Patent Publication Number: US-2022233085-A1

Title: Portable blood pressure measuring device

Description:
TECHNICAL FIELD 
     The present disclosure relates to a portable blood pressure measuring device, and more particularly, to a portable blood pressure measuring device that measures a radial artery pressure wave and an ulnar artery pressure wave to provide a blood pressure value from which mutual interference is removed. 
     BACKGROUND 
     Recently, interest in health care has been increasing, and as the number of patients with high blood pressure and low blood pressure has been increasing, research on a wearable blood pressure measuring device that may easily check their own blood pressure has being actively conducted. 
     In particular, in order to improve portability of a blood pressure measuring device, a wearable blood pressure measuring device using a sensor to measure blood pressure has been developed. 
     In a case of measuring a pulse wave in the radial artery by using a pressure sensor, a conventional wearable blood pressure measuring device using the pressure sensor is also affected by a pulse wave generated in the ulnar artery, so that there is a problem in that a measured value thereof is inaccurate. 
     SUMMARY OF INVENTION 
     Technical Problem 
     The present disclosure is provided to solve the problems of the prior art described above, and an object of the present disclosure is to provide a portable blood pressure measuring device that calculates a more accurate blood pressure by disposing pressure sensors at positions corresponding to the radial artery and the ulnar artery, respectively, to measure the pressures, removing a mutual interference wavelength from the measured pressure, and using the pressures and the like. 
     In addition, another object of the present disclosure is to provide a portable blood pressure measuring device that may be used by being coupled to a smart watch or the like. 
     However, technical problems to be solved by the present embodiment are not limited to the technical problems as described above, and other technical problems may exist. 
     Solution to Problem 
     As technical means for solving the technical problems described above, according to a first aspect of the present disclosure, there is provided a portable blood pressure measuring device including: a body part in which a controller for calculating blood pressure information, a display for outputting blood pressure information, and a power supply are built; a wrist strap coupled to the body part; a fastening unit for fastening the wrist strap to the wrist; a first pressure sensor coupled to a first position of the wrist strap; and a second pressure sensor coupled to a second position of the wrist strap. The first pressure sensor is disposed to be adjacent to a position under which the user&#39;s radial artery passes, and the second pressure sensor is disposed to be adjacent to a position under which the user&#39;s ulnar artery passes. The controller calculates a blood pressure based on a first pressure and a second pressure measured by the first pressure sensor and the second pressure sensor, and an interference constant determined by the wrist strap. 
     Advantageous Effects 
     According to the above-described means for solving the problems of the present application, in a case where the portable blood pressure measuring device according to an embodiment of the present disclosure is used, the arterial pressure waves generated in the radial and ulnar arteries are respectively measured, and mutual interference is removed to measure the blood pressure with high-precision. 
     In addition, the portable blood pressure measuring device according to an embodiment of the present disclosure may be used by being coupled to a wearable device such as an existing smart watch or a healthcare band in addition to being used alone. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram illustrating a configuration of a portable blood pressure measuring device according to an embodiment of the present disclosure. 
         FIG. 2  is a sectional view illustrating a configuration of a portable blood pressure measuring device according to an embodiment of the present disclosure. 
         FIG. 3  is a sectional view for explaining a portable blood pressure measuring device having a pressing unit for each pressure sensor according to an embodiment of the present disclosure. 
         FIG. 4  is a sectional view illustrating a portable blood pressure measuring device used by being coupled to a smart watch or the like according to an embodiment of the present disclosure. 
         FIG. 5  is a sectional view illustrating a portable blood pressure measuring device using a roller instead of the pressing unit according to an embodiment of the present disclosure. 
         FIGS. 6A, 6B, 6C, and 6D  are diagrams illustrating ulnar artery pressure waves and radial artery pressure waves measured according to an embodiment of the present disclosure. 
     
    
    
     MODE OF DISCLOSURE 
     Hereinafter, embodiments of the present application will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art to which the present application pertains may easily implement them. However, the present application may be implemented in several different forms and is not limited to the embodiments described herein. In addition, in order to clearly explain the present application in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification. 
     Throughout the present specification, when a part is “connected” to another part, this includes not only a case of being “directly connected”, but also a case of being “electrically connected” to another element interposed therebetween. 
     Throughout the present specification, when a member is said to be located “on” another member, this includes not only a case where a member is in contact with another member but also a case where another member is present between the two members. 
     Throughout the present specification, a ‘wrist’ is a body part located between a hand and an arm, and may include a ‘wrist’ located between the wrist and the elbow. 
     Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the accompanying drawings. 
       FIG. 1  is a block diagram illustrating a configuration of a portable blood pressure measuring device according to an embodiment of the present disclosure. 
     As illustrated in the drawing, the portable blood pressure measuring device includes a body part  100  and a sensor  200 . The body part  100  includes a display  110 , a controller  120 , and a power supply  130 , and may further include a communication module  140 . The sensor  200  may include a first pressure sensor  210  and a second pressure sensor  220 . 
     The display  110  may be implemented with various types of display modules, such as a liquid crystal display, a reflective display, and an OLED display. The display  110  may display a blood pressure calculated by the controller  120  or other information. 
     The controller  120  may calculate an arterial blood pressure based on the pressures measured by the first pressure sensor  210  and the second pressure sensor  220 . An arterial blood pressure P a  is calculated by Equation 1 below. 
     
       
         
           
             
               
                 
                   
                     
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                   [ 
                   
                     Equation 
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     In Equation 1, P a  is a blood pressure of the radial artery, Pv is a blood pressure of the ulnar artery, S a  is a blood pressure value measured by the first pressure sensor  210 , S v  is a blood pressure value measured by the second pressure sensor  220 , and K is an interference constant determined by the wrist strap. 
     In a case where the first pressure sensor  210  measures the blood pressure, not only the blood pressure P a  of the radial artery but also the blood pressure Pv of the ulnar artery is transmitted through the wrist strap  500  and the pressing unit  300  surrounding the wrist. At this time, when the interference constant is defined as K, the first pressure sensor  210  measures the blood pressure by adding the value of the blood pressure Pv of the ulnar artery multiplied by the interference constant K to the blood pressure P a  of the radial artery. On the contrary, the second pressure sensor  220  measures the blood pressure by adding the value of the blood pressure P a  of the radial artery multiplied by the interference constant K to the blood pressure Pv of the ulnar artery. If this is arranged according to Equation  1 , the actual blood pressure P a  of the radial artery may be calculated. 
     The controller  120  controls the sensor  200  to measure the blood pressure when the blood pressure measurement is required, such as when blood pressure measurement request information is received or the blood pressure measurement is automatically set at regular intervals, and displays the measured information on the display  110 . 
     For example, the controller  120  may perform a series of processes in which the blood pressure may be measured in time unit, the measured blood pressure information may be displayed on the display  110 , an alarm may be generated in a case where a blood pressure outside a preset range is measured, and the corresponding information may be transmitted to a preset mobile phone or medical facility by using the communication module  140 . 
     The power supply  130  may be configured as a built-in type in the body part  100  or may be configured as an exchangeable replacing-type battery. 
     The communication module  140  may transmit and receive data such as blood pressure information measured by communication between the body part  100  and various external devices (servers or terminals) in a set communication format. In addition, the communication module  140  may receive update information such as a program related to the blood pressure measurement, from an external device and transmit the information to the controller  120 . 
     The sensor  200  for measuring the blood pressure may include the first pressure sensor  210  and the second pressure sensor  220 . 
     The first pressure sensor  210  and the second pressure sensor  220  included in the sensor  200  are adjacent to positions under which the radial artery A and the ulnar artery B pass, respectively, and are disposed to be in close contact with the wrist. 
     At this time, the first pressure sensor  210  and the second pressure sensor  220  may be a strain gauge-based semiconductor thin film sensor, a capacitive thin film sensor for detecting a capacity change according to a pressure, a piezoresistive sensor using a piezo resistance effect, or other various pressure sensors. 
     Here, the strain gauge-based semiconductor thin film sensor has an advantage that only the resistance change is controlled by arranging four resistors on a diaphragm in a Wheatstone bridge form. The capacitive thin film sensor has advantages that it has strong heat resistance and corrosion resistance, and high-precision measurement is possible when measuring the pressure. The piezoresistive sensor has advantages that high sensitivity, excellent linearity, and reproducibility are excellent when measuring the pressure, and it is easy to mass-produce. 
     In addition, the first pressure sensor  210  and the second pressure sensor  220  may each include a plurality of sensors arranged in an array form. 
     Since the first pressure sensor  210  and the second pressure sensor  220  each measure pressure using the plurality of sensors, at least one of a maximum value, a minimum value, a maximum frequency value, and an average value among the pressures sensed by the sensors included in each of the pressure sensors  210  and  220 , when the blood pressure is calculated, may be used by being specified as the first pressure and the second pressure, respectively. 
       FIG. 2  is a sectional view illustrating a configuration of a portable blood pressure measuring device according to an embodiment of the present disclosure. 
     In the portable blood pressure measuring device, the body part  100 , the first pressure sensor  210 , the second pressure sensor  220 , the pressing unit  300 , and the fastening unit  400  may be located on the wrist strap  500 . 
     In the body part  100 , the display  110  is located outside the body part  100  furthest from the wrist when being worn on the wrist so that the user may easily recognize the display  110 . The controller  120  and the power supply  130  are located inside the display  110  and are not limited to a specific position. 
     The first pressure sensor  210  is disposed adjacent to a position under which the user&#39;s radial artery A passes, on the wrist strap  500 , and the second pressure sensor  220  is disposed adjacent to a position under which the user&#39;s ulnar artery B passes, on the wrist strap  500 . 
     The body part  100  may be located below the first pressure sensor  210  and the second pressure sensor  220 , and may be electrically connected to the first pressure sensor  210  and the second pressure sensor  220 . 
     The pressing unit  300  may be disposed between the first pressure sensor  210  and the second pressure sensor  220 , and the wrist strap  500  to adjust a degree of contact between the first pressure sensor  210  and the second pressure sensor  220 , and the wrist. The pressing unit  300  may be an air bag, an actuator, a thermal expansion device, a deformable alloy device, or the like. 
     The air bag may be operated by receiving air supplied by a valve or the like so that the sensor  200  is in close contact with the wrist, and the actuator may be operated by using electricity, hydraulic pressure, compressed air, or the like so that the sensor  200  is in close contact with the wrist. The degree of contact of the wrist strap  500  and the sensor  200  may be adjusted by using the thermal expansion device having a large coefficient of thermal expansion or using the deformable alloy device. 
     The fastening units  400  are located at both ends of the wrist strap  500  to fasten one end and the other end of the wrist strap  500 , and the degree of contact of the wrist strap  500  may be adjusted in consideration of the thickness of the wrist. In the configuration of  FIG. 2 , respective pressure sensors are located adjacent to the radial artery A and the ulnar artery B, and the body part  100  is located at the lower portion thereof, so the body part  100  is located opposite to the back of the user&#39;s hand. 
       FIG. 3  is a sectional view illustrating a portable blood pressure measuring device having a pressing unit for each pressure sensor according to an embodiment of the present disclosure. 
     Instead of the pressing unit  300  illustrated in  FIG. 2 , a first air bag  310  and a second air bag  320  may be installed between the wrist strap  500  and the wrist to serve as the pressing unit. The first air bag may be disposed between the wrist strap  500  and the first pressure sensor  210  disposed adjacent to the position under which the radial artery A passes, and the second air bag  320  may be disposed between the wrist strap  500  and second pressure sensor  220  disposed adjacent to the position under which the ulnar artery B passes. 
       FIG. 4  is a sectional view illustrating a portable blood pressure measuring device used by being coupled to a smart watch or the like according to an embodiment of the present disclosure. 
     The portable blood pressure measuring device may be used by being coupled to a smart watch module  600 . Both ends of the wrist strap  500  may have first fastening means  410  and second fastening means  420  coupled to the smart watch module  600  so as to couple to a first connection portion  610  and a second connection portion  620  of the smart watch module  600 . A length of the wrist strap  500  may be adjusted by using the first fastening means  410  and the second fastening means  420  to adjust the degree of contact with the wrist. 
     In order to fasten the smart watch module  600  to the wrist strap  500 , a separate device including the first connection portion  610  and the second connection portion  620  may be coupled or a smart watch case including a connection portion may be used, but a method of coupling the smart watch module  600  is not limited thereto. 
     The first pressure sensor  210  may include the first air bag  310  and the first pressure sensor provided in the first air bag  310 , and the second pressure sensor  220  may include the second air bag  320  and a second pressure sensor provided in the second air bag  320 . 
       FIG. 5  is a sectional view illustrating a portable blood pressure measuring device using a roller instead of a pressing unit according to an embodiment of the present disclosure. 
     In the portable blood pressure measuring device, a wrist strap  500  including a roller  700  instead of the pressing unit  300  may be used. When the roller  700  rotates, the length of the wrist strap  500  is adjusted, so that when the blood pressure is measured, the roller may be rotated to tighten the wrist strap  500  to be in close contact with the wrist. 
       FIG. 6  is a diagram illustrating the ulnar artery pressure waves and the radial artery pressure waves measured according to an embodiment of the present disclosure. That is,  FIG. 6A  is a diagram for explaining systolic and diastolic blood pressure,  FIG. 6B  is a diagram illustrating a blood pressure waveform generated in the radial artery,  FIG. 6C  is a diagram illustrating a blood pressure waveform generated in the ulnar artery, and  FIG. 6D  is a diagram illustrating results of measuring the radial artery waveform and the ulnar artery waveform together. 
     In a case where the blood pressure is measured by using the sensor  200  in the portable blood pressure measuring device, an arterial pressure wave is amplified by a mutual interference signal between the radial and ulnar arterial pressure waves transmitted by a cuff strip surrounding the wrist, and the amplified blood pressure may be measured as illustrated in  FIG. 6 d   . In the present disclosure, since the blood pressure is measured at two places of the first pressure sensor  210  and the second pressure sensor  220 , even if the signal of  FIG. 6 d    is measured in the first pressure sensor  210 , the waveform of  FIG. 6 c   may be removed in consideration of the measured value in the second pressure sensor  220  and the interference constant, and the blood pressure may be measured based on the waveform of  FIG. 6 b   . In this case, SYSTOLIC is the systolic blood pressure, and DIASTOLIC is the diastolic blood pressure. 
     An embodiment of the present disclosure may also be implemented in a form of a recording medium including instructions executable by a computer, such as a program module executed by a computer. Computer-readable media may be any available media that may be accessed by a computer and includes both volatile and nonvolatile media, removable and non-removable media. In addition, the computer-readable media may include computer storage media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules, or other data. 
     Although the method and the system of the present disclosure have been described with reference to specific embodiments, some or all of their configuration elements or operations may be implemented by using a computer system having a general purpose hardware architecture. 
     The foregoing description of the present application is for illustration, and those of ordinary skill in the art to which the present application pertains will understand that it may be easily modified into other specific forms without changing the technical spirit or essential features of the present application. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each configuration element described as a single type may be implemented in a dispersed form, and likewise configuration elements described as distributed may be implemented in a combined form. 
     The scope of the present application is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present application. 
     
       
         
           
               
             
               
                   
               
             
            
               
                 10: blood pressure measuring device 
               
               
                 100: body part, 110: display 
               
               
                 120: controller, 130: power supply 
               
               
                 140: communication module 
               
               
                 200: sensor 
               
               
                 210: first pressure sensor, 220: second pressure sensor 
               
               
                 300: pressing unit 
               
               
                 310: first air bag, 320: second air bag 
               
               
                 400: fastening unit 
               
               
                 410: first fastening means, 420: second fastening means 
               
               
                 500: wrist strap 
               
               
                 600: smart watch module 
               
               
                 610: first connection portion, 620: second connection portion 
               
               
                 700: roller