Abstract:
A personal sound amplifier device in the form of a hearing aid worn by a user not only amplifies sounds but also communicates wirelessly with an external electronic device, such as a cellular telephone. The personal sound amplifier device includes a first microphone, an amplification circuit electrically connected to the first microphone, and a speaker electrically connected to the amplification circuit for amplifying ambient sound detected by the first microphone. A second microphone is situated away from the first microphone. A radio frequency (RF) transmitter and receiver circuit is electrically connected to the second microphone and to the speaker. An antenna is connected to the RF transmitter and receiver circuit. The user&#39;s voice is detected by the second microphone and transmitted by the RF transmitter and receiver circuit, through the antenna, to an external electronic device. Signals from the external electronic device are received by the antenna and processed by the RF transmitter and receiver circuit, and are emitted as sound through the speaker for the user to hear.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is related to U.S. Provisional Application Ser. No. 61/584,402, filed on Jan. 9, 2012, and entitled “Personal Sound Amplifier”, the disclosure of which is incorporated herein by reference and on which priority is hereby claimed. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to personal sound amplification devices for use by hearing impaired persons, and more particularly relates to personal sound amplification devices having Bluetooth™ functionality. 
         [0004]    2. Description of the Prior Art 
         [0005]    Conventional personal sound amplifiers (“PSAs”), including hearing aids, do not have integrated Bluetooth™ radios. The integration of Bluetooth™ radios into PSAs has been problematic due to battery power consumption, output sound interference, and the space required to incorporate a Bluetooth™ circuit within a hearing aid housing also having the PSA circuit. To utilize Bluetooth™ technology, conventional PSA designs resort to utilizing a pendant unit worn by the user as a frequency convertor between the PSA device and Bluetooth™ quipped electronic devices, such as smart phones, the Apple iPad™/iPhone™ devices, and Blackberry™ devices. The pendant unit converts the 2.4 GHz Bluetooth™ frequency into lower frequencies to avoid interference with the integrated circuitry within the PSA (hearing aid), and consumes less battery power. This pendant unit provides the additional internal space needed for housing a relatively large battery to power the frequency convertor circuitry, and a relatively large antenna. However, to utilize the Bluetooth™ capabilities, consumers must inconveniently wear the pendant unit along with the PSA. Conventional pendant units have significantly limited transmission ranges and signal loss problems. Accordingly, the user must wear this separate pendant unit having a larger battery and a larger antenna. 
       OBJECTS AND SUMMARY OF THE INVENTION 
       [0006]    It is an object of the present invention to provide a personal sound amplifier having an integrated Bluetooth™ circuit. 
         [0007]    It is another object of the present invention to provide a personal sound amplifier in the form of a hearing aid which includes a hearing aid amplification circuit and a short range radio frequency (RF) transmitter and receiver circuit to allow wireless communications between the hearing aid and an external electronic device, such as a cellular telephone. 
         [0008]    It is still another object of the present invention to provide a personal sound amplifier device, in the form of a hearing aid, which includes an amplifier circuit for amplifying ambient noise, and a wireless communication circuit for wirelessly communicating with an external electronic device, such as a cellular telephone, and which allows the user of the personal sound amplifier device to selectively permit operation of just the amplifier circuit, or allow operation of both the amplifier circuit and the wireless communication circuit. 
         [0009]    It a further object of the present invention to provide a personal sound amplifier which is small in size and convenient to use and which includes the capability of wirelessly communicating with a remote, external electronic device. 
         [0010]    It is yet a further object of the present invention to provide a hearing aid having Bluetooth™ functionality and which requires no separate pendant unit to effect wireless communication with an external, remote electronic device, such as a cellular telephone. 
         [0011]    It is another object of the present invention to provide a personal sound amplifier which overcomes the inherent disadvantages of conventional personal sound amplifiers. 
         [0012]    The present invention provides a novel PSA that includes an embedded low power Bluetooth™ radio that overcomes the disadvantages found in conventional PSA designs. In accordance with one form of the present invention, a personal sound amplifier is preferably formed in the shape of, and functions as, a hearing aid worn by a user on or in his ear. The personal sound amplifier includes an ambient sound amplification circuit, a first microphone electrically connected to the ambient sound amplification circuit, and a speaker or transducer. The first microphone detects ambient sounds, and provides an output signal corresponding to the ambient sounds detected by the first microphone to the ambient sound amplification circuit. The ambient sound amplification circuit effectively amplifies the sounds detected by the first microphone, and provides an output signal corresponding to the amplified ambient sounds to the speaker or transducer, which amplified sounds may be heard by the user of the personal sound amplifier. 
         [0013]    The personal sound amplifier also includes a short range, radio frequency (RF) transmitter and receiver circuit, such as a Bluetooth™ circuit, to allow wireless communications between the personal sound amplifier and an external electronic device, such as a cellular telephone. The RF transmitter and receiver circuit is electrically connected to a second microphone and to the speaker or transducer of the sound amplification circuit. The second microphone detects sounds when the user speaks, and provides an output signal corresponding thereto to the RF transmitter and receiver circuit. The RF transmitter and receiver circuit transmits a corresponding signal wirelessly to an external electronic device situated remotely from the personal sound amplifier. An antenna connected to the output of the RF transmitter and receiver circuit is used to transmit signals from the personal sound amplifier to the external electronic device, and to receive signals transmitted by the external electronic device to the personal sound amplifier. 
         [0014]    More specifically, the signals which are transmitted by the external electronic device are received by the antenna of the personal sound amplifier. The antenna provides such received signals to the RF transmitter and receiver circuit, which converts such signals to audible frequency signals and amplifies the audible frequency signals (or uses the amplification circuit for amplifying these signals), and provides the amplified audible frequency signals to the speaker or transducer of the personal sound amplifier. 
         [0015]    The user of the personal sound amplifier may communicate wirelessly with an external electronic device, such as a cellular telephone, situated remotely from the personal sound amplifier, as well as selectively hearing amplified ambient sounds. The user may disable the RF transmitter and receiver circuit so that only the amplification circuit for amplifying ambient sounds is operational, or the user may enable both the ambient sound amplification circuit and the RF transmitter and receiver circuit so that he may both hear ambient sounds, amplified, and wirelessly communicate with an external electronic device, such as a cellular telephone. 
         [0016]    These and other objects, features and advantages of the present invention will be apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a perspective view of a personal sound amplifier formed in accordance with the present invention showing a charging cable connected to the personal sound amplifier, the personal sound amplifier being in the form of a hearing aid. 
           [0018]      FIG. 2  is a partially exploded, perspective view of the personal sound amplifier formed in accordance with the present invention showing the internal circuitry contained within an internal cavity of the main body thereof. 
           [0019]      FIG. 3  is a schematic diagram of the electronic circuit of the personal sound amplifier formed in accordance with the present invention. 
           [0020]      FIG. 4  is a block diagram of the electronic circuit of the personal sound amplifier formed in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    As can be seen in  FIG. 1  of the drawings, a personal sound amplifier  2  constructed in accordance with a preferred embodiment of the present invention includes a main body or housing  4  formed in the shape of a hearing aid (i.e., with a generally arcuate shape) and ergonomically shaped to rest on the ear of a user. The housing or main body  4  is formed from two matable half sections. When mated together, the two sections define an internal cavity for housing the electronic circuit, antenna and battery of the personal sound amplifier  2 . The main body  4  has mounted thereon a pair of microphones oriented at opposite lateral ends thereof, a mode selection switch  6 , a Bluetooth™ circuit activator switch  8 , a micro-USB connector  11  used in conjunction with a battery charging circuit for charging the internal battery, and a hollow hearing tube  12  extending from the main body  4 . As will be described in greater detail, the electronic circuit situated in the internal cavity of the main body  4  includes a Bluetooth™ circuit  28  and a personal sound amplification circuit  30 . 
