Fluid circuit and blood pressure measuring device

Abstract

The fluid circuit (3) of the blood pressure measuring device (1) includes: a first cuff (71) connected to the secondary side of a pump (14) that supplies fluid to the secondary side; a second cuff (73) connected to the secondary side of the first cuff (71); a first valve (21) provided between the first cuff (71) and the second cuff (73), which closes when the pressure difference between the first cuff (71) and the second cuff (73) becomes a specified pressure difference; and a flow restrictor (22) provided between the first valve (21) and the second cuff (73).

Description

Technical Field

[0001] The present invention relates to a fluid circuit for blood pressure measurement and a blood pressure measurement device. Background Art

[0002] In recent years, blood pressure measurement devices for measuring blood pressure are used not only in medical facilities but also at home as a means of confirming the health status. For example, a blood pressure measurement device expands and contracts a cuff wrapped around the upper arm or wrist of a living body, and detects the pressure of the cuff by a pressure sensor, thereby detecting the vibration of the arterial wall to measure blood pressure.

[0003] Regarding such a blood pressure measurement device, a technique including a plurality of cuffs is known, and the plurality of cuffs include a sensing cuff for measuring blood pressure and a pressing cuff for pressing the sensing cuff against the living body. The blood pressure measurement device has a pump, and supplies a fluid such as air to the cuff through the pump, thereby expanding the cuff.

[0004] For example, in Japanese Patent Laid-Open No. 2009-22477, as such a blood pressure measurement device, a technique including a fluid circuit is disclosed in which a throttle member is disposed between the pressing cuff and the sensing cuff as a fluid resistance to reduce the air injection amount. In such a blood pressure measurement device, the flow rate changes in proportion to the pressure difference between the pressing cuff on the primary side of the throttle member and the sensing cuff on the secondary side.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Patent Laid-Open No. 2009-22477 Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] In the above blood pressure measurement device, the flow rate of the air supplied from the pump changes in proportion to the pressure difference between the pressing cuff on the primary side of the throttle member and the sensing cuff on the secondary side of the throttle member. Therefore, when the pressurization time of the living body during blood pressure measurement changes, the air inflow amount into the sensing cuff changes, and an error occurs in the air injection amount into the sensing cuff.

[0010] In addition, even in a configuration including three or more cuffs, when a fluid resistance such as a throttle member is provided between the primary side cuff and the secondary side cuff, the air inflow amount into the secondary side cuff changes.

[0011] In addition, the pressurization time of the living body during blood pressure measurement varies depending on the thickness of the measurement site of the subject, the winding state of the armband, the pump characteristics, etc. In addition, it is necessary to make the amount of air injected into the sensing cuff less than the amount of inhalation injected into the pressing cuff. Therefore, for the throttle member provided between the pressing cuff and the sensing cuff, a throttle member with a large fluid resistance needs to be used. Such a throttle member requires a tiny pinhole and high-cost and high-precision processing technology.

[0012] Therefore, an object of the present invention is to provide a fluid circuit and a blood pressure measurement device capable of controlling the amount of air injected into the cuff to be constant.

[0013] Technical solution

[0014] According to one aspect, there is provided a fluid circuit including: a first cuff connected to the secondary side of a pump that supplies fluid to the secondary side; a second cuff connected to the secondary side of the first cuff; a first valve provided between the first cuff and the second cuff and closing when the pressure difference between the first cuff and the second cuff becomes a specified pressure difference; and a flow restrictor provided between the first valve and the second cuff and on the secondary side of the first valve.

[0015] Here, the fluid includes liquid and air. The cuff includes a bag-shaped structure that is wound around the upper arm, wrist, etc. of the living body during blood pressure measurement and expands by being supplied with fluid. When the fluid is air, the bag-shaped structure is, for example, an air bag that expands by air.

