Patent Publication Number: US-8976957-B2

Title: Headset microphone boom assembly

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of application No. 61/823,707, filed on May 15, 2013, which is fully incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Arrangements described herein relate to headsets and, more particularly, to headset microphone booms. 
     A headset typically includes one or two speakers mounted in a housing to be positioned adjacent a user&#39;s ear, or ears, and one or more microphones to detect spoken utterances produced by the user and optionally background noise. Some headsets are configured to communicate with audio devices or systems, such as mobile phones or computers, via wired connections. In other arrangements, headsets may be configured to communicate with such audio devices or systems via a wireless link, such as a Bluetooth® radio frequency link. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts a headset, which is useful for understanding various arrangements described herein. 
         FIG. 2  depicts an enlarged exploded view of a microphone boom of the headset of  FIG. 1 , which is useful for understanding various arrangements described herein. 
         FIG. 3  depicts an enlarged section view of a distal portion of the microphone boom of the headset of  FIG. 1 , taken along section line  3 - 3 , in accordance with one arrangement described herein. 
         FIG. 4  depicts an enlarged section view of a distal portion of the microphone boom of the headset of  FIG. 1 , taken along section line  3 - 3 , in accordance with another arrangement described herein. 
         FIG. 5  depicts an enlarged section view of a near portion of the microphone boom of the headset of  FIG. 1 , taken along section line  3 - 3 , which is useful for understanding various arrangements described herein. 
         FIG. 6  is a flowchart presenting a method of assembling a boom, which is useful for understanding various arrangements described herein. 
     
    
    
     DETAILED DESCRIPTION 
     While the specification concludes with claims defining features of the embodiments described herein that are regarded as novel, it is believed that these embodiments will be better understood from a consideration of the description in conjunction with the drawings. As required, detailed arrangements of the present embodiments are disclosed herein; however, it is to be understood that the disclosed arrangements are merely exemplary of the embodiments, 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 embodiments 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 present arrangements. 
     It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numbers may be repeated among the figures to indicate corresponding or analogous features. 
       FIG. 1  depicts a headset  100 , which is useful for understanding various arrangements described herein. The headset can be configured to communicate with audio devices or systems via a wired connection, a wireless link such as a Bluetooth® radio frequency (RF) link, a personal area network, or via any other suitable communication medium. 
     The headset  100  can include at least one audio transducer, such as a speaker  105  configured to be placed proximate to a user&#39;s ear. Further, the headset  100  can include a microphone boom assembly (hereinafter “boom”)  110  comprising a boom housing  112  in which at least two microphone transducers (hereinafter “microphones”)  115 ,  120  are mounted in a microphone chamber  145  defined at a distal portion  150  of the boom  110 , the portion  150  being distal with respect to a body housing (e.g., a main housing)  170  of the headset  100 . The distal portion  150  of the boom  110  can be wider than a near portion  155  of the boom  110  in order to accommodate the microphones  115 ,  120  within the microphone chamber  145  of the boom housing  112 . 
     The first microphone  115  can be positioned proximate to a first aperture  135  defined in a first side  125  of the boom housing  112  where the microphone chamber  145  is located and the second microphone  120  can be positioned proximate to a second aperture  140  defined in a second side  130  of the boom housing  112  where the microphone chamber  145  is located. The second side  130  and the first side  125  can be on opposite sides of the chamber  145 . In illustration, at least a portion of the second side  130  can be generally parallel to at least a portion of the first side  125 . The first and second sides  125 ,  130  can be separated by a third side  160  and a fourth side  165 , which four sides together define the boom housing  112 , including the microphone chamber  145 . 
     Acoustic signals can propagate to the first microphone  115  through the first aperture  135 , and the first microphone  115  can be configured to detect such acoustic signals. Similarly, acoustic signals can propagate to the second microphone  120  through the second aperture  140 , and the second microphone  120  can be configured to detect such acoustic signals. Accordingly, the first microphone  115  can primarily detect spoken utterances and other sounds generated by a user wearing the headset  100 , and the second microphone  120  can detect background noise, which can be processed by a suitable processor or controller to implement noise cancelling functions. 