         [0022]    More specifically, and referring to  FIG. 2  of the drawings, it will be seen that the main body  4  comprises a first half section  14  and a second half section  16 . When joined, the first half section  14  and the second half section  16  define an internal cavity  18  in which the circuitry and electronics of the personal sound amplifier  2  are secured. A first microphone  20  in electrical communication with the Bluetooth™ circuitry  28  extends at least partially through a first lateral end or side wall  24  of the main body  4 . A second microphone  22  in electrical communication with the conventional personal sound amplification circuitry  30  extends at least partially through a second lateral end or side wall  26  of the main body  4 , the second lateral end or side wall  26  being oriented opposite to the first lateral end or side wall  24 . As will be described in greater detail, the first microphone  20  is utilized by the Bluetooth™ circuitry  28  to receive audible sounds from the user. The second microphone  22  is utilized by the conventional personal sound amplification circuitry  30  to receive ambient audible sounds and amplify them for the user. The microphones  20 ,  22  are positioned at opposite ends or side walls of the main body  4  to reduce feedback interference between the Bluetooth™ circuitry  28  and the conventional amplification circuitry  30 . 
         [0023]    Referring again to  FIG. 1  of the drawings, it will be seen that a mode selection switch  6  in electrical communication with the Bluetooth™ circuitry  28  and conventional amplification circuitry  30  extends at least partially through a top portion  32  of the main body  4 . The mode selection switch  6  allows the user to selectively control the operation of the personal sound amplifier device  2  of the present invention. When the mode selection switch  6  is in a first position, also referred to as the “up” position, the personal sound amplifier device  2  operates in a first mode in which the Bluetooth™ functionality and circuitry  28  are enabled and the conventional amplification (hearing aid) circuitry  30  is disabled. When the switch  6  is in a second position, also referred to as the “down” position, the device operates in a second mode in which both the Bluetooth™ functionality and circuitry  28  and the conventional amplification (hearing aid) circuitry  30  operate concurrently. 
         [0024]    A Bluetooth™ circuit activator switch  8  in electrical communication with the Bluetooth™ circuitry  28  extends outwardly from the second half  16  of the main body  4 . The activator switch  8  is preferably a momentary push button switch that controls the power to the Bluetooth™ circuitry  28  and the pairing of the Bluetooth™ circuitry  28  with an external Bluetooth™ capable device (not shown), as will be described in greater detail in the forthcoming paragraphs. 
         [0025]    Referring to  FIGS. 1 and 2  of the drawings, it will be seen that the battery charging circuit  10  includes a micro-USB female connector  11  which is mounted on the first lateral end  24  of the main body  4  and is provided to accept a male micro-USB connector  34  as a DC input. As will be described in greater detail, the female connector  11  is in electrical communication via internal circuitry with a lithium polymer battery  36  contained within the cavity  18  of the main body  4  that provides power to the Bluetooth™ circuitry  28  and conventional amplification circuitry  30  for the hearing aid function. 
         [0026]    Referring to  FIGS. 2 and 3  of the drawings, it will be seen that the conventional amplification circuitry&#39;s speaker output pins  40  and the Bluetooth™ circuitry&#39;s speaker output pins  42  are connected to a miniature internal speaker  38  positioned within the cavity  18 . An outlet adapter  44 , preferably being constructed of brass, is connected to the miniature speaker  38  and extends at least partially through the second end  26  of the main body  4 . The hearing tube  12  further includes a first axial end  13 . The first end  13  is fitted on the speaker outlet adapter  44 . A dome or ear bud  48  is mounted on the length of the hollow hearing tube  12  and is placed in the ear canal of the user, and emits therefrom the sound carried by the hearing tube  12  from the speaker  38 . The opposite end portion  15  of the tube  12  acts as a retention end and may be shaped to conform to the shape of the user&#39;s ear to help retain the ear bud or dome  48  within the ear canal. 
         [0027]    Again referring to  FIG. 2  of the drawings, it is seen that the personal sound amplifier  2  formed in accordance with a preferred embodiment of the present invention includes conventional amplification circuitry  30  and Bluetooth™ circuitry  28  within the internal cavity  18  of the main body  4 . Referring to  FIGS. 3 and 4  of the drawings, it can be seen that the conventional amplification circuitry  30  preferably comprises an integrated circuit  50  manufactured by Intricon Corporation, specifically, the Intricon Hybrid IC for PSA, Part No. DS — 91969 — 009, which includes integrated digital signal processing, a microphone input, and an audio amplifier on a flexible printed circuit board. The Intricon integrated circuit  50  is powered by a 3.3 volt (V) lithium polymer battery  36 , which voltage is reduced from 3.3V to about 1.5V via a 470 ohm resistor  52  and two series-connected 1N4148 diodes  54 . The mode selection switch  6  is connected in series between the lithium polymer battery  36  and the Intricon integrated circuit  50  so that, when the first mode (Bluetooth™ function only) is selected, the power to the Intricon integrated circuit  50  is cutoff and the conventional amplification circuitry  30  (for the hearing aid function) is disabled. When the second mode (both Bluetooth™ and hearing aid functions) is selected, the Intricon integrated circuit  50  is operational and receives audible sounds from the environment surrounding the user via the second microphone  22  connected to the microphone inputs  56  thereof The received sounds are input to the integrated circuit&#39;s internal amplifier and output to the miniature speaker  38  contained within the housing cavity  18 . The Intricon integrated circuit  50  may further be connected to an audio level adjustor  58 , preferably in the form of a momentary push button switch, extending at least partially from the top portion  32  of the main body  4 . The audio level adjustor  58 , when activated, selectively adjusts the audio output decibel and frequency pass band of the integrated circuit  50  based upon three or four pre-programmed levels. 
         [0028]    Again referring to  FIGS. 3 and 4  of the drawings, it will be seen that the Bluetooth™ circuitry  28  within the cavity  18  of the main body  4  preferably includes a Bluetooth™ integrated circuit  60  manufactured by ISSC Technologies that comprises a Bluetooth 3.0 radio module with mono and/or stereo outputs, having Part No. IS1632N, mounted on a printed circuit board, and a microphone input  62 . The Bluetooth™ integrated circuit  60  is powered by the lithium polymer battery  36 . The Bluetooth™ circuit further includes a microstrip antenna  64  situated on the printed circuit board and oriented vertically (when the personal sound amplifier is properly worn by a user) for Bluetooth™ 2.4 GHz communication. The orientation and proximity of the microstrip antenna  64  to the user&#39;s body on the printed circuit board and within the main body  4  of the device  2  allows the user&#39;s body to enhance the microstrip antenna&#39;s reception/transmission and further reduces signal loss between the Bluetooth™ devices and the personal sound amplifier  2  so that the transmitting range can still meet the normal Bluetooth™ Class 2 radio standard of 30 feet. The first microphone  20  in electrical communication with the Bluetooth™ integrated circuit  60  receives the user&#39;s audible sounds. The audible sounds are then encoded by the integrated circuit&#39;s internal signal processor and are sent wirelessly to an external Bluetooth™-capable device, such as an iPhone™ device or Blackberry™ device, via the microstrip antenna  64 . The microstrip antenna  64  also receives wireless transmissions from the external device and inputs them to the Bluetooth™ integrated circuit  60 . The speaker outputs  66  of the Bluetooth™ integrated circuit  60  are connected to the internal miniature speaker  38 . Transmissions received by the microstrip antenna  64  are processed by the integrated circuit  60  and then output to the user through the miniature speaker  38 . 
