Abstract:
An acoustic porting arrangement is provided that uses sound pressure signal ports ( 202, 112 ) to enhance speaker ( 406 ) and microphone cartridge ( 402 ) performance when mounting the speaker ( 406 ) on a moveable component, such as a flip part ( 102 ) of a flip-type cellular phone ( 100 ). A speaker acoustic path ( 504 ) is incorporated into the moveable component ( 102 ) to enhance the acoustic performance of an acoustic transducer ( 406 ). A microphone acoustic pathway ( 502 ) is also created through the moveable component ( 102 ) that delivers sound pressure energy to a microphone ( 402 ) that is mounted on a base ( 104 ) when the moveable component ( 102 ) is in its closed position and covering the microphone ( 108 ). Some embodiments reuse a surface acoustic port ( 202 ) for both paths.

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to the field of acoustic systems, and more particularly relates to acoustic systems with acoustic pathways through device components. 
     BACKGROUND OF THE INVENTION 
     As the trend towards smaller acoustic devices, e.g., telecommunication products, continues, engineers are experiencing increased challenges in designing these smaller and smaller devices while maintaining acceptable acoustic performance. An example is the well known “flip phone” which can be used as a conventional cellular phone or in a high audio mode that includes both speaker phone operations as well as walkie-talkie modes (also known as dispatch modes). When operating in a high audio mode, the flip part of the phone is able to be closed and then physically blocks the microphone mounted in the base of the phone. It is desirable for such a flip phone to have the same microphone acoustic performance regardless of the position of the flip part of the phone. Stated differently, the high audio operation of such a flip phone should not appreciably vary when the flip part is open or closed. Some conventional designs provide an acoustic pathway in the form of a large gap or a groove between the flip part and the base of the phone that acts as an acoustic channel for the audio signal. An acoustic pathway can also be provided between the two parts of the closed flip phone by placing bumpers in the area between the two flip phone parts so that an air gap is provided when the flip phone is closed. Providing these gaps or groves enhances acoustic performance by preventing blockage of the microphone when the flip is closed. These gaps provided by bumpers, however, add thickness to the phone when it is in the closed position, which limits a designer&#39;s ability to produce the ever smaller, and especially thinner, acoustic devices such as flip cellular phones that are in demand. The use of bumpers can also increase the number of parts in the phone assembly. Furthermore, these bumpers and groves can cosmetically detract from the phone. 
     Therefore a need exists to overcome the problems with the prior art as discussed above. 
     SUMMARY OF THE INVENTION 
     Briefly, in accordance with the present invention, an acoustic system includes a first component having a microphone and a second component that is moveable relative to the first component. The second component is also able to be positioned in at least a first position and a second position relative to the first component. The second component also has a first wall and a second wall with the second wall being opposite the first wall. The acoustic system further has at least one acoustic transducer that is affixed to the second component. The second component also includes at least one acoustic port that is configured to pass a sound pressure signal, which is generated by the acoustic transducer, through a first wall of the second component. The second component further has at least one dual purpose acoustic port that is located on the second wall of the second component and that is configured to pass an ambient sound pressure signal that enters the at least one acoustic port to the microphone. 
     Further in accordance with the present invention, a method for coupling a sound pressure signal includes providing a first component that has a microphone and providing a second component. The first component and the second component are movable with respect to each other into at least a first position and a second position. The method further includes providing an acoustic transducer mounted on the second component. The acoustic transducer is capable of producing a sound pressure signal. The method also includes providing at least one acoustic port that is configured to pass the sound pressure signal through a first wall of the second component. The method also includes passing an ambient sound pressure signal that enters the at least one acoustic port through at least one dual purpose acoustic port on a second wall of the second component to the microphone. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views and which together with the detailed description below are incorporated in and form part of the specification, serve to further illustrate various embodiments and to explain various principles and advantages all in accordance with the present invention. 
         FIG. 1  illustrates a cellular flip-type phone according to an exemplary embodiment of the present invention in an open position. 
         FIG. 2  illustrates the cellular flip-type phone of  FIG. 1  in a closed position. 
         FIG. 3  illustrates an exploded view for part of the closed cellular flip-type phone of  FIG. 2 . 
         FIG. 4  illustrates a side cut away view for the closed cellular phone of  FIG. 2 . 
         FIG. 5  illustrates a bottom cut away view for the closed cellular phone of  FIG. 2 . 
         FIG. 6  illustrates a processing flow diagram for coupling a sound pressure signal according to an exemplary embodiment of the present invention. 
         FIG. 7  illustrates a block diagram of a cellular phone incorporating an exemplary embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting; but rather, to provide an understandable description of the invention. 
       FIG. 1  illustrates a cellular flip-type phone  100  according to an exemplary embodiment of the present invention in an open position. The cellular flip-type phone  100  includes a first component that is a phone base  104 , and a second component that is a flip part  102 . The flip part  102  is a cover part in this exemplary embodiment. The phone base  104  and the flip part  102  are moveable relative to each other around a hinge  114 . Further embodiments of the present invention incorporate two or more components that move relative to each other in various ways, such as a so-called “slider” phone where a first component is a base part and a second component is a cover part that slides along the first component to expand and contract the size of the phone and expose and conceal various elements of the phone. 
     The phone base  104  and flip part  102  in this exemplary embodiment include electronic circuits, as are described below, that support wireless voice communications. The phone base  104  of this exemplary embodiment includes a keypad  106  to allow entry of phone numbers and other phone control information for the phone. The phone base  104  of this exemplary embodiment further includes a microphone contained within a microphone protrusion  108  that protrudes above the neighboring surface of the phone base  104 , as is discussed in more detail below. 
     The flip part  102  is connected to the phone base  104  by hinge  114 . The flip part  102  is shown in this illustration in the open, or second, position. A closed position, or first position, is illustrated and described below. A flip front side  120  is illustrated in this view of the cellular flip-type phone  100 . The flip part  102  has a display  110  that in this exemplary embodiment is able to display alpha-numeric and graphical data that is either communicated over a wireless link or that is used to control the operation of the exemplary cellular phone  100 . 
     The flip part  102  further includes a dual purpose acoustic port  112  that is recessed into the flip front side  120  and that has a recess wall  122 . An acoustic transducer, described below, is located behind the dual purpose acoustic port  112  and generates sound pressure signals that correspond to, for example, audio signals received by the cellular phone  100  over a wireless link. The configuration of the dual purpose acoustic port  112  and microphone protrusion  108  allow the open cellular flip-type phone  100  to be held along the face of the user to facilitate wireless audio communications. When the flip part  102  is in its closed position, as is described in further detail below, the recess of the dual purpose acoustic port  112  accepts the protruding microphone protrusion  108 . Further embodiments of the present invention incorporate dual purpose acoustic ports that protrude above the flip front side  120  and have microphones that are recessed into the phone base  104 . Yet further embodiments of the present invention include microphones that form substantially closed acoustic pathways with other structures between their first component and second components. 
     The open cellular flip-type phone  100  is able to be used in a mode in which a relatively low level acoustic signal is produced through the dual purpose acoustic port  112  that allows the dual purpose acoustic port  112  to be held near the user&#39;s ear. A further operation mode for the open cellular flip-type phone  100  includes a high level audio mode in which a separate speaker, illustrated below in  FIG. 4 , is used to produce a higher level audio output signal. The cellular phone  100  is then able to be held away from the user&#39;s ear and face and used in either of the familiar “speakerphone” or simplex voice communications modes. Microphone within microphone protrusion  108  is also generally operated with increased sensitivity in these modes in order to facilitate operation of the cellular phone  100  in the high level audio mode. Operation in the high level audio mode can be used when the cellular phone is communicating in a speakerphone wherein voice signals are simultaneously transmitted and received over a wireless link, or in a simplex mode wherein the operator alternately selects one of transmitting and receiving voice signals over the wireless link. Simplex mode is controlled in the exemplary cellular phone  100  by pressing the Push-To-Talk (PTT) button  116 . When the PTT button  116  is pressed, acoustic signals that are detected by microphone within microphone protrusion  108  are transmitted over the wireless link and no audio signals are received. When the PTT button  116  is released, audio signals received over the wireless link are produced through a high audio level speaker (illustrated below in  FIG. 4  and located on the underside of phone base  104  in this exemplary embodiment) so that they can be heard by the user. The volume of the audio signal produced by the cellular phone  100 , either through the dual purpose acoustic port  112  or speaker, can be adjusted by volume control buttons  118 . 
       FIG. 2  illustrates the cellular flip-type phone  100  of  FIG. 1  in the closed position. The closed cellular flip-type phone  100  has its flip part  102  rotated about hinge  114 , relative to the open cellular flip-type phone discussed above, so as to lie along the top of the phone base  104  and to be in a first position. An outer flip part side  204  is illustrated in this view of the cellular flip-type phone  100 . The outer flip part side  204  is the side of the flip part  102  that is opposite the front side  120  of the flip part  102 , described above. The outer flip part side  204  includes an outer side acoustic port  202  that allows sound pressure signals from an acoustic transducer, which is internal to the flip part  102  in this exemplary embodiment and is discussed below, to be ported through the outer flip part side  204 . Providing an acoustic port on the outer flip part side  204  is beneficial in smaller cellular phones that have a correspondingly smaller flip part  102  since the reduced internal spatial volume of the closed phone can adversely impact sound quality if such an acoustic port is not provided. Larger flip-type cellular phones are better able to adequately operate without an acoustic port on the outer flip part  204  side because they have larger internal spatial volume when closed. Incorporation of the outer side acoustic port  202  on the outer flip part side  204  advantageously provides improved acoustic performance when using a smaller flip part  102 . 
     The closed cellular flip-type phone  100  further identifies two sectional views, a sectional view  4 - 4  and a sectional view  5 - 5 , which are described in detail below. 
       FIG. 3  illustrates an exploded view  300  for part of the closed cellular flip-type phone  100  of  FIG. 2 . The phone base  104 , microphone protrusion  108  and the back of the flip front side  120  of the flip part  102  are shown for the cellular phone  100 . A flip part inner support  302  is shown removed from the part supporting the front side  120  of the flip part  102 . As shown, the flip part support  302  has a number of acoustic ports to support the operation of the acoustic system of the exemplary cellular phone  100 . An acoustic transducer mounting area  312  accepts an acoustic transducer that is not shown in this illustration for clarity, but that is described below. The acoustic transducer mounting area  312  has a first acoustic transducer port  308  and a second acoustic transducer port  310  to pass sound pressure signals generated by a transducer placed in the acoustic transducer mounting area  312 . Sound pressure signals generated by a mounted transducer pass through the first acoustic transducer port  308  and the second transducer port  310  and through the dual purpose acoustic port  112  when the flip part  102  is in the open, or second, position. Sound pressure signals generated by the mounted acoustic transducer also pass through outer side acoustic port  202 . 
     The exploded view of  FIG. 3  further illustrates the sound pressure signal path that is formed from the outer side acoustic port  202  to the microphone protrusion  108  when the flip part  102  is in its closed, or first, position. When the flip part  102  is in its closed position, sound pressure signals are able to enter the outer side acoustic port  202 , pass through the first internal dual purpose acoustic port  304  and the second internal dual purpose acoustic port  306 , and then pass on through the dual purpose acoustic port  112  and on through to the microphone protrusion  108 . This arrangement provides a path from the outer side acoustic port  202  on the outer flip part side  204  to the microphone protrusion  108 , thereby providing enhanced acoustic performance when the flip part  102  is in its closed, or first position. It can also be seen from this figure that microphone protrusion  108  protrudes into the recess formed by acoustic port  112  in this exemplary embodiment. 
     The acoustic path formed by the outer side acoustic port  202 , the first internal dual purpose acoustic port  304  and the second internal dual purpose acoustic port  306 , and the dual purpose acoustic port  112  is additionally used by sound pressure signals generated by an acoustic transducer when the flip part  102  is held relatively tightly to a users ear. With the configuration of the exemplary embodiment, the acoustic path through the dual use acoustic ports ensures a consistent acoustic performance for the user without regard to how the flip part  102  is held to the ear of the user. This characteristic advantageously provides a leak tolerant design by venting pressure. The “dual purpose” ports are given that name in this specification due to the use of these ports to conduct sound pressure signals that are generated by an acoustic transducer as well as to conduct sound pressure signals received from ambient sources, such as a user&#39;s voice, from the ambient area to the microphone protrusion  108 . 
       FIG. 4  illustrates a closed cellular phone side cut away view  400  for the closed cellular phone  100  of  FIG. 2 . The side cut away view  400  corresponds to the sectional view through  4 - 4  of  FIG. 2 . The flip part  102  is shown to include the flip part inner support  302  with an acoustic transducer mounting area  312 . An acoustic transducer  406 , such as an electromagnetic speaker in the exemplary embodiment, is shown to be attached at the acoustic transducer mounting area  312 , which is part of the flip part  102 . In this exemplary embodiment, flip part  102  is a moveable component of the acoustic system of cellular phone  100 . The front of the acoustic transducer  406  is shown to be facing and in proximity to the dual purpose acoustic port  112 . The rear of the acoustic transducer  406  is mounted on the acoustic transducer mounting area  312  so that sound generated by the acoustic transducer  406  is ported through the first acoustic transducer port  308  (as illustrated in  FIG. 3 ) and the second acoustic transducer port  310  (as illustrated in  FIG. 3 ). The first acoustic transducer port  308  and the second acoustic transducer port  310  are not visible in the perspective of this figure, but are located in the flip part internal support  302 , as shown above in  FIG. 3 . Sound pressure signals generated by the acoustic transducer  406  of the exemplary embodiment pass through the first acoustic transducer port  308  and the second acoustic transducer port  310  and are then ported through the outer side acoustic port  202 . In this configuration, the outer side acoustic port  202  is an acoustic port configured to pass sound pressure signals generated by the acoustic transducer  406  through a first wall of the flip part  102 , which is a moveable component of cell phone  100 . 
     It is to be noted that the second internal dual purpose acoustic port  306 , as well as the first internal dual purpose acoustic port  304  (which is behind the second internal dual purpose acoustic port  306  in the perspective of this figure but is not explicitly visible in this figure), form an acoustical path between the outer side acoustic port  202  and the dual purpose acoustic port  112 . As is clear from this illustration, ambient sound pressure signals arriving and entering through outer side acoustic port  202  pass through the second internal dual purpose acoustic port  306  and first internal dual purpose acoustic port  304  and then through the dual purpose acoustic port  112  and are delivered directly to microphone protrusion  108 . 
     The flip part  102  is shown to be folded closed along the phone base  104  so that the flip front side  120  is in proximity to the front of the phone base  104 . The microphone protrusion  108  is shown to be protruding into the recess formed for the dual purpose acoustic port  112 . This configuration forms a substantially closed acoustic pathway  404  between the dual purpose acoustic port  112 , which is a dual purpose acoustic port in this exemplary embodiment, and the microphone protrusion  108 . This substantially closed acoustic pathway  404  is also partially formed by the flip front side  120  in the exemplary embodiment. 
     Also illustrated in this side cut away view is a microphone cartridge  402 , which is part of microphone protrusion  108  in this exemplary embodiment. A high output speaker  410  is also illustrated in this side cut away view. High output speaker  410  is used for various purposes within the cellular phone  100 , such as for call notification ringing as well as for generating acoustic output when the cellular phone is operating in a high level audio mode, as described above, in either a simplex or duplex operational mode. In the exemplary embodiment, the acoustic transducer  406  does not operate when the flip part  102  of the cellular phone  100  is in its closed, or first, position, as is illustrated in this side cut away view. High output speaker  410  is instead used to generate audio output in this configuration. 
       FIG. 5  illustrates a bottom cut away view  500  for the cellular phone  100  of  FIG. 2 . The bottom cut away view  500  corresponds to the sectional view through line  5 - 5  of  FIG. 2 . The cut away view  500  illustrates the position of microphone cartridge  402  and the microphone protrusion  108  that are mounted in the phone base  104 . The bottom cut away view  500  also illustrates the acoustic transducer  406 , and the flip part internal support  302  that are located in the flip part  102 . 
     The bottom cut away view  500  further illustrates a felt pad  506  that lines the back of the flip front side  120 . Felt pad  506  is used in the exemplary embodiment in order to, for example, prevent foreign material from entering the phone housing. The felt pad  506  helps reduce the impact of metal shavings, which are attracted to the magnet within the acoustic transducer  406  and reduce the entry of water into the phone&#39;s case. 
     Microphone acoustic paths  502  are illustrated to show the path of sound pressure signals that enter the outer side acoustic port  202 , propagate through the first acoustic transducer port  308  and the second acoustic transducer port  310 , and continue on to reach the dual purpose acoustic port  112 . These sound pressure signals then continue on through the substantially closed acoustic pathway  404  and arrive at microphone protrusion  108 . These direct microphone acoustic paths  502  provide for enhanced acoustic performance of the microphone cartridge  402  when the flip part  102  of the flip-type phone  100  is in its closed position. 
     Speaker acoustic paths  504  are illustrated to show the path of sound pressure signals that propagate from the acoustic transducer  406 , through the first acoustic transducer port  308  and the second acoustic transducer port  310 , and through the outer side acoustic port  202 . As noted above, the exemplary embodiment of the present invention does not operate the acoustic transducer  406  when the flip part is in a closed position, as illustrated in this bottom cut away view, but this acoustic path is shown in this figure for comparison to the microphone acoustic path  502 . Although the microphone acoustic path  502  and the speaker acoustic path  504  are not identical, they do share a porting of acoustic signals through the outer side acoustic port  202 . 
       FIG. 6  illustrates a processing flow diagram  600  for coupling a sound pressure signal according to an exemplary embodiment of the present invention. The coupling of a sound pressure signal begins by providing, at step  602 , a first component having a microphone and a second component having an acoustic transducer. In the exemplary embodiment described above, the phone base  104  corresponds to the first component and the flip part  102  corresponds to the second component. The processing continues by placing, at step  604 , the second component into a second position with respect to the first component. In the above described exemplary embodiment, the open position of the cell phone  100  corresponds to this second position. The processing then passes, at step  606 , a sound pressure signal generated by the acoustic transducer  406  through at least one acoustic port in a first wall of the second component. In the above described exemplary embodiment, this step passes the sound pressure signal through at least the outer side acoustic port  202 . The processing then places, at step  608 , the second component into a first position with respect to the first component. In the above described exemplary embodiment, the closed position corresponds to this first position. The processing then passes, at step  610 , an ambient sound pressure signal that enters the at least one acoustic port to the microphone protrusion  108  by passing the ambient sound pressure signal through at least one dual purpose acoustic port  112  on a second wall of the second component. 
     As is understood by those of ordinary skill in the relevant art, the operation of embodiments of the present invention are able to perform only a subset of the above described steps and are further able to perform these steps in a different order that described above. 
       FIG. 7  illustrates a block diagram of a cellular phone  700  incorporating an exemplary embodiment of the present invention. The cellular phone  700  includes an RF antenna  702 , an RF receiver  704  and an RF transmitter  706 . The RF transmitter  706  and RF receiver  704  are connected to the RF antenna  702  in order to support bi-directional RF communications. The cellular phone  700  is able to simultaneously transmit and receive voice and/or data signals. The RF receiver  704  provides voice data to an audio processor  708  and the audio processor  708  provides voice data to the RF transmitter  706  to implement voice communications. The audio processor  708  obtains voice signals from microphone cartridge  406  and generates audio signals that are provided to the acoustic transducer  402  or to the high output speaker  410 , dependent upon the operational mode of the cellular phone. The RF receiver  704 , RF transmitter  706 , audio processor  708 , microphone cartridge  406  and acoustic transducer  402  operate to communicate voice signals to and from the cellular phone  700 . 
     The cellular phone  700  includes a controller  716  that controls the operation of the cellular phone in the exemplary embodiment. Controller  716  is connected to the various components of the cellular phone  700  via control bus  722 . Controller  716  communicates data to external devices (not shown), such as a base station and/or a server, through a wireless link. Controller  716  provides data to and accepts data from data processor  714 . Data processor  714  of the exemplary embodiment performs communications processing necessary to implement over-the-air data communications to and from external devices. Data processor  714  provides data for transmission to the RF transmitter  706  and accepts received data from the RF receiver  704 . 
     Controller  716  provides visual display data to the user through display  110 . Display  110  of the exemplary embodiment is a Liquid Crystal Display that is able to display alphanumeric and graphical data. Controller  716  also accepts user input from keypad  106 . Keypad  106  is similar to a conventional cellular phone keypad and has buttons to accept user input in order to support operation of the cellular phone  700 . 
     The cellular phone  700  further includes non-volatile memory  726 . Non-volatile memory  726  stores program data and more persistent data for use by the controller  716 . Data stored in non-volatile memory  726  of the exemplary embodiment can be changed under control of controller  716  if called for by particular processing performed by the controller  716 . The cellular phone  700  further contains volatile memory  724 . Volatile memory  724  is able to store transient data for use by processing and/or calculations performed by the controller  716 . 
     The terms “a” or “an”, as used herein, are defined as one or more than one. The term plurality, as used herein, is defined as two or more than two. The term another, as used herein, is defined as at least a second or more. The terms including and/or having, as used herein, are defined as comprising (i.e., open language). The term coupled, as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically. 
     Although specific embodiments of the invention have been disclosed, those having ordinary skill in the art will understand that changes can be made to the specific embodiments without departing from the spirit and scope of the invention. The scope of the invention is not to be restricted, therefore, to the specific embodiments. Furthermore, it is intended that the appended claims cover any and all such applications, modifications, and embodiments within the scope of the present invention.