Abstract:
A headset is disclosed. The headset includes an earpiece, a voice conducting and connecting system and a microphone connected to the voice conducting and connecting system, the microphone being capable of operating in a directional configuration and in an omnidirectional configuration.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to the field of headsets, including those used with telephone communication. 
     BACKGROUND OF THE INVENTION 
     Headsets of various types are commonly used for telephone or radio communication. With reference to  FIG. 1  a conventional headset system  10  shown, including a headband  12  on which is mounted a speaker assembly  14  located near the user&#39;s ear. A boom  16  is connected to the speaker assembly  14  to carry sound from the user&#39;s mouth to a microphone, not shown, which is located near the speaker assembly  14 . An alternative form of a conventional headset is shown in  FIG. 2 , which includes an over the ear connector  20  which enables the user to mount the connector  20  to the ear. Both types of headsets can send and receive signals using wires connected to a source such as a telephone, or they can send and receive signals without wires via a small radio receiver/transmitter. 
     Contemporary headset design demands that a headset be compact and discreet. In a headset, the spacing between the end of the boom and the user&#39;s mouth influences the quality of the audio signal received by the microphone and therefore the quality of the signal transduced by the microphone and the electronic signal transmitted by the microphone. Normally, if the end of the boom is closer to the user&#39;s mouth a higher quality signal can be produced by the microphone than if the end of the boom is far away. Also, a noisy environment can adversely affect the ability of the microphone to transduce and transmit an accurate rendition of the voice of the user. Therefore, to communicate well in the presence of background noise the distal end of the boom must be located relatively near the user&#39;s mouth, which can result in the boom being long so that the style is not ideal. 
     Accordingly, it is desirable to have a headset with improved noise cancelling abilities and which meets today&#39;s aesthetic design requirements. 
     BRIEF SUMMARY OF THE INVENTION 
     An embodiment of the present headset includes an earpiece, a voice conducting and connecting system, and a microphone. The microphone is capable of operating in a directional configuration and in an omnidirectional configuration, and a conversion system is provided to permit a user to selectively convert the microphone between the directional configuration and the omnidirectional configuration. The voice conducting and connection system can include a voice tube and a boom, and the user can locate the voice tube in a retracted, discreet position or in an extended, high performance position. 
     Further features and advantages of the present invention, as well as the structure and operation of the above-summarized and other exemplary embodiments of the invention, are described in detail below with respect to accompanying drawings, in which like reference numbers are used to indicate identical or functionally similar elements. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a conventional headset; 
         FIG. 2  illustrates a conventional ear-mounted headset; 
         FIG. 3  is a schematic illustration showing in partial cross-section an embodiment of the present headset in the retracted, discreet, position; 
         FIG. 4  is a schematic, cross-sectional illustration of a portion of the embodiment shown in  FIG. 3 ; 
         FIG. 5  is a schematic, cross-sectional illustration of the embodiment of the headset of  FIG. 3 , shown in the open, extended, position; 
         FIG. 6  is a schematic, cross-sectional illustration showing an alternative embodiment of the present headset in the retracted, discreet, position; and 
         FIG. 7  is a schematic, cross-sectional illustration of the alternative embodiment of the headset of  FIG. 6 , shown in the open, extended, position 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the present invention are described herein. Those of ordinary skill in the art will realize that the following detailed description of the present invention is illustrative only and is not intended to be in any way limiting. Other embodiments of the present invention will readily suggest themselves to such skilled persons having the benefit of this disclosure. Reference will now be made in detail to implementations of the present invention as illustrated in the accompanying drawings. The same reference indicators will be used throughout the drawings and the following detailed description to refer to the same or like parts. 
     In the interest of clarity, not all of the routine features of the implementations described herein are shown and described. It will, of course, be appreciated that in the development of any such actual implementation, numerous implementation-specific decisions must be made in order to achieve the developer&#39;s specific goals, such as compliance with application- and business-related constraints, and that these specific goals will vary from one implementation to another and from one developer to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of engineering for those of ordinary skill in the art having the benefit of this disclosure. 
