Driving circuit for blood pressure measurement and blood pressure measurement device

Abstract

A drive circuit (58') for blood pressure measurement generates: a first drive signal that drives a valve (16) that opens and closes a flow path connected to a blood pressure measurement cuff (70); and a second drive signal that drives a pump that supplies fluid to the cuff (70), wherein the first drive signal and the second drive signal are generated by a common power supply voltage supplied from a power supply circuit (57), and their envelopes have a common shape that changes at the same timing.

Description

Technical Field

[0001] This invention relates to a driving circuit for blood pressure measurement and a blood pressure measuring device. Background Technology

[0002] In recent years, blood pressure measuring devices have been used not only in medical facilities to assess health status but also in homes. These devices, for example, involve inflating and contracting a cuff wrapped around the upper arm or wrist, using a pressure sensor to detect the pressure in the cuff, thereby detecting vibrations in the arterial walls to measure blood pressure.

[0003] Regarding such blood pressure measuring devices, a technique with multiple cuffs is known, wherein the multiple cuffs include a sensing cuff for measuring blood pressure and a pressing cuff for pressing the sensing cuff toward a living body. The blood pressure measuring device has a pump that supplies fluid, such as air, to the cuffs. Furthermore, Japanese Patent Application Publication No. 2013-220288 discloses a configuration, for example, a blood pressure measuring device having an exhaust valve to exhaust air supplied to the cuff. For example, the pump is a piezoelectric pump that includes a piezoelectric element and a diaphragm connected to the piezoelectric element; by applying an alternating voltage, the piezoelectric element vibrates, and the diaphragm vibrates due to the vibration of the piezoelectric element, thereby the piezoelectric pump delivers fluid. For example, the valve is a capacitive type, a normally open exhaust valve whose valve body opens the flow path when no power is applied.

[0004] Such a blood pressure measuring device has a pump drive circuit for driving the pump and a valve drive circuit for driving the valve. When a command to start blood pressure measurement is input, the processor of the blood pressure measuring device outputs a control signal to the valve drive circuit. The valve drive circuit closes the valve based on the control signal. Then, the processor outputs a control signal to the pump drive circuit. The pump drive circuit controls the pump to deliver air to the cuff based on the control signal. The pump drive circuit causes the cuff to inflate with the air supplied by the pump, gradually pressurizing the cuff. The blood pressure measuring device calculates the blood pressure value based on the cuff pressure detected by a pressure sensor. After calculating the blood pressure value, the processor outputs a signal to the pump drive circuit to stop the pump, and the pump drive circuit stops the pump. Furthermore, the processor outputs a control signal to the valve drive circuit to open the valve. The valve drive circuit opens the valve, thereby expelling air from the cuff. In this way, the blood pressure measuring device, using the control signals from the processor, controls the valve and pump using the valve drive circuit and the pump drive circuit to measure the cuff pressure required for blood pressure measurement.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2013-220288 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] Recently, there has been a demand for miniaturization of blood pressure measuring devices as wearable devices worn on the wrist. However, in the existing blood pressure measuring devices described above, the pump and valve have different drive voltages, and therefore the drive circuits for the pump and valve are composed of different circuit blocks. Furthermore, during blood pressure measurement, the processor outputs individual control signals to each drive circuit to control the pump and valve.

[0010] Therefore, when the pump drive circuit and valve drive circuit are composed of different circuit blocks, the circuit area of ​​the drive circuit will increase, and the number of components will also increase. This will become a factor hindering the miniaturization of blood pressure measuring devices.

[0011] Therefore, the object of the present invention is to provide a drive circuit and a blood pressure measuring device that can achieve miniaturization.

[0012] Technical solution

[0013] According to one embodiment, a driving circuit for blood pressure measurement is provided, which generates: a first driving signal that drives a valve to open and close a flow path connected to a blood pressure measuring cuff; and a second driving signal that drives a pump to supply fluid to the cuff, wherein the first driving signal and the second driving signal are generated by a common power supply voltage supplied from a power supply circuit, and the waveform of the first driving signal and the envelope of the peak voltage of the second driving signal have a common shape that changes at the same timing.

[0014] Here, fluids include liquids and air. A cuff includes a bag-like structure that is wrapped around the upper arm, wrist, etc. of an organism when measuring blood pressure and expands by being supplied with fluid; when the fluid is air, the bag-like structure is, for example, an air bag that expands by air.

[0015] According to this scheme, a valve connected to the cuff and a pump supplying fluid to the cuff can be driven by a first drive signal and a second drive signal generated from a common power supply voltage supplied from the power supply circuit. Furthermore, the waveforms of the first drive signal and the envelopes of the second drive signal have a common shape that changes at the same timing. Therefore, it is unnecessary to provide separate drive circuits for the valve and the pump; both the pump and the valve can be driven by a single blood pressure measurement drive circuit. Thus, by using a drive circuit in the blood pressure measurement device, miniaturization and a reduction in the number of components can be achieved.

[0016] A driving circuit for blood pressure measurement is provided, which is the driving circuit for blood pressure measurement of the above-mentioned solution, wherein: a control circuit outputs a second driving signal; and a transformer circuit transforms the power supply voltage into a voltage value corresponding to the first driving signal and the second driving signal and outputs it to the control circuit and the valve.

[0017] According to this scheme, the pump and valve can be driven by the voltage transformed by the transformer circuit. Therefore, the drive circuit integrates the control circuit and the transformer circuit into one unit. That is, the control circuit and the transformer circuit can be set as a single circuit block, thus enabling miniaturization of the drive circuit and a reduction in the number of components. Therefore, by using the drive circuit in a blood pressure measuring device, miniaturization of the blood pressure measuring device can be achieved.

[0018] A driving circuit for blood pressure measurement is provided, which is the blood pressure measurement driving circuit of the above-mentioned solution, wherein the transformer circuit is a boost circuit that boosts the power supply voltage.

[0019] According to this scheme, even if the voltage output from the power supply circuit is lower than the driving signal of the pump and valve, the blood pressure measurement drive circuit can boost the voltage to drive the pump and valve.