[0016] According to this aspect, the fluid supplied to the secondary side by the pump is supplied to the first cuff and passes through the flow restrictor to be supplied to the second cuff. Therefore, the flow rate of the air supplied to the second cuff is less than the flow rate of the air supplied to the first cuff. Therefore, the pressure of the first cuff is higher than the pressure of the second cuff. In addition, when the pressure difference between the first cuff and the second cuff becomes a specified pressure difference, the first valve closes, so the supply of fluid to the second cuff stops. Therefore, the fluid circuit can make the amount of fluid injected into the second cuff constant. In addition, the fluid circuit is set to close the first valve at the pressure difference between the first cuff and the second cuff when the second cuff reaches the desired pressure, so that the amount of fluid supplied to the second cuff when the pressure of the second cuff becomes the desired pressure can be supplied.

[0017] The fluid circuit of the above aspect is provided with: a second valve provided in parallel with the first valve and the flow restrictor and opening when the pressure of the first cuff is lower than the pressure of the second cuff.

[0018] According to this solution, in the fluid circuit, when the pressure of the first cuff drops due to discharging the fluid of the first cuff and the second cuff, etc., and the pressure of the first cuff is lower than the pressure of the second cuff, the second valve opens. Therefore, when the pressure of the first cuff is higher than the pressure of the second cuff, the fluid of the first cuff is preferentially discharged, and the fluid of the second cuff is discharged through the flow restrictor. In addition, when the pressure of the first cuff is lower than the pressure of the second cuff, the second valve opens, and the discharge speed of the fluid of the second cuff increases.

[0019] According to one solution, a blood pressure measurement device is provided, which includes: a pump that supplies fluid to the secondary side; the fluid circuit of the above solution; an on-off valve provided between the pump and the first cuff to open and close the flow path to the atmosphere; a pressure sensor connected to the second cuff; and a control unit that controls the pump and the on-off valve based on the pressure detected by the pressure sensor.

[0020] According to this solution, the blood pressure measurement device can drive the pump based on the pressure of the second cuff, so it can supply fluid to the second cuff until at least the second cuff reaches an appropriate pressure. In addition, when discharging the fluid of the first cuff and the second cuff, the blood pressure measurement device controls and opens the on-off valve through the control unit, thereby discharging the fluid from the first cuff and the second cuff.

[0021] A blood pressure measurement device of the above solution can be provided, which includes: a device main body that houses the pump, the on-off valve, the pressure sensor, and the control unit, and the first valve and the flow restrictor are integrated with the first cuff.

[0022] According to this solution, in the blood pressure measurement device, the control unit and the pump, on-off valve, and pressure sensor controlled by the control unit are housed in the device main body. The first valve and the flow restrictor for fluid control of the fluid circuit and not electrically connected to the control unit are integrated with the first cuff, and the first valve and the flow restrictor are not housed in the device main body. Therefore, the blood pressure measurement device can miniaturize the device main body.

[0023] According to one solution, a fluid circuit is provided, which includes: a first cuff connected to the secondary side of a pump that supplies fluid to the secondary side; a second cuff branched between the pump and the first cuff; a switching valve branched between the pump and the first cuff and provided on the primary side of the second cuff, which is closed when the pressure difference between the first cuff and the second cuff becomes a specified pressure difference; and a flow restrictor provided between the switching valve and the second cuff.

[0024] According to this solution, the fluid supplied to the secondary side by the pump is supplied to the first cuff, and when the switching valve is open, it passes through the flow restrictor and is supplied to the second cuff. Therefore, the flow rate of the air supplied to the second cuff is less than the flow rate of the air supplied to the first cuff. Therefore, the pressure of the first cuff is greater than the pressure of the second cuff. In addition, when the pressure difference between the first cuff and the second cuff becomes a specified pressure difference, the switching valve is closed, so the supply of fluid to the second cuff stops. Therefore, in the fluid circuit, the supply amount of the fluid to the second cuff is constant by the closing of the switching valve.

[0025] A fluid circuit capable of providing the above solution includes: a second valve, arranged in parallel with the flow restrictor, and opened when the pressure of the first cuff is lower than the pressure of the second cuff.

[0026] According to this solution, in the fluid circuit, when the pressure of the first cuff decreases due to discharging the fluid of the first cuff and the second cuff, etc., and the pressure of the first cuff is lower than the pressure of the second cuff, the second valve is opened. In addition, when the pressure of the first cuff is higher than the pressure of the second cuff, the fluid of the first cuff is preferentially discharged, and the fluid of the second cuff passes through the flow restrictor and is discharged. In addