PATENT DOCUMENT

Publication Number: US-10466047-B2
Application Number: US-201615263316-A
Country: US
Kind Code: B2

Title: Barometric sensor integration in a water resistant electronic device

Abstract:
An electronic device having a pressure sensor configured to determine pressure is disclosed. The electronic device includes an enclosure defining an internal volume. The enclosure may include a sidewall with an external opening that provides a vent for the internal components. To reduce the response of the pressure sensor (that is, the time required to detect a pressure change), the pressure sensor may secure with an internal wall of the enclosure. Further, the internal wall includes an opening defining an air pocket significantly smaller than the internal volume. When the pressure sensor is mounted to receive air via the air pocket, the pressure sensor may respond faster to pressure changes, as compared to receiving air circulating throughout the internal volume. This is due in part to an amount of airflow passing through the air pocket causing a greater pressure change throughout the air pocket as compared to the internal volume.

Claims:
What is claimed is: 
     
       1. An electronic device, comprising:
 an enclosure defining a first volume; 
 a pressure sensor secured to a wall of the enclosure, the pressure sensor including a diaphragm; and 
 an air-permeable membrane covering an opening in the wall to define a second volume between the diaphragm and the air-permeable membrane that is less than the first volume, wherein the pressure sensor detects pressure based on air within the second volume. 
 
     
     
       2. The electronic device of  claim 1 , wherein the enclosure comprises a second opening that allows air to flow into the first volume. 
     
     
       3. The electronic device of  claim 2 , wherein the enclosure further comprises a third opening that allows air to flow into the first volume and the second volume. 
     
     
       4. The electronic device of  claim 1 , wherein the air-permeable membrane is water-resistant. 
     
     
       5. The electronic device of  claim 1 , wherein the enclosure comprises:
 an external sidewall having an external opening, the wall being disposed behind the external opening within the enclosure. 
 
     
     
       6. The electronic device of  claim 5 , further comprising an operational component that uses the external opening for audio transmission. 
     
     
       7. The electronic device of  claim 1 , wherein the pressure sensor detects pressure based on flexure of the diaphragm. 
     
     
       8. An electronic device, comprising:
 an enclosure comprising a rear wall and sidewalls that combine with the rear wall to define an internal volume, the sidewalls including a sidewall having an external opening, the enclosure further comprising an internal wall covered by the sidewall and having an internal opening; and 
 a pressure sensor secured within the enclosure proximate the internal opening, wherein the pressure sensor combines with the internal opening and an air-permeable membrane covering the internal opening to define an air pocket having a volume less than the internal volume, and wherein the pressure sensor is configured to detect air pressure based on air within the air pocket. 
 
     
     
       9. The electronic device of  claim 8 , wherein the internal wall comprises a second internal opening, the second internal opening covered by the air-permeable membrane. 
     
     
       10. The electronic device of  claim 8 , wherein the pressure sensor comprises a diaphragm that bends in response to a pressure change within the air pocket. 
     
     
       11. The electronic device of  claim 8 , further comprising an operational component disposed between the sidewall and the internal wall, the operational component positioned to use the external opening for audio transmission. 
     
     
       12. The electronic device of  claim 11 , wherein the operational component comprises a microphone. 
     
     
       13. The electronic device of  claim 11 , wherein the operational component comprises an audio speaker. 
     
     
       14. A method for forming an electronic device having an enclosure comprising a rear wall and sidewalls that combine with the rear wall to form a first volume, the sidewalls comprising a sidewall having a first opening, the enclosure further comprising an internal wall hidden by the sidewall and having a second opening, the method comprising:
 providing a pressure sensor secured within the internal wall at the second opening; and 
 covering the second opening with an air-permeable membrane defining a second volume between the pressure sensor and the air-permeable membrane that is less than the first volume, wherein the pressure sensor detects pressure based on air within the second volume. 
 
     
     
       15. The method of  claim 14 , wherein the air-permeable membrane is water-resistant. 
     
     
       16. The method of  claim 14 , wherein the pressure sensor detects pressure based on air entering and exiting the second volume through the air-permeable membrane. 
     
     
       17. The method of  claim 16 , wherein the second volume is bound by the air-permeable membrane, the second opening, and the pressure sensor. 
     
     
       18. The method of  claim 14 , wherein the air-permeable membrane is adhesively secured with the internal wall by an airtight adhesive. 
     
     
       19. The method of  claim 14 , wherein the pressure sensor comprises a diaphragm that bends in response to a pressure change within the second volume.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims the benefit of priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 62/234,971, filed on Sep. 30, 2015, and titled “BAROMETRIC SENSOR INTEGRATION IN A WATER RESISTANT ELECTRONIC DEVICE,” the disclosure of which is incorporated herein by reference in its entirety. 
    
    
     FIELD 
     The following description relates to an electronic device having a pressure sensor in an enclosure, or housing, of the electronic device. In particular, the following description relates to a pressure sensor used to detect a pressure change, which may occur when the electronic device undergoes an elevation change. The pressure sensor may be positioned in the electronic device against a wall of the enclosure so as to expose the pressure sensor to a relatively small air volume. Movement of air through the small volume may result in a greater pressure change, as compared to the same amount of air moving through the enclosure, which may decrease response times of the pressure sensor to the pressure changes. As a result, the pressure sensor can more quickly detect pressure changes. 
     BACKGROUND 
     An electronic device may include sensing devices used to detect certain environmental conditions. Some sensing devices, such as pressure sensors, require an opening, or openings, in order to receive air to determine the pressure. However, by increasing the number of openings, the likelihood of exposure to liquid ingress in the electronic device increases, thereby increasing the likelihood of damage to the electronic device. 
     In order to reduce the number of openings, the pressure sensor can be centrally located within the electronic device and rely upon air from an existing opening. However, in order for the pressure sensor to accurately and quickly determine pressure sensor, air passing through the existing opening much reach the pressure sensor. This may lead to slower response times for the pressure sensor, as the pressure sensor may not determine pressure changes until the air fully circulates throughout the electronic device. 
     SUMMARY 
     In one aspect, an electronic device is described. The electronic device may include an enclosure defining a first volume. The enclosure may include an opening. The electronic device may further include a pressure sensor secured within the enclosure at the opening. The electronic device may further include a membrane covering the opening to define a second volume less than the first volume. In some embodiments, the pressure sensor detects pressure based on air within the second volume. 
     In another aspect, an electronic device is described. The electronic device may include an enclosure that includes a rear wall and sidewalls that combine with the rear wall to define an internal volume. The sidewalls may include a sidewall having an external opening. The enclosure may include an internal wall covered by the sidewall and having an internal opening. The electronic device may further include a pressure sensor secured with the enclosure at the internal opening. In some embodiments, the pressure sensor combines with the internal opening to define an air pocket having a volume less than the internal volume. Also, in some embodiments, the pressure sensor is configured to detect air pressure from air entering the air pocket. 
     In another aspect, a method for forming an electronic device is described. The electronic device may include an enclosure that includes a rear wall and sidewalls that combine with the rear wall to form a first volume. The sidewalls may include a sidewall having a first opening. Also, the enclosure may further include an internal wall hidden by the sidewall and having a second opening. The method may include providing a pressure sensor secured within the internal wall at the opening. The method may further include covering the second opening with a membrane defining a second volume less than the first volume. In some embodiments, the pressure sensor detects pressure based on air within the second volume. 
     Other systems, methods, features and advantages of the embodiments will be, or will become, apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description and this summary, be within the scope of the embodiments, and be protected by the following claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure 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  illustrates a front view of an embodiment of an electronic device, in accordance with the described embodiments; 
         FIG. 2  illustrates a side view of the electronic device shown in  FIG. 1 , showing several openings of the enclosure; 
         FIG. 3  illustrates a partial cross sectional view of the interior region the enclosure shown in  FIG. 2 , taken along line A-A in  FIG. 2 , showing the internal openings; 
         FIG. 4  illustrates a cross sectional view of the electronic device shown in  FIG. 2 , further showing the electronic device having a pressure sensor secured with the internal wall; 
         FIG. 5  illustrates a cross sectional view of an alternate embodiment of an electronic device, showing an operational component and a pressure sensor sharing an opening of the enclosure, in accordance with the described embodiments; 
         FIG. 6  illustrates a side view of an alternate embodiment of an electronic device, showing an enclosure having a sidewall and a membrane secured the sidewall; 
         FIG. 7  illustrates a partial cross sectional view of the electronic device shown in  FIG. 6 , taken along line B-B in  FIG. 3 , showing the openings of the sidewall; 
         FIG. 8  illustrates a cross sectional view of an alternate embodiment of an electronic device, showing the pressure sensor disposed behind an operational component, in accordance with the described embodiments; 
         FIG. 9  illustrates a cross sectional view of an alternate embodiment of an electronic device, showing a pressure sensor and a membrane secured with an enclosure of the electronic device; and 
         FIG. 10  illustrates a flowchart showing a method for venting an electronic device having an enclosure having a first opening and a second opening, in accordance with the described embodiments. 
     
    
    
     Those skilled in the art will appreciate and understand that, according to common practice, various features of the drawings discussed below are not necessarily drawn to scale, and that dimensions of various features and elements of the drawings may be expanded or reduced to more clearly illustrate the embodiments of the present invention described herein. 
     DETAILED DESCRIPTION 
     Reference will now be made in detail to representative embodiments illustrated in the accompanying drawings. It should be understood that the following descriptions are not intended to limit the embodiments to one preferred embodiment. To the contrary, it is intended to cover alternatives, modifications, and equivalents as can be included within the spirit and scope of the described embodiments as defined by the appended claims. 
     In the following detailed description, references are made to the accompanying drawings, which form a part of the description and in which are shown, by way of illustration, specific embodiments in accordance with the described embodiments. Although these embodiments are described in sufficient detail to enable one skilled in the art to practice the described embodiments, it is understood that these examples are not limiting such that other embodiments may be used, and changes may be made without departing from the spirit and scope of the described embodiments. 
     The following disclosure relates to an electronic device having a pressure sensor, or barometric sensor, disposed in an enclosure of the electronic device. The pressure sensor is designed to monitor pressure, including pressure changes, exerted on the electronic device. In order to do, the enclosure includes an opening to receive ambient air. During a pressure change, air enters or exits the opening, causing the pressure sensor to detect the pressure change. When the pressure sensor is centrally located, or approximately centrally located, in the enclosure, the air must pass through the opening, during a pressure increase, to reach the pressure sensor. This may result in a time delay, as a sufficient amount of airflow is required for the pressure sensor to determine a pressure change. Conversely, a sufficient amount of air is required to exit the enclosure, during a pressure decrease, through the opening before the pressure sensor determines a pressure change. 
     Rather than requiring ambient air to circulate throughout the internal volume of the enclosure, in the present embodiments, the pressure sensor can be mounted in the enclosure such that the pressure sensor is exposed to a relatively small volume, as compared to the internal volume of the enclosure. As an example, the pressure sensor can be mounted to an opening in a sidewall or an internal wall of the enclosure, with the opening used to define in part the small volume. The small volume may be designed to include a volume that is approximately one-tenth the volume defined by the internal volume of the enclosure. In this regard, an amount of air volume required to pass into or out of the small volume to cause a pressure change registered by the pressure sensor can be significantly reduced. This is due in part to an amount of air passing through the small volume causing a greater pressure change as compared to the same amount of air passing through the internal volume. Accordingly, the small volume can contribute to decreased response time, or a smaller delay, of the pressure sensor so that the pressure sensor reacts more quickly to pressure changes. 
     In some embodiments, the sidewall includes an external opening that provides a vent for the electronic device. Further, the enclosure may include an internal wall having several internal openings, each of which can receive air via the external opening. For example, the internal wall may include a first internal opening. The pressure sensor may be mounted to the internal wall such that the first internal opening forms a small volume to receive air used by the pressure sensor to determine a pressure change. The internal wall may also include a second internal opening that allows air to circulate throughout an internal volume of the electronic device defined by the enclosure. Accordingly, the first internal opening may form in part a small volume, compared to the internal volume, and only a small amount of air is required to pass through the small volume for the pressure sensor to determine a pressure change. 
     Also, in order to prevent water from passing through the internal openings, an air-permeable, water-resistant membrane may cover the internal openings. Accordingly, the membrane may prevent damage caused by ingress of liquids that would otherwise continue through the aforementioned internal opening, while also allow air to vent through both the internal volume of the enclosure and the small volume used by the pressure sensor. Further, the membrane may be adhesively secured with the enclosure by an airtight adhesive, thereby separating the first internal opening from the second internal opening. 
     An electronic device that provides a small volume used by the pressure sensor may include several advantages. For instance, a user may use the electronic device as an activity tracker. The activity tracker may run a software application, or “app,” that determines an activity level based upon the user&#39;s activities. The activity level may depend in part on the user&#39;s elevation. In order to more accurately determine the user&#39;s activity levels, it may be useful for the electronic device to respond quickly to elevation changes, which is related to pressure changes, as air pressure tends to decrease with increased elevation, and increase with decreased elevation. The pressure sensor, exposed to a relatively small volume of air, may respond more quickly to air pressure changes, making it more responsive to elevation changes. Accordingly, when the software application uses the elevation to determine the user&#39;s activity levels, the pressure sensor may provide the software application with a faster pressure determination. 
     These and other embodiments are discussed below with reference to  FIGS. 1-10 . However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these Figures is for explanatory purposes only and should not be construed as limiting. 
       FIG. 1  illustrates a plan view of an embodiment of an electronic device  100 , in accordance with the described embodiments. In some embodiments, the electronic device  100  is a tablet device. In other embodiments, the electronic device  100  is a mobile wireless communication device, such as a smartphone. Still, in other embodiments, the electronic device  100  is a wearable electronic device, similar to a watch. When the electronic device  100  is a wearable electronic device, the electronic device  100  may include one or more bands (not shown) designed to wrap around an appendage (a wrist, for example) of a user. 
     As shown, the electronic device  100  may include an enclosure  102 . In some embodiments, the enclosure  102  is formed from a metal, which may include aluminum, stainless steel, or ceramic, as non-limiting examples. In other embodiments, the enclosure  102  includes a metal alloy. The enclosure  102  may include a rear wall that joins with several sidewalls to form an internal cavity, or internal volume, designed to carry several operational components (not shown), such as a speaker module, a microphone, a processor circuit, a memory circuit, and a battery, as non-limiting examples. The electronic device  100  may further include a display assembly  104  (shown as a dotted line) designed to present visual information. The display assembly  104  may include a touch-sensitive display assembly designed to respond to a capacitive coupling with the display assembly  104 . The electronic device  100  may further include a protective cover  106  that overlays the display assembly  104 . The protective cover  106  may include a material, such as glass or sapphire, that provides a transparent protective layer for the display assembly  104 . 
     Also, the electronic device  100  may include one or more input features, such as a first input  108  and a second input  110 . The first input  108  and/or the second input  110  may include a dial designed to rotate and provide an input to the electronic device  100  by rotation. Alternatively, or in combination, the first input  108  and/or the second input  110  may include a button designed to depress, in response to a force, in a direction toward the enclosure  102  and provide an input to the electronic device  100  by the depression. The first input  108  and/or the second input  110  may be used to generate an input or command to a processor circuit (not shown) in the electronic device  100 . In response to the input or command, the processor circuit may use an executable program stored on a memory circuit (not shown) to change the visual information displayed on the display assembly  104 . Also, the electronic device  100  may include one or more radio circuits (not shown) that provide the electronic device  100  with wireless communication capabilities, through means such as Bluetooth or 802.11 (Wi-Fi) protocol, to connect to a network as well as pair with an additional electronic device. 
       FIG. 2  illustrates a side view of the electronic device  100  shown in  FIG. 1 , showing several openings of the enclosure  102 . The display assembly  104  and the protective cover  106  (both shown in  FIG. 1 ) are removed. As shown in the enlarged view, the enclosure  102  includes a sidewall  112  having an external opening  122 . An “external opening” may be referred to as an opening through an exterior surface of the enclosure  102 , such as a sidewall opening, with the exterior surface being visible when viewing the electronic device  100 . In some embodiments, the external opening  122  provides a pathway for acoustical energy in the form of audible sound from a speaker module (not shown) disposed in the enclosure  102 . In other embodiments, the external opening  122  is used for an operational component, such as a microphone designed to capture acoustical energy through the external opening  122 . Also, in some embodiments, the enclosure  102  includes at least two openings, each of which may be designed for use with a speaker module and a microphone in a manner previously described. 
     The enclosure  102  may further include several internal openings. For example, as shown in the enlarged view, the enclosure  102  may include a first internal opening  124 , a second internal opening  126 , and a third internal opening  128 . An “internal opening” may be referred to as an opening through an internal wall located in an internal volume  130  of the enclosure  102  (denoted by the dotted line  132 ) and covered or hidden by the sidewall  112 . The aforementioned internal openings are shown as dotted lines and positioned behind a sidewall of the enclosure  102 , and accordingly, are not visible when viewing the electronic device  100  (when the electronic device  100  is assembled). 
     The external opening  122  may open to both the first internal opening  124 , the second internal opening  126 , and the third internal opening  128 , and accordingly, the external opening  122  may allow airflow into or out of the aforementioned internal openings. In some embodiments, the first internal opening  124 , in conjunction with the external opening  122 , provides a vent for use with a pressure sensor (not shown). For example, the pressure sensor is exposed to ambient air by way of the external opening  122  and the first internal opening  124 . Moreover, the first internal opening  124  may allow airflow only to the aforementioned pressure sensor. This will be shown below. Also, in some embodiments, the second internal opening  126  and the third internal opening  128 , in conjunction with the external opening  122 , provide a vent to the internal volume  130  of the enclosure  102 . In this regard, the internal volume  130  is exposed to ambient air by way of the external opening  122 , the second internal opening  126 , and the third internal opening  128 . 
       FIG. 3  illustrates a partial cross sectional view of the enclosure  102  shown in  FIG. 2 , taken along line A-A in  FIG. 2 , showing the internal openings. As shown, the first internal opening  124 , the second internal opening  126 , and the third internal opening  128  are formed in an internal wall  114  that is covered by the sidewall. Accordingly, the sidewall  112 , representing an exterior surface of the enclosure  102 , may cover the first internal opening  124 , the second internal opening  126 , and the third internal opening  128 . Also, the first internal opening  124  is generally cylindrical in shape. However, the shape (and size) of the first internal opening  124  may vary. In particular, the first internal opening  124  may include a size and a shape to accommodate a pressure sensor. This will be shown below. The second internal opening  126  and the third internal opening  128  may be disposed in a grooved region of the interior region of the enclosure  102 , as shown in  FIG. 2 . Also, the second internal opening  126  and the third internal opening  128  may open to the internal volume  130  of the enclosure  102  (shown in  FIG. 2 ). 
     The dotted lines shown in  FIG. 3  depict various paths of airflow the first internal opening  124 , the second internal opening  126 , and the third internal opening  128 . Each of the aforementioned internal openings may receive air from the external opening  122  (shown in  FIG. 2 ). Also, air passing through the first internal opening  124  may define a vent or air path used with the aforementioned pressure sensor, while air passing through the second internal opening  126  and/or the third internal opening  128  may define a vent or air path for the internal volume  130  (shown in  FIG. 2 ). While a discrete number of internal openings are shown, several additional internal openings (not shown) may be used. Also, in some embodiments, the second internal opening  126  is formed in the grooved region allowing the air to pass directly into the internal volume  130 , while the third internal opening  128  is formed in a lateral surface of the grooved region such that the air takes a lateral path to enter the internal volume  130 . 
       FIG. 4  illustrates a cross sectional view of the electronic device  100  shown in  FIG. 2 , further showing the electronic device  100  having a pressure sensor  140  secured with the internal wall  114 . For purposes of simplicity, several internal components are removed from the electronic device  100 . As shown in the enlarged view, the pressure sensor  140  includes a diaphragm  142  designed to bend or flex in response to air pressure, including changes in air pressure. For example, the diaphragm  142  may bend away from the internal wall  114  during a pressure increase, and may bend toward the internal wall  114  during a pressure decrease. Further, the pressure sensor  140  is secured and aligned with the internal wall  114  such that the diaphragm  142  is exposed to air via the first internal opening  124  (in conjunction with the external opening  122 ). Also, air entering or exiting the external opening  122  may also enter or exit, respectively, the internal volume  130  by way of the second internal opening  126  and/or the third internal opening  128 . 
     The internal wall  114  may include a membrane  150  covering the first internal opening  124 , the second internal opening  126 , and the third internal opening  128 . In some embodiments, the membrane  150  includes a water-resistant membrane designed to allow air, but not water, through the material defining the membrane  150 . In this regard, the membrane  150  may be formed from polytetrafluoroethylene (“PTFE”). Also, the membrane  150  may be formed from a Teflon material. The membrane  150  may be secured with the internal wall  114  by a first adhesive layer  152 . Also, the pressure sensor  140  may be secured with the internal wall  114  by a second adhesive layer  154 . The first adhesive layer  152  and the second adhesive layer  154  may include an airtight adhesive. As shown, the first adhesive layer  152  and the second adhesive layer  154  are positioned to separate air (received by the external opening  122 ) flowing into (or out of) the first internal opening  124  from air flowing into (or out of) the second internal opening  126  and the third internal opening  128 . In this manner, air received through the first internal opening  124  and the membrane  150  passes directly to the pressure sensor  140 , and air passing through the second internal opening  126  and/or the third internal opening  128  flows into the internal volume  130 . In addition, the membrane  150  may be further adhesively secured with the internal wall  114  by a third adhesive layer  156  that extends around the internal openings. The third adhesive layer  156  may include a waterproof adhesive designed to combine with the membrane  150  to shield the pressure sensor  140  and prevent liquid ingress from passing through the aforementioned internal openings. 
     In some embodiments, the pressure sensor  140  combines with the first internal opening  124  to define an air pocket  170 . The first adhesive layer  152  and the second adhesive layer  154  may also define in part the air pocket  170 . The air pocket  170  may include a volume or space that receives air passing through the membrane  150  and the first internal opening  124 . When the pressure sensor  140  is positioned next to the first internal opening  124  (as shown in  FIG. 4 ), the pressure sensor  140 , and in particular the diaphragm  142 , uses the air in the air pocket  170  to determine air pressure. 
     As illustrated in  FIG. 4 , the air pocket  170  includes a volume that is significantly less than that of the internal volume  130  of the enclosure  102 . In some instances, the size of the air pocket  170  is one-tenth, or approximately one-tenth, of the size of the internal volume  130 . As a result, the amount of air required to fill the air pocket  170  is significantly less than the amount of air required to fill the internal volume  130 . Further, assuming the rate of airflow is the same (as both the air pocket  170  and the internal volume  130  receive and expel air via the external opening  122 ), the time required to fill the air pocket  170  (or expel air from the air pocket  170 ) is significantly less than the time required to fill the internal volume  130  (or expel air from the internal volume  130 ). Accordingly, the pressure change within the air pocket  170  is greater than the pressure change within the internal volume  130 , for the same amount of air entering (or exiting) the air pocket  170  and the internal volume  130 . In this regard, by mounting the pressure sensor  140  in a manner such that the diaphragm  142  is exposed to airflow only from the air pocket  170 , the pressure sensor  140  may experience a pressure change more quickly, as the amount of air volume in the air pocket  170  required for the pressure sensor  140  to determine a pressure change is reduced. In other words, the air pocket  170  and associated increased (relatively) pressure change may cause the pressure sensor  140  to respond more quickly, and the pressure sensor  140  provides the electronic device  100  with a faster response to pressures changes. 
       FIG. 5  illustrates a cross sectional view of an alternate embodiment of an electronic device  200 , showing an operational component  230  and a pressure sensor  240  sharing an external opening  222  of the enclosure  202 , in accordance with the described embodiments. The electronic device  200  may include any feature or features previously described for an electronic device. As shown, the external opening  222  is formed in a sidewall  212 , allowing air to enter or exit the enclosure  202  via the external opening  222 . Also, the external opening  222  may be used by the operational component  230  for purposes of audio transmission. For example, as shown, the operational component  230  may include an audio speaker designed to drive audible sound through the external opening  222  by way of a porous material  232 , which may include mesh. However, although not shown, in some embodiments, the operational component  230  includes a microphone designed to receive audible sound. 
     Also, the enclosure  202  may further include an internal wall  214  and a pressure sensor  240  secured with the internal wall  214 . The internal wall  214  may include a membrane  250  covering several internal openings of the internal wall  214 . For example, the internal wall  214  may include an internal opening  224  defining an air pocket  270  that exposes the pressure sensor  240  to air passing through the external opening  222 . The membrane  250  may include a water-resistant membrane that allows to air, but not water, to pass through the membrane  250 . Accordingly, the membrane  250  may allow the electronic device  200  to take the form of a water-resistant electronic device by restricting the flow of aqueous-based solutions through the membrane  250 . 
     As shown in the enlarged view, the air pocket  270  is bounded by at least the membrane  250 , the internal wall  214 , and the pressure sensor  240 . Also, the pressure sensor  240 , and in particular, a diaphragm  242  of the pressure sensor  240 , may use the air pocket  270  to detect air pressure exerted on the electronic device  200 , with the diaphragm  242  bending or flexing in response to changes in air pressure. For example, the diaphragm  242  may bend in a direction away from a space defined by the air pocket  270  in response to a pressure increase, and may bend in a direction toward a space defined by the air pocket  270  in response to a pressure decrease. The air pocket  270  may represent a volume or space significantly smaller than that of an internal volume (not shown) of the electronic device  200 . 
     Although not shown, the pressure sensor  240  may be in electrical communication with a processor circuit of the electronic device  200 . The pressure sensor  240  may determine the pressure and send pressure information to the processor circuit. Alternatively, the pressure sensor  240  may communicate with the processor circuit by sending an electrical signal, such as several pulses of electrical current at a predetermined frequency or an analog current signal. The processor circuit may then use a program or algorithm stored on a memory circuit (not shown) to determine the pressure based upon the communication with the pressure sensor  240 . 
       FIG. 6  illustrates a side view of an alternate embodiment of an electronic device  300 , showing an enclosure  302  having a sidewall  312  and a membrane  350  secured the sidewall  312 . The display assembly and protective cover are removed. The membrane  350  may include an air-permeable, water-resistant membrane, and further, may include any material previously described for a membrane. As shown in the enlarged view, the sidewall  312  may include several external openings, each of which is covered by the membrane  350 . For example, the sidewall  312  may include a first opening  324 , a second opening  326 , and a third opening  328 . The first opening  324  may provide an air to a pressure sensor (not shown) disposed in the enclosure  302 , and in particular, an internal volume  330  of the enclosure  302 . The second opening  326  and the third opening  328  may provide a pathway for acoustical energy in the form of audible sound from a speaker module (not shown) disposed in the enclosure  302 . Alternatively, or in combination, the second opening  326  and the third opening  328  may provide a vent for the enclosure  302 . With the openings of the enclosure  302  covered by the membrane  350 , the opening may be protected from water ingress while providing air paths for the electronic device  300 . 
       FIG. 7  illustrates a partial cross sectional view of the electronic device  300  shown in  FIG. 6 , taken along line B-B in  FIG. 6 , showing the aforementioned openings of the sidewall  312 . As shown, a pressure sensor  340  is secured with the sidewall  312 . Further, the pressure sensor  340  is positioned on the sidewall  312  such that a diaphragm  342  of the pressure sensor  340  is aligned with the first opening  324 , with the diaphragm  342  designed to bend or flex in response to air passing to and from the first opening  324 . Also, air entering or exiting the second opening  326  and/or the third opening  328  may also enter or exit, respectively, the internal volume  330  (shown in  FIG. 6 ). 
     The membrane  350  may be secured with an exterior surface of the sidewall  312  by a first adhesive layer  352 . Also, the pressure sensor  340  may be secured with an interior surface of the sidewall  312  by a second adhesive layer  354 . As shown, the first adhesive layer  352  and the second adhesive layer  354  are positioned to separate air passing through the membrane  350  and flowing into (or out of) the first internal opening  124  from air flowing into (or out of) the second opening  326  and the third opening  328 . In this manner, air received through the first opening  324  passes directly to the pressure sensor  340 , and air passing through the second opening  326  and/or the third opening  328  flows into the internal volume  330 . In addition, the membrane  350  may be further adhesively secured with the sidewall  312  by a third adhesive layer  356  that extends around openings. The third adhesive layer  356  may include a waterproof adhesive designed to combine with the membrane  350  to shield the pressure sensor  340  and prevent liquid ingress from passing through the aforementioned openings. 
     The pressure sensor  340  may combine with the first opening  324  to define an air pocket  370  having a volume that is significantly less than that of the internal volume  330  of the enclosure  302 . In this regard, by mounting the pressure sensor  340  in a manner such that the diaphragm  342  is exposed to airflow only from the air pocket  370  (as compared to another location of the internal volume  330 ), the pressure sensor  340  may experience a pressure change more quickly, as the amount of air volume in the air pocket  370  required for the pressure sensor  340  to determine a pressure change is reduced. 
       FIG. 8  illustrates a cross sectional view of an alternate embodiment of an electronic device  400 , showing a pressure sensor  440  disposed behind an operational component  430 , in accordance with the described embodiments. The operational component  430  may include an audio speaker covered by a porous material  432 , such as mesh. Although not shown, the operational component  430  may include a microphone. As shown, the pressure sensor  440  is secured with an internal wall  414  of the enclosure  402  and may be positioned in a manner such that the operational component  430  is positioned between an external opening  422  (of the enclosure  402 ) and the pressure sensor  440 . As shown, the internal wall  414  may include several internal openings. For example, the internal wall  414  includes a first internal opening  424  that defines an air pocket  470  to expose the pressure sensor  440  to air received by the external opening  422 . The internal wall  414  may further include a second internal opening  426  that allows air to flow into or out of an internal volume (not shown) defined by the enclosure  402 . The internal wall  414  may also include a membrane  450  secured with the internal wall  414  by a waterproof adhesive, with the membrane  450  covering the internal openings to provide an air-permeable, water-resistant barrier that prevents the flow of aqueous-based solutions from passing through the internal openings. Also, the pressure sensor  440 , and in particular, a diaphragm  442 , may use air received by the external opening  422  and passing through the membrane  450  and the air pocket  470  to detect air pressure exerted on the electronic device  400 . Further, the air pocket  470  may include a size significantly smaller than that of the internal volume such that an amount of air passing through the air pocket  470  causes a greater pressure change in the air pocket  470 , as compared to the internal volume. Also, although not shown, the pressure sensor  440  may be mounted on a circuit board or a flexible circuit to place the pressure sensor  440  in electrical communication with a processor circuit, as a non-limiting example. In this manner, the pressure sensor  440  can communicate with the processor circuit to provide pressure information to the processor circuit in any manner previously described. 
       FIG. 9  illustrates a cross sectional view of an alternate embodiment of an electronic device  500 , showing a pressure sensor  540  and a membrane  550  secured with an enclosure  502  of the electronic device  500 . The enclosure  502  may include any feature or features previously described for an enclosure. For example, the enclosure  502  may include multiple internal openings, such as a first internal opening  524  and a second internal opening  526 , that allow air to flow into or out of the internal volume (not shown) of the electronic device  500 . Further, the enclosure  502  may form a recessed region  522  to receive the pressure sensor  540 . Also, a membrane  550  may cover the pressure sensor  540  to provide an air-permeable, water-resistant barrier that prevents the flow of aqueous-based solutions from contacting the pressure sensor  540 . Also, the membrane  550  may be adhesively secured with the enclosure  502  by way of a waterproof adhesive. The pressure sensor  540  may include a shield  510  (or can) that adhesively secures with the membrane  550  by way of an airtight adhesive. The shield  510  can provide an mechanical shield as well as electromagnetic interference (“EMI”) shield. 
     The pressure sensor  540  may further include a diaphragm  542  exposed to ambient air passing through the membrane  550 . In this regard, the shield  510  includes an opening to allow air to reach the diaphragm  542 . Also, the recessed region  522  may receive a circuit board  560  in electrical communication with the pressure sensor  540 . 
     The diaphragm  542  may be designed to actuate by bending or flexing in response to a pressure change based upon air received by the diaphragm  542  through the opening of the shield  510 . The diaphragm  542 , and other embodiments of a diaphragm described herein, may include a material or materials that bends or flexes in response to a pressure change at the diaphragm  542  approximately in the range 1-5 pounds per square inch (“psi”). Accordingly, the diaphragm  542 , and other diaphragms described herein, may bend in response to a pressure change at or within the aforementioned pressure range and/or a pressure greater than 5 psi. 
     The diaphragm  542  may be sealed with the shield  510  by, for example, a pressure sensitive adhesive, silicone rubber, a gasket or an O-ring. Also, a waterproof seal may seal the shield  510  with the circuit board  560 . In this manner, when the diaphragm  542  is formed from a waterproof material, the components of the pressure sensor  540  surrounded by the shield  510 , the diaphragm  542 , and the circuit board  560  are protected from liquid contaminants, such as water or some aqueous-based solutions. Also, the shield  510  may be electrically coupled with the circuit board  560  in order to provide at least part of an electrical grounding path for the pressure sensor  540 . 
     The pressure sensor  540  may further include a detection mechanism  544  designed to bend or flex along with the diaphragm  542  when the diaphragm  542  bends or flexes in response a pressure change. In some embodiments, the detection mechanism  544  is embedded in the diaphragm  542 . In the embodiment shown in  FIG. 9 , the detection mechanism  544  is coupled with the diaphragm  542 . Also, in some embodiments, the detection mechanism  544  is a strain gauge designed to change an electrical resistance in response to a bending or flexing of the diaphragm  542 . Accordingly, the detection mechanism  544  may receive electrical current and provide an electrical resistance that changes with the bending or flexing of the detection mechanism. In other embodiments, the detection mechanism  544  is a capacitive sensor designed to change a capacitance level in response to a bending or flexing of the diaphragm  542 . Still, in other embodiments, the detection mechanism  544  is an ultrasonic sensor that uses sound waves to detect a bending or flexing of the diaphragm  542 . In any event, the detection mechanism  544  may be designed to provide an output, including an electrical output, by bending or flexing with the diaphragm  542 . The output may be used to determine the pressure exerted on the electronic device  500 , and in particular, the diaphragm  542 . As non-limiting examples, the electrical output may take the form of an electrical pulse that varies in frequency corresponding to the amount of bending or flexing of the diaphragm  542 . Alternatively, the electrical output may take the form of an analog signal that varies in electrical current corresponding to the amount of bending or flexing of the diaphragm  542 . 
     The pressure sensor  540  may further include a processor circuit  546  designed to receive the electrical output from the detection mechanism  544 . In some embodiments, the processor circuit  546  includes a MEMS chip. As shown, the processor circuit  546  is separated from the detection mechanism  544  by a spacer element  548 . Further, the processor circuit  546  may be electrically coupled with the detection mechanism  544  via the spacer element  548 , or another feature (not shown) embedded in the spacer element  548 . The processor circuit  546  may use the electrical output from the detection mechanism  544  to determine a pressure exerted on the diaphragm  542 . Also, as shown in a partial internal view, the processor circuit  546  includes an air pocket  552  used by the processor circuit  546  as a reference pressure. In some embodiments, the air pocket  552  provides the processor circuit  546  with an absolute pressure. Accordingly, the pressure as determined by the pressure sensor  540  may be compared with a reference pressure. Also, as shown, the processor circuit  546  includes several pins  554  to electrically couple the processor circuit  546  with the circuit board  560 . Also, in some embodiments (not shown), the pressure sensor  540  includes an application-specific integrated circuit (ASIC) that executes instructions from a program or algorithm stored on the ASIC chip and combines with the processor circuit  546  to determine the pressure based on the electrical output from the detection mechanism  544 . The ASIC chip may, in some cases, substitute for the processor circuit  546 . 
     Similar to previous embodiments, the pressure sensor  540  may be provided with an air pocket  570  that includes a relatively small volume, as compared to the internal volume (not shown) of the enclosure  502 . For example, the air pocket  570  may be defined by a volume or space between the membrane  550  and the diaphragm  542 . Further, the air pocket  570  may include a size significantly smaller than that of the internal volume such that an amount of air passing through the air pocket  570  causes a greater pressure change in the air pocket  570 , as compared to the internal volume. In this manner, the diaphragm  542  is limited in exposure to a small volume such that low (or minimal) air movement can cause a relatively high pressure change, causing the diaphragm  542  to respond faster than by using air circulating throughout the internal volume of the enclosure  502 . 
       FIG. 10  illustrates flowchart  600  showing a method for forming an electronic device, in accordance with the described embodiments. The electronic device may include an enclosure having a rear wall and sidewalls that combine with the rear wall to form a first volume. The first volume is configured to carry operational components such as a processor circuit, a memory circuit, a speaker module, a microphone, and a battery, as non-limiting examples. Also, the sidewalls include a sidewall having a first opening. Also, the enclosure may further include an internal wall hidden by the sidewall and having a second opening. 
     In step  602 , a pressure sensor is provided secured within the internal wall at the second opening. The pressure sensor is configured to detect air pressure from air entering or exiting the second opening. The second opening may receive ambient air from the first opening. Further, the pressure sensor may include a diaphragm aligned with the second opening such that the diaphragm bends or flexes in response to pressure changes within the second opening. 
     In step  604 , the second opening is covered with a membrane defining a second volume less than the first volume. The membrane may include a water-resistant, air-permeable membrane designed to allow air through the membrane but prevent liquid ingress. Further, the membrane may combine with the second opening and the pressure sensor to define an air pocket. The pressure sensor may detect pressure based on air within the second volume. Further, the pressure sensor may detect pressure based on air within the air pocket. 
     The various aspects, embodiments, implementations or features of the described embodiments can be used separately or in any combination. Various aspects of the described embodiments can be implemented by software, hardware or a combination of hardware and software. The described embodiments can also be embodied as computer readable code on a computer readable medium for controlling manufacturing operations or as computer readable code on a computer readable medium for controlling 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, HDDs, 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 described embodiments. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of the specific embodiments described herein are presented for purposes of illustration and description. They are not targeted to be exhaustive or to limit the embodiments to the precise forms disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings.

Metadata:
Filing Date: 20160912
Publication Date: 20191105
Grant Date: 20191105
Priority Date: 20150930
Inventors: EHMAN, Rex T.
Lukens, William C.
PELLETIER, David M.
YANG, HENRY H.
Assignee: APPLE INC
CPC Classifications: [{"code": "G01L9/0041", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01L19/14", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01C5/06", "inventive": true, "first": true, "tree": "[]"}, {"code": "G01L19/0038", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01L19/14", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01C5/06", "inventive": true, "first": true, "tree": "[]"}, {"code": "G01L19/0038", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01C5/06", "inventive": true, "first": true, "tree": "[]"}, {"code": "G01L9/0041", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01L19/14", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01L9/0041", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01L19/0038", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 58407056