[0020] A driving circuit for blood pressure measurement is provided, which is the blood pressure measurement driving circuit of the above-mentioned embodiment, wherein the transformer circuit gradually increases the voltage value output to the valve and the control circuit.

[0021] According to this scheme, by gradually increasing the driving voltage of the cuff, the blood pressure measurement drive circuit can perform the action of pressurizing the cuff by supplying fluid into the cuff at a constant speed, which is considered preferred when performing blood pressure measurement.

[0022] A blood pressure measuring drive circuit is provided, which is the blood pressure measuring drive circuit of the above-mentioned embodiment, wherein the voltage value driving the valve is higher than the voltage at the start of driving the pump, the transformer circuit transforms the power supply voltage to the voltage value driving the valve, and then transforms it to the voltage value maintaining the driving of the valve and driving the pump.

[0023] According to this design, even when the voltage driving the valve is higher than the voltage at the start of pump operation, the blood pressure measurement drive circuit can use the same transformer and control circuit to drive both the valve and the pump. Therefore, miniaturization of the blood pressure measurement drive circuit is possible.

[0024] A blood pressure measuring drive circuit is provided, which is the blood pressure measuring drive circuit of the above-mentioned embodiment, wherein the control circuit outputs a PWM signal with an effective voltage as the first drive signal and the second drive signal to the pump and the valve, wherein the effective voltage is greater than or equal to the voltage required to make the valve and the pump work.

[0025] According to this scheme, the control circuit can use a PWM signal with an effective voltage as the first drive signal and the second drive signal, wherein the effective voltage is greater than or equal to the voltage required to operate the pump supplying fluid to the cuff and the valve connected to the cuff. Therefore, the control circuit can be configured as a single circuit block, thus enabling miniaturization of the drive circuits for driving the pump and valve and reducing the number of components. Therefore, by using a drive circuit for blood pressure measurement in a blood pressure measuring device, miniaturization of the blood pressure measuring device can be achieved.

[0026] A driving circuit for blood pressure measurement is provided, which is a driving circuit for blood pressure measurement according to one of the above-mentioned solutions, wherein the control circuit gradually increases the voltage value of the effective voltage output to the valve and the pump.

[0027] According to this scheme, by gradually increasing the driving voltage of the cuff, the blood pressure measurement drive circuit can perform the action of pressurizing the cuff by supplying fluid into the cuff at a constant speed, which is considered preferred when performing blood pressure measurement.

[0028] A blood pressure measuring drive circuit is provided, which is the blood pressure measuring drive circuit of the above-mentioned embodiment, wherein the voltage value driving the valve is higher than the voltage at the start of driving the pump, and the control circuit sets the effective voltage as the voltage value driving the valve, and then sets it to maintain the voltage value driving the valve and the voltage value driving the pump.

[0029] According to this design, even when the voltage driving the valve is higher than the voltage at the start of pump operation, the blood pressure measurement drive circuit can use the same control circuit to drive both the valve and the pump. Therefore, miniaturization of the blood pressure measurement drive circuit is possible.

[0030] According to one embodiment, a blood pressure measuring device is provided, comprising: a cuff supplied with fluid; a pump supplying the fluid to the cuff; a valve for opening and closing a flow path connected to the cuff; a power supply circuit; a blood pressure measuring drive circuit of the above embodiment; and a processor outputting a voltage control signal to the blood pressure measuring drive circuit.

[0031] According to this scheme, a pump supplying fluid to the cuff and a valve connected to the cuff can be driven by a first drive signal and a second drive signal generated from a common power supply voltage supplied from the power supply circuit. Therefore, there is no need to provide separate drive circuits for the valve and the pump; both the pump and the valve can be driven by a single blood pressure measurement drive circuit. Thus, the blood pressure measurement drive circuit can be configured as a single circuit block, thereby achieving miniaturization of the blood pressure measurement drive circuit and a reduction in the number of components. Therefore, miniaturization of the blood pressure measurement device is possible.

[0032] Invention Effects

[0033] The present invention provides a driving circuit and a blood pressure measuring device that can reduce the circuit area and the number of components. Attached Figure Description

[0034] Figure 1 This is a perspective view showing the configuration of the blood pressure measuring device according to the first embodiment of the present invention.

[0035] Figure 2 This is a block diagram schematically illustrating the structure of the main body of the blood pressure measuring device according to the first embodiment of the present invention.

[0036] Figure 3 This is a block diagram showing the main components of the blood pressure measuring device according to the first embodiment of the present invention.

[0037] Figure 4 This is an explanatory diagram illustrating an example of control during blood pressure measurement using the blood pressure measuring device according to the first embodiment of the present invention.

[0038] Figure 5 This is a flowchart illustrating an example of the use of the blood pressure measuring device according to the first embodiment of the present invention.

[0039] Figure 6 This is a perspective view showing the blood pressure measuring device of the first embodiment of the present invention worn on the wrist.

[0040] Figure 7 This is an explanatory diagram illustrating an example of control during blood pressure measurement using the blood pressure measuring device according to the second embodiment of the present invention.

[0041] Figure 8 This is a block diagram showing the main components of the blood pressure measuring device according to the third embodiment of the present invention. Detailed Implementation

[0042] [First Implementation]

[0043] The following uses Figures 1 to 6 An example of the blood pressure measuring device 1 according to the first embodiment of the present invention will be shown below.

[0044] Figure 1 This is a perspective view showing the configuration of the blood pressure measuring device 1 according to the first embodiment of the present invention. Figure 2 This is a block diagram schematically showing the structure of the main body 2 of the blood pressure measuring device 1. Figure 3 This is a block diagram schematically showing the configuration of the processor 56, power supply circuit 57, drive block 58, pump 14, and valve 16 of the blood pressure measuring device 1. Figure 4 This is an example illustration of the control during blood pressure measurement using blood pressure measuring device 1. Figure 5 This is a flowchart illustrating an example of blood pressure measurement using blood pressure measuring device 1. Figure 6 This is a perspective view showing the blood pressure measuring device 1 being worn on the wrist 200.

[0045] Blood pressure measuring device 1 is an electronic blood pressure measuring device worn on a living organism. For example, blood pressure measuring device 1 is an electronic blood pressure measuring device that is worn on a living organism 200' such as the wrist and measures blood pressure from the arteries of the living organism 200'.

[0046] like Figures 1 to 3 As shown, the blood pressure measuring device 1 includes a device body 2, a fastener 4 such as a strap, a retaining ring 5 disposed between the fastener 4 and the organism 200', and a cuff structure 6 including a cuff 70. It should be noted that in this embodiment, the example of the blood pressure measuring device 1 being worn on the wrist 200, which is the organism 200', is described, but the organism 200' may also be the upper arm or the like.

[0047] like Figure 1 and Figure 2 As shown, the main body 2 of the device includes a housing 11, a display device 12, an operating device 13, a pump 14, a flow path 15, a valve 16, a pressure sensor 17, a power supply unit 18, a communication device 19, and a control board 20.

[0048] The housing 11 may house, for example, a display device 12, an operating device 13, a pump 14, a flow path 15, a valve 16, a pressure sensor 17, a power supply unit 18, a communication device 19, and a control board 20. Furthermore, the housing 11 may expose a portion of the display device 12 in a manner that allows for visual confirmation of the portion of the display device 12 from the outside, or a portion of the housing 11 may be formed of a transparent material.

[0049] The housing 11 may include, for example, a contour housing 31 and a windshield 32, which covers the opening on the side (outer side) of the contour housing 31 opposite to the wrist 200 side. In addition, the housing 11 may also include a base provided inside the contour housing 31, a back cover covering the wrist 200 side of the contour housing 31, and a sealing member that makes the housing 11 impermeable to liquid.

[0050] The profile housing 31 is formed in a cylindrical shape. The profile housing 31 includes, for example, a pair of ears 31a, symmetrically positioned circumferentially on the outer periphery; and spring rods, respectively disposed between the two pairs of ears 31a. The windshield 32 is, for example, a circular glass plate.

[0051] The display device 12 is electrically connected to the control board 20. The display device 12 is, for example, a liquid crystal display (LCD) or an organic electroluminescent display (OELD). The display device 12 displays various information, including date and time, blood pressure values ​​such as highest and lowest blood pressure, and heart rate, according to the control signals from the control board 20.

[0052] The operating device 13 receives commands from the user. For example, the operating device 13 includes multiple buttons 41. Furthermore, the operating device 13 includes sensors that detect operation of the buttons 41, a pressure-sensitive or capacitive touch panel disposed on the housing 11, display device 12, etc., and a microphone that receives voice-based commands. The operating device 13 converts the commands into electrical signals by the user and outputs these electrical signals to the control board 20.

[0053] Pump 14 is, for example, a piezoelectric pump. Pump 14 compresses fluid and supplies the compressed fluid to sleeve 70 via flow path 15. Pump 14 is electrically connected to control board 20 and is driven based on a drive signal (second drive signal) provided from control board 20.

[0054] As a specific example, pump 14 is a pump that includes a piezoelectric element and a diaphragm connected to the piezoelectric element. By applying an AC voltage as a drive signal to the piezoelectric element, the diaphragm vibrates together with the piezoelectric element, and the pump delivers fluid through the vibration of the diaphragm. The drive signal is, for example, a rectangular signal. Furthermore, the fluid can be any gas or any liquid. In this embodiment, the fluid is air. The piezoelectric pump is small and thin, therefore, by using a piezoelectric pump for pump 14, the blood pressure measuring device 1 can be miniaturized.

[0055] The flow path 15 connects the pump 14, valve 16, and pressure sensor 17 to the cuff 70. The flow path 15 can be any one or a combination of a tube, piping, tank, hollow portion formed in the housing 11, and groove. It should be noted that the fluid circuit configuration of the flow path 15 and the cuff 70 is appropriately designed based on various factors such as the fluid flow pattern, the number and configuration of the cuffs 70, the supply sequence of the multiple cuffs 70, the venting method of the multiple cuffs 70, and the blood pressure measurement method.

[0056] Valve 16 is electrically connected to control board 20 and is opened and closed based on a drive voltage (first drive signal) provided from control board 20. Valve 16 opens and closes the flow path to cuff 70. Valve 16 is connected to the atmosphere through flow path section 15, and by switching to the open state, cuff 70 is connected to the atmosphere, thereby expelling air from cuff 70.

[0057] Valve 16 is, for example, a quick-release valve configured to minimize fluid resistance by adjusting the opening degree of valve 16 or the opening area of ​​flow path 15, thereby enabling rapid venting. When air is supplied to cuff 70 during blood pressure measurement, valve 16 is switched to the closed state. Furthermore, when venting air from cuff 70, valve 16 is switched from the closed state to the open state by control of control board 20. Additionally, valve 16 may be configured to allow for adjustment of its opening degree.

[0058] As a specific example, valve 16 is a normally open type that is open under normal conditions and closes by applying a specified voltage. For example, valve 16 may employ an electrostatic actuation type using MEMS (Micro Electro Mechanical System) technology. Among electrostatic actuated valves, there are those with a hysteresis characteristic in the drive voltage. That is, for example, when the drive voltage is increased for a valve in its normally open state to temporarily switch it from the open state to the closed state, even if the drive voltage is subsequently reduced, the valve will remain closed by electrostatic force until a certain limit value is reached.

[0059] Pressure sensor 17 detects the pressure of cuff 70, and in this embodiment, detects the pressure of at least one of the sensing cuffs 73 (described later) among the plurality of cuffs 70 of the cuff structure 6. As a specific example, pressure sensor 17 is fluidly connected to sensing cuff 73 via flow path 15, and detects the pressure within sensing cuff 73. Pressure sensor 17 is electrically connected to control board 20. Pressure sensor 17 outputs an electrical signal corresponding to the detected pressure to control board 20.

[0060] The power supply unit 18 is a power source. The power supply unit 18 is, for example, a secondary battery such as a lithium-ion battery. The power supply unit 18 is electrically connected to the control board 20. Specifically, the power supply unit 18 supplies power to the control board 20. The power supply unit 18 supplies driving power to each component of the control board 20 and, via the control board 20, to the display device 12, the operating device 13, the pump 14, the valve 16, the pressure sensor 17, and the communication device 19.

