Biological information measuring device and acoustic communication system

Abstract

To suppress an increase in the number of parts for sound wave transmission in a biological information measuring device having a function to transmit acquired biological information as a sound wave.SOLUTION: A biological information measuring device in the present invention includes: a piezoelectric pump 32 capable of supplying fluid for compressing a part to be measured; pressure control units 110 and 320 for controlling pressure for the part to be measured by applying a first driving voltage V1 within a predetermined normal range to the piezoelectric pump 32, and turning on or off a fluid supply operation of the piezoelectric pump 32; biological information measuring units 110, 31, 310, and 311 for acquiring biological information from the part to be measured in a state where the pressure to the part to be measured is controlled; and sound wave communication control units 110 and 320 for executing control to apply a second driving voltage V2 within a predetermined specific range to the piezoelectric pump 32, and cause the piezoelectric pump 32 to generate a sound wave or to stop generating the sound wave.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a biological information measuring device, more particularly to a biological information measuring device having a function of transmitting acquired biological information as sound waves (including ultrasound). The present invention also relates to an acoustic wave communication system including the biological information measuring device and a device having a function of receiving the sound waves. [Background technology]

[0002] As a conventional biological information measurement device of this type, for example, Patent Document 1 (JP 2020-160589 A) discloses a measuring instrument equipped with an output means including an oscillator capable of generating ultrasound. The measuring instrument is disclosed to function as one of a weight scale, a body composition monitor, a blood pressure monitor, a pulse monitor, a thermometer, and an activity monitor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-160589 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above-mentioned measuring instruments are equipped with a speaker and peripheral circuits to drive the speaker as output means, which increases the number of components, resulting in higher costs and larger sizes of the measuring instruments.

[0005] Therefore, an object of the present invention is to provide a biological information measuring device having a function of transmitting acquired biological information as sound waves, which can suppress an increase in the number of parts required for sound wave transmission.An object of the present invention is also to provide an acoustic wave communication system including the biological information measuring device and a device having a function of receiving sound waves. [Means for solving the problem]

[0006] In order to solve the above problems, the biological information measurement device disclosed herein comprises: A biological information measurement device for measuring biological information of a measurement site, a piezoelectric pump capable of supplying fluid to compress the measurement site; a pressure control unit that applies a first drive voltage within a predetermined normal range to the piezoelectric pump to turn on a fluid supply operation of the piezoelectric pump, or removes the first drive voltage to turn off a fluid supply operation of the piezoelectric pump, thereby controlling the pressure on the measurement site; a biological information measurement unit that acquires biological information from the measurement site while the pressure on the measurement site is controlled; an acoustic wave communication control unit that applies a second drive voltage within a predetermined range to the piezoelectric pump to cause the piezoelectric pump to generate acoustic waves, or removes the second drive voltage to stop the piezoelectric pump from generating acoustic waves; The present invention is characterized by the following features.

[0007] Here, "biological information" may include, for example, blood pressure, electrocardiogram, pulse, body temperature, activity level, and the like.

[0008] A "piezoelectric pump" is a pump that compresses and discharges fluid by vibrating a diaphragm using a piezoelectric element. During operation, a driving voltage (high frequency voltage) of typically several tens of kHz is applied to the piezoelectric element.

[0009] The "predetermined normal range" of the first drive voltage typically refers to a voltage range and a frequency range that are predetermined in the product specifications of the piezoelectric pump.

[0010] Furthermore, the "predetermined specific range" of the second drive voltage typically refers to a voltage range below the normal range and a frequency range outside the normal range, but may also be a range that overlaps with the normal range.

[0011] Furthermore, the term "sound waves" is used in a broad sense in this specification and includes not only audible sounds but also ultrasonic waves.

[0012] In the disclosed biological information measuring device, the pressure control unit applies a first drive voltage within a predetermined normal range to the piezoelectric pump to turn on the fluid supply operation of the piezoelectric pump, or removes the first drive voltage to turn off the fluid supply operation of the piezoelectric pump, thereby controlling the pressure at the measurement site. The biological information measuring unit acquires biological information from the measurement site while the pressure at the measurement site is controlled. The sonic communication control unit applies a second drive voltage within a predetermined specific range to the piezoelectric pump to cause the piezoelectric pump to generate sound waves, or removes the second drive voltage to stop the piezoelectric pump from generating sound waves. This causes sound waves to be transmitted from the piezoelectric pump. In this manner, in this biological information measuring device, the piezoelectric pump, which is originally provided for pressure control by the pressure control unit, also serves as a sound generator. This prevents an increase in the number of parts required for sound wave transmission. As a result, the biological information measuring device can be configured at low cost and in a compact size.

[0013] In one embodiment, the biological information measuring device includes: When the biological information measurement unit acquires biological information from the measurement site, the acquisition of the biological information is used as a trigger for the pressure control unit to remove the first drive voltage and turn off the fluid supply operation of the piezoelectric pump, and the acoustic wave communication control unit applies the second drive voltage to the piezoelectric pump, thereby controlling the piezoelectric pump to generate acoustic waves representing the biological information. It is characterized by:

[0014] In this embodiment of the biological information measuring device, when the biological information measuring unit acquires biological information from the measurement site, the acquisition of the biological information triggers the pressure control unit to remove the first drive voltage and turn off the fluid supply operation of the piezoelectric pump. In this state, the ultrasonic communication control unit applies the second drive voltage to the piezoelectric pump, causing the piezoelectric pump to generate sound waves representing the biological information. As a result, sound waves representing the biological information are transmitted from the piezoelectric pump as the biological information is acquired. In this case, the application of the first drive voltage to the piezoelectric pump by the pressure control unit and the application of the second drive voltage to the piezoelectric pump by the ultrasonic communication control unit are separated in time and therefore do not interfere with each other.

[0015] In one embodiment, the biological information measuring device includes: a storage unit that stores the biological information acquired by the biological information measurement unit; an operation unit for inputting instructions from a user; When the fluid supply operation of the piezoelectric pump is turned off, an instruction is input by the operation unit, which triggers the sonic communication control unit to control the piezoelectric pump to generate a sound wave representing the biological information stored in the storage unit. It is characterized by:

[0016] In one embodiment of the biological information measuring device, a storage unit stores biological information acquired by the biological information measuring unit. When the fluid supply operation of the piezoelectric pump is turned off, an instruction input via the operation unit triggers the sonic communication control unit to control the piezoelectric pump to generate sound waves representing the biological information stored in the storage unit. As a result, the sound waves representing the biological information stored in the storage unit are transmitted from the piezoelectric pump at a timing desired by the user other than during measurement. In this case, because the fluid supply operation of the piezoelectric pump is turned off, the application of the first drive voltage to the piezoelectric pump by the pressure control unit and the application of the second drive voltage to the piezoelectric pump by the sonic communication control unit do not interfere with each other.

[0017] In one embodiment, the biological information measuring device includes: The sound wave representing the biological information is a modulated wave obtained by amplitude shift modulation of a carrier wave having a predetermined amplitude and frequency with a signal representing the biological information. It is characterized by:

[0018] Here, "Amplitude Shift Keying (ASK)" is a digital modulation method that transmits data by changing the amplitude of a carrier wave in accordance with the bit sequence ("1" and "0") of the transmitted data.

[0019] In the biological information measuring device of this embodiment, the sound wave representing the biological information is a modulated wave obtained by amplitude-shift keying a carrier wave having a predetermined amplitude and frequency with a signal representing the biological information. This amplitude-shift keying technique allows the generation of a modulated wave with a simpler configuration (components) than other digital modulation methods (such as frequency shift keying (FSK) and phase shift keying (PSK)). Therefore, this biological information measuring device can be configured at even lower cost and in a smaller size.

[0020] In one embodiment, the biological information measuring device includes: a cuff for compressing the measurement site; a pressure sensor for detecting the pressure in the cuff; a drain valve for draining the fluid from the cuff; Equipped with the pressure control unit controls the pressure at the measurement site by supplying fluid to the cuff to pressurize it while applying the first drive voltage to turn on the fluid supply operation of the piezoelectric pump, and / or by discharging the fluid from the cuff via the discharge valve to reduce the pressure while removing the first drive voltage to turn off the fluid supply operation of the piezoelectric pump, During the process of increasing the pressure of the cuff or the process of decreasing the pressure of the cuff by the pressure control unit, the biological information measurement unit calculates a blood pressure value based on pulse wave information representing the pulse wave at the measurement site included in the output of the pressure sensor. It is characterized by:

[0021] In the biological information measurement device of this embodiment, for example, during a process in which the pressure control unit increases the pressure of the cuff (i.e., while supplying fluid to the cuff to increase the pressure with the first drive voltage applied and the fluid supply operation of the piezoelectric pump turned on), the biological information measurement unit calculates a blood pressure value, for example, by an oscillometric method, based on pulse wave information representing the pulse wave at the measurement site and included in the output of the pressure sensor. Alternatively, during a process in which the pressure control unit decreases the pressure of the cuff (i.e., while removing the first drive voltage and turning off the fluid supply operation of the piezoelectric pump to decrease the pressure with the fluid being discharged from the cuff via the discharge valve), the biological information measurement unit calculates a blood pressure value, for example, by an oscillometric method, based on pulse wave information representing the pulse wave at the measurement site and included in the output of the pressure sensor. In this way, a blood pressure value can be acquired as the biological information.

[0022] In one embodiment, the blood pressure monitor During the pressurization process, the biological information measurement unit calculates a blood pressure value based on the pulse wave information included in the output of the pressure sensor, When the blood pressure value is calculated, the pressure control unit removes the first drive voltage to turn off the fluid supply operation of the piezoelectric pump, and the acoustic wave communication control unit applies the second drive voltage to the piezoelectric pump to perform control to generate an acoustic wave representing the blood pressure value. It is characterized by:

[0023] In the biological information measurement device of this embodiment, during the pressurization process, the biological information measurement unit calculates a blood pressure value based on the pulse wave information included in the output of the pressure sensor. The calculation of the blood pressure value triggers the pressure control unit to remove the first drive voltage and turn off the fluid supply operation of the piezoelectric pump. Then, the ultrasonic communication control unit applies the second drive voltage to the piezoelectric pump, causing the piezoelectric pump to generate sound waves representing the blood pressure value. As a result, as the blood pressure value is acquired during the pressurization process, sound waves representing the blood pressure value are transmitted from the piezoelectric pump. In this manner, the application of the first drive voltage to the piezoelectric pump by the pressure control unit and the application of the second drive voltage to the piezoelectric pump by the ultrasonic communication control unit are separated in time and therefore do not interfere with each other.

[0024] In one embodiment, the blood pressure monitor After the pressure of the cuff is increased to temporarily block blood flow to the measurement site, the pressure control unit removes the first drive voltage to turn off the fluid supply operation of the piezoelectric pump, and in this state, during the depressurization process of depressurizing the cuff, the biological information measurement unit attempts to calculate a blood pressure value based on the pulse wave information included in the output of the pressure sensor, and The sonic wave communication control unit applies the second drive voltage to the piezoelectric pump to perform control to generate a sonic wave representing the pulse wave information. It is characterized by:

[0025] In the biological information measurement device of this embodiment, after the cuff is pressurized to temporarily block blood flow to the measurement site, during the depressurization process (i.e., while the cuff pressure is reduced with the pressure control unit removing the first drive voltage and turning off the fluid supply operation of the piezoelectric pump), the biological information measurement unit attempts to calculate a blood pressure value based on the pulse wave information included in the output of the pressure sensor. At the same time, the ultrasonic communication control unit applies the second drive voltage to the piezoelectric pump, controlling the piezoelectric pump to generate sound waves representing the pulse wave information. This allows the ultrasonic communication control unit to transmit sound waves representing the pulse wave information in real time while the biological information measurement unit attempts to calculate the blood pressure value during the depressurization process. In this case, because the fluid supply operation of the piezoelectric pump is turned off during the depressurization process, the application of the first drive voltage to the piezoelectric pump by the pressure control unit and the application of the second drive voltage to the piezoelectric pump by the ultrasonic communication control unit do not interfere with each other.

[0026] In one embodiment, the blood pressure monitor The discharge valve is a passive valve that is integrally formed with the piezoelectric pump, and is configured to close when the fluid supply operation of the piezoelectric pump is turned on, and to open when the fluid supply operation of the piezoelectric pump is turned off. It is characterized by:

[0027] In this embodiment of the biological information measuring device, the discharge valve is a passive valve integrally formed with the piezoelectric pump, which closes when the piezoelectric pump is turned on to supply fluid and opens when the piezoelectric pump is turned off to supply fluid. This eliminates the need to provide the discharge valve separately from the piezoelectric pump, reducing the number of components. As a result, the biological information measuring device can be constructed at even lower cost and in a smaller size.

[0028] In another aspect, the acoustic communication system of the present disclosure comprises: A sonic wave communication system that uses sonic waves to communicate, the biological information measuring device; a device having a function of receiving sound waves from the piezoelectric pump; An acoustic wave communication system comprising:

[0029] According to the disclosed ultrasonic communication system, ultrasonic waves are transmitted from the piezoelectric pump of the biological information measuring device. The device has a function of receiving the ultrasonic waves from the piezoelectric pump. Therefore, communication via ultrasonic waves is possible between the biological information measuring device and the device. [Effects of the Invention]

[0030] As is clear from the above, the disclosed biological information measuring device can suppress an increase in the number of parts required for transmitting sound waves. Also, the disclosed ultrasonic communication system enables communication between the biological information measuring device and the device via sound waves. [Brief explanation of the drawings]

[0031] [Figure 1] 1 is a diagram showing a block configuration of a blood pressure monitor as one embodiment of a biological information measuring device of the present invention. [Figure 2] 1 is a diagram showing a block configuration of an acoustic wave communication system (including the blood pressure monitor) according to an embodiment of the present invention. [Figure 3] FIG. 1 is a diagram showing the configuration of a test circuit for checking the operation of a commercially available piezoelectric pump itself. [Figure 4] Figure 4(A) shows the application of a driving voltage V to the piezoelectric pump using the test circuit of Figure 3, with a frequency f = 23.0 kHz and a peak-to-peak amplitude Va varied from 3 V to 15 V. Figure 4(B) shows the pressure P observed at the fluid outlet of the piezoelectric pump when the amplitude Va of the driving voltage V is varied as shown in Figure 4(A). Figures 4(C) and 4(D) show the state of Figures 4(A) and 4(B), respectively, with the horizontal axis (time axis) enlarged. [Figure 5]Figure 5(A) shows the application of a driving voltage V to the piezoelectric pump using the test circuit of Figure 3, with a frequency f = 17.0 kHz and a peak-to-peak amplitude Va varied from 3 V to 15 V. Figure 5(B) shows the pressure P observed at the fluid outlet of the piezoelectric pump when the amplitude Va of the driving voltage V is varied as shown in Figure 5(A). Figures 5(C) and 5(D) show the state of Figures 5(A) and 5(B), respectively, with the horizontal axis (time axis) enlarged. [Figure 6] Fig. 6(A) is a diagram showing a process flow in which the blood pressure monitor measures the blood pressure at the measurement site during the cuff inflation process and transmits the acquired blood pressure value data as sound waves. Fig. 6(B) is a diagram showing a process flow in which the smartphone receives the sound waves transmitted from the blood pressure monitor, demodulates the data represented by the received sound waves, and displays the data. [Figure 7] FIG. 10 is a diagram showing a process flow in which the blood pressure monitor measures blood pressure at a measurement site during the cuff decompression process, and transmits data acquired during blood pressure calculation and calculated blood pressure value data as sound waves. [Figure 8] 1A to 1C are diagrams illustrating waveforms or modes of sound waves, demodulated waves, etc. transmitted / received by the sound wave communication system (including the sphygmomanometer). DETAILED DESCRIPTION OF THE INVENTION

[0032] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. (Blood pressure monitor configuration) 1 shows a block diagram of a blood pressure monitor 100 as one embodiment of a biological information measuring device of the present invention. This blood pressure monitor 100 mainly comprises a blood pressure measurement cuff 20 that is attached around a measurement site such as the upper arm or wrist, and a main body 10 that is fluidly connected to the cuff 20 via an air pipe 38. The measurement site is typically the upper arm, but is not limited to the upper arm and may be an upper limb other than the upper arm, such as the wrist, or a lower limb, such as the ankle.

[0033] The cuff 20 is a typical one, and includes a long, thin, bag-like band 21 and a fluid bag 22 contained within the band 21.

[0034] The main body 10 is equipped with a control unit 110, a display 50, an operation unit 52, a memory 51 as a storage unit, a power supply unit 53, a pressure sensor 31, a filter 310, an amplifier 311, a commercially available piezoelectric pump 32, a pump drive circuit 320, a discharge valve 33, and a valve drive circuit 330. In this example, an air pipe 38a connected to the pressure sensor 31, an air pipe 38b connected to the piezoelectric pump 32, and an air pipe 38c connected to the discharge valve 33 join together to form a single air pipe 38 that is connected to the fluid bag 22 in the cuff 20 so as to be able to fluidly communicate with the fluid bag 22. Hereinafter, the air pipes 38a, 38b, and 38c will be collectively referred to as the air pipe 38.

[0035] In this example, the display 50 is made up of an LCD (Liquid Crystal Display) and displays predetermined information in accordance with a control signal from the control unit 110. In this example, the display displays the systolic blood pressure SYS (Systolic Blood Pressure, unit: mmHg), the diastolic blood pressure DIA (Diastolic Blood Pressure, unit: mmHg), and the pulse rate PLS (unit: beats / min). The display 50 may be made up of an organic EL (Electro Luminescence) display or may include an LED (Light Emitting Diode).

[0036] In this example, the operation unit 52 has a measurement switch 52A for receiving an instruction to start / stop blood pressure measurement, a memory switch 52B for calling up past measurement results, and a communication switch 52C for receiving an instruction to transmit blood pressure value data to the outside. These switches 52A, 52B, and 52C input operation signals to the CPU 110 in response to instructions from a user (in this example, the subject).

[0037] Memory 51 stores data of a program for controlling sphygmomanometer 100, setting data for setting various functions of sphygmomanometer 100, and data of blood pressure measurement results. Memory 51 is also used as a work memory when a program is executed.

[0038] The control unit 110 includes a CPU (Central Processing Unit) as a processor and controls the overall operation of the sphygmomanometer 100. Specifically, the control unit 110 functions as a pressure control unit in accordance with a program for controlling the sphygmomanometer 100 stored in the memory 51, and controls the driving of the piezoelectric pump 32 and the discharge valve 33 as pressure devices in response to an operation signal from the operation unit 52. The control unit 110 also functions as a biological information measurement unit, and in this example, calculates a blood pressure value using a known oscillometric method based on the output of the pressure sensor 31, and controls the display 50 and the memory 51. A specific method of blood pressure measurement will be described later. The control unit 110 also functions as an ultrasonic communication control unit. A specific method of ultrasonic communication will be described later.

[0039] In this example, pressure sensor 31 is a piezoresistive pressure sensor that outputs an electrical signal representing the pressure of fluid bag 22 contained in cuff 20 (referred to as "cuff pressure Pc") through air piping 38. Filter 310 is a high-pass filter that receives the electrical signal from pressure sensor 31 and outputs a signal (pulse wave information) representing the fluctuation component due to the pulse wave contained in cuff pressure Pc. Amplifier 311 amplifies the signal output by filter 310 and inputs it to control unit 110 as pulse wave information. This pulse wave information is used to calculate blood pressure.

[0040] The piezoelectric pump 32 is a commercially available product that uses a piezoelectric element to vibrate a diaphragm to compress and discharge fluid. The piezoelectric pump 32 is driven by a drive voltage V from a pump drive circuit 320 based on a control signal provided by the control unit 110. The drive voltage V is determined by two factors: peak-to-peak amplitude Va and frequency f. Specifically, the fluid supply operation of the piezoelectric pump 32 is turned on when a drive voltage V (referred to as a "first drive voltage V1") within a predetermined normal range (in this example, the voltage range and frequency range predetermined in the product specifications of the piezoelectric pump 32) is applied. Air is then supplied to the fluid bag 22 contained in the cuff 20 through the air pipe 38. This increases the pressure in the fluid bag 22 (cuff pressure Pc). When the first drive voltage V1 is removed, the fluid supply operation of the piezoelectric pump 32 is turned off. Here, the normal range refers to a voltage range (in this example, a peak-to-peak amplitude Va range from 15 V to 38 V) and a frequency range (in this example, a frequency f range from 21.5 kHz to 24.0 kHz) predetermined in the product specifications of the piezoelectric pump 32. Furthermore, when a drive voltage V (referred to as a "second drive voltage V2") within a predetermined specific range that includes the normal range is applied to the piezoelectric pump 32, the piezoelectric pump 32 generates sound waves (ultrasound waves in this example). Here, the second drive voltage V2 is set to a voltage range below the normal range and a frequency range outside the normal range. When the second drive voltage V2 is removed, the piezoelectric pump 32 stops generating sound waves. The operation of the piezoelectric pump 32 will be described in more detail below.

[0041] In this example, the discharge valve 33 is a normally open electromagnetic control valve, and is driven to open and close by a valve drive circuit 330 based on a control signal given from the control unit 110. The discharge valve 33 is used to discharge air from the fluid bag 22 through an air pipe 38, or to seal air in the fluid bag 22 to control the cuff pressure.

[0042] The power supply unit 53 supplies power to the control unit 110, the display 50, the memory 51, the pressure sensor 31, the piezoelectric pump 32, the discharge valve 33, and other components within the main body 10.

[0043] (Configuration of acoustic communication system) Fig. 2 shows a block diagram of an acoustic wave communication system 800 including the above-described sphygmomanometer 100 according to an embodiment of the present invention. In addition to the above-described sphygmomanometer 100, the acoustic wave communication system 800 includes a smartphone 500 as a device having a function of receiving acoustic waves. In Fig. 2, some components of the main body 10 of the sphygmomanometer 100 are omitted for simplicity.

[0044] Smartphone 500 includes main body 500M and, mounted on main body 500M, control unit 510, memory 520, operation unit 530, display 540, microphone 560, and communication unit 590. Smartphone 500 is a commercially available smartphone on which application software (computer program) is installed to perform the processing described below (for example, demodulation of sound waves).

[0045] Control unit 510 includes a CPU and its auxiliary circuits, controls each unit of smartphone 500, and executes the processes described below in accordance with the programs and data stored in memory 520. That is, control unit 510 processes data input from operation unit 530 and microphone 560, and stores the processed data in memory 520, displays it on display 540, and outputs it from communication unit 590.

[0046] Memory 520 includes RAM (Random Access Memory) used as a working area required for executing programs in control unit 510, and ROM (Read Only Memory) for storing basic programs to be executed by control unit 510. In addition, a semiconductor memory (memory card, SSD (Solid State Drive)) or the like may be used as a storage medium of an auxiliary storage device for supplementing the storage area of ​​memory 520.

[0047] In this example, operation unit 530 includes a touchpad (not shown) superimposed on the display screen of display device 540, and inputs an operation signal indicating an operation by a user (a subject in this example) to control unit 510.

[0048] Display unit 540 is controlled by control unit 510 to display a predetermined image on a display screen (for example, an LCD or EL display, etc.) In this example, display unit 540 and touch pad 531 form a known touch panel.

[0049] The microphone 560 receives sound waves coming from outside the main body 500M and outputs an electrical signal representing the received sound waves. The electrical signal (analog signal) output by the microphone 560 is converted into a digital signal by an AD converter (not shown) and input to the control unit 510. This allows the smartphone 500 to function as a device having the function of receiving sound waves from the piezoelectric pump 32.

[0050] Communication unit 590 transmits information from control unit 510 to another device (for example, a server not shown) via network 900. It also receives information from other devices via network 900 and passes it to control unit 510.

[0051] (Piezoelectric pump operation) 3 shows the configuration of a test circuit 700 for verifying the operation of the piezoelectric pump 32 itself. This test circuit 700 includes a function generator 701 for applying a drive voltage V (defined by two elements, peak-to-peak amplitude Va and frequency f) to the piezoelectric pump 32, a pressure meter 702 for measuring the pressure P at the fluid outlet of the piezoelectric pump 32, and an oscilloscope 703 having probes PRB1 and PRB2. The drive voltage V applied to the piezoelectric pump 32 by the function generator 701 is input to channel CH1 of the oscilloscope 703 via probe PRB1. The pressure at the fluid outlet of the piezoelectric pump 32 is input from the pressure meter 702 to channel CH2 of the oscilloscope 703 via probe PRB2.

[0052] FIG. 4A shows the results observed on channel CH1 of the oscilloscope 703 when the function generator 701 of the test circuit 700 in FIG. 3 applied a driving voltage V to the piezoelectric pump 32 at a normal frequency of f=23.0 kHz with a peak-to-peak amplitude Va varying in steps from 3 V to 15 V. FIG. 4B shows the results observed on channel CH2 of the oscilloscope 703 when the amplitude Va of the driving voltage V was varied as shown in FIG. 4A. In this example, it can be seen that the fluid supply operation of the piezoelectric pump 32 was turned on and the pressure P began to increase at time t1, when Va1 was increased to 9 V. In other words, when Va was less than 9 V (e.g., when Va was in the range of 3 V to 6 V), the fluid supply operation of the piezoelectric pump 32 remained off even at a normal frequency of f=23 kHz. 4(C) and 4(D) show the state of FIG. 4(A) and FIG. 4(B) around time t1 (just before Va=9 V) with the horizontal axis (time axis) enlarged. As can be seen from FIG. 4(C), the period T1 of the drive voltage V corresponds to the frequency f=23.0 kHz.

[0053] FIG. 5(A) shows the results observed on channel CH1 of oscilloscope 703 when the function generator 701 of the test circuit 700 of FIG. 3 applies a driving voltage V to the piezoelectric pump 32 at a frequency f=17.0 kHz outside the normal range, while varying the peak-to-peak amplitude Va in steps from 3 V to 15 V. FIG. 5(B) shows the results observed on channel CH2 of oscilloscope 703, illustrating the pressure P observed at the fluid outlet of the piezoelectric pump 32 when the amplitude Va of the driving voltage V is varied as shown in FIG. 5(A). In this example, it can be seen that even when Va is increased from 3 V to 15 V, the fluid supply operation of the piezoelectric pump 32 remains off, and the pressure P remains zero. In other words, at a frequency f=17.0 kHz outside the normal range, the fluid supply operation of the piezoelectric pump 32 remains off even when the peak-to-peak amplitude Va increases to 15 V (the lower limit of the normal voltage range). Here, it was confirmed, for example, by using the smartphone (microphone 560) shown in FIG. 2, that the piezoelectric pump 32 generates sound waves (in this example, ultrasonic waves) with a frequency f (=17.0 kHz) corresponding to the drive voltage V, even when the fluid supply operation is off. Note that FIGS. 5(C) and 5(D) respectively show the state around time t2 (when Va=12 V) in FIGS. 5(A) and 5(B) with the horizontal axis (time axis) enlarged. As can be seen from FIG. 5(C), the period T2 of the drive voltage V corresponds to the frequency f=17.0 kHz.

[0054] From observations of the operation of the piezoelectric pump 32 itself, including the above, the inventors have confirmed the following facts. That is, as described above, when a first drive voltage V1 within a predetermined normal range (in this example, the voltage range and frequency range predetermined in the product specifications of the piezoelectric pump 32) is applied to the piezoelectric pump 32, the fluid supply operation is turned on. When the first drive voltage V1 is removed, the fluid supply operation of the piezoelectric pump 32 is turned off. Here, the above-mentioned normal range refers to the voltage range (in this example, the peak-to-peak amplitude Va range from 15 V to 38 V) and frequency range (in this example, the frequency f range from 21.5 kHz to 24.0 kHz) predetermined in the product specifications of the piezoelectric pump 32, as shown in Table 1 below. In this example, when the control unit 110 functions as a pressure control unit to turn on the fluid supply operation of the piezoelectric pump 32, the frequency f of the first drive voltage V1 is fixed to 23.0 kHz, and the peak-to-peak amplitude Va is variably set within a range from 15 V to 38 V depending on the amount of fluid supply required to pressurize the cuff 20.

[0055] Furthermore, the piezoelectric pump 32 generates sound waves when a drive voltage V (referred to as a second drive voltage V2) within a predetermined specific range, including the normal range, is applied. When the second drive voltage V2 is removed, the piezoelectric pump 32 stops generating sound waves. However, when using the piezoelectric pump 32 for sonic communication, it is convenient to have the piezoelectric pump 32 only generate sound waves while turning off the fluid supply operation of the piezoelectric pump 32. In other words, when performing sonic communication, there is no risk of unnecessarily pressurizing the cuff 20 (fluid bag 22), constricting the subject's arm, and causing blood congestion. Therefore, as shown in Table 1 below, in this example, the specific range is set as a range in which the peak-to-peak amplitude Va is less than 15 V and the frequency f is less than 21.5 kHz or greater than 24.0 kHz. In this example, when the control unit 110 functions as a sonic communication control unit to cause the piezoelectric pump 32 to generate sound waves, the frequency f of the second drive voltage V2 is fixed to 17.0 kHz, and the peak-to-peak amplitude Va is set to 3 V. If the sound pressure required for sonic communication is insufficient, the peak-to-peak amplitude Va may be set to a value that is variable within a range from 3 V to 15 V. (Table 1) TIFF0007775691000001.tif33170

[0056] (blood pressure measurement and ultrasonic communication) FIG. 6(A) shows a process flow in which the blood pressure monitor 100 measures the blood pressure at the measurement site while inflating the cuff 20, and transmits the acquired blood pressure value data as biological information as sound waves.

[0057] When the cuff 20 is attached to the measurement site and the user issues a command to start measurement using the measurement switch 52A provided on the main body 10 (step S1 in FIG. 6A), the control unit 110 performs initialization (step S2). Specifically, the control unit 110 initializes the processing memory area, stops the piezoelectric pump 32, and adjusts the pressure sensor 31 to 0 mmHg (setting the atmospheric pressure to 0 mmHg) with the discharge valve 33 open.

[0058] Next, the control unit 110 functions as a pressure control unit, closes the discharge valve 33, and applies the first drive voltage V1 to the piezoelectric pump 32 via the pump drive circuit 320, turning on the fluid supply operation of the piezoelectric pump 32. This starts inflating the cuff 20 (step S3). That is, the control unit 110 supplies air from the piezoelectric pump 32 to the cuff 20 (the fluid bag 22 contained therein) through the air piping 38. At the same time, the pressure sensor 31 functions as a pressure detection unit, detecting the pressure of the fluid bag 22 (cuff pressure Pc) through the air piping 38. The control unit 110 varies the peak-to-peak amplitude Va of the first drive voltage V1 within a range from 15 V to 38 V based on the output of the pressure sensor 31, thereby controlling the inflation speed of the piezoelectric pump 32.

[0059] During this pressurization process, the control unit 110 functions as a blood pressure calculation unit, which is a biological information measurement unit, and attempts to calculate blood pressure values ​​(systolic blood pressure SYS (Systolic Blood Pressure) and diastolic blood pressure DIA (Diastolic Blood Pressure)) using a known oscillometric method based on a signal (pulse wave information) that represents the fluctuation component due to the pulse wave contained in the cuff pressure Pc (step S4). In this example, it also attempts to calculate the pulse rate PLS (beats / min).

[0060] If the control unit 110 is still unable to calculate the blood pressure value and pulse rate due to insufficient data (NO in step S5), it repeats the processes of steps S3 to S5 until the calculations are possible.

[0061] Once the blood pressure value and pulse rate have been calculated in this manner (YES in step S5), the control unit 110 functions as a pressure control unit and removes the first drive voltage V1 from the piezoelectric pump 32 via the pump drive circuit 320 to turn off (stop) the fluid supply operation of the piezoelectric pump 32 (step S6). Subsequently, the control unit 110 opens the exhaust valve 33 and performs control to rapidly exhaust the air in the cuff 20 (fluid bag 22) (step S7).

[0062] Thereafter, the control unit 110 displays the calculated blood pressure value and pulse rate on the display 50 (step S8), and controls the storage of the blood pressure value and pulse rate in the memory 51. Here, the display on the display 50 may be, for example, "SYS:XXX mmHg, DIA:YY mmHg, PLS:ZZ beats / min" (where XXX, YY, and ZZ represent the actual measured values).

[0063] Furthermore, the control unit 110 functions as a sonic communication control unit when the calculation of the blood pressure value and pulse rate is triggered. Specifically, the control unit 110 applies the second drive voltage V2 to the piezoelectric pump 32, causing the piezoelectric pump 32 to generate sonic waves while turning off the fluid supply operation of the piezoelectric pump 32. As a result, the acquired blood pressure value and pulse rate data is transmitted as sonic waves (represented by the symbol SW in FIG. 2) (step S9). The manner of the transmitted sonic waves will be described in detail later. When transmission is complete, the control unit 110 removes the second drive voltage V2 from the piezoelectric pump 32 via the pump drive circuit 320, causing the piezoelectric pump 32 to stop generating sonic waves.

[0064] FIG. 6(B) shows a processing flow in which the smartphone 500 shown in FIG. 2 receives the sound waves SW transmitted from the sphygmomanometer 100, demodulates the data represented by the received sound waves SW, and displays the data.

[0065] In this example, the control unit 510 of the smartphone 500 constantly waits for data received by the sonic wave SW via the microphone 560 (step S11 in FIG. 6B). When data received by the sonic wave SW via the microphone 560 (YES in step S11), the control unit 510 starts pre-installed application software and demodulates the data represented by the sonic wave SW (step S12). Then, the control unit 510 displays the blood pressure value and pulse rate represented by the demodulated data on the display unit 540 (step S13) and performs control to store the blood pressure value and pulse rate in the memory 520. Here, the display on the display unit 540 is similar to that on the display unit 50 of the sphygmomanometer 100, for example, "SYS:XXX mmHg, DIA:YY mmHg, PLS:ZZ beats / min" (where XXX, YY, and ZZ represent actual measured values). In this way, communication can be performed between the sphygmomanometer 100 and the smartphone 500 via the sonic wave SW. The smartphone 500 may transmit the blood pressure value and pulse rate represented by the demodulated data to another device (for example, a server not shown) via the network 900 shown in FIG.

[0066] In this case, in blood pressure monitor 100, piezoelectric pump 32, which is originally provided for controlling the pressure in cuff 20, also serves as a sound generator. This prevents an increase in the number of parts required for transmitting sound waves. As a result, blood pressure monitor 100 can be configured at low cost and in a small size.

[0067] In the above example, calculation of the blood pressure value and pulse rate as biological information is used as a trigger, that is, as the blood pressure value and pulse rate are acquired, sound waves SW representing the blood pressure value and pulse rate are transmitted from the piezoelectric pump 32 (steps S5 to S9 in FIG. 6(A)). In this case, the application of the first drive voltage V1 to the piezoelectric pump 32 and the application of the second drive voltage V2 to the piezoelectric pump 32 are separated in time, and therefore do not interfere with each other.

[0068] The timing of transmitting the sound waves SW representing the blood pressure value and pulse rate is not limited to the above example. For example, the sound waves SW representing the blood pressure value and pulse rate may be transmitted when the fluid supply operation of the piezoelectric pump 32 is turned off except during blood pressure measurement. For example, assume that the communication switch 52C shown in FIG. 2 is pressed while the fluid supply operation of the piezoelectric pump 32 is turned off except during blood pressure measurement, inputting an instruction to transmit blood pressure value data to the outside. The input of this instruction may trigger the control unit 110 to function as a sound wave communication control unit and control the piezoelectric pump 32 to generate sound waves SW representing the blood pressure value and pulse rate stored in the memory 51. As a result, the sound waves SW representing the blood pressure value and pulse rate stored in the memory 51 are transmitted from the piezoelectric pump 32 at a timing desired by the user, other than during measurement. Even in this case, the application of the first drive voltage V1 to the piezoelectric pump 32 and the application of the second drive voltage V2 to the piezoelectric pump 32 are separated in time and therefore do not interfere with each other.

[0069] (transmitted sound waves and demodulated waves) FIG. 8 illustrates waveforms or modes of the sound waves SW, demodulated waves, etc. handled by the sound wave communication system 800 (including the sphygmomanometer 100).

[0070] 8(C), the transmitted / received sound wave SW is an amplitude-shift-keyed wave obtained by amplitude-shift-keying (ASK) a carrier wave having a frequency equal to the frequency f (=17.0 kHz) of the second drive voltage V2 with signals representing the blood pressure value and pulse rate. Specifically, in this example, the sound wave (amplitude-shift-keyed wave) SW alternates over time t between a period showing an H-level (high-level) sound pressure (peak-to-peak amplitude) (referred to as the "H period") and a period showing an L-level (low-level) sound pressure (referred to as the "L period") at a frequency equal to the frequency f of the second drive voltage V2.

[0071] Figure 8(B) shows four periods (denoted by the symbol TD) of the sound wave (amplitude-shift-modulated wave) SW in Figure 8(C), including the H and L periods, with the horizontal axis (time axis) expanded. As can be seen from Figure 8(B), during the H period, the sound pressure (peak-to-peak amplitude) SA is at the H level. During the L period, the sound pressure SA is at the L level, which is lower than the H level. This switching of the sound pressure SA between the H and L levels is achieved by changing the duty of the second drive voltage V2, which changes at a frequency f (=17.0 kHz), as shown in Figure 8(A), for example, from 50% during the H period to 5% during the L period. Here, the duty refers to the ratio of the period during which the second drive voltage V2 is positive to one period (T2 in this example). In this example, the peak-to-peak amplitude Va of the second drive voltage V2 is fixed at 3 V.

[0072] As shown in FIG. 8(C), the sound wave (amplitude shift modulated wave) SW includes a demodulation start signal SOF and a bit string BL representing a binary data "1" or "0" following this demodulation start signal SOF. The demodulation start signal SOF is a signal in which the H level and the L level continue for a predetermined period respectively, indicating that the bit string BL to be demodulated follows immediately after this demodulation start signal SOF. The bit string BL is composed of a plurality of consecutive bits representing a logical value "1" or a logical value "0" for each bit period TB. The data represented by the bit string BL represents, in this example, the blood pressure value and the pulse rate acquired by the sphygmomanometer 100.

[0073] As shown in FIG. 8(D), the logical value (1 or 0) represented by each bit is detected (normalized) according to whether the sound pressure level d at the time when a predetermined period ts (<TB) has elapsed from the start point of the bit period TB within the 1-bit period TB is the H level or the L level. Specifically, the control unit 510 of the smartphone 500 sets a threshold Th between the H level and the L level, and determines the logical value (1 or 0) represented by each bit according to whether the sound pressure level d is higher or lower than this threshold Th. Thereby, as shown in FIG. 8(E), the logical value represented by each bit forming the bit string BL is obtained (that is, a demodulated wave in which the logical value 1 and the logical value 0 are consecutive for each 1-bit period TB). Then, by decoding (deciphering) this demodulated wave by the control unit 510 of the smartphone 500, as shown in FIG. 8(F), in this example, data representing the blood pressure value and the pulse rate is obtained. In this example, according to the blood pressure value and the pulse rate acquired by the sphygmomanometer 100, data of "SYS:XXX mmHg, DIA:YY mmHg, PLS:ZZ beats / min" is obtained (where XXX, YY, and ZZ represent the actually measured numerical values).

[0074] According to the amplitude shift keying (ASK) in the above example, a modulated wave can be generated with a simpler configuration (components) than other digital modulation methods (Frequency Shift Keying (FSK) or Phase Shift Keying (PSK)). Therefore, the blood pressure monitor 100 as a biological information measuring device can be constructed at even lower cost. However, instead of the amplitude shift keying (ASK), the frequency shift keying (FSK) or the phase shift keying (PSK) may be adopted. This can improve the signal-to-noise ratio (SN ratio) and communication quality compared to the case of the amplitude shift keying (ASK).

[0075] (Variation) In the above example (flow in FIG. 6(A)), the blood pressure at the measurement site is measured by the sphygmomanometer 100 while the cuff 20 is being inflated, but this is not limiting. The blood pressure at the measurement site may also be measured by the sphygmomanometer 100 while the cuff 20 is being deflated.

[0076] FIG. 7 shows a process flow in which the sphygmomanometer 100 measures the blood pressure at the measurement site during the decompression process of the cuff 20, and transmits data acquired during blood pressure calculation and calculated blood pressure value data as sound waves.

[0077] When the user instructs the start of measurement using the measurement switch 52A provided on the main body 10 while the cuff 20 is attached to the measurement site (step S101 in FIG. 7), the control unit 110 performs initialization (step S102) in the same manner as in the above example. Specifically, the control unit 110 initializes the processing memory area, stops the piezoelectric pump 32, and adjusts the pressure sensor 31 to 0 mmHg (setting the atmospheric pressure to 0 mmHg) with the discharge valve 33 open.

[0078] Next, the control unit 110 functions as a pressure control unit, closes the discharge valve 33, and applies the above-mentioned first drive voltage V1 to the piezoelectric pump 32 via the pump drive circuit 320, turning on the fluid supply operation of the piezoelectric pump 32. This starts inflating the cuff 20 (step S103). That is, the control unit 110 supplies air from the piezoelectric pump 32 to the cuff 20 (the fluid bag 22 contained therein) through the air piping 38. At the same time, the pressure sensor 31 functions as a pressure detection unit, detecting the pressure of the fluid bag 22 (cuff pressure Pc) through the air piping 38. The control unit 110 varies the peak-to-peak amplitude Va of the first drive voltage V1 within a range from 15 V to 38 V based on the output of the pressure sensor 31, thereby controlling the inflation speed by the piezoelectric pump 32.

[0079] Next, in step S104, the control unit 110 determines whether the cuff pressure Pc has reached a predetermined pressure (referred to as the predetermined pressure Pu). Here, the predetermined pressure Pu is sufficiently higher than the subject's expected systolic blood pressure SYS, and in this example, it is set to Pu = 180 mmHg. If the cuff pressure Pc has not reached the predetermined pressure Pu (NO in step S104), the control unit 110 returns to step S103 and continues pressurizing. Once the cuff pressure Pc reaches the predetermined pressure Pu (YES in step S104 of FIG. 3), the control unit 110 determines that the measurement site has been temporarily occluded, and removes the first drive voltage V1 from the piezoelectric pump 32 via the pump drive circuit 320 to turn off (stop) the fluid supply operation of the piezoelectric pump 32 (step S105). Subsequently, in step S106, the control unit 110 gradually opens the discharge valve 33 via the valve drive circuit 330 to gradually reduce the cuff pressure Pc (decompression process).

[0080] During this pressure reduction process, the control unit 110 functions as a blood pressure calculation unit as a biological information measurement unit, and attempts to calculate blood pressure values ​​(systolic blood pressure SYS (Systolic Blood Pressure) and diastolic blood pressure DIA (Diastolic Blood Pressure)) using a known oscillometric method based on a signal (pulse wave information) representing the fluctuation component due to the pulse wave contained in the cuff pressure Pc (step S107). In this example, it also attempts to calculate the pulse rate PLS (beats / min).

[0081] At the same time, while attempting this calculation, the control unit 110 functions as a sonic communication control unit. Specifically, the control unit 110 applies the second drive voltage V2 to the piezoelectric pump 32 and causes the piezoelectric pump 32 to generate sonic waves while turning off the fluid supply operation of the piezoelectric pump 32. As a result, the acquired data on the cuff pressure Pc and pulse wave information is transmitted as sonic waves SW (step S108). As a result, during the depressurization process, the control unit 110 can transmit the sonic waves SW representing the cuff pressure Pc and pulse wave information in real time while attempting to calculate the blood pressure value and pulse rate. For example, the smartphone 500 may receive the sonic waves SW and display an image representing the cuff pressure Pc and pulse wave information on the display 540. In this case, since the fluid supply operation of the piezoelectric pump 32 is turned off during the depressurization process, the application of the first drive voltage V1 to the piezoelectric pump 32 and the application of the second drive voltage V2 to the piezoelectric pump 32 do not interfere with each other.

[0082] If the control unit 110 is still unable to calculate the blood pressure value and pulse rate due to insufficient data (NO in step S109), it repeats the processes of steps S106 to S109 until the calculations are possible.

[0083] Once the blood pressure value and pulse rate have been calculated in this manner (YES in step S109), the control unit 110 functions as a pressure control unit and controls the opening of the exhaust valve 33 to rapidly exhaust the air in the cuff 20 (fluid bag 22) (step S110).

[0084] Thereafter, the control unit 110 displays the calculated blood pressure value and pulse rate on the display 50 (step S111), and controls the storage of the blood pressure value and pulse rate in the memory 51. Here, as in the above example, the display on the display 50 may be, for example, "SYS:XXX mmHg, DIA:YY mmHg, PLS:ZZ beats / min" (where XXX, YY, and ZZ represent the actual measured values).

[0085] Furthermore, the control unit 110 functions as a sonic communication control unit when the calculation of the blood pressure value and pulse rate is triggered. Specifically, the control unit 110 applies the second drive voltage V2 to the piezoelectric pump 32, causing the piezoelectric pump 32 to generate sonic waves while turning off the fluid supply operation of the piezoelectric pump 32. As a result, the acquired blood pressure value and pulse rate data are transmitted as sonic waves SW (step S112). Upon completion of transmission, the control unit 110 removes the second drive voltage V2 from the piezoelectric pump 32 via the pump drive circuit 320, causing the piezoelectric pump 32 to stop generating sonic waves.

[0086] 7, while the control unit 110 is attempting to calculate blood pressure during the decompression process after the measurement site is temporarily occluded, the sound waves SW representing the cuff pressure Pc and pulse wave information can be transmitted in real time. Furthermore, the calculation of the blood pressure value and pulse rate can be used as a trigger to transmit the acquired blood pressure value and pulse rate data as sound waves SW.

[0087] In the above-described embodiment, the piezoelectric pump 32 is driven by the pump drive circuit 320, and the discharge valve 33 is driven separately by the valve drive circuit 330. However, this is not limited to this. The discharge valve 33 may be a passive valve integrally formed with the piezoelectric pump 32, which automatically closes when the fluid supply operation of the piezoelectric pump 32 is turned on and automatically opens when the fluid supply operation of the piezoelectric pump 32 is turned off. In this case, there is no need to provide the discharge valve 33 separately from the piezoelectric pump 32, and the number of parts is reduced. As a result, the blood pressure monitor 100 can be configured at even lower cost and in a smaller size.

[0088] In the above-described embodiment, the blood pressure monitor 100 as a biological information measuring device measures blood pressure and pulse rate as biological information and transmits the blood pressure and pulse rate data as sound waves SW. However, this is not limited to this. The biological information measuring device of the present invention may measure not only blood pressure and pulse rate as biological information but also electrocardiogram, body temperature, activity level, etc., and transmit the data of such biological information as sound waves SW. For example, the blood pressure monitor 100 may have an electrocardiogram measurement function and transmit sound waves SW representing electrocardiogram information in real time, and the smartphone 500 may receive the sound waves SW and display an image representing the electrocardiogram information on the display 540.

[0089] The above-described embodiments are merely examples, and various modifications are possible without departing from the scope of the present invention. The above-described embodiments can be realized independently, but they can also be combined with each other. Furthermore, the various features of the different embodiments can be realized independently, but they can also be combined with each other. [Explanation of symbols]

[0090] 10,500M main unit 20 Blood pressure cuff 31 Pressure Sensor 32 Piezoelectric pump 33 Discharge valve 100 Sphygmomanometer 500 smartphones 800 Acoustic Communication System

Claims

1. A biological information measurement device for measuring biological information of a measurement site, a piezoelectric pump capable of supplying fluid to compress the measurement site; a pressure control unit that applies a first drive voltage within a predetermined normal range to the piezoelectric pump to turn on a fluid supply operation of the piezoelectric pump, or removes the first drive voltage to turn off a fluid supply operation of the piezoelectric pump, thereby controlling the pressure on the measurement site; a biological information measurement unit that acquires biological information from the measurement site while the pressure on the measurement site is controlled; a sonic wave communication control unit that applies a second drive voltage within a predetermined range to the piezoelectric pump to cause the piezoelectric pump to generate sonic waves, or removes the second drive voltage to stop the piezoelectric pump from generating sonic waves; A biological information measuring device comprising:

2. 2. The biological information measuring device according to claim 1, When the biological information measurement unit acquires biological information from the measurement site, the acquisition of the biological information is used as a trigger for the pressure control unit to remove the first drive voltage and turn off the fluid supply operation of the piezoelectric pump, and the acoustic wave communication control unit applies the second drive voltage to the piezoelectric pump, thereby controlling the piezoelectric pump to generate acoustic waves representing the biological information. A biological information measuring device characterized by:

3. 2. The biological information measuring device according to claim 1, a storage unit that stores the biological information acquired by the biological information measurement unit; an operation unit for inputting instructions from a user; When the fluid supply operation of the piezoelectric pump is turned off, an instruction is input by the operation unit, which triggers the sonic communication control unit to control the piezoelectric pump to generate a sound wave representing the biological information stored in the storage unit. A biological information measuring device characterized by:

4. 4. The biological information measuring device according to claim 1, The sound wave representing the biological information is a modulated wave obtained by amplitude shift modulation of a carrier wave having a predetermined amplitude and frequency with a signal representing the biological information. A biological information measuring device characterized by:

5. 5. The biological information measuring device according to claim 1, a cuff for compressing the measurement site; a pressure sensor for detecting the pressure in the cuff; a drain valve for draining the fluid from the cuff; Equipped with the pressure control unit controls the pressure at the measurement site by supplying fluid to the cuff to pressurize it while applying the first drive voltage to turn on the fluid supply operation of the piezoelectric pump, and / or by discharging the fluid from the cuff via the discharge valve to reduce the pressure while removing the first drive voltage to turn off the fluid supply operation of the piezoelectric pump, During the process of increasing the pressure of the cuff or the process of decreasing the pressure of the cuff by the pressure control unit, the biological information measurement unit calculates a blood pressure value based on pulse wave information representing the pulse wave at the measurement site included in the output of the pressure sensor. A biological information measuring device characterized by:

6. 6. The biological information measuring device according to claim 5, During the pressurization process, the biological information measurement unit calculates a blood pressure value based on the pulse wave information included in the output of the pressure sensor, When the blood pressure value is calculated, the pressure control unit removes the first drive voltage to turn off the fluid supply operation of the piezoelectric pump, and the acoustic communication control unit applies the second drive voltage to the piezoelectric pump to perform control to generate an acoustic wave representing the blood pressure value. A biological information measuring device characterized by:

7. 6. The biological information measuring device according to claim 5, After the pressure of the cuff is increased to temporarily block blood flow to the measurement site, the pressure control unit removes the first drive voltage to turn off the fluid supply operation of the piezoelectric pump, and in this state, during the depressurization process of depressurizing the cuff, the biological information measurement unit attempts to calculate a blood pressure value based on the pulse wave information included in the output of the pressure sensor, and The sonic wave communication control unit applies the second drive voltage to the piezoelectric pump to perform control to generate a sonic wave representing the pulse wave information. A biological information measuring device characterized by:

8. 8. The biological information measuring device according to claim 5, The discharge valve is a passive valve that is integrally formed with the piezoelectric pump, and is configured to close when the fluid supply operation of the piezoelectric pump is turned on, and to open when the fluid supply operation of the piezoelectric pump is turned off. A biological information measuring device characterized by:

9. A sonic wave communication system that uses sonic waves to communicate, The biological information measuring device according to any one of claims 1 to 8, a device having a function of receiving sound waves from the piezoelectric pump; An acoustic wave communication system comprising:

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