Abstract:
A baby monitor for monitoring sounds wherein the monitor comprises a first base and a second base each having a microphone for detecting sound and a radio component for broadcasting the detected sound as a unique radio signal unique to each base. The baby monitor also has a receiver which contains a speaker for broadcasting a reproduction of the detected sound, a first indicator light to indicate if the unique radio signal is a first unique radio signal, a second indicator light to indicate if the unique radio signal is a second unique radio signal, and a vibrating motor which issues a first vibratory alert when a first unique radio signal is received and a second vibratory alert when a second unique radio signal is received.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Technical Field  
         [0002]     The present invention relates to the field of monitoring devices, and more particularly, to a baby monitor for use in combination with at least two bases used to monitor the sounds made by a baby where a receiver produces a visual, audio, vibratory, or combinations thereof alert when a signal is received from one of the bases.  
         [0003]     2. Description of Related Art  
         [0004]     It is important for a care giver to monitor their charges such as infants, children, babies, incapacitated persons, etc. as closely as possible. Although it would be ideal to monitor a subject constantly, it is difficult to accomplish such intensive monitoring without the assistance of specialized monitoring equipment such as a baby monitor.  
         [0005]     A standard baby monitor consists of a base and a receiver, each of which can be powered by a battery or an A/C current source, usually with an inline transformer, and is basically a combination microphone and radio transmitter/receiver. The base contains a microphone or other sound detecting device and is placed in a location near an infant or baby. The receiver contains a speaker and is placed in a location near a care giver. The base receives a sound such as a stirring or crying baby, converts it to an electrical signal, then to a radio signal and broadcasts the radio signal on a specific frequency to the receiver. The receiver receives the radio signal from the base, converts it to an electrical signal and sends that signal to a speaker, where it is converted into a sound for the care giver to hear and respond accordingly.  
         [0006]     By feeding an electrical signal to the radio components of the base, radio waves are produced. The electrons made by the electrical signals in the metal atoms of an antenna change energy levels and emit radio waves. The bases broadcasts radio waves that are modulated which means the original sound signal is superimposed on the radio wave so that the radio wave “carries” the sound.  
         [0007]     The receiver is basically a transmitter in reverse. The antenna is struck by the radio waves connected to the receiver. The radio waves affect the metal atoms, producing weak electric carrier signals in the antenna. The radio components extract the sound signal from the carrier signal, and this signal goes to an amplifier and speaker to reproduce the sound.  
         [0008]     Like all waves, radio waves have a particular wavelength or frequency. The 43-50 MHz band is common in early cordless telephones and less expensive baby monitors. Because of the low frequency, these baby monitors have short ranges (about 1,000 ft/330 m) and poorer sound quality due to interference from structures and appliances. The 43-50 MHz phone signals can also be picked up easily on radio scanners, early cordless telephones, and similar nearby baby monitors.  
         [0009]     The 900 MHz band (actually 900-928 MHz) is a common frequency for cordless phones and mid-ranged baby monitors. The higher frequency gives the baby monitor a greater range (5,000 to 7,000 ft/1,500 to 2,100 m) and better sound quality. However, 900 MHz signals can be picked up easily by most commercially available radio scanners.  
         [0010]     In 1998, the FCC opened up the 2.4 GHz range for cordless phone and baby monitor use. A 2.4 GHz or 5.8 GHz baby monitor can operate over a greater distance and is above the frequencies that can be picked up by most commercially available radio scanners; therefore, it is more secure than lower frequency models.  
         [0011]     Each frequency band (43-50 MHz, 900 MHz, 2.4 GHz or 5.8 GHz) can be subdivided into different increments or channels. For example, on some baby monitor models, the base searches for a pair of frequencies (channels) within a range, that is not already in use, to transmit to the receiver. If the base is capable of searching more increments, it can more easily find a frequency pair that is clear from interference, providing better sound quality. The number of baby monitor channels can vary as follows: 10 to 25 channels—43-50 MHz phones and some inexpensive 900 MHz phones; 20 to 60 channels—most 900 MHz phones; 50 to 100 channels—high-end 900 MHz and 2.4/5.8 GHz phones.  
         [0012]     Most baby monitors include a plurality of light emitting diodes (LEDs), which light in series to indicate the level of the sound received by the receiver. This acts as a visual alert for the care giver in that as the sound level increases the number of LEDs that light also increases. As an added alert the color of the subsequently lit or higher sound-level LEDs is a different color from the lower sound-level LEDs (usually red and green, respectively). This visual alert is useful in an environment where there are other noises that may cause the receiver output to go unheard by the care giver. These other noises can be the sound from a television, radio, stereo, or other electronic device. These external noises can also be from noise-making electric appliances, for example, an electric mixer, a blender, a washing machine, or the like. However, often it is difficult to constantly watch the baby monitor to see the visual alert.  
         [0013]     If the external noises are greater then the output of the baby monitor receiver, the sounds of the baby can go unheard by the care giver. Also, a problem with the LED model in particular arises when external noises are present and the receiver is out of the line-of-sight of the care giver. In this case, along with the sound going unheard, the visual alert goes unseen. Thus, in either case the baby could be crying and the care giver would be unaware of this potentially dangerous situation. Therefore, some baby monitors, such as the Fisher-Price® 900 MHz Long-Range Monitor Model B1474 have a vibrating alert.  
         [0014]     The base of a baby monitor is not easily transported from room to room. If an infant or baby is going to be moved to a different room, then the base must also be moved to that room. It is difficult for busy care givers to remember to move the base each time the baby is moved. Also, some care givers have more than one child and unless each child is in the same room, then more than one baby monitor system is required to monitor the infant or baby. When more than one baby monitor system is used, the care giver is require to have a receiver for each base used, and it is difficult to keep up with multiple monitors.  
         [0015]     Therefore, what is needed is a receiver that can receive the signal from more than one base. Because care givers must shower or be near water, it would also be a benefit if the receiver had a waterproof housing to allow the care giver to shower or be near water without having to forego use of the baby monitor. Also, it would be beneficial if the receiver would give multiple alert signals such as visual, audio, and vibratory.  
       SUMMARY OF THE INVENTION  
       [0016]     The present invention is a baby monitor which has two or more bases and a receiver capable of detecting the unique radio signal sent from each base. The receiver is small in size and has a water proof housing to allow the care giver to shower or be near water without having to forego use of the baby monitor. The receiver provides at least three alert signals: visual, audio, and vibratory. Preferably the visual and vibratory signals are unique to the base that sent the radio signal.  
         [0017]     In use, when one base detects a sound, the base sends out a radio signal on a frequency unique to the base. The receiver receives the radio signal and uses the unique frequency to determine what base the radio signal came from. Once the receiver determines what base the radio signal came from, the speaker reproduces the detected sound and the receiver activates a visual and vibratory alert unique to the base. The care giver can hear the sound, see the unique visual alert and/or feel the unique vibratory alert and is able to determine what base detected the sound and thereby can respond accordingly.  
         [0018]     Because the receiver can detect the signal from multiple bases, the care giver does not have to move a base each time the infant or baby changes rooms. Also, the care giver does not have to carry around multiple receivers to monitor multiple bases.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]     The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, wherein:  
         [0020]      FIG. 1  is a plan view of a monitor system in accordance with the present invention;  
         [0021]      FIG. 2  is a block diagram of an interior of a base of the present invention;  
         [0022]      FIG. 3  is a block diagram of an interior of a receiver of the present invention;  
         [0023]      FIG. 4  is a plan view of a receiver in use with a recharging station of the present invention; and  
         [0024]      FIG. 5  is a plan view of a receiver in use with a movement monitor of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0025]     In the descriptions that follow, like parts are marked throughout the specification and drawings with the same numerals, respectively. The drawing figures are not necessarily drawn to scale and certain figures may be shown in exaggerated or generalized form in the interest of clarity and conciseness.  
         [0026]     As shown in  FIG. 1 , the baby monitor includes bases  104   a  and  104   b  and one receiver  106 . More bases and more receivers could be used and such use will be described in detail further below. Bases  104   a  and  104   b  are typical bases found with most baby monitors known in the art and each one is able to transmit on its own unique fixed frequency. The unique frequency can be any frequency allowed by the FCC but is preferably the highest frequency allowed such as 2.4 GHz or 5.8 GHz.  
         [0027]     The 2.4 GHz or 5.8 GHz frequency allows increased distance over which the monitor can operate and is out of the frequency range of most radio scanners, thereby providing increased security from radio scanners. For additional security, the baby monitor uses a digital spread spectrum (DSS) as is known in the art. DDS enables the signal sent from bases  104   a  and  104   b  to receiver  106  to be spread in “pieces” over several frequencies, thereby deterring or more preferably making it almost impossible to eavesdrop on the baby monitor.  
         [0028]     Receiver  106  is able to receive the unique frequency sent from base  104   a  and the unique frequency sent from base  104   b . For example, if base  104   a  transmits at 901 MHz and base  104   b  transmits at 902 MHz, receiver  106  can receive both signals.  
         [0029]     Receiver  106  contains indicator lights  208   a  and  208   b . Indicator lights  208   a  and  208   b  may be liquid crystal displays (LCDs), light-emitting diodes (LEDs), or some other similar type indicator light. Indicator light  208   a  produces a first unique visible indicator when base  104   a  transmits a signal. Indicator light  208   b  produces a second unique visible indicator when base  104   b  transmits a signal.  
         [0030]     As shown in  FIG. 2 , base  104   a  includes power components  204 , battery charger  206 , indicator lights  208 , microphone  210 , radio components  212 , base antenna  214 , processor  216 , and electrical wire  218 . For clarity and conciseness, a detailed description of base  104   b  is omitted. Base  104   b  is the same as base  104   a  except base  104   b  is in a different location than  104   a  and transmits on a different frequency.  
         [0031]     Power components  204  supply low voltage power to the circuits and recharges the battery of the receiver  106 . A typical DC power cube transformer as known in the art supplies the low voltage required by the electrical components of base  104   a . The power components on the processor  216  work with the power cube to supply electrical current to re-charge the battery of the receiver  106 . Power components  204  supply power to all the necessary components of base  104   a  via electrical wires  218 .  
         [0032]     Battery charger  206  is compatible with the rechargeable battery  308  in the receiver  106 . Battery  308  may be a AAA or AA Nickel-cadmium battery, Nickel-metal hydride battery, Lithium-ion battery, Zinc-air battery, or any other rechargeable battery known in the art. Battery charger  206  recharges the battery  308  as is known in the art.  
         [0033]     Processor  216  is suitable for enabling all electronics and electrical function of the baby monitor and is a typical commercially available processor well known in the art, examples include processors from Atmel, Inc. located at 2325 Orchard Parkway, San Jose, Calif. 95131 USA or ZiLOG, Inc. located at 532 Race Street San Jose, Calif. 95126. Further description of the electronics and processor  216  hardware and software for operating base  104   a  as a base for a baby monitor is not necessary for one of ordinary skill in the art to make and use the inventions disclosed herein.  
         [0034]     Indicator lights  208  may be liquid crystal displays (LCDs), light-emitting diodes (LEDs), or some other similar type indicator light. Indicator lights  208  indicate whether or not base  104   a  is receiving power and if the receiver  106  is charging.  
         [0035]     Microphone  210  electronically receives varying pressure waves in the air caused by sound in the vicinity of base  104   a  and converts them into varying electrical signals. Microphone  210  is preferably an omnidirectional microphone that picks up sound from all directions and has a diaphragm that is vibrated by sound waves in the vicinity of base  104   a . The sound waves make tiny electric currents either by moving a coil of wire within a magnet or by compressing the membrane against carbon dust.  
         [0036]     Microphone  210  is a typical commercially available microphone, and may be a carbon microphone, dynamic microphone, ribbon microphone, condenser microphone, crystal microphone or any other microphone known in the art such as the Panasonic WM-64PCTM omnidirectional miniature electret microphone available from Panasonic Matsushita Electric Corporation of America located at One Panasonic Way, Secaucus, N.J. 07094 or the Horn Electret Condenser Microphone available from Mouser Electronics, Inc. located at 1000 North Main Street Mansfield, Tex. 76063. The electrical signals from microphone  210  are sent to the audio amplifier in radio components  212  via electrical connection  218 .  
         [0037]     Radio components  212  amplify the electrical signals from microphone  210  and convert them to radio waves. The radio waves are then broadcast to the receiver  106  via base antenna  214 . Radio components  212  may use quartz crystals to set the radio frequencies for sending and receiving signals.  