[0061] The communication device 19 is configured to send and receive information with external devices wirelessly or via wired connection. For example, the communication device 19 sends information controlled by the control board 20, measured blood pressure values, and pulse information to external devices. In addition, it receives software update programs from external devices and sends them to the control unit.

[0062] In this embodiment, the external device is, for example, an external terminal such as a smartphone, tablet, personal computer, or smartwatch.

[0063] In this embodiment, the communication device 19 can be directly connected to an external device or connected via a network. The communication device 19 can also be connected to an external device via mobile communication networks such as 4G and 5G, wireless communication lines such as WiMAX (World Interoperability for Microwave Access), and Wi-Fi. Furthermore, the communication device 19 can also be connected to an external device via wireless communication units such as Bluetooth, NFC (Near Field Communication), and infrared communication. Moreover, the communication device 19 can also be connected to an external device via wired communication lines such as USB (Universal Serial Bus) or cable-based LAN (Local Area Network) connections. Therefore, the communication device 19 can also be configured to include multiple communication units such as a wireless antenna and a micro USB connector.

[0064] like Figure 2 As shown, the control board 20 includes, for example, a board 51, a storage unit 54, and a control unit 55. The control board 20 is configured such that the storage unit 54 and the control unit 55 are mounted on the board 51.

[0065] The control board 51 is housed within the housing 11.

[0066] The storage unit 54 is a memory mounted on the substrate 51. The storage unit 54 includes RAM (Random Access Memory) and ROM (Read Only Memory), etc. The storage unit 54 stores various types of data. For example, the storage unit 54 pre-stores program data used to control the entire blood pressure measuring device 1 and the fluid circuit including the pump 14 and valve 16, setting data used to set various functions of the blood pressure measuring device 1, and calculation data used to calculate blood pressure values ​​and pulse based on the pressure measured by the pressure sensor 17, etc., in a changeable manner. The storage unit 54 stores measured values ​​such as blood pressure and pulse, and information such as the pressure value measured by the pressure sensor 17.

[0067] The control unit 55 includes one or more processors 56, a power supply circuit 57, and a drive block 58 mounted on the substrate 51. The processor 56 is, for example, a CPU (Central Processing Unit). Based on the program stored in the storage unit 54, the power supply circuit 57, the drive block 58, and other circuits, the control unit 55 controls the operation of the entire blood pressure measuring device 1, as well as the operation of the pump 14 and the valve 16, executing predetermined actions (functions). Furthermore, the control unit 55 performs predetermined calculations, analyses, and processing according to the read program. The control unit 55 uses one or more integrated circuits or the like to hardware-configure some or all of the functions executed by the control unit 55.

[0068] like Figure 2 As shown, the control unit 55 is electrically connected to the display device 12, the operating device 13, the pump 14, the valve 16, and the pressure sensor 17, and supplies them with power. Furthermore, the control unit 55 controls the operation of the display device 12, the pump 14, and the valve 16 based on the electrical signals output from the operating device 13 and the pressure sensor 17. The control unit 55 controls the pump 14 and the valve 16 to supply air to the cuff 70, and calculates the blood pressure using an oscillometric method based on the pressure of the sensing cuff 73 detected by the pressure sensor 17.

[0069] For example, the processor 56 includes a main CPU that controls the operation of the entire blood pressure measuring device 1 and a secondary CPU that controls the operation of the fluid circuit. It should be noted that, for example, the control unit 55 may also be configured to perform all control of the blood pressure measuring device 1 via a single CPU. Furthermore, for example, the processor 56 calculates measurement results such as maximum and minimum blood pressure values, heart rate, etc., based on the electrical signal output from the pressure sensor 17, and outputs an image signal corresponding to the measurement results to the display device 12.

[0070] Furthermore, for example, when a command to measure blood pressure is input from the operating device 13, the processor 56 outputs command values ​​such as frequency signals and voltage signals to the drive block 58 for driving the pump 14 and valve 16. The processor 56 also controls the driving and stopping of the pump 14 and the opening and closing of the valve 16 based on the electrical signal output by the pressure sensor 17. The processor 56 supplies compressed air to the cuff 70 by controlling the pump 14 and valve 16, and selectively depressurizes the cuff 70.

[0071] It should be noted that, in this embodiment, the frequency signal is a signal that specifies the frequency of the rectangular wave driving the pump 14. Furthermore, in this embodiment, the voltage signal is a signal that specifies the voltage value used to drive the pump 14 and the valve 16. The voltage signal is a common signal for both the pump 14 and the valve 16, and it contains information about the voltage values ​​output to the pump 14 and the valve 16.

[0072] Furthermore, in this embodiment, for valve 16, the drive voltage for switching from the open state to the closed state is set to be higher than the voltage of the drive signal output to pump 14 at the start of blood pressure measurement, and the drive voltage for switching from the closed state to the open state is set to 0V or lower than the voltage of the drive signal output to pump 14 at the start of blood pressure measurement.

[0073] The power supply circuit 57 supplies power from the power supply unit 18 to the drive block 58. It should be noted that the power supply circuit 57 may also be configured to supply power for driving the display device 12, the operation device 13, the pressure sensor 17, the communication device 19, and the processor 56. Furthermore, for example, it may be configured such that the control unit 55, in addition to the power supply circuit 57 which supplies power from the power supply unit 18 to the drive block 58, also has a power supply circuit that supplies power from the power supply unit 18 to the display device 12, the operation device 13, the pressure sensor 17, the communication device 19, and the processor 56.

[0074] The drive block 58 includes a transformer circuit 59 and a control circuit 60. The drive block 58 integrates the transformer circuit 59 and the control circuit 60 into a single circuit block. The drive block 58 is a drive circuit that drives the pump 14 and the valve 16 via the transformer circuit 59 and the control circuit 60. The drive block 58 is a drive circuit for blood pressure measurement.

[0075] The transformer circuit 59 transforms the power supply voltage supplied from the power supply circuit 57. For example, the transformer circuit 59 is a boost circuit that increases the power supply voltage supplied from the power supply circuit 57. In this embodiment, the transformer circuit 59 will be described as a boost circuit 59'.

[0076] like Figure 3 As shown, the boost circuit 59' is connected to the power supply circuit 57, the control circuit 60, and the valve 16. The input of the boost circuit 59' is connected to the power supply circuit 57 and the control circuit 60. The output of the boost circuit 59' is connected to the control circuit 60 and the valve 16.

[0077] The boost circuit 59' boosts the voltage input from the power supply circuit 57 based on the voltage signal output from the processor 56 and outputs it to the valve 16 and the control circuit 60. It should be noted that the voltage signal output from the processor 56 is input to the boost circuit 59' directly from the processor 56 or indirectly via the control circuit 60. In this embodiment, an example is used where the voltage signal output from the processor 56 is input to the boost circuit 59' via the control circuit 60 for illustration.

[0078] Control circuit 60 is connected to processor 56, boost circuit 59', and pump 14. The input of control circuit 60 is connected to processor 56 and boost circuit 59'. The output of control circuit 60 is connected to boost circuit 59' and pump 14. When a frequency signal and a voltage signal output from processor 56 are input, control circuit 60 outputs a voltage signal to boost circuit 59'. Furthermore, control circuit 60 sets the voltage boosted by boost circuit 59' into a rectangular signal based on the frequency signal and outputs it to pump 14.

[0079] like Figure 1 and Figure 6 As shown, the fastener 4 is a so-called strap, having a first strap 61 with a pair of ears 31a and a spring rod on one side, and a second strap 62 with a pair of ears 31a and a spring rod on the other side. When the blood pressure measuring device 1 is worn on the wrist 200, the fastener 4 is wrapped around the wrist 200 through the retaining ring 5.

[0080] The first belt 61, referred to as the so-called mother belt, is configured as a belt that can be connected to the second belt 62. The first belt 61 has a belt portion 61a and a buckle 61b. The belt portion 61a is configured as a belt. The belt portion 61a is formed of a resin material that can be elastically deformed. In addition, the belt portion 61a is flexible and has a sheet-like insert member inside that inhibits the stretching and contraction of the belt portion 61a in the longitudinal direction.

[0081] The buckle 61b has a rectangular frame-shaped body 61e and a latch 61f rotatably mounted on the frame-shaped body 61e. One side of the frame-shaped body 61e with the latch 61f is rotatably mounted on the strap portion 61a. The first strap 61 is mounted between a pair of ears 31a via a spring rod and is rotatably held in the contour housing 31.

[0082] The second strip 62, referred to as a hook strip, is configured as a strip with a width that can be inserted into the frame 61e. The second strip 62 is formed of a resin material that can be elastically deformed. Furthermore, the second strip 62 is flexible and has a sheet-like insert member inside that inhibits the stretching and contraction of the second strip 62 in the longitudinal direction.

[0083] Furthermore, the second band 62 has a plurality of small holes 62a for inserting the latch 61f. The second band 62 is fitted between a pair of ears 31a via a spring rod and is rotatably held in the contour housing 31.

[0084] When the first band 61 and the second band 62 are connected, the fastener 4 and the device body 2 together form a ring shape that mimics the circumference of the wrist 200. The fastener 4 presses the retaining ring 5 toward the wrist 200, causing the retaining ring 5 to elastically deform in a manner that mimics the circumference of the wrist 200 of the wearer of the blood pressure measuring device 1.

[0085] The retaining ring 5 is configured as a circumferentially curved band mimicking the shape of the wrist 200. The retaining ring 5 is formed with one end separate from the other. For example, the outer surface of one end of the retaining ring 5 is fixed to the device body 2. One end and the other end of the retaining ring 5 are positioned to protrude laterally toward the wrist 200. Thus, when the blood pressure measuring device 1 is worn on the wrist 200, one end and the other end of the retaining ring 5 are positioned laterally toward the wrist 200. Furthermore, one end and the other end of the retaining ring 5 are adjacent to each other at a predetermined distance. The retaining ring 5 is, for example, made of resin material.

[0086] As a specific example, the retaining ring 5 is configured as a band that curves circumferentially in imitation of the wrist. Furthermore, as a specific example, in the retaining ring 5, the shorter side extending from the device body 2 to one end is positioned on the back of the wrist, and the longer side extending from the back of the wrist to the other end extends from the back of the wrist, across one side, to the palm side of the wrist 200.

[0087] The cuff structure 6 includes multiple cuffs. When measuring blood pressure, the cuff structure 6 is wrapped around the wrist of an organism. The cuff 70 is a blood pressure measuring cuff. The cuff 70 includes one or more bag-like structures to which fluid is supplied. The bag-like structure is the component to which fluid is supplied. In this embodiment, the fluid is air, therefore the bag-like structure is an air bag. The bag-like structure is formed, for example, by overlapping and welding a pair of sheet components.

[0088] For example, the cuff structure 6 includes a pressing cuff 71 as a cuff 70, a back plate 72, and a sensing cuff 73 as a cuff 70. The cuff structure 6 may also have a stretching cuff as another cuff 70. The pressing cuff 71 is fluidly connected to the pump 14. The pressing cuff 71 expands with air from the pump 14. The pressing cuff 71 presses the sensing cuff 73 against the organism by expanding. The pressing cuff 71 is formed, for example, by stacking multiple fluidly connected air bags in the pressing direction of the sensing cuff 73.

[0089] The backplate 72 is formed into a plate shape from resin material. The backplate 72 has shape adaptability.

[0090] Here, shape following refers to the function of the back plate 72 to deform in a manner that mimics the shape of the contacted portion of the wrist 200, which is the area of ​​the wrist 200 opposite to the back plate 72. This contact includes both direct contact between the back plate 72 and the wrist 200, and indirect contact via the sensing cuff 73. The back plate 72 is formed to cover the palm side of the wrist 200. The back plate 72, while conforming to the shape of the wrist 200, presses the sensing cuff 73 by inflating the cuff 71.

[0091] The sensing cuff 73 is supplied with air by the pump 14. When the blood pressure measuring device 1 is worn on a living body, the sensing cuff 73 is positioned in the area of ​​the wrist (living body) 200 where an artery is present. During blood pressure measurement, the sensing cuff 73, used to detect the pressure used to calculate blood pressure, is supplied with air and pressed by the inflated compression cuff 71, thereby compressing the area of ​​the wrist 200 where an artery is present. The sensing cuff 73 is formed, for example, by an air bag.

[0092] Next, the following uses Figure 4 An example will be given illustrating the relationship between voltage, rectangular signal, valve opening and closing, and cuff pressure from the start of blood pressure measurement using such a blood pressure measuring device 1 (t1) to the end of blood pressure measurement (t3). It should be noted that this example of blood pressure measurement does not include correction of the rectangular signal based on the cuff pressure.

[0093] Figure 4 In this circuit, voltage one is the voltage output from power supply circuit 57 to boost circuit 59'. Voltage two is the voltage output from boost circuit 59' to control circuit 60 and valve 16. The rectangular signal is the signal used to drive pump 14, output from control circuit 60 to pump 14.

[0094] First, when a command to start blood pressure measurement is input via the operating device 13, the processor 56 outputs a frequency signal and a voltage signal, which serve as the drive signal for the pump 14, to the control circuit 60. Then, the control circuit 60 outputs the input voltage signal to the boost circuit 59'. At this time, the processor 56 outputs a voltage signal representing the closing voltage of the valve 16 to the control circuit 60 as the signal for the start of blood pressure measurement.

[0095] The boost circuit 59' boosts the voltage input from the power supply circuit 57 to a voltage that drives the valve 16 to close, based on the voltage signal indicated by the control circuit 60, and outputs the boosted voltage to the control circuit 60 and the valve 16. The control circuit 60 generates a rectangular signal based on the voltage and frequency signal and outputs it to the pump 14. Here, the electrical signal output from the processor 56 is maintained at the valve 16 closing voltage value for the period from the start of blood pressure measurement t1 until the predetermined time t2 has elapsed when the valve 16 is reliably closed. Thus, the valve 16 closes due to the voltage of the rectangular signal from t1 to t2. Furthermore, the diaphragm of the pump 14 vibrates according to the voltage value and frequency of the rectangular signal, thereby increasing the pressure within the cuff 70.

[0096] Here, the drive voltage V0 used to switch valve 16 from the open state to the closed state is set to be higher than the drive voltage used to switch valve 16 from the closed state to the open state. Furthermore, the drive voltage used to switch valve 16 from the closed state to the open state is set to be lower than the amplitude value of the drive voltage of pump 14. Therefore, valve 16 can be switched from the open state to the closed state by increasing voltage two to V0 at the start of blood pressure measurement, and then the drive of pump 14 can be controlled while valve 16 is kept closed by decreasing voltage two to the voltage required to drive pump 14. It should be noted that the time t2-t1 required to switch valve 16 from the open state to the closed state is a few ms to tens of ms, which is very short compared to the drive time t3-t1 of pump 14. Therefore, the effect of pump 14 drive caused by drive voltage V0 on the pressure control within the cuff is negligible.

[0097] From the start of blood pressure measurement (t1) until the elapsed time (t2), processor 56 outputs a voltage signal to control circuit 60 corresponding to the voltage value driving pump 14 without opening valve 16. At this time, processor 56 outputs the voltage signal in a manner that gradually increases the voltage value driving pump 14. Therefore, from the elapsed time (t2) until the end of blood pressure measurement (t3), valve 16 remains closed, and the voltage of voltage two output from boost circuit 59' gradually increases. Control circuit 60 generates a rectangular signal based on the input voltage two. Therefore, the amplitude of the rectangular signal input to pump 14 gradually increases. Consequently, the amount of air supplied by pump 14 to cuff 70 gradually increases, and the pressure within cuff 70 gradually increases.

[0098] Furthermore, when the blood pressure measurement ends, the processor 56 outputs a stop signal to the control circuit 60. For example, the stop signal may be a frequency signal (0Hz) and a voltage signal (0V). When the stop signal is input, the control circuit 60 stops generating the rectangular signal and outputs a stop signal to the boost circuit 59'. When the stop signal is input, the boost circuit 59' stops boosting the voltage supplied from the power supply circuit 57 and stops the output of the voltage check valve 16 and the control circuit 60. Therefore, the voltage input to valve 16 becomes 0V, and after the blood pressure measurement ends (t3), valve 16 is no longer energized. Thus, the closed valve 16 opens, thereby expelling air from the cuff 70, and the pressure inside the cuff 70 becomes atmospheric pressure.

[0099] Next, use Figure 5 The flowchart shown illustrates an example of blood pressure measurement using such a blood pressure measuring device 1.

[0100] First, when measuring blood pressure, the user, such as Figure 6The blood pressure measuring device 1 is worn on the wrist 200 as shown, and the power supply to the blood pressure measuring device 1 is turned on. Then, when the user operates the operating device 13 and inputs the command to start the blood pressure measurement, the processor 56 outputs a frequency signal and a voltage signal (step ST11).

[0101] The boost circuit 59' boosts the power supply voltage input from the power supply circuit 57 based on the voltage signal output by the processor 56 and input via the control circuit 60. Then, the boost circuit 59' outputs the generated boost voltage to the valve 16, driving the valve 16 to close (step ST21).

[0102] The control circuit 60 generates a rectangular signal based on the frequency signal output from the processor 56 and the boosted voltage generated by the boost circuit 59'. Then, the control circuit 60 outputs the generated rectangular signal to the pump 14, driving the pump 14 based on the rectangular signal (step ST31). It should be noted that, in order to supply air to the cuff 70 at a constant speed, the voltage signal output by the processor 56 is controlled by gradually increasing the voltage boosted by the boost circuit 59'.

[0103] After valve 16 is closed and pump 14 is activated, processor 56 determines whether cuff 70 is being pressurized at a target speed (step ST12). For example, processor 56 calculates the change in pressure within cuff 70 relative to time detected by pressure sensor 17 connected to cuff 70, compares the change in pressure within cuff 70 with the pressurization speed of cuff 70 pre-stored in storage unit 54, and thereby determines whether cuff 70 is being pressurized at the target speed. If cuff 70 is not being pressurized at the target speed, for example, if the pressurization speed is faster or slower than the target speed (No in step ST12), a corrected frequency signal and voltage signal are output to control circuit 60 (step ST13).

[0104] It should be noted that, regarding the corrected frequency signal and voltage signal, the processor 56 may output the corrected frequency signal and voltage signal based on and read the data table stored in the storage unit 54. Alternatively, the processor 56 may calculate the corrected frequency signal and voltage signal according to a program, or the corrected frequency signal and voltage signal may be generated by other methods.

[0105] The control circuit 60 outputs the corrected voltage signal to the boost circuit 59'. When a boost voltage based on the corrected voltage signal is input to the boost circuit 59', the control circuit 60 generates a rectangular signal based on the frequency signal and the boost voltage, and drives the pump 14 through the corrected rectangular signal (step ST32).

[0106] If the cuff 70 is being inflated at the target rate (yes in step ST12), the processor 56 determines whether the blood pressure measurement has ended (step ST14). If the blood pressure measurement has not ended (no in step ST14), the processor 56 returns to step ST12 and determines whether the cuff 70 is being inflated at the target rate.

[0107] When the blood pressure measurement has ended (step ST14), the processor 56 outputs a stop signal to the control circuit 60 (step ST15). When a stop signal is input to the control circuit 60, the control circuit 60 outputs a stop signal to the boost circuit 59'. When the boost circuit 59' receives a stop signal, the boost voltage generated based on the voltage signal disappears, i.e., no boost voltage is generated, therefore no boost voltage is input to the valve 16, and the valve 16 is opened (step ST22). Furthermore, the control circuit 60 does not input boost voltage from the boost circuit 59', and the generation of the rectangular signal stops. As a result, the pump 14 stops (step ST33), and the blood pressure measurement ends.

[0108] According to the blood pressure measuring device 1 configured as described above, including the drive block (drive circuit) 58, the boosted voltage output from a boost circuit 59' can be used to drive the valve 16 and generate rectangular signals for driving the pump 14. That is, the drive voltage of the valve 16 (first drive signal) and the drive signal of the pump 14 (rectangular signal, second drive signal) are the same voltage value. That is, the waveform of the drive voltage of the valve 16 (first drive signal) and the envelope of the drive signal of the pump 14 (rectangular signal, second drive signal) have a common shape that changes at the same timing.

[0109] Specifically, such as Figure 4 As shown, the waveform of the drive signal (first drive signal) for the drive valve 16 and Figure 4 The envelope of the peak voltage of the rectangular signal (second drive signal) that serves as the drive signal for the drive pump 14, shown by the single-dotted dashed line, is the slope that changes at the same timing.

[0110] Therefore, the boost circuit 59' and the control circuit 60 can be integrated into a single circuit block. This allows for miniaturization of the drive circuit, i.e., the drive block 58, that drives the pump 14 and the valve 16. Furthermore, the number of components used to construct the drive block 58 that drives the pump 14 and the valve 16 can be reduced. Therefore, the drive block 58 can be miniaturized, thus enabling miniaturization of the blood pressure measuring device 1.

[0111] Furthermore, when using the blood pressure measuring device 1 to measure blood pressure, it is preferable to pressurize the cuff 70 by supplying air into it at a constant rate. Therefore, the driving voltage of the pump 14 is gradually increased. The minimum driving voltage of the pump 14 is set to the driving voltage required to switch the valve 16 from the open state to the closed state, or higher than the voltage required to maintain the closed state after the valve 16 is driven into the closed state. In this embodiment, after boosting the input voltage to the voltage required to drive the valve 16 from the open state to the closed state via the boost circuit 59', thereby driving the valve 16, the boosted voltage is reduced to a voltage higher than the lower limit voltage required to maintain the closed state of the valve 16 to generate a rectangular signal, thereby driving the pump 14. Furthermore, by gradually increasing the boosted voltage to drive the pump 14, the pump 14 can be driven, thus enabling both the driving of the pump 14 and the maintenance of the closed state of the valve 16. Thus, the drive block 58 can generate a boost voltage for driving the pump 14 and valve 16 through a boost circuit 59'.

[0112] Furthermore, the blood pressure measuring device 1 uses a normally open valve 16 for venting air from the cuff 70. Therefore, in case of an abnormality, the blood pressure measuring device 1 can stop the supply of air from the pump 14 to the cuff 70 by stopping the drive block 58, and can also open the valve 16 to quickly vent air from the cuff 70.

[0113] As described above, the drive block (drive circuit) 58 and blood pressure measuring device 1 according to this embodiment can reduce the circuit area, reduce the number of components, and drive the pump 14 and valve 16 through a single drive block (drive circuit) 58.

[0114] [Other Implementation Methods]

[0115] It should be noted that the present invention is not limited to the embodiments described above. For example, in the above examples, the following example was described, but it is not limited thereto: with regard to valve 16, the drive voltage for switching from the open state to the closed state is set to be higher than the voltage of the drive signal output to pump 14 at the start of blood pressure measurement, and the drive voltage for switching from the closed state to the open state is 0V or lower than the voltage of the drive signal output to pump 14 during blood pressure measurement.

[0116] For example, such as Figure 7 As shown in the example of the control of the blood pressure measuring device 1 of the second embodiment, with regard to valve 16, the driving voltage for switching from the open state to the closed state can also be set to be the same as or lower than the voltage of the driving pump 14 at the start of blood pressure measurement t1. When using such a valve 16, as... Figure 7As shown, at the start of blood pressure measurement t1, the boost circuit 59' boosts the voltage to drive the pump 14 and outputs this boosted voltage to the control circuit 60 and valve 16, thereby driving the pump 14 and closing the valve 16. Furthermore, the valve 16 remains closed while the pump 14 is driven.

[0117] It should be noted that valve 16 can also be a normally closed type. That is, as long as the configuration allows the pump 14 and valve 16 to be driven at the same voltage value via drive block 58, the type and usage of valve 16 can be appropriately set. For example, in the case of normally closed valve 16, valve 16 is positioned in the flow path between pump 14 and sleeve 70.

[0118] Furthermore, for example, in the above example, an example of driving pump 14 and valve 16 via drive block 58 was described, but there can also be multiple pumps 14 and valves 16. That is, even if the blood pressure measuring device 1 is configured to have one or both of multiple pumps 14 and valves 16, multiple pumps 14 and / or multiple valves 16 can be driven by one drive block 58 as long as control is used to drive them with the same voltage value. Furthermore, the cuff 70 connected to the pump 14 and valve 16 can be one or multiple. In the case where multiple cuffs 70 are connected to the pump 14 and valve 16, for example, they can be as follows: Figure 8 As shown in the example, multiple cuffs 70 are connected in series. In addition, although not shown, multiple cuffs 70 can also be connected in parallel.

[0119] Furthermore, in the above example, the transformer circuit 59 of the drive block (drive circuit) 58 was described as a boost circuit, but it is not limited to this. For example, the transformer circuit 59 can also be a buck circuit, or even a buck-boost circuit. That is, as long as the voltage output from the power supply circuit 57 can be transformed into the voltage value that drives the pump 14 and the valve 16, the transformer circuit 59 can be appropriately configured.

[0120] Furthermore, in the above example, the configuration of the drive block 58 having a transformer circuit 59 has been described, but it is not limited to this. For example, when the drive voltage of valve 16 and pump 14 is lower than the output voltage of power supply circuit 57, it is also possible to... Figure 8 As shown, the drive block 58 does not have a transformer circuit. In this case, for example, the control circuit 60 generates a PWM (Pulse Width Modulation) signal with an effective voltage corresponding to the voltage signal output from the processor 56. That is, the effective voltage corresponding to the voltage signal is set by controlling the duty cycle (= pulse width / period) of the rectangular signal.

[0121] Furthermore, the control circuit 60 outputs the PWM signal as a drive signal to valve 16 and pump 14. The effective voltage is generated to be greater than or equal to the voltage required to operate valve 16, and is also generated to be suitable for controlling the amount of air discharged from pump 14. For example, it can also be as follows: Figure 4 and Figure 7 As shown in the diagram, the voltage value (RMS) of the effective voltage is gradually increased, similar to a rectangular signal. Alternatively, it can be configured such that the voltage is controlled to the RMS value corresponding to the drive voltage of valve 16, and then controlled to the RMS value corresponding to the drive voltage of pump 14. It should be noted that, for example, a rotary type can be used for pump 14, and a solenoid type for valve 16. Thus, the drive block 58, including the control circuit 60, can drive pump 14 and valve 16 via a PWM signal. Furthermore, by employing the control circuit 60 that controls the duty cycle, the drive block 58 does not require a transformer circuit 59, thereby achieving miniaturization and a reduction in the number of components.

[0122] That is, the present invention is not limited to the above-described embodiments, and various modifications can be made during the implementation phase without departing from its spirit. Furthermore, the embodiments can be appropriately combined as much as possible, in which case the combined effect can be obtained. Moreover, the inventions included in the above embodiments at various stages can be derived through appropriate combinations of the disclosed constituent elements.

[0123] Explanation of reference numerals in the attached figures

[0124] 1: Blood pressure measuring device; 2: Main body of the device; 4: Fasteners; 5: Card ring; 6: Cuff construction; 11: Shell; 12: Display device; 13: Operating device; 14: Pump; 15: Flow path part; 16: Valve; 17: Pressure sensor; 18: Power Supply Department; 19: Communication device; 20: Control board; 31: Outline shell; 31a: Ear; 32: Windshield; 41: Button; 51: substrate; 54: Storage Department; 55: Control Department; 56: Processor; 57: Power supply circuit; 58: Driver block (drive circuit); 59: Transformer circuit (boost circuit); 60: Control circuit; 61: First zone; 61a: Belt section; 61b: Buckle; 61e: frame body; 61f: Button tongue; 62: Second band; 62a: small hole; 70: Cuffs; 71: Press the cuff; 72: Back panel; 73: Sensing cuff; 200: Wrist (organism).

Claims

1. A driving circuit for blood pressure measurement, generating: a first driving signal to drive a valve that opens and closes a flow path connected to a blood pressure measuring cuff; and a second driving signal to drive a pump that supplies fluid to the cuff, wherein, The first drive signal and the second drive signal are generated by a common power supply voltage supplied from the power supply circuit, and the waveforms of the first drive signal and the envelopes of the peak voltages of the second drive signal have slopes that change simultaneously.

2. The driving circuit for blood pressure measurement according to claim 1, wherein, include: The control circuit outputs the second drive signal; as well as The transformer circuit transforms the power supply voltage into a voltage value corresponding to the first drive signal and the second drive signal, and outputs it to the control circuit and the valve.

3. The driving circuit for blood pressure measurement according to claim 2, wherein, The transformer circuit is a boost circuit that increases the power supply voltage.

4. The driving circuit for blood pressure measurement according to claim 2 or 3, wherein, The transformer circuit gradually increases the voltage value output to the valve and the control circuit.

5. The driving circuit for blood pressure measurement according to claim 2 or 3, wherein, The voltage driving the valve is higher than the voltage at which the pump starts operating. The transformer circuit transforms the power supply voltage into a voltage value that drives the valve, and then transforms it into a voltage value that maintains the valve's operation and drives the pump.

6. The driving circuit for blood pressure measurement according to claim 2, wherein, The control circuit outputs a PWM signal with an effective voltage as the first drive signal and the second drive signal to the pump and the valve, wherein the effective voltage is greater than or equal to the voltage required to make the valve and the pump work.

7. The driving circuit for blood pressure measurement according to claim 6, wherein, The control circuit gradually increases the voltage value of the effective voltage output to the valve and the pump.

8. The driving circuit for blood pressure measurement according to claim 6 or 7, wherein, The voltage driving the valve is higher than the voltage at which the pump starts operating. The control circuit sets the effective voltage to the voltage value that drives the valve, and then sets it to the voltage value that maintains the valve's drive and drives the pump.

9. A blood pressure measuring device, comprising: The cuff is supplied with fluid; The pump supplies the fluid to the cuff; A valve that opens and closes the flow path connected to the cuff; Power supply circuit; Blood pressure measuring drive circuit as described in any one of claims 1 to 8; as well as The processor outputs the voltage control signal to the drive circuit for blood pressure measurement.

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