     With reference to  FIGS. 3-5  an embodiment of the present headset is shown in partial cross-sectional, schematic form. The headset includes an earpiece  22  which contains a speaker, not shown, and a resilient member  24  which is designed to engage the user&#39;s ear. It should be understood that the earpiece  22  also includes an ear engagement member, not shown, which can be hooked over the user&#39;s ear so the device can be carried by the user without the use of the hands. The earpiece  22  also includes a curved, cylindrical member  26  which is connected to an internal shaft  30 , and the distal end of the curved, cylindrical member  26  is connected to a boom  31 . 
     The boom  31  includes an external housing  32  which is substantially cylindrical, and the external housing  32  includes an internal flange  34  near the proximal end and an opening  36  at the distal end thereof. Also, at the distal end of the external housing  32  the housing includes a hinge  40  on which is mounted a voice tube  50  and a cam  52 . The voice tube  50  is a cylinder having a bore  51 . The voice tube  50  has an arcuate configuration and the proximal end is connected to the cam  52 . The cam  52  and the hinge  40  are connected together by pin  54  so that the cam and voice tube  50  can rotate with respect to the external housing  32 . 
     The boom  31  also includes a microphone module  60  which is located inside the distal end of the external housing  32 . The microphone module  60  is substantially cylindrical and hollow and has closed ends, and the microphone module  60  fits in slideable engagement within the central bore of the external housing  32 . A microphone boot  61  is mounted inside the distal end of the microphone module  60 , and a noise canceling microphone  62  of conventional design is mounted inside the microphone boot  61 . 
     The noise canceling microphone  62  includes a diaphragm  63  with a main port  70  located to one side of the diaphragm  63  and a cancellation port  76  located to the opposite side of the diaphragm  63 . A first opening  70   a  is formed in the boot  61  adjacent the main port  70 , and a second port  76   a  is formed in the boot  61  adjacent the cancellation port  76 . A primary tube  72  is located between the first opening  70   a  and a primary port  74  formed in the distal end of the microphone module  60 . A second tube  78  is located between the second opening  76   a  and a secondary port  79  formed in the side of the microphone module  60 . It should be understood that for clarity electrical wiring of the microphone  60  is not shown in the drawings. One design of a conventional noise canceling microphone which can be used with the present embodiment is commonly used in hearing aids in which the noise canceling microphone amplifies sounds coming from the direction in which the user is facing while suppressing other sounds. One such hearing aid is taught in U.S. Pat. No. 3,876,843 titled “Directional Hearing Aid with Variable Directivity.” 
     A helical spring  80  is located around the internal shaft  30  and between the internal flange  34  and the proximal end of the microphone module  62  to bias the internal flange  34  and the proximal end of the microphone module  62  away from each other. 
     It should be appreciated that a number of electronic components of the device have been omitted from the drawings for the purpose of clarity. For example, a radio transmitter/receiver, not shown, is located inside the earpiece, and wiring, not shown, connects the microphone  62  to the transmitter/receiver. The transmitter/receiver can be designed to communicate with a conventional Bluetooth device, for example. 
     The operation of the device can now be understood. In  FIG. 3  the headset is shown in a discreet (retracted) mode in which the voice tube  50  is oriented so that the distal end of the voice tube  50  is located near the external housing  32 . In this mode when the device is turned off the user can carry the device in a shirt pocket, for example, and the voice tube  50  can conveniently function as a clip to help hold the device in the user&#39;s pocket. 
     When the user wishes to operate the headset in the discreet mode the user hooks the device over his/her ear with an over the ear connector, not shown, so that the resilient member  24  is adjacent the user&#39;s ear and the primary port  74  points toward the user&#39;s mouth. In this mode the spring  80  biases the microphone module in the distal direction, and the distal end of the microphone module  60  abuts the cam  52 . The distal end of the microphone module  60  protrudes from the distal end of the external housing  32  so that the secondary port  79  is exposed to the atmosphere. Accordingly, the secondary port  79  and the cancellation port  76  of the microphone  62  receive sonic vibrations from the atmosphere. Therefore the noise cancellation microphone  62  operates in a directional mode with the preferred direction located toward the user&#39;s mouth. Thus the directional microphone operates to suppress ambient noise and helps to enhance the microphone&#39;s ability to respond to the user&#39;s voice. 
