Patent Publication Number: US-2002003478-A1

Title: Infant monitoring system

Description:
TECHNICAL FIELD  
       [0001] The present invention relates to a multi-function system for monitoring the status of an infant, and more particularly to an apnea and urinary wetness detecting system which can generate an alarm signal and transmit it to remote receivers.  
       BACKGROUND OF THE PRESENT INVENTION  
       [0002] Breathing is essential to life. Normal and continuous breathing is an important symbol of health. Clinical medical data shows that apnea or cessation of breathing can occur in infants having an incomplete breathing center. If apnea is not noted and treated immediately, the continued lack of oxygen may cause the necrosis of the infant&#39;s brain cells and may even result in the infant&#39;s sudden death.  
       [0003] It is also important for the health of an infant that its diaper be changed promptly when it is wet as the very delicate skin of an infant&#39;s buttocks is prone to inflammation caused by wetness. A slight inflammation may cause an itch which can affect the infant&#39;s sleep. In addition, if the inflammation is left untreated, a severe infection or septicemia may develop that might endanger the infant&#39;s life. Therefore, it is desirable that a monitoring system be utilized for monitoring an infant that is capable of detecting both apnea, which can cause the sudden death of the infant, and urination, which can lead an infection and possible septicemia.  
       SUMMARY OF THE PRESENT INVENTION  
       [0004] It is therefore a principle object of the present invention to provide an infant monitoring system for detecting apnea and urinary wetness, and providing an indication of either condition, e.g., by activating an alarm.  
       [0005] A further object of the present invention is to provide an infant monitoring system that can produce audible-visual alarm at the site of the infant and transmit signals to remote receivers.  
       [0006] It is still a further object of the present invention to utilize coded signals so as to reduce the likelihood of false alarms at the remote receivers.  
       [0007] It is yet another object to provide an infant monitoring system which is reliable and easy to use.  
       [0008] In accordance with a disclosed embodiment of the present invention, a reliable, convenient infant monitoring system is provided that is capable of detecting both apnea and urinary wetness of an infant. Advantageously, one integrated device is used, and either detected condition generates an alarm signal. Such signal, in the form of an audible and/or visible alarm, may be provided at a local site, i.e., one proximate to the infant, and/or transmitted to a site that is remote from the infant. The above-described system is also applicable for use with others, such as the elderly and infirm who are unable to care for themselves. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0009]FIG. 1 is a perspective view of an infant monitoring system including a processing device and a radio receiver in accordance with the present invention.  
     [0010]FIG. 2 is a block diagram of the processing device and radio receiver of FIG. 1.  
     [0011]FIG. 3 is a block diagram showing the operation of transmitting and receiving coded signals in accordance with a disclosed embodiment of the present invention.  
     [0012]FIG. 4 is a circuit diagram of the circuit board in the processor of FIG. 1.  
    
    
     DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT  
     [0013] Refer to FIG. 1. An exemplary embodiment of an infant monitoring system in accordance with the present invention includes processing device  4 , breathing sensor  1 , urinary wetness sensor  2  and radio receiver  13 . Processing device  4  comprises a circuit board  7  for receiving and analyzing sensed data from breathing sensor  1  and urinary wetness sensor  2 , and a radio transmission module  3  for sending a radio alarm signal. It also contains a set of batteries  8 , a power source switch  6 , a DC voltage indication light  9  and infant status indication lights  5 . Radio receiver  13 , comprising radio receiving module  10 , battery  14 , power source switch  11  and indication light  12 , is designed for receiving a radio signal from processing device  4  and then activating an audible-visual alarm. It can be seen that breathing sensor  1  and urinary wetness sensors  2  are respectively connected to processing device  4 , which continuously collects and analyzes sensed data about the status of the infant. If any abnormal status of an infant is detected, processing device  4  will generate an alarm by activating an indication light and a buzzer. In addition, a radio signal will be transmitted to one or more remote receivers.  
     [0014] In a preferred embodiment of the present invention, breathing sensor  1  is a strain type. A strain sheet is placed on an elastomer. The elastomer, together with the strain sheet, is housed inside a soft enclosure that is applied to an infant&#39;s abdomen with a strap. The breathing rhythm of an infant is then detected by sensing variations in the curvature of the infant&#39;s abdomen. The wetness sensor, on the other hand, makes use of the fact that urine conducts electrical signals. The urinary wetness sensor  2  operates by detecting the variations in the resistance of a resistor produced by the urine and then sending a indicative of such variations to processing device  4  for analyzing.  
     [0015] As shown in FIG. 2, circuit board  7  includes an integrated circuit (“IC”) module  201 , a constant current source circuit  202 , a urinary wetness detecting circuit  203 , an audible-visual alarm circuit  204 , a low DC voltage indication circuit  205  and a radio transmission module  206 . The output of breathing sensor  1  is fed to an input of the IC module  201 . Another input into the IC module is a sensed signal from urinary wetness sensor  2  via the urinary wetness detecting circuit  203 . One of the outputs of the IC module is fed to the audible-visual alarm circuit  204  and to the radio transmission module  206  to generate and transmit an alarm. Another output of the IC module  201  is coupled to the low DC voltage indication circuit  205  for activating an indication light. The constant current source circuit  202  provides breathing sensor  1  with a constant current.  
     [0016] The IC module  201 , in the exemplary embodiment of the present invention, is module designated as “HS 01 ” and produced by the Beijing Fengyang Science &amp; Technology Development Co. Ltd., Beijing, China. Module HS 01  can detect a sensed signal from breathing sensor  1  at a rate of 5 times per second, and can store the results as data in its memory for 15 seconds. After this time period, the stored data is updated with new data. HS 01  monitors and analyzes the status of an infant by comparing newly detected data from the breathing sensor  1  with previously stored data from such sensor. If an analysis shows no variation in the curvature of the infant&#39;s abdomen, indicating that the abdomen of the infant has no motion and that breathing has stopped, an alarm signal will be activated by module HS 01 . This signal drives the audible-visual alarm circuit  204  to sound an alarm and the radio transmission module  206  to send a radio alarm signal. In addition, when the breathing rhythm of the infant exceeds 60 times per minute, indicating quicker breathing than normal, module HS 01  will also generate an alarm signal.  
     [0017] If none of above circumstances happens, module HS 01  will send out a signal indicating that the infant is in a normal condition. Accordingly, a breathing indication light will alternate between on and off in synchronism with the infant&#39;s breathing.  
     [0018] Similarly, module HS 01 , through the urinary wetness detecting circuit  203 , analyzes the signal from urinary wetness sensor  2 . When urination of the infant is detected, it will activate the audible-visual alarm circuit  204  to produce an alarm and drive the radio transmission module  206  to send a radio alarm signal.  
     [0019] Radio receiver  13  includes a receiving module  207  for receiving the radio signal transmitted from processing device  4  and an audible-visual circuit  208  for sounding an alarm. Accordingly, the radio receiver  13  may drive its own audible-visual circuit  208  to indicate an alarm.  
     [0020] Refer now to FIG. 3. Radio transmission module  206  comprises a digital encoding circuit  301 , a microwave modulation circuit  302  and a power amplification circuit  304 . Correspondingly, the radio receiving module  207  includes a high-frequency amplification and mixing circuit  305 , a demodulation/decode circuit  306  and a driving circuit  307 . An oscillation circuit  308  provides an oscillation source for the high-frequency amplification and mixing circuit  305 . A detecting signal from the low DC voltage detection circuit  309  is fed to an input of driving circuit  307 , which, in turn, activates an audible-visual alarm circuits  310  and  311 . Sound indication circuit  310  broadcasts an audio alarm while light indication circuit  311  broadcasts a visual alarm. The use of digital encoding/decoding, wherein a coded signal is transmitted to and received by radio receivers, advantageously eliminates or reduces the effects of radio interference so as to prevent or substantially reduce the likelihood of an incorrect alarm signal being generated by the radio receiver.  
     [0021] Refer now to FIG. 4 that illustrates the electrical circuit on the circuit board  7  in accordance with a disclosed embodiment of the present invention. As a core portion for realizing the functions of the present invention, module HS 01  is employed for processing sensed data. A program stored in its memory is used to compare inputted new data with stored data, which will not be covered or updated by new data until it has been reserved for a predetermined time. The analytical result will determine whether or not the infant is in a normal status.  
     [0022] Breathing sensor  1  and urinary wetness sensor  2  are connected to circuit board  7  via connecting pins XP 1 . More particularly, input terminals  2 ,  3  and  6  of module HS 01  are coupled to the output of breathing sensor  1 . Input terminal  11  of module HS 01  receives outputted signals from urinary wetness sensor  2  via the urinary wetness detecting circuit  203 , which is comprised of R 9 , C 1  and N 1 . While output terminals  23 ,  18  and  19  are used to activate the audible-visual alarm circuit  204 , output terminal  22 , via resistor R 20  and triode N 11 , is connected to radio transmission module  206  for energizing the radio alarm signal. The constant current source circuit  202 , composed of voltage stabilization integrated circuit N 2  and resistor R 4 , provides breathing sensor  1  with a constant current.  
     [0023] Terminal  6  of module HS 01  is used for recognizing the appearance of breathing sensor  1 . If no breathing sensor is connected, module HS 01  will operate only for detecting urinary wetness. When the urinary wetness reaches predetermined threshold, which can be detected by input terminal  11  of module HS 01 , an alarm signal will be initiated. LEDs (light emitting diodes) N 5 , N 6 , N 7  and N 8  are used for indicating the status of the infant. In particular, LED N 5  is designed for indicating the rhythm of breathing, while LEDs N 6  and N 7  will be lit when abnormal breathing occurs. When urinary wetness exceeds a predetermined threshold, LED N 8  will be lit as well.  
     [0024] An audio alarm circuit, comprised of R 19 , N 9 , N 10  and BL, will operate to sound an alarm. Simultaneously, the radio transmission module will be activated to send a radio alarm signal. In a preferred embodiment of the present invention, a power supply is provided with “AA”sized batteries with a switch S 2  for turning on/off the system.  
     [0025] Thus, it is apparent that, based on the present invention, a reliable, convenient infant monitoring system can be provided that is capable of detecting both apnea and urinary wetness of an infant by using one integrated device, and then signal an alarm in a local site and to remote receivers when predetermined conditions occur. Consequently, the system can meet the requirement for monitoring the infant, greatly reducing workload of family members and nursing professionals. In addition, the system is convenient to use.  
     [0026] While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention. For example, while it is intended that the present invention be used to monitor infants, it is also applicable for others, such as the elderly, who are unable to care for themselves. Indeed, it is also conceivable that the present invention be used for monitoring animals, such as pets, whose owners desire such capability.