         [0029]    An LED (light emitting diode) Bluetooth™ status indicator  68  extending at least partially through the second half  16  of the main body  4 , or at least visually identifiable within the second half  16  of the main body  4 , is connected to the Bluetooth™ integrated circuit  60  and assists with the control of the device&#39;s Bluetooth™ functionality. More specifically, a user may selectively activate the Bluetooth™ function via activator switch  8  extending through the second half  16  of the main body  4  in response to the LED Bluetooth™ status indicator&#39;s output. For example, to establish communication between the external Bluetooth™-capable device and the personal sound amplifier  2  formed in accordance with the present invention, it is necessary to “pair” the devices. To pair the devices, it is first necessary to turn the Bluetooth™ function on by pressing the Bluetooth™ activator switch  8  once. Once the Bluetooth™ function has been turned on, the LED Bluetooth™ status indicator  68  will flash every two seconds to indicate that the Bluetooth™ functionality has been activated. To pair the personal sound amplifier  2  and the external Bluetooth™-capable device for the first time, the activator switch  8  is depressed for a few seconds and the LED indicator  68  will flash and then change to a steady illumination state, indicating that the personal sound amplifier&#39;s Bluetooth™ functionality is ready for pairing (i.e., the personal sound amplifier  2  may be recognized by the external Bluetooth™-capable device). The external device then searches for the Bluetooth™ signal transmitted by the personal sound amplifier  2 , and a numeric pairing key corresponding to the Bluetooth™ integrated circuit, typically “0000”, is entered to pair the devices. After the first pairing has been completed, the external device will recognize the personal sound amplifier for subsequent pairings automatically. To turn off the Bluetooth™ functionality, a user may press and hold the Bluetooth activator switch  8  for a few seconds, and the LED status indicator  68  will go off, indicating that the Bluetooth™ functionality has been turned off. 
         [0030]    Referring again to  FIGS. 3 and 4  of the drawings, it will be seen that the battery charging circuit  10  preferably includes a micro-USB female connector  11  (or some other form of adapter) in which a 5V DC source is input to a power supply or voltage regulator or converter circuit  70  defining at least a portion of the battery charging circuit  10 . As shown in greater detail in the schematic illustrated in  FIG. 3  of the drawings, the charging circuit  10  charges a 3.3V lithium polymer battery  36  that is positioned within the cavity  18  of the main body  4  of the personal sound amplifier  2  and provides power to both the Bluetooth™ circuitry  28  and the conventional amplifier circuitry  30  for the hearing aid function. 
         [0031]    In operation, when the user desires to use the personal sound amplifier&#39;s Bluetooth™ functionality to communicate with his external Bluetooth™-capable cellular phone or other device, the user would place the mode selection switch  6  in the first position. In this position, the conventional amplifier circuitry  30  is disabled and the Bluetooth™ circuitry  28  is enabled. The user&#39;s audible transmissions are received by the first microphone  20  in electrical communication with the Bluetooth™ integrated circuit  60  and wirelessly transmitted to the paired external cellular phone. Incoming telecommunication transmissions received by the external cellular phone from a telecommunications network are then wirelessly transmitted back to the personal sound amplifier&#39;s Bluetooth™ integrated circuit  60  and output to the user from the miniature speaker  38  and hearing tube  12  connected thereto. 
         [0032]    When the user desires to have both Bluetooth™ functionality and conventional amplifier functionality operating, for example, while driving a car in which it is necessary both to hear the ambient sounds of the road and communicate with an external cellular phone, the user may place the mode selection switch  6  in the second position. In this position, the lithium polymer battery  36  provides power to both the Bluetooth™ circuitry  28  and the conventional amplification circuitry  30 . As discussed in the previous paragraph, the first microphone  20  will receive audible transmissions from the user and transmit them to the external cellular phone via the personal sound amplifier&#39;s Bluetooth™ integrated circuit  60 . Simultaneously, the second microphone  22  in electrical communication with the conventional amplification circuitry  30  will receive ambient sounds from the environment, amplify them via the Intricon integrated circuit  50 , and output them to the user through the miniature speaker  38  and hearing tube  12  connected thereto. As can be seen in the block diagram illustrated in  FIG. 4  of the drawings, both the Bluetooth™ integrated circuit  60  and Intricon integrated circuit  50  output their signals to the same miniature speaker  38 . Thus, the user may hear both amplified ambient sounds and wireless transmissions from an external device simultaneously from a single speaker  38 . Furthermore, by using two separate microphones  20 ,  22  which are located on the main body  4  in opposite directions from each other, this arrangement reduces or avoids feedback interference from the ambient sounds detected by microphone  22  of the hearing aid circuit and the user&#39;s voice detected by the microphone  20  of the Bluetooth™ circuit. Accordingly, the user may be able talk on the phone via Bluetooth™ transmission and also be alert to surrounding ambient noise. 
         [0033]    Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention.