Abstract:
A child monitor system that combines the functionality of a prenatal monitor and a conventional nursery room monitor in a single device. The device comprising a local unit and a remote unit. Each unit having the capability of receiving and outputting acoustic audio signals as well as the capability of transmitting and receiving these signals to and from the units. The device also comprises a selection device for allowing a user to select from a plurality of operating modes.

Description:
BACKGROUND  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to prenatal monitors and nursery room monitors and, more particularly, to a single device encompassing both.  
           [0003]    2. Discussion of the Related Art  
           [0004]    During the time period when expectant parents await their baby, much anticipation and excitement exists at the prospect of having a newborn. A large part of this excitement is the realization that the baby is living and growing inside the mother&#39;s womb. Consequently, expectant parents desire to hear evidence of their baby&#39;s existence, most notably the baby&#39;s beating heart and other movements. This greatly enhances the experience for the parents and allows them to feel closer to their child even before the mother gives birth. As a result, expectant parents may purchase devices that allow them to hear their unborn baby&#39;s heartbeat. These prenatal monitors, as they are called, also typically allow expectant parents to hear other sounds generated by the unborn child including kicks and hiccups. Some of these devices also allow expectant parents to record these sounds, play music or educational recordings to the child, and allow the parents to send the sound of the parents&#39; voices to the child. This is typically done using equipment external from the monitor itself. These devices, however, have a drawback in that their functional life is limited. Specifically, parents no longer have a need for these prenatal monitors when the mother gives birth. Thus, the parents set them aside after typically using them for only three months or less and possibly never use them again.  
           [0005]    After the birth of their child, parents often, however, need a room monitor. These devices allow parents to monitor the activities of their child from a remote location, usually from another room within the same home or from an area just outside of the home. The monitors, sometimes called baby monitors, infant monitors, or child monitors, usually have a transmitter and a receiver. The monitors transmit signals representing the activities within the monitored room to a receiver located in another room. Usually the monitors transmit activities of an audible nature such as a child&#39;s crying, breathing, or any other activities that generate audible signals. These devices, however, also have a drawback in that they are limited to this functionality. More particularly, parents cannot, for example, use them to monitor the heartbeat of an unborn child.  
           [0006]    Thus, it would be advantageous to have a device that incorporates the functions of a prenatal monitor and a room monitor into a single device thus extending the life of prenatal monitors and expanding the functionality of room monitors. Such a device will provide economic efficiency in that a consumer may purchase one product instead of two and use the product for an extended period of time.  
         SUMMARY OF THE INVENTION  
         [0007]    The disclosed child monitor overcomes the shortcomings of the prior art in that it allows a user to operate the system either as a nursery room monitor or as a prenatal monitor. The child monitor has two units, and the user may choose to use the system as a prenatal monitor, using one of the units, or as a conventional nursery room monitor using both the parent unit and the child unit. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    [0008]FIG. 1 is a schematic view of a first embodiment of a child monitor system.  
         [0009]    [0009]FIG. 2 illustrates a first operating mode of the child monitor system of FIG. 1.  
         [0010]    [0010]FIG. 3 illustrates a second operating mode of the child monitor system of FIG. 1.  
         [0011]    [0011]FIG. 4 is a flowchart illustrating a method for listening for sounds made by an infant near the remote unit of the child monitor system of FIG. 1.  
         [0012]    [0012]FIG. 5 is a flow chart illustrating a method for listening for fetal sounds of an unborn child using the local unit of the child monitor system of FIG. 1.  
         [0013]    [0013]FIG. 6 is a perspective view of an example embodiment of the child monitor system of FIG. 1.  
         [0014]    [0014]FIG. 7 is a frontal view of the local unit of the child monitor system of FIG. 1.  
         [0015]    [0015]FIG. 8 is a rear view of the local unit of the child monitor system of FIG. 1.  
         [0016]    [0016]FIG. 9 is a side view of the local unit of the child monitor system of FIG. 1.  
         [0017]    [0017]FIG. 10 is a frontal view of the remote unit of the child monitor system of FIG. 1.  
         [0018]    [0018]FIG. 11 is a side view of the remote unit of the child monitor system of FIG. 1.  
         [0019]    [0019]FIG. 12 is a rear view of the remote unit of the child monitor system of FIG. 1.  
         [0020]    [0020]FIG. 13 is a prospective view of the nursery monitor mode of the child monitor system of FIG. 1.  
         [0021]    [0021]FIG. 14 is a schematic view of another embodiment of a child monitor system.  
         [0022]    [0022]FIG. 15 is a flowchart illustrating a method for providing audio stimulation to an unborn child using the child monitor system of FIG. 14.  
         [0023]    [0023]FIG. 16 is a flowchart illustrating a method for recording sounds made by an infant using the child monitor system of FIG. 14.  
         [0024]    [0024]FIG. 17 is a flowchart illustrating a method for outputting recorded sounds made by an infant using the child monitor system of FIG. 14.  
         [0025]    [0025]FIG. 18 is a flowchart illustrating a method for recording and playing back sounds made by an unborn child using the child monitor system of FIG. 14.  
         [0026]    [0026]FIG. 19 is a schematic view of yet another embodiment of a child monitor system.  
         [0027]    [0027]FIG. 20 illustrates a first operating mode of the child monitor system of FIG. 19.  
         [0028]    [0028]FIG. 21 illustrates a second operating mode of the child monitor system illustrated in FIG. 19.  
         [0029]    [0029]FIG. 22 is a flowchart illustrating a method for providing sounds to an infant near the remote unit of the child monitor system of FIG. 19.  
         [0030]    [0030]FIG. 23 is a schematic view of yet another embodiment of a child monitor system.  
         [0031]    [0031]FIG. 24 is a schematic view of still another embodiment of a child monitor system.  
         [0032]    [0032]FIG. 25 illustrates a first operating mode of the child monitor system of FIG. 24.  
         [0033]    [0033]FIG. 26 illustrates a second operating mode of the child monitor system of FIG. 24.  
         [0034]    [0034]FIG. 27 illustrates a third operating mode of the child monitor system of FIG. 24.  
         [0035]    [0035]FIG. 28 illustrates a forth operating mode of the child monitor system of FIG. 24.  
         [0036]    [0036]FIG. 29 is a cross sectional schematic representation of the microphone of the local unit of the child monitor system taken along line A-A of FIG. 7. 
     
    
     DETAILED DESCRIPTION  
       [0037]    The present invention discloses a single device that may be used as either a prenatal monitor or a nursery monitor. The exemplary embodiments of the child monitor disclosed below include two units-a local unit and a remote unit. The user may use the device in one of two ways. First, the user can use the device to monitor a child located in another room of a home, for example. Alternatively, the user can use the device to listen to sounds made by a fetus in the mother&#39;s womb. To monitor a child located in another room, the user places the remote unit in the child&#39;s room and keeps the local unit in the user&#39;s location. The sounds will be transmitted from the remote unit to the local unit thus allowing the user to audibly monitor the child. To listen to prenatal sounds, the user places the remote unit next to the mother&#39;s abdomen. The remote unit receives and outputs sounds made by the fetus. While these are the most common functions, variations on the operation and functionality of the device are possible and are described in detail below.  
         [0038]    A first embodiment of a child monitor system  10  is illustrated schematically in FIG. 1. In this embodiment, the system may receive audio inputs from two sources and deliver a single audio output. The child monitor system  10  includes a remote unit  18 , having a first input transducer  20  and a transmitter  26 , and a local unit  28 , having a second audio input transducer  30 , conversion circuitry  36 , an output transducer  38 , a receiver  40 , and a selector  42 .  
         [0039]    The first audio input transducer  20  of the remote unit  18  converts an incident acoustic input into a first input signal. Acoustic input can include speech, crying, breathing, etc., from an infant or child. Likewise, the second audio input transducer  30  of the local unit  28  converts an incident acoustic input into a second input signal. This second input signal includes fetal heartbeat and other womb sounds, and these sound can be isolated or enhanced by filtering out other sounds.  
         [0040]    The conversion circuitry  36  converts the input signals into an output signal, which the output transducer  38  of the local unit  28  further converts into an acoustic output. From this configuration, the selector  42  allows a user to choose whether the system  10  will output the audio input from the local unit  28  or the audio input from the remote unit  18 . The second input signal can be communicated from the remote unit  18  to the local unit  28  via transmitter  26  and receiver  40 .  
         [0041]    [0041]FIG. 2 illustrates a first operating mode of the system of FIG. 1. The user has, via the selector  42 , chosen that the system  10  output the audio input  22  from the remote unit  18 . The audio input transducer  20  of the remote unit  18  receives a first acoustic input  22  and converts it to a first input signal  24 . The transmitter  26  of the remote unit  18  transmits this signal to the receiver  40  of the local unit  28 , which passes it on to the conversion circuitry  36 . The conversion circuitry  36  converts first input signal  24  into an output signal  37 , which the output transducer  38  then converts into an audio output  39 .  
         [0042]    [0042]FIG. 3, in contrast, illustrates a second operating mode for the configuration shown in FIG. 1. The user has chosen that the system  10  output the audio input  32  from the local unit  28 . In this mode, the second audio input transducer  30  of the local unit  28  receives a second acoustic input  32  and converts it to a second input signal  34 . The conversion circuitry  36  then converts this signal into an output signal  37 , which the output transducer  38  then converts into an audio output  39 .  
         [0043]    These operating modes allow the user the option of using the child monitor as a nursery room monitor or a prenatal monitor. The flowcharts of FIGS. 4 and 5 illustrate the operation of the system in these modes.  
         [0044]    [0044]FIG. 4 is a flowchart describing the operation of the system as a nursery room monitor, allowing a parent or user to listen to sounds made by an infant located near the child unit or monitor room sounds. As shown in operation  410 , the user places the remote unit in operative proximity to an infant, and, as shown in operation  412 , the audio input device of the remote unit receives the sounds of the infant&#39;s activities. The remote unit then transmits these signals to the receiver of the local unit as shown in operation  414 . The local unit&#39;s output transducer then outputs these sounds as shown in operation  416 .  
         [0045]    [0045]FIG. 5 is flowchart describing the operation of the system as a prenatal monitor for listing to sounds made by a fetus still in the mother&#39;s womb. The system does not require use of the remote unit in this mode. First, in operation  500 , the user places the audio input of the local unit adjacent to the mother&#39;s abdomen. The audio input receives the fetal sounds as shown in operation  502 . In so doing, the monitor uses RF high-pass and low-pass filters to focus on the fetal sounds. They filter out sounds below 30 Hz (which eliminates digestion sounds) and sounds above 1 KHz (eliminating ambient room noise). The fetal sounds are then amplified before being output by the audio output as shown in operation  508 . In one embodiment, the user receives this audio output through headphones.  
         [0046]    FIGS.  6 - 12  depict one implementation of child monitor system  10 . In the following discussion, the same reference numbers are used to identify components that correspond to those illustrated schematically in FIGS.  1 - 5 . The system  10  includes a local unit  28  and a remote unit  18 .  
         [0047]    Local unit  28  includes an audio input transducer  30 , a selector  42 , and an audio output transducer  38  (shown as  38 A and  38 B). Local unit  28  includes several visual displays and user controls. The displays include a POWER ON/LOW BATTERY LED  72  and a sound level indicator  74  implemented as a series of LEDs (preferably five, but more or fewer could be used). The user controls include an ON/OFF/VOLUME switch  70 , an A/B channel select switch and mode selector  42 .  
         [0048]    Audio input transducer  30  is implemented as a condenser microphone mounted on the front face of front housing  28 A of local unit  28 . The microphone is unidirectional and “floating,” i.e. isolated from its housing. In one embodiment, shown in FIG. 29 (the cross sectional viewpoint is shown in FIG. 7), the microphone  2904  is isolated from housing  2902  by a rubber ring  2906 . Rubber ring  2906  is soft without being fully compressible and has preferably a durometer reading of 20 to 30.  
         [0049]    In this implementation, audio output transducer  38  includes two alternative transducers,  38 A and  38 B. Transducer  38 A is a speaker (2″/5 cm) located behind the perforated front face of the housing of local unit  28 . Transducer  38 B is a pair of headphones (or multiple pairs of headphones) coupled to local unit  28  via a headphone jack  78 . In an alternative implementation, a recording device could be connected via headphone jack  78  to enable the audio signals to be recorded by an external recording device.  
         [0050]    Local unit  28  also includes antenna  76  and antenna retainer  88  disposed on rear housing  28 B. Flexible antenna  76  has a proximal end  82  coupled to the housing and a distal end  84  with a body  86  extending therebetween. A retainer  88  is coupled to the rear housing  28 B and is able to maintain the antenna in an alternative position adjacent the rear housing  28 B of the local unit  28 . Flexible antenna  76  is reconfigurable between a first configuration where the body  86  is spaced away from rear housing  28 B and a second configuration (illustrated in FIG. 13) where the body  86  of flexible antenna  86  is adjacent to rear housing  28 B within retainer  88 . As illustrated in FIG. 12 flexible antenna  76  in the second position assumes an arcuate shape with the distal end  84  contacting the supporting surface on which local unit  28  is situated. Alternatively, flexible antenna  76  may be shorter in length, where, while still maintaining an arcuate configuration, distal end  84  does not contact the supporting surface upon which local unit  28  is situated.  
         [0051]    Retainer  88 , which maintains the position of flexible antenna  86  in its folded configuration, may be a detent in the body of rear housing  28 B as illustrated in FIG. 8. Optionally, retainer  88  may be a clip (not shown) attached to the outside of rear housing  28 B. Flexible antenna  76  of this example embodiment of the local unit  28  desirably provides for reducing the volume required for the physical space where the local unit  28  is positioned.  
         [0052]    Power to the electronic components of local unit  28  is supplied by a main power supply which, in this example embodiment, consists of a 9V battery housed in battery compartment  80 , which is incorporated in rear housing  28 B.  
         [0053]    Remote unit  18  includes a front housing  18 A a rear housing  18 B, an audio input transducer  20 , an antenna  108 , and an AC power adapter  68 . Remote unit  18  also includes user controls and displays, including an ON/OFF switch  65 , an A/B channel select switch  63 , and a “POWER ON” LED  66 .  
         [0054]    Audio input transducer  20  of remote unit  18  is implemented as an omnidirectional condenser microphone mounted on the front face front housing  18 A.  
         [0055]    Power to the electronic components of remote unit  18  is provided by AC power adapter  68 . Internal DC power (such as batteries) could also be used.  
         [0056]    The transmitter and receiver circuitry used in the local and remote units may be any standard circuitry, as could be readily selected by the artisan. One suitable implementation is a 49 MHz system available from Excel Engineering, Ltd of Japan. Many other systems (including, for example, 900 MHz systems) are available from various suppliers.  
         [0057]    Similarly, any suitable system may be used for the conversion circuitry in the local unit, by which the inputs from either the remote unit or the local microphone are converted to output signals for the audio output transducer. For the audio input at the local unit, which detects fetal sounds, the monitor uses RF high-pass and low-pass filters to focus on the fetal sounds. The filters filter out sounds below 30 Hz (which eliminates digestion sounds) and sounds above 1 KHz (eliminating ambient room noise). The fetal sounds are then amplified before being output. One suitable system is also available from Excel Corporation, which is incorporated into the receiver circuitry described above.  
         [0058]    Child monitor system  10  is shown in FIG. 7 in the prenatal listening configuration. The user places audio input transducer  30  of local unit  28  on the abdomen of a pregnant woman and listens for fetal sounds via audio output transducer  38 A using headphones.  
         [0059]    Child monitor system  10  is shown in FIG. 13 in the nursery room monitor configuration. Remote unit  18  is placed in a room in proximity to a child the user wishes to monitor and local unit  28  is placed in a room where the user is located. In this mode, remote unit  18  receives, via audio input transducer  20 , sounds made by the child and transmits these sounds to local unit  28 . Local unit  28  outputs the sounds via audio output transducer (speaker)  38 A. In this mode, sound level indicator  74  on local unit  28  selectively illuminates some or all of the five constituent LEDs to give a visible indication of the level of sound received at the remote unit  28 . For example, a soft sound transmitted by the child unit will activate only the leftmost LED, however, more LEDs will be activated from left-to-right as a sound increases.  
         [0060]    Another embodiment of a child monitor system is illustrated schematically in FIG. 14. Child monitor system  110  is similar to child monitor system  10  described above except that the local unit  28  includes a memory  60  in which input signals from either unit may be stored prior to being output to the conversion circuitry  36 .  
         [0061]    This embodiment may be implemented in the same manner as child monitor system  10 . Memory  60  may be implemented in any of a number of ways that would be apparent to the artisan. One exemplary implementation could be a common digital recording integrated circuit such as a Winbond voice recorder with SRAM. In operation, the user pushes a record button to record and the system records sounds over sounds previously recorded and stored in the memory.  
         [0062]    This configuration allows the user to record and later play back audio stimulation to a fetus, or save and later playback sounds made by an infant near the remote unit. FIGS. 7, 8, and  9  are flowcharts describing these operations. This configuration also allows the user to record fetal sounds for later playback. As shown in FIG. 15, to provide audio stimulation to a fetus, the system first receives the sound the user wishes to provide to the fetus at the audio input shown in operation  718 . The system stores this sound in the memory and retrieves it when the user wishes to play it to the fetus. The flowchart depicts these steps in operations  720  and  722 , respectively. To play the sound to the fetus, the user places the audio output adjacent to the mother&#39;s abdomen as the system outputs the sounds through the audio output shown in operations  724  and  726 . In an alternative embodiment, audio stimulation to the fetus may be accomplished by using a external playback devices such as a CD or audio tape player connected to an audio input jack.  
         [0063]    [0063]FIGS. 16 and 17 describe recording and outputting sounds made by an infant located near the remote unit  18 . FIG. 16 describes the operation of the system to record sounds made by an infant. As shown in operations  834  and  836 , the system receives, at the remote unit  18 , sounds made by an infant and transmits these sounds to the local unit  28 . The system then stores these sounds in the memory  60  shown in operation  838 . Turning to FIG. 17, in order to output these recorded sounds, the system retrieves the infant sounds from the memory  60 , shown in operation  940 , and outputs the sounds at the audio output  38  of the local unit  28 , shown in operation  942 .  
         [0064]    In addition to the operations described in FIGS.  15 - 17 , FIG. 18 is a flowchart illustrating a method for recording sounds made by a child still in the mother&#39;s womb. The user places the audio input device  30  of the local unit  28  adjacent to the mother&#39;s womb, and the audio input device  30  receives sounds made by the fetus as shown in operations  1000  and  1002 , respectively. In operation  1004 , the memory  60  stores these sounds, and, when the user decides to playback the recorded sounds, the system  110 , as shown in operation  1006 , retrieves the sounds from the memory  60 , and outputs the fetal sounds, shown in operation  1008 .  
         [0065]    [0065]FIG. 19 schematically illustrates yet another embodiment of the child monitor system. In this embodiment, the system  210  may receive one audio input and deliver outputs to two locations. Thus, this configuration allows the user to select, via the selector  42 , whether the system  210  will output the acoustic input from the local unit  28  or the remote unit  18 . The local unit  28  includes an audio input transducer  30 , first conversion circuitry  36 , a first output transducer  38 , a transmitter  47 , and a selector  42 . The remote unit includes a receiver  46 , second conversion circuitry  110 , and a second output transducer  112 .  
         [0066]    System  210  may be implemented in the same manner as that of system  10  described above and depicted in FIGS.  6 - 13 . Second conversion circuitry  110  and second output transducer  112  may be the same as or similar to that of conversion circuitry  36  and output transducer  38  of local unit  28 . The artisan could select several implementations of second conversion circuitry  110  and output transducer  112 . One exemplary implementation for the output transducer could be a speaker located within remote unit  18  or headphones, for example.  
         [0067]    The user may select multiple operating modes from this configuration, and FIG. 20 depicts a first operating mode. Here, the user has selected that the system  210  output an audio signal from the local unit  28 . The audio input transducer  30  of the local unit  28  receives an audio input signal  232  and converts it into an input signal  234 . The conversion circuitry  36  converts this signal to an output signal  237 , which the audio output transducer  38  then converts into an acoustic output  239 .  
         [0068]    [0068]FIG. 21 illustrates a second operating mode using the same configuration. In this mode, the user has selected that the remote unit  18  deliver the acoustic output. The audio input transducer  30  of the local unit  28  receives an acoustic input  232  and converts it into an input signal  233 . The transmitter  47  transmits this signal to the receiver  46 . Conversion circuitry  110  of the remote unit  18  then converts the signal into an output signal  235 , and the output transducer  112  outputs an acoustic output  239 .  
         [0069]    With this configuration, the user, at the local unit  28 , may provide sounds to a child located near the remote unit  18 . FIG. 22 is a flowchart which describes this operation. First, in operation  1428  the user places the remote unit in operative proximity to an infant. The local unit then transmits the sound to the remote unit  18  shown in operation  1430 , and the remote unit  18  outputs the sounds from a audio output  205  shown in operation  1432 .  
         [0070]    [0070]FIG. 23 shows a further modification of the configuration of the child monitor system  310 . In this modification, local unit  28  includes a memory  60  in which the input signal may be stored prior to being output to the conversion circuitry  36  or transmitted to the remote unit  18 . System  310  may also be implemented in the same manner as described above for system  10  and shown in FIGS.  6 - 13  and memory  60  in the same manner as described above for system  110 .  
         [0071]    Another embodiment of the present invention is illustrated in FIG. 24. In this embodiment, the local and remote units both have audio input transducers  30  and  20 , output transducers  38  and  112 , transmitters  160  and  26 , receivers  40  and  162 , and conversion circuitry  36  and  110 . This configuration, which may also be implemented in the same manner as described above for system  10  and shown in FIGS.  6 - 13 , allows the user to select multiple input-output combinations, the operation of which will be described below.  
         [0072]    Transmitter  160  and receiver  162  may be implemented in the same manner as transmitter  26  and receiver  40 . In one embodiment, the two way communication is implemented using half duplex two-way communication that uses automatic switching on a 30 ms duty cycle. This system is biased toward receiving rather than transmitting. An artisan, however, will realize that full-duplex two-way communication could also be used to allow signals to be transmitted and received simultaneously.  
         [0073]    [0073]FIG. 25 illustrates an operating mode of the present invention using the configuration described above in which the system transmits the audio input  432  received by the audio input transducer  30  of the local unit  28  to the remote unit  18  for output. The transmitter  160  of the local unit  28  transmits the audio input signal  432  to the receiver  162  of the remote unit. The conversion circuitry  110  of the remote unit  18  converts the audio input signal into an output signal  419 , which the output transducer  112  converts into an audio output signal  453 .  
         [0074]    [0074]FIG. 26 depicts the operation just described, but in reverse. Here, the audio input  422  received by the audio input transducer  20  of the remote unit  18  converts the audio input into an input signal  424 . The transmitter  26  of the remote unit  18  transmits this signal to the receiver  40  of the local unit  28 . The conversion circuitry  36  of the local unit  28  converts this signal into an output signal  437 , which the output transducer  38  of the local unit  28  converts into an audio output  439 .  
         [0075]    [0075]FIGS. 19 and 20 illustrate operating modes of the child monitor system  410  of FIG. 26 in which no transmission is involved. In figure FIG. 27 the audio input transducer  30  of the local unit  28  receives an audio input signal  432  and converts it to an input signal  434 . The conversion circuitry  36  of the local unit  28  converts the signal into an output signal  437 . The output transducer  38  of the local unit  28  then converts the signal into an audio output  439 .  
         [0076]    [0076]FIG. 28 illustrates the same operation, but at the remote unit. Here, the audio input transducer  20  of the remote unit  18  receives an audio input signal  422  and converts it to an input signal  434 . The conversion circuitry  110  of the remote unit  18  converts the signal into an output signal  437 . The output transducer  349  of the remote unit  18  then converts the signal into an audio output  439 .  
         [0077]    While example embodiments have been illustrated and described above, those of skill in the art will understand that various changes in detail and in the general construction and arrangement of the invention may be made without departing from the spirit and scope of the invention as described in the following claims.