the membrane 440 and the audio jack body 422 and audio jack barrel 424 can themselves form additional pathways for moisture/contaminants to ingress into the interior of the media player 10. To ensure a perfect fit and to maximize the resistance to moisture and contaminants from flowing into the interior of the media player 10, the contact terminals 434 may pass through the membrane 440, thereby further preventing the flow of moisture/contaminants between the interior cavity 428 and the interior of the media player 10.

In another embodiment, the moisture flow barrier may take the form of a structure, such as a cover 444, which may be mounted directly to the audio jack fitting 420, as shown in fig. 17. The cover 444 may be formed from a water resistant material that may be formed using a thermoforming process to have a shape that conforms to the audio jack fitting 420. In particular, the cover 444 may include openings sized and positioned to receive the contact terminals 434 and mounting posts 446 for attaching the audio jack fitting 420 and the PCB 404. In some cases, it may be advantageous to secure cover 444 to audio jack fitting 420 with an adhesive. The lid 444 may be placed and secured during assembly. Because the cover 444 has been shaped to conform to the contours of the audio jack fitting 420, the possibility of gaps between the cover 444 and the audio jack body 422 and audio jack barrel 424 is virtually eliminated. Thus, in the case of using the cover 444, any crease-resistance measures required when using the film 440 are not required.

To monitor whether the interior of the media player 10 is exposed to moisture, a plurality of moisture indicators may be disposed within the interior of the media player 10. One of the most commonly used moisture indicators typically provides a visual indication by changing color (e.g., from white to red) when moisture comes into contact therewith. The visual indication may be viewed by viewing a port structure. In this way, any moisture ingress can be easily identified. Due to the direct exposure of audio jack interior 428 to the external environment, there is a possibility that moisture within audio jack interior 428 may ingress into the interior of media player 10 through other moisture ingress channels, even if not through channel 432. Thus, determining the path of any moisture inside the media player 10 from the outside environment can provide important data for design purposes as well as customer service and contact. Any abuse behavior will invalidate any manufacturer quality assurance. For example, if there is an indication of moisture penetration into the interior of the media player 10, then it is reasonable to conclude that the media player 10 has been exposed to an environment with a high concentration of moisture, such as a lake, a pool, or a stream of water. Thus, the warranty conditions are violated, and there is a possibility that there is a repair cost out of service.

A moisture detection system may be provided to determine whether moisture has intruded into the interior of the media player 10. It should be noted, however, that moisture is expected to be present in the audio jack interior 428. Thus, the moisture detection system described herein must distinguish between moisture that is expected to be present within audio jack interior 428 and moisture that has penetrated into the interior of media player 10.

FIG. 18 shows a moisture detection system 450 in accordance with the illustrated embodiment. The moisture detection system 450 may be located inside the media player 10. When moisture contacts the moisture detection layer, typically by changing color (e.g., from white to red), the moisture detection system 450 can provide a visual indication that moisture has penetrated into the interior of the media player 10. The moisture detection system 450 may be connected to a viewing port 452 at an end 454 of the audio jack cartridge 422 by an adhesive layer (not shown). The adhesive layer may be any suitable adhesive material, such as a double-sided pressure sensitive adhesive film (double-sided tape), an adhesive without a backing film, and the like. The moisture detection system 450 may include a frame 456 connected to the viewing port structure 452.

The moisture detection system 450 may include a number of layers, such as a wicking layer 458 and a dye layer 460. Wicking layer 458 may be formed from a wicking material capable of providing wicking action or the ability to draw another substance (in this case, moisture) into itself. The capillary layer 458 may have a predetermined color when dry and no foreign substance is drawn therein. For example, the wicking layer 458 can have a "non-wicking" color, which is generally white, but can also be gray, light, etc. To emphasize the color change when exposed to moisture, an ink layer 462 that partially obscures the wicking layer 458 can be provided. The ink layer 462 can be colored to contrast the "capillary action" color of the capillary layer 458 to provide a better viewing experience, especially when viewed through a small opening as represented by the audio jack port 42. For example, if the "non-capillary" color of the capillary layer 458 is white, the ink layer 462 can be a matching white color such that when the capillary layer 458 changes color, the color change will be opposed by the unchanged color of the ink layer 462, thereby making the color change more noticeable even through the small opening represented by the audio jack port 42.

In the illustrated embodiment, the dye layer 460 can be disposed adjacent to the wicking layer 458. The dyed layer 460 may be formed with a dry dye or a coloring substance of a predetermined color (generally, red). When the dyed layer 460 dries, the wicking layer 458 does not have the ability to wick, so that the two remain separated. Once the dyed layer 460 becomes wet or wet, the dry dye becomes wet and wicks into the wicking layer 458. As such, the wicking layer 458 can become visible through the viewing port 452 with a shape influenced by the ink layer 462, wherein the dye has a color that contrasts with a color of the ink layer 462. When no moisture penetrates into the dry dye, the wicking layer 458 appears to have a dry color, such as white, through the viewing port 452 because no wicking occurs. However, when moisture penetrates into the dry dye, the now wet dye wicks into and through the wicking layer 458 such that the color of the dye entering the wicking layer 458 becomes apparent through the viewing port 452. Once the dye wicks into wicking layer 458, the dye remains in wicking layer 458 even after wicking layer 458 dries.

Fig. 19 illustrates an external view of the moisture detection system 450.

To facilitate placement of audio jack assembly 420 on PCB404, assembly tool 470 may be used to support and align audio jack assembly 420 on PCB 404. Thus, fig. 20 shows a panel 472 formed from multiple PCBs connected together with lugs 474. As is well known in the art, printed circuit boards are typically prepared in bulk in the form of a sheet or sheet of printed circuit boards held together by panel tabs. After all appropriate circuits and accessories have been mounted on the board-like PCB, the integrated circuits and accessories may be electrically connected to the traces in the PCB using a variety of connection processes, such as soldering using a wave soldering process. However, prior to the attachment process, the audio jack assembly 420 may be placed on the PCB404 without substantial support. As such, the audio jack fitting may move or otherwise become misaligned prior to or during the welding process.

Thus, audio jack assembly 420 may be placed and temporarily secured to individual PCBs in PCB panel 472 using assembly process 470. The assembly tool 470 may take the form of a post that can be placed in the port 48, the port 48 having a length such that the post can extend completely through the audio jack barrel 422 (also referred to as "piercing"). In this manner, assembly tool 470 can be supported by ledge structure 478 and PCB 404. In this way, the assembly tool 470 can support each of the panel PCBs. In this way, the audio jack assembly 420 can be surface mounted to a corresponding plate PCB while being supported by the assembly tool 470. After audio jack accessory 420 is successfully surface mounted, assembly tool 470 may be removed and discarded.

Referring now to fig. 21 and 22, the hold switch assembly 500 is shown in greater detail in accordance with the illustrated embodiment. The hold switch assembly 500 may include a hold switch carrier 502. The retention switch carrier 502 may be formed from any suitable resilient material, such as plastic. To minimize the intrusion of moisture from the external environment through the retention switch carrier 502, a retention switch carrier seal 504 may be placed on the retention switch carrier 502. The retention switch carrier seal 504 may be formed from a water-resistant material such as silicone rubber. As such, retaining switch carrier seal 504 may have a shape that fits closely within retaining switch carrier 502. Further, the holding switch carrier seal 504 may have a plurality of openings that allow passage of the mechanical actuator. For example, an opening 506 in the hold switch carrier seal 504 can receive the playlist button 44. However, to minimize the possibility of moisture entering the interior of the media player 10, the playlist button plunger 508 extending from the playlist button 44 to the playlist contact switch 412 may pass through the retaining switch carrier seal 504 through the opening 510, effectively sealing the playlist button plunger 508, leaving little room for moisture to enter the interior of the media player 10 from the external environment.

To further reduce the likelihood of moisture entering the interior of the media player 10, a hold switch arm 512 attached at one end to the hold switch button 38 and at the other end to the hold switch side actuating contact switch 414 may pass through a slot 514 formed in a hold switch closure block 516. The hold switch closing block 516 may be formed of an elastic material such as silicone rubber and may be tightly fitted in the carrier 502. The portion of the retaining switch arm 512 that the pressure applied to the closing block 516 presses the silicone rubber in the slot 514 significantly affects the movement of the arm 512. In this way, any moisture present in the retention button 38 can be prevented from entering the interior of the media player 10.

It should be noted that in some cases it may be advantageous from an ESD mitigation standpoint to dope the silicone rubber of the enclosed mass 516 with a conductive material, such as the silver balls 518 shown in fig. 23. A conductive path 520 can be provided from hold switch 38 to chassis ground at housing 100 via arm 512. In this way, any charge at or near the hold switch 38 can be conducted to chassis ground in the form of the housing 100. It should be noted, however, that in order to provide good electrical contact at the housing 100, a portion of the surface layer of the housing 100 (if any) must be removed to expose the metal matrix. For example, where the housing 100 is formed from anodized aluminum, the laser etched portion 522 of the housing 100 can provide good electrical contact for the doped, and thus electrically conductive, seal 516.

Fig. 24 shows another embodiment of a retention switch assembly 500 in which a conductive path 524 may be provided between the retention switch button 38 and the housing 100. The metal label 40 may be attached to the retention switch arm 512 with a conductive adhesive along the solder lines forming the conductive layer 526 between the metal label 40 and the retention switch arm 512. In this manner, the charge on the hold switch button 38 may be directed along the conductive path 524 to the housing 100. However, to ensure that good electrical contact is maintained between the switch arm 512 and the housing 100, the portion 114 of the housing 100 may be worn away to expose the underlying metal matrix (aluminum in this example). In one embodiment, a surface layer associated with portion 114 may be removed by laser etching an appropriate amount of the surface layer from portion 114. In this manner, hold switch arm 512 is moved so that label 38 is in direct contact with the metal matrix layer of housing 100 at laser etched portion 114.

It should be noted that in addition to providing good electrical contact, by exposing the soft aluminum under the layer of the housing 100 to the metal label 38 at portion 114, wear and damage to the label 38 is significantly reduced. For example, when the aluminum of the housing 100 is anodized, the surface layer formed is very hard to the extent that the label 38 may be scratched or otherwise damaged due to repeated sliding of the surface layer of the anodized aluminum against the housing 100 even when the label 38 is formed of stainless steel. However, when laser etched, the natural aluminum under the layer of the housing 100 exposed in the portion 114 does not significantly damage or otherwise destroy the label 38.

Due to the extremely small size of the media player 10, it can be difficult and time consuming to properly align external features, such as the playlist button 44 and the housing 100. FIG. 25 illustrates one particularly useful alignment technique for mounting and aligning the playlist button 44 (or any other external feature) in accordance with the illustrated embodiment. Specifically, fig. 25 shows PCB404 with at least a portion of ledge 478 left thereon. The playlist button 44 may include a plunger 508 that can press on the playlist contact switch 412. To minimize tolerance stack-up between playlist button 44 and housing 100, tab 478 may be laser cut at laser cut line 2502 opposite fiducial mark 2504 on PCB 404. In this way, tolerance stack-up can be greatly reduced, thereby significantly improving the look and feel of the playlist button 42.

Fig. 26 shows a flow diagram detailing an assembly process 2600 in accordance with the illustrated embodiment. By providing a housing, the assembly process can begin at 2602. The housing may be formed of metal or any other suitable material. The housing may also include a plurality of openings sized and positioned to accommodate insertion and assembly of various internal components. In the illustrated embodiment, the housing includes at least a front opening sized to receive the click wheel assembly and a rear opening sized to receive the clip assembly. In any case, the media player is assembled using what is referred to as inside-outside assembly techniques, described in more detail below. Once the housing is provided, a fully assembled and functionally tested input device, which may take the form of a click wheel assembly, may be provided at 2604. The click wheel assembly may include a front-facing click wheel having a plurality of input features that can be activated by a user. For example, the input feature may take the form of a clickable switch that is capable of responding to a pressing event by the user by engaging an actuator arranged to generate a signal in accordance with the pressing event. The click wheel assembly may also include a dual purpose metal plate having an outwardly facing surface with a signal generating actuator and an inwardly facing surface with an attachment feature for securing an internal component, such as a main logic board assembly (MLB). At 2606, a fully assembled and functionally tested MLB may be provided. The MLB may include many integrated circuits, switches, and I/O devices. The switches may include at least a direct-actuation playlist button contact switch, and a side-actuation hold button contact switch laterally offset from the outer hold button. The MLB may also include a surface mounted audio jack assembly and a battery.

At 2608, the MLB fitting and the trolley fitting can be electrically connected to each other using a flexible connector from the trolley fitting to a zero insertion force (or ZIF) electrical connector at the MLB fitting. At 2610, the MLB assembly and the trolley wheel assembly are mechanically coupled to each other. In the illustrated embodiment, bosses on the inwardly facing surface of the metal plate of the click wheel assembly receive fasteners such as screws. Screws are used to mechanically secure the MLB assembly to the click wheel assembly. Then at 2612, the click wheel assembly/MLB assembly is inserted into the rear opening of the housing and aligned with the front opening of the housing. The playlist button and the hold button are aligned with corresponding openings in the housing, as are the audio jack units. At 2614, a dock seal is placed on the outer edge of the rear opening. The dock seal is formed of a resilient material, such as silicone rubber, that inhibits moisture/contaminants from flowing from the external environment into the media player.

The clip assembly is then inserted into the rear opening at 2616, snap-fit with the housing at 2618 using the flanges on the housing, and at about the same time, latch-fit with the latching features on the click wheel assembly at 2620.

Fig. 27 is a flowchart detailing a process 2700 for providing ESD protection in a portable device in accordance with an illustrative embodiment. Process 2700 can be used to shunt electrostatic charge that accumulates on the hold button to chassis ground (the housing in this example). Process 2700 can proceed by providing a retention button seal formed of a substantially electrically insulating material at 2702. In the illustrated embodiment, the retention button seal may be formed of an elastomeric material such as silicone rubber. Typically, the materials used to form the retention button seal are insulating in nature because they are generally not conducive to charge flow. At 2704, at least a portion of the retaining button material is made electrically conductive. In the illustrated embodiment, the change from the insulating state to the conductive state of at least a portion of the retaining button seal is accomplished by doping the portion of the retaining button material with a conductive dopant material, such as a micro silver ball. At 2706, a doped retention button seal is used to enclose a retention button arm that mechanically connects an external retention button and an internal retention button switch. At 2708, the conductive portion holding the button seal is brought into electrical contact with the chassis ground. In the illustrated embodiment, the chassis ground may take the form of a conductive housing formed, for example, from aluminum. The charge accumulated on the external hold button is then shunted from the internal hold button switch to chassis ground at 2710.

Fig. 28 is a block diagram of a media player 2800 according to an illustrated embodiment. The media player 2800 includes a processor 2802, which may be a microprocessor or controller, for controlling the overall operation of the media player 2800. The media player 2800 stores media data pertaining to media items in the file system 2804 and the cache 2806. The file system 2804 is typically a storage disk or a plurality of disks. The file system typically provides mass storage capability for the media player 2800. However, because of the long access time to the file system 2804, the media player 2800 also includes a cache 2806. The cache memory 2806 is, for example, a Random Access Memory (RAM) provided with a semiconductor memory. The relative access time to the cache 2806 is significantly smaller compared to the file system 2804. However, the cache 2806 does not have the large storage capacity of the file system 2804.

Further, the file system 2804 consumes more power when active than the cache 2806. Power consumption is particularly important when the media player 2800 is a portable media player that is powered by a battery (not shown).

Media player 2800 also includes a user input device 2808 that allows a user of media player 2800 to interact with media player 2800. For example, user input device 2808 may take various forms, such as buttons, a numeric keypad, a dial, and so forth. In addition, the media player 2800 includes a data bus 2810 that can facilitate data transfer between at least the file system 2804, the cache 2806, the processor 2802, and the CODEC 2812.

In one embodiment, the media player 2800 is used to store a plurality of media items (e.g., songs) in the file system 2804. When a user desires to have the media player play a particular media item, a list of available media items is displayed on the display 2810. The user can then select one of the available media items by utilizing user input device 2808. Upon receiving a selection of a particular media item, the processor 502 provides media data (e.g., an audio file) for the particular media item to a coder/decoder (CODEC) 2812. The CODEC 2812 then generates an audio output signal to the audio jack 2814 for output to external circuitry. For example, headphones or earphones that connect with the media player 2800 may be considered examples of external circuitry.

In another embodiment, a computer readable medium comprising computer program instructions for performing the various assembly steps illustrated in FIG. 26 is provided. In particular, the computer program instructions may be used to control various automated assembly components, such as robotic arms, automated screw drivers, and the like. This enables the equipment to be set up without (or at least with minimal) human intervention. Thus, the computer instructions can be programmed to control the machine to insert the various components into the housing substantially without human intervention. The computer instructions may also be programmed to control the machine to perform laser etching and laser routing, in addition to any other processing required for assembly and testing of the media player.

Fig. 29-32 illustrate techniques and structures well suited for forming a moisture ingress seal for audio jack fitting 420, according to the illustrated embodiments. It should be noted that although described with respect to audio jack fitting 420, the described techniques and structures may be used with almost any device that is operated and constructed in a manner such that at least one portion is water resistant, while another portion in proximity necessarily remains water-resistant. A good example of this is audio jack fitting 420, where the internal cavity 428 of the barrel 424 must be water resistant, since the audio port 42 is exposed to the external environment without any pre-treatment. For example, the portable media player 10 may be immersed in a liquid, such as water, such that water is likely to enter the internal cavity 428 through the audio port 42 (assuming, obviously, no audio terminal is inserted into the audio jack cylinder 422). The presence of water in the internal cavity 428 is generally not a problem, but the moisture ingress path 432 may provide a mechanism whereby water present in the internal cavity 428 may enter the interior of the media player 10.

Thus, water present in the lumen 428 must be effectively prevented from entering the passage 432 (or any other passage for that matter) in a cost effective and manufacturing effective manner. One particularly useful means of sealing the cavity 428 relies on forming a sealing structure that effectively prevents moisture from migrating from the cavity 428 and the interior of the media player 10. In one embodiment, a sealing structure may be used to seal electrical contacts 430. The electrical contact seal arrangement may be formed to include a main seal and a subsequently applied trim seal. In one implementation, the primary seal may be formed from a sealing band layer applied by pressure to the electrical contacts and a portion of the audio jack housing. After forming the primary seal, a trim seal may be formed in an assembly attachment process where the electrical connector is electrically connected to the exposed portion of the electrical contact. The component attachment process may take a variety of forms. However, in the illustrated embodiment, the component attachment process may take the form of Surface Mount Assembly (SMA) technology. One particularly useful SMA technique, known as solder reflow, relies on heating the solder paste associated with the flexible connector to form a liquid solder. The liquid solder may then flow in and around the joint area of the exposed portions of the flexible connector and the electrical contacts. When allowed to cool, the liquid solder solidifies in place, providing an electrically conductive path between the flexible connector and the electrical contact by way of the exposed portion. The solidified solder may also seal the area between the sealing band and the exposed portion of the electrical contact. In this manner, the solder may provide a mechanism for forming an electrical connection and sealing the electrical connection, thereby providing a cost-effective and manufacturing-effective operation well suited for enhancing the protection of the media player 10 from water intrusion.

Fig. 29 shows an implementation of the audio jack assembly 420 described above. In particular, fig. 29 shows an electrical contact 2902. The electrical contacts 2902 may be in physical contact with corresponding conductive rings included in an audio terminal having a size and shape that conforms to the audio jack cylinder 424. Electrical contacts 2902 may, in turn, include (flat) contact pad portions 2904 and (upward) recessed portions 2906. Pad portions 2904 may be sized to accommodate a sealing tape (or film) applied to electrical contacts 2902, such that most of recessed portions 2906 remain exposed and free of sealing tape. For example, as shown in fig. 30, the primary seal may take the form of a seal strip layer 2908, the seal strip layer 2908 may be created by applying a sealing strip to the audio jack body 422 and the contact pad portion 2904. In this way, most of the recessed portion remains exposed. The sealing strip may take a variety of forms. For example, the sealing tape may be along kapton^TMA pressure applying band of wire. Once the sealing tape layer 2908 is formed, a flexible substrate 2910 may be overlaid onto the sealing tape layer 2908, as shown in fig. 31.

During a subsequent solder reflow process that electrically connects the flexible substrate 2910 to the electrical contacts 430 through the recessed portion 2906, a trim seal may be formed using solder paste associated with the flexible substrate 2910. In this embodiment, the solder paste may be heated to at least its melting point to form a liquid solder. Solder, now in liquid form, can flow into the junction region 2912 between the recessed portion 2906 and the sealing tape layer 2908. Free flowing solder may fill any gaps and voids between the recessed portion 2906 and the seal tape layer 2908. For example, the engagement region 2912 may include a gap or void that would provide an intrusive path for water to enter the interior of the media player 10. Thus, by allowing liquid solder to fill these gaps and voids in the joint region 2912, the solder flowing in the joint region 2912, while allowing cooling and return to a solid body, may form a seal 2914, which seal 2914 effectively prevents any water ingress with the joint region 2912. In this way, the seal 2914 may effectively seal the electrical contacts 2902 from water passing through the interior portion 428 and the interior of the media player 10.

FIG. 32 shows a flowchart detailing a process 3200 according to an illustrated embodiment. Process 3200 may be implemented by providing an audio jack assembly at 3202. Next, at 3204, a primary moisture ingress seal is formed by applying a sealing tape layer to the electrical contacts of the audio jack fitting. The electrical contacts are formed by flat pad areas and protruding portions, called recesses. In the illustrated embodiment, the recess remains exposed. Next, at 3206, a flexible substrate is applied to the housing in direct contact with only the recesses of the electrical contacts, and the flat pad portions are protected by a sealing tape applied thereon. Next, at 3210, a trim seal is formed by performing a solder reflow operation on the audio jack fitting. The solder reflow operation causes solder paste associated with the flexible substrate to electrically connect the flexible substrate with the electrical contacts via the recesses. The solder reflow process also flows solder paste into the recess surrounding the recessed portion. When the solder solidifies, the solidified solder seals the recess, sealing band, and housing, preventing water intrusion into the media player through the audio jack contact.

Various aspects, embodiments, implementations or features of the illustrative embodiments may be used alone or in combination. Aspects of the illustrated embodiments may be implemented in software, hardware, or a combination of hardware and software. The illustrated embodiments may also be embodied as computer readable code on a computer readable medium that controls the manufacturing operation or as computer readable code on a computer readable medium that controls a manufacturing line. The computer readable medium is any data storage device that can store data which can thereafter be read by a computer system. Examples of the computer readable medium include read-only memory, random-access memory, CD-ROMs, DVDs, magnetic tape, and optical data storage devices. The computer readable medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the embodiments of the invention. However, it will be apparent to one skilled in the art that these specific details are not required in order to practice the present invention. Accordingly, the foregoing descriptions of specific embodiments are presented for purposes of illustration and description. The foregoing description is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obviously, many modifications and variations are possible in light of the above teaching to those skilled in the art.

Claims (18)

1. A consumer electronic product comprising:

a one-piece housing formed of aluminum having integral front and side walls cooperating with the front opening to form a cavity, edges of the side walls defining a rear opening, wherein at least some of the edges have a flange, wherein at least one of the side walls includes an opening sized to receive an I/O device;

a clip assembly having a size and shape that conforms to the rear opening, the clip assembly having a plurality of attachment features for securing the clip assembly to the one-piece housing; and

a plurality of moisture barriers, each of the plurality of moisture barriers formed of a waterproof material, wherein the plurality of moisture barriers cooperatively inhibit moisture from moving into the cavity from an external environment, wherein at least one of the plurality of moisture barriers is an audio jack fitting electrical contact moisture barrier, comprising:

an electrical contact comprising a flat pad portion and a central protrusion portion, the electrical contact being integrally formed with the housing of the audio jack fitting;

a sealing tape layer applied to an outer case of an audio jack fitting, combined with a pad portion of the electric contact part and exposing the protrusion part;

a flexible substrate layer, wherein the flexible substrate layer is electrically connected to the electrical contacts by way of the raised portions by subjecting the audio jack assembly to a solder reflow process that causes liquid solder to enter and fill recessed areas between the raised portions, sealing band, and the flexible substrate layer, the solder-filled recessed areas providing a moisture intrusion barrier between an external environment and an interior portion of the consumer electronic product.

2. A consumer electronic product as recited in claim 1, wherein said sealing tape is Kapton^TM。

3. A consumer electronic product as recited in claim 1, wherein another of the plurality of moisture barriers comprises a preformed cover formed of a waterproof material, the preformed cover being shaped and sized to fit over at least a portion of the audio jack assembly, the preformed cover being attached to the covered portion of the audio jack assembly using an adhesive.

4. A consumer electronic product as recited in claim 1, further comprising:

a moisture inhibiting sealing structure for use in an electrical assembly of an electrical system that prevents moisture from flowing from a water-tolerant portion of the electrical assembly to a non-water-tolerant portion of the electrical system, the moisture inhibiting sealing structure comprising:

a primary seal structure for providing a first seal layer; and

a trim seal structure applied to the main seal structure, wherein the trim seal structure cooperates with the main seal structure to prevent moisture from flowing between a water-tolerant portion of the electrical assembly and a non-water-tolerant portion of the electrical system.

5. A consumer electronic product as recited in claim 4, wherein the electrical component is an audio jack assembly.

6. A consumer electronic product as recited in claim 4, wherein the electrical system is a portable media device.

7. A consumer electronic product as recited in claim 4, wherein the primary sealing structure is a pressure application tape layer.

8. A consumer electronic product as recited in claim 4, wherein the trim seal structure is formed by reflowing solder, the reflowed solder being used to fill gaps in the primary seal structure.

9. A method of forming an audio jack assembly, comprising:

providing an audio jack assembly, the audio jack assembly comprising:

an audio jack cartridge having a size and shape conforming to an audio terminal connected to an external circuit;

a plurality of electrical contacts integrally formed with the audio jack barrel, the electrical contacts formed by a flat pad portion and a protrusion portion;

applying a sealing tape layer to the electrical contacts such that the sealing tape forms a layer over the pad portions and exposes the protruding portions;

applying a flexible substrate on the sealing tape layer; and

electrically connecting the flexible substrate to the electrical contacts by way of the protruding portions, wherein the electrical connection is made by performing a solder reflow operation on the audio jack assembly such that solder paste associated with the flexible substrate liquefies and flows into recessed portions between the protruding portions of the electrical contacts and the sealing strip, wherein when the solder solidifies, the solidified solder forms a water-blocking seal that prevents moisture from flowing out of the audio jack barrel through the sealed plurality of electrical contacts.

10. The method of claim 9 wherein the sealing tape is Kapton^TM。

11. The method of claim 9, wherein the water-blocking seal prevents moisture from flowing out of the audio jack barrel through the sealed plurality of electrical contacts when the audio jack barrel is submerged to a depth of about 1 meter.

12. The method as recited in claim 9, further comprising:

detecting moisture in the cavity through a moisture detection system; and

it is determined whether the moisture detected in the cavity is due to abusive behavior.

13. The method of claim 12, wherein the moisture detection system is disposed in the cavity proximate to the audio jack fitting.

14. The method of claim 13, wherein the moisture detection system comprises water indicia visible from an interior of the audio jack fitting.

15. An audio jack fitting, comprising:

an audio jack cartridge having a size and shape conforming to an audio terminal connected to an external circuit;

a plurality of electrical contacts integrally formed with the audio jack barrel, the electrical contacts formed by a flat pad portion and a protrusion portion;

a sealing tape layer applied over the pad portion of the electrical contact portion and exposing the protrusion portion; and

a flexible substrate applied on the sealing tape layer and electrically connected to the electrical contacts by means of the protruding portions, wherein the electrical connection is made by performing a solder reflow operation on the audio jack assembly such that solder paste associated with the flexible substrate liquefies and flows into recessed portions between the protruding portions of the electrical contacts and the sealing tape, wherein when the solder solidifies, the solidified solder forms a water-blocking seal that prevents moisture from flowing out of the audio jack barrel through the sealed plurality of electrical contacts.

16. The audio jack assembly of claim 15 wherein the sealing tape layer is Kapton ™^TM。

17. The audio jack fitting of claim 15, wherein said water-blocking seal prevents moisture from flowing out of said audio jack barrel through the sealed plurality of electrical contacts when said audio jack barrel is submerged to a depth of about 1 meter.

18. The audio jack fitting of claim 15 further comprising a moisture detection system disposed in the cavity proximate the audio jack fitting.