         [0038]     In a second embodiment, base  104   a  uses filtration electronics to determine the best frequency to send the signal. Such use of filtration electronics is known in the art. After the radio waves are broadcast from base  104   a  via base antenna  214 , the radio waves are detected by receiver antenna  304  on receiver  106  shown in  FIG. 3 .  
         [0039]     Receiver  106  contains receiver antenna  304 , battery  308 , indicator lights  310   a ,  310   b , and  310   c , radio components  312 , processor  314 , speaker  316 , vibrating motor  318  and volume control knob  322 . All electric components are operationally connected together by electrical wires  324 . Casing  320  surrounding receiver  106  is a waterproof casing.  
         [0040]     The receiver  106  may be battery powered or have a connection for plugging into an electrical wall outlet or both. A typical DC power cube transformer as known in the art supplies the low voltage required by the electrical components via electrical wires  324 .  
         [0041]     Battery  308  can be a AAA, AA, or any other sized battery and may be a nickel-cadmium, Nickel-metal hydride, Lithium-ion, Zinc-air, or any other similar battery known in the art for use in small personal electronics. Preferably, battery  308  is a rechargeable battery such as the Nickel Metal Hydride (NiMH) AAA rechargeable battery available from Rayovac Corporation located at Six Concourse Parkway, Suite 3300, Atlanta, Ga. 30328 or the NIMH AAA rechargeable battery available from NEXcell® Battery Co., Ltd. located at 1251 Shamrock Avenue, Monrovia Calif. 91016. Battery  308  supplies the power for all of the electrical components in the receiver  106 . When the battery runs low, indicator light  310   c  begins to dim or flash. If a rechargeable battery is low, it can be recharged on the base  104   a  or  104   b . When receiver  106  is on a base recharging, receiver  106  can receive signals from another base. However, to avoid feedback problems, receiver  106  cannot receive signals from the base it is recharging in. For example, if receiver  106  is recharging in base  104   a , then receiver  106  can receive signals from base  104   b  but cannot receive signals from base  104   a.    
         [0042]     Antenna  304  is made from a coil of wire wrapped around a metal core and can receive the radio signal from the base  104   a  and  104   b . The received radio signal is sent to radio components  312  where is it converted into an electrical signal and sent to processor  314 .  
         [0043]     Processor  314  is suitable for enabling all electronics and electrical function of receiver  106  and is a typical commercially available processor well known in the art, examples include processors from Atmel, Inc. located at 2325 Orchard Parkway, San Jose, Calif. 95131 USA or ZiLOG, Inc. located at 532 Race Street, San Jose, Calif. 95126. Further description of the electronics and processor  314  hardware and software for receiver  106  as a receiver for a baby monitor is not necessary for one of ordinary skill in the art to make and use the inventions disclosed herein.  
         [0044]     Processor  314  determines what base the signal came from and sends an alert using one or more of three methods: audio, visual or vibratory. If the signal came from base  104   a , then a signal is sent from processor  314  to indicator light  310   a  causing indicator light  310   a  to glow resulting in a visual alert, to speaker  316  causing the speaker to recreate the sound detected in the vicinity of base  104   a , and to vibrating motor  318  causing a unique vibratory alert. If the signal came from base  104   b , then a signal is sent from processor  314  to indicator light  310   b  causing indicator light  310   b  to glow resulting in a visual alert, to speaker  316  causing the speaker to recreate the sound detected in the vicinity of base  104   b , and to vibrating motor  318  causing a unique vibratory alert different from the one used when the signal came from base  104   a.    
         [0045]     Indicator lights  310   a  and  310   b  may be liquid crystal displays (LCDs), light-emitting diodes (LEDs) or some other similar type indicator light. Indicator light  310   a  emits a different color than indicator light  310   b  which gives a unique visual signal for each indicator light.  
         [0046]     Because base  104   a  and  104   b  broadcasts radio waves that are modulated, meaning the original sound signal is superimposed on the signal, receiver  106  is able to detect the volume of the original sound. When the volume of the sound is relatively low, processor  314  sends a relatively low voltage signal to indicator light  310   a  or  310   b , speaker  316 , and vibrating motor  318 . The relatively low voltage signal causes indicator light  310   a  or  310   b  to emit a relatively dim glow, speaker  316  to produce a relatively low volume sound, and vibrating motor  318  to vibrate at a relatively low intensity.  
         [0047]     When the volume of the sound is relatively high, processor  314  sends a relatively high voltage signal to indicator light  310   a  or  310   b , speaker  316 , and vibrating motor  318 . The relatively high voltage signal causes indicator light  310   a  or  310   b  to emit a relatively bright glow, speaker  316  to produce a relatively high volume sound, and vibrating motor  318  to vibrate at a relatively high intensity.  
         [0048]     Therefore, intensity of the visual, audio, and vibratory alert increase as the volume of the sound detected by base  104   a  or  104   b  increases. As is known in the art, the sound reproduced on speaker  316  will have relatively the same volume as the sound detected by base  104   a  or  104   b . The volume of the sound reproduced by the speaker is also controlled through volume control knob  322 .  
         [0049]     Speaker  316  is a commercially available speaker known in the art such as the 8 ohm, 0.1 watt speaker catalog number SK-218 available from All Electronics Corp. located at 14928 Oxnard St. Van Nuys, Calif. or Kobitone Speaker SPKR 8 OHM 1 W 16×35 MM. Speaker  316  receives the electrical signals from the processor  314  via electrical wire  324  and converts the electrical signal into sound.  
         [0050]     The electrical signals from processor  314  travel to a coil of copper wire and induce magnetic currents in the coil of wire, thereby making it an electromagnet. The electromagnetic coil moves in and out of grooves within a permanent magnet. This moves an attached plastic membrane in and out at the same frequencies as the changes in electric currents. The movements of the membrane move air at the same frequencies, thereby creating sound waves that can be heard and reproduce the sound detected by base  104   a.    
         [0051]     Vibrating motor  318  contains a small DC motor that drives a gear attached to the motor&#39;s spindle which is connected to a small weight. The weight is mounted off-center on the motor&#39;s spindle and when the motor spins the weight. The off-center mounting causes a strong vibration.  
         [0052]     Vibrating motor  318  is a typical vibrating motor commercially available and known in the art such as the dual, monostable multivibrator, catalog number MC 14528 available from All Electronics Corp. located at 14928 Oxnard St., Van Nuys, Calif. 91411 or the Fairchild VHC/VHCT CMOS Logic SOIC-16 Dual Multivibrator available from the FairChild Corporation located at 1750 Tyson&#39;s Blvd Suite 1400, McLean, Va. 22102. Vibrating motor  318  can vibrate at different speeds such as fast or slow or any combination of fast then slow or slow then fast. Because vibrating motor  318  can vibrate at different speeds, a unique vibratory alert can be used for the bases  104   a  and  104   b.    
         [0053]     In another embodiment, shown in  FIG. 4 , receiver  106  may be recharged in a recharging station  404 . Recharging station  404  may be battery powered or have a connection for plugging into an electrical wall outlet or both. Recharging station  404  contains indicator lights  406   a  and  406   b  and speaker  408 .  
         [0054]     When receiver  106  is placed in recharging station  404 , the processor  314  detects recharging station  404  and instead of sending alert signals to indicator light  310   a  and  310   b  and speaker  316  the signals are sent to indicator lights  406   a  and  406   b  and speaker  408 . No vibratory signal is given. Indicator lights  406   a  and  406   b  are similar to and operate in the same manner as indicator lights  310   a  and  310   b  respectively. Speaker is similar to and operates in the same manner as speaker  316 . When receiver  106  is in recharging station  404 , no signal is sent to vibrating motor  318 .  
         [0055]     In another embodiment, shown in  FIG. 5 , receiver  106  is configured to receive signals from movement monitor  502  as is known in the art. Such movement monitors operate in a similar function to the base  104   a  and emit a radio signal at a unique predetermined frequency. Receiver  106  is tuned to receive the unique frequency sent by movement monitor  502  and give the appropriate alert based on the unique frequency.  
         [0056]     Although the invention has been described with reference to one or more preferred embodiments, this description is not to be construed in a limiting sense. There is modification of the disclosed embodiments, as well as alternative embodiments of this invention, which will be apparent to persons of ordinary skill in the art, and the invention shall be viewed as limited only by reference to the following claims.