     The boom  110  can be substantially linear along the second side  130 , or the boom  110  can be curved to place the first aperture  135  closer to the user&#39;s face. For example, the side  130  can be convex. Further, the near portion  155  of the boom  110  can be configured to slidably engage the body housing  170  of the headset  100 . In this regard, the boom  110  can be selectively moved relative to the body housing  170  along an axis  175  between a retracted position and an extended position. In the retracted position, at least part of the near portion  155  of the boom  110  can retract into the body housing  170  of the headset  100 . In the extended position, at least part of the near portion  155  of the boom can extend away from the body housing  170  of the headset  100 . Thus, a user can slidably adjust the position of the boom  110  as desired. 
       FIG. 2  depicts an enlarged exploded view of the boom  110  of  FIG. 1 , which is useful for understanding various arrangements described herein. The boom  110  can include first structural member  202  defining the first side  125  and a second structural member  204  defining the second side  130 . Together, the structural members  202 ,  204  can define the boom housing  112 . The first structural member  202  can be made of metal, plastic or any other suitable material. The second structural member  204  also can be made of metal, plastic or any other suitable material. For example, the first structural member  202  can be made of injection molded plastic and the second structural member  204  can be made of injection molded metal. In one arrangement, the injection molded plastic can have a thickness of approximately 0.75 mm and the injection molded metal can have a thickness of approximately 0.6 mm, though the present arrangements are not limited in this regard. 
     The first aperture  135  can be defined in the first structural member  202  and the second aperture  140  can be defined in the second structural member  204 . The first structural member  202  and/or the second structural member  204  can be configured in shape to define the microphone chamber  145  at the distal portion  150  of the boom  110  where the microphones  115 ,  120  are positioned within the boom  110 . 
     The boom  110  further can include a flexible printed circuit (hereinafter “flex”)  210  mounted between the first and second structural members  202 ,  204 . The flex  210  can electrically connect the microphones  115 ,  120  to a suitable processor or controller of the headset  100  ( FIG. 1 ), for example a processor or controller within the body housing  170  of the headset  100 . The flex  210  can include a first side  214  and a second side  216 . In one arrangement, printed circuit traces can be disposed on and/or or beneath both sides  214 ,  216  of a flex body. The second side  216  can be generally parallel and opposite to the first side  214 . The flex  210  can be a flex strip having a body manufactured of at least one flexible dielectric substrate, such as a flexible polymer film, which in one arrangement, provides the thickness of the flex  210  (i.e., the distance between the sides  214 ,  216 ) to be approximately 0.15 mm, or thinner, though the present arrangements are not limited in this regard. In one arrangement, the flexible polymer film can be a polyamide film, which suitably withstands high temperatures applied during soldering processes used to connect components to the flex  210 . In another arrangement, the flex  210  could be a rigid-flex circuit strip having a body manufactured of one or more rigid substrates, for example polytetrafluoroethylene, and one or more flexible substrates which are laminated into a semi-rigid structure in which one or more bends may be formed. 
     The first microphone  115  can be connected (e.g., both electrically connected and physically attached) to the first side  214  of the flex  210  at a first location and the second microphone  120  can be connected (e.g., both electrically connected and physically attached) to the second side  216  of the flex  210  at a second location. For example, the microphones  115 ,  120  can be soldered to the flex  115 . In this regard, the first microphone  115  can be carried on the first side  214  of the flex  210  and the second microphone  120  can be carried on the second side  216  of the flex  210 , thus creating a microphone assembly which is carried in the boom  110 . Being flexible, the flex  210  can be bent to achieve a desired shape. For instance, the flex  210  can be mounted into the boom  110  with a bend  218  in the flex  210  positioned between the location where the first microphone  115  is connected to the flex  210  and the location where the second microphone  120  is connected to the flex  210 . The bend  218  can be generally S-shaped. 
     Accordingly, even though the microphones  115 ,  120  may be connected to the respective opposite sides  214 ,  216  of the flex  210 , and ported through opposite sides  125 ,  130  of the boom housing  112 , the distance between the sides  125 ,  130  of the boom  110  where the microphone chamber  145  is located can be the same as the distance would be if only one microphone were used. Moreover, rather than requiring the use both of a bottom ported microphone and a top ported microphone, both microphones  115 ,  120  can be bottom ported or both microphones  115 ,  120  can be top ported. The exclusive use of bottom ported microphones, or the exclusive use of top ported microphones, allows the same microphone type to be used for both the microphones  115 ,  120 . This can simplify tuning of audio signal processing algorithms used to implement noise cancelation, etc. The invention is not limited in this regard, however. For example, in other arrangements, the first microphone  115  can be bottom ported and the second microphone  120  can be top ported, or the first microphone  115  can be top ported and the second microphone  120  can be bottom ported. 
     A bottom ported microphone is a microphone configured to detect acoustic signals from a side of the microphone that connects the microphone to a printed circuit board. A top ported microphone is a microphone configured to detect acoustic signals from a side of the microphone opposite from the side that connects the microphone to a printed circuit board. Bottom ported microphones typically have a lower profile than top ported microphones. For example, one type of bottom ported microphone has a thickness of approximately 0.9 mm, while one type of top ported microphone has a thickness of approximately 1.1 mm. Nonetheless, microphones may be available with thinner profiles, and the present arrangements are not limited in this regard. 
     In the case that the microphones  115 ,  120  are bottom ported microphones, an aperture ( 302  of FIG.  3 —not shown in  FIG. 2 ) can be defined in the flex  210 , aligned with an acoustic port of the first microphone  115 , through which acoustic signals propagate to the first microphone  115 . Such aperture can align with at least a portion of the aperture  135 . Similarly, an aperture  220  can be defined in the flex  210 , aligned with an acoustic port of the second microphone  120 , through which acoustic signals propagate to the second microphone  120 . The aperture  220  can align with at least a portion of the aperture  140 . In the case that the microphones are top ported microphones, the apertures  302 ,  220  need not be defined in the flex  210 . 
     The boom  110  further can include a first boom mesh  230  configured to allow flow of acoustic signals through the mesh, while keeping dust out of the first microphone  115 . The first boom mesh  230  can be positioned between the first structural member  202  and a first adhesive  232 . The first adhesive  232  can be configured to adhere the side  216  of the flex  210 , at the location where the first microphone  115  is connected, to the first boom mesh  230 , and thus to the first structural member  202 . The first adhesive  232  can be positioned on the side  216  immediately opposite where the first microphone  115  is connected to the flex  210  on the side  214 . An aperture  234  can be defined in the first adhesive  232  to allow passage of acoustic signals through the first adhesive  232  to the first microphone  115 . 
     The boom  110  further can include a second boom mesh  240  configured to allow flow of acoustic signals through the mesh, while keeping dust out of the second microphone  120 . The second boom mesh  240  can be positioned between the second structural member  204  and a second adhesive  242 . The second adhesive  242  can be configured to adhere the side  214  of the flex  210 , at the location where the second microphone  120  is connected, to the second boom mesh  240 , and thus to the second structural member  204 . An aperture  244  can be defined in the second adhesive  242  to allow passage of acoustic signals through the second adhesive  242  to the second microphone  120 . A third adhesive  250  can be provided to attach the second side  216  of the flex  210  to the first structural member  202 . Similarly, a fourth adhesive  252  can be provided to attach the first side  214  of the flex  210  to the second structural member  204 . 
     The flex  210  can be mounted into the boom  110  with a generally U-shaped bend  222 , allowing the flex  210  to bend around the first structural member  202  and connect to a connector in the body housing  170  of the headset  100  ( FIG. 1 ) that provides an electrical connection to the processor or controller. In illustration, an end portion  224  of the flex  210  can be configured to engage the connector. The U-shaped bend  222  allows boom  110  to be moved between the retracted position and the extended position while the flex  210  maintains connection to the connector, and thus the processor or controller. In this regard, the U-shaped bend  222  is not stationary on the flex  210 . As the boom  110  is extended or retracted, the flex  210  can adjust accordingly. 
     Various tabs (or ribs)  160 ,  162  can be defined on the first structural member  202  to guide positioning of the various components  115 ,  120 ,  210 ,  230 ,  232 ,  240 ,  242  within the microphone chamber  145 . Similarly, various tabs (or ribs)  164  can be defined on the first structural member  202  to guide positioning of the flex  210  in the near portion  155  of the boom  110 . 
     An aperture  260  can be defined in the first structural member  202  into which a magnet  272  may be inserted. The magnet  272  can provide a level of resistance between the boom  110  and the body housing  170  (shown in  FIG. 1 ) to hold the boom  110  into a desired position when the position of the boom  110  is adjusted with respect to the body housing  170 . The magnet  272  also can trigger a Hall effect sensor (not shown) to generate one or more signals processed by a processor (or controller) to determine the position of the boom  110  with respect to the body housing  170 . 
       FIG. 3  depicts an enlarged section view of the distal portion  150  of the boom  110  of  FIG. 1 , taken along section line  3 - 3 , in accordance with one arrangement described herein. As noted, the distal portion  150  is the portion of the boom  110  defining the microphone chamber  145 , and the various components  115 ,  120 ,  210 ,  230 ,  232 ,  240 ,  242  can be positioned within the microphone chamber  145  defined between the first structural member  202  and the second structural member  204 .  FIG. 3  further depicts the aperture  302  in the flex  210  not shown in  FIG. 2 . 
     In the arrangement depicted in  FIG. 3 , the microphones  115 ,  120  are bottom ported microphones. In illustration, an acoustic port  304  can be defined in the first microphone  115  to receive acoustic signals, and an acoustic port  306  can be defined in the second microphone  120  to receive acoustic signals. The aperture  302  in the flex  210  can be aligned with the acoustic port  304  of the first microphone  115 , and the aperture  244  defined in the flex  210  can be aligned with the acoustic port  306  of the second microphone  120 . 
     The flex  210  can be mounted into the boom  110  with a bend  218 , for example a generally S-shaped bend, formed in the flex  210  and positioned between the location where the first microphone  115  is connected to the flex  210  and the location where the second microphone  120  is connected to the flex  210 . A portion of the flex  210  where the first microphone  115  is connected to the flex  210  can be positioned between the first microphone  115  and the first structural member  202 , for example between the first microphone  115  and the first adhesive  232 . Similarly, a portion of the flex  210  where the second microphone  120  is connected to the flex  210  can be positioned between the second microphone  120  and the second structural member  204 , for example between the first microphone  115  and the second adhesive  242 . 
     In one arrangement, the thickness  300  of the distal portion  150  of the boom  110 , between the opposing sides  125 ,  130 , can be equal to or less than approximately 2.8 mm, which is less than one-half of the width of a conventional boom which uses two microphones ported through opposing sides of the boom. The present arrangements are not limited to the dimension, however. 
       FIG. 4  depicts an enlarged section view of the distal portion  150  of the boom  110  of  FIG. 1 , taken along section line  3 - 3 , in accordance with another arrangement described herein. As noted, the distal portion  150  is the portion of the boom  110  defining the microphone chamber  145 , and the various components  115 ,  120 ,  210 ,  230 ,  232 ,  240 ,  242  can be positioned within the microphone chamber  145  defined between the first structural member  202  and the second structural member  204 . 
     In the arrangement depicted in  FIG. 4 , the microphones  115 ,  120  are top ported microphones. Since the microphones  115 ,  120  are top ported, apertures need not be defined in the flex  210  to pass acoustic signals to the microphones  115 ,  120 . Instead, an acoustic port  402  can be defined in a first side  404  of the first microphone  115  opposing a second side  406  of the first microphone  115  connecting the first microphone  115  to the flexible printed circuit board  210 . Similarly, an acoustic port  408  can be defined in a first side  410  of the second microphone  120  opposing a second side  412  of the second microphone  120  connecting the second microphone  120  to the flexible printed circuit board  210 , 
     Again, the flex  210  can be mounted into the boom  110  with a bend  420 , such as a generally S-shaped bend, formed in the flex  210  and positioned between the location where the first microphone  115  is connected to the flex  210  and the location where the second microphone  120  is connected to the flex  210 . In contrast to  FIG. 3 , a portion of the flex  210  where the first microphone  115  is connected to the flex  210  can be positioned between the first microphone  115  and the second structural member  204 , for example between the first microphone  115  and the second boom mesh  240 . Similarly, a portion of the flex  210  where the second microphone  120  is connected to the flex  210  can be positioned between the second microphone  120  and the first structural member  202 , for example between the first microphone  115  and the first boom mesh  230 . The flex  210  can be mounted into the boom  110  with another bend  404  following the contour of the first structural member  202 . 
     The first adhesive  232  can adhere the first microphone  115  to the first boom mesh  230 , and thus to the first structural member  202 . The second adhesive  242  can adhere the second microphone  120  to the second boom mesh  240 , and thus to the second structural member  204 . In one arrangement, the thickness  400  of the distal portion  150  of the boom  110 , between the opposing sides  125 ,  130 , can be equal to or less than approximately 3.0 mm. The present arrangements are not limited to this dimension, however. 
       FIG. 5  depicts an enlarged section view of the near portion  155  of the boom  110  of  FIG. 1 , taken along section line  3 - 3 , which is useful for understanding various arrangements described herein. In the near portion  155  of the boom, the flex  210  can be positioned between the first structural member  202  and the second structural member  204 . The flex  210  can be adhered to the first structural member using the third adhesive  250  and adhered to the second structural member using the fourth adhesive  252 . The thickness  500  of the near portion  155  of the boom  110 , between the sides  125 ,  130 , can be equal to or less than approximately 1.7 mm, though the present arrangements are not limited in this regard. 
     As noted, a magnet  272  can be positioned within the aperture  270 , and can trigger a Hall effect sensor (not shown) to allow the controller or processor to determine the position of the boom  110 . Specifically, as the magnet  272  moves past a portion  502  of the flex  210  external to the boom  110  when the boom  100  is moved relative to the body housing  170  of the headset  100  ( FIG. 1 ), the magnetic field generated by the magnet  272  can induce a signal on one or more circuit traces in the portion  502  of the flex  210 . This signal can be detected by the Hall effect sensor and processed to determine the position of the boom  110  with respect to the body housing  170  of the headset  100 . 
       FIG. 6  is a flowchart presenting a method  600  of assembling a boom, which is useful for understanding various arrangements described herein. At step  605 , a first microphone can be connected to a first side of a flexible printed circuit board at a first location. At step  610 , a second microphone can be connected to a second side of the flexible printed circuit board at a second location, the second side of the flexible printed circuit board generally parallel and opposite to the first side of the flexible printed circuit board. At step  615 , the flexible circuit board can be mounted into the microphone boom, wherein the first microphone is positioned proximate to a first aperture defined in a first side of the microphone boom through which acoustic signals propagate to the first microphone, the second microphone is positioned proximate to a second aperture defined in a second side of the microphone through which the acoustic signals propagate to the second microphone, and a bend is formed in the flexible printed circuit board, the generally bend positioned between the first location and the second location. 
     Like numbers have been used to refer to the same items throughout this specification. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The terms “a” and “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 term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will also be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms, as these terms are only used to distinguish one element from another unless stated otherwise or the context indicates otherwise. 
     Reference throughout this specification to “one arrangement,” “an arrangement,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one arrangement disclosed within this specification. Thus, appearances of the phrases “in one arrangement,” “in an arrangement,” and similar language throughout this specification may, but do not necessarily, all refer to the same arrangement. 
     The term “if” may be construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. Similarly, the phrase “if it is determined” or “if [a stated condition or event] is detected” may be construed to mean “upon determining” or “in response to determining” or “upon detecting [the stated condition or event]” or “in response to detecting [the stated condition or event],” depending on the context. 
     The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the embodiments disclosed within this specification have been presented for purposes of illustration and description, but are not intended to be exhaustive or limited to the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the embodiments of the invention. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the inventive arrangements for various embodiments with various modifications as are suited to the particular use contemplated. 
     These embodiments can be embodied in other forms without departing from the spirit or essential attributes thereof. Accordingly, reference should be made to the following claims, rather than to the foregoing specification, as indicating the scope of the embodiments.