     In some circumstances the user may wish to use the headset in a high performance (extended) mode instead of the discreet mode shown in  FIG. 3 . In this case the user rotates the cam  52  and voice tube  50  about the hinge  40  so that the device is in the high performance position as shown in  FIG. 5 . In this configuration the distal end of the voice tube  50  is located near the user&#39;s mouth, and the proximal end of the voice tube  50  abuts the distal end of the microphone module  60 . Also, the proximal end of the bore  51  of the voice tube  50  is aligned with the primary port  74  so that the bore conveys the user&#39;s voice from the user&#39;s mouth to the main port  70  of the noise canceling microphone  62 . It should be noted that the cam  52  has forced the microphone module in the proximal direction and into the external housing  32  so that the secondary port  79  is located within the external housing  32 . In this orientation the external housing  32  forms a good acoustic seal with the secondary port  79  so that the ambient noise reaching the cancellation port  76  is minimized. Thus the noise cancellation feature of the microphone  62  has essentially been disabled and the microphone  62  now functions essentially as an omnidirectional microphone. 
     It should be understood that the profile of the cam  52  is such that during the first part of the pivoting motion the spring  80  forces the voice tube  50  toward the retracted position shown in  FIG. 3 , while in the second part of the pivoting motion the spring forces the voice tube toward the open position shown in  FIG. 5 . In other words, when the device is held horizontally with the earpiece  22  on the right and voice tube  50  at the bottom, to open the voice tube  50  from the closed position (the 3 o&#39;clock position) to about the 6 o&#39;clock position the user must apply force against the spring, and thereafter the spring  80  causes the voice tube to snap to the fully open (9 o&#39;clock) position. Once the device is in the open position the spring  80  acts to keep the second port  74  acoustically sealed against the distal end of the voice tube  50 , and the spring  80  also acts to keep the voice tube in the open position. 
     It should also be understood that as the voice tube is moved from the closed position ( FIG. 3 ) to the open position ( FIG. 5 ) the internal shaft  30  pushes the curved cylindrical member  26  in the proximal direction relative to the external housing  32 . Thus the external housing  32  is moved in the distal direction while the microphone module  62  does not move relative to the earpiece  22 . 
     Optionally, a switch  90  can be located in the external housing  32  to sense the position of the microphone module  60  relative to the housing  32 . The switch  90  would send signals to a control circuit  92  which would perform one or more of the following functions:
         1. To change the microphone gain, so that the transmit sensitivity relative to the user&#39;s voice remains nearly constant whether the voice tube  50  is in the open or closed position.   2. To engage a frequency equalization circuit so that the frequency response remains nearly constant whether the voice tube  50  is in the open or closed position.   3. To enable or disable noise reduction, to change expansion depth, or other processes that may have unwanted artifacts. A typical example of such a process is voice switching gated by the received signal, which may be necessary for echo control in the discreet mode only.       

     Turning now to  FIGS. 6-7  an alternative embodiment is shown. In this embodiment many of the components are the same as in the embodiment shown in  FIGS. 3-5  and discussed above. However, unlike the  FIGS. 3-5  embodiment the embodiment of  FIGS. 6-7  includes a bored cam member  94 , which includes bore  96 . In the closed position ( FIG. 6 ) the bore  96  aligns with the second port  74  to essentially form an extension of the second tube  72  toward the user&#39;s mouth. Thus by selecting an appropriate diameter of the cam  94  the effective length of the second tube  72  can be extended while the voice tube  50  is in the closed position. 
     Although the present invention has been described with reference to specific embodiments thereof, these embodiments are merely illustrative, and not restrictive of, the present invention. Various modifications or changes to the specifically disclosed exemplary embodiments will be suggested to persons skilled in the art. Accordingly, the scope of the invention should not be restricted to the specific exemplary embodiments disclosed herein, and all modifications that are readily suggested to those of ordinary skill in the art should be included within the spirit and purview of this application and scope of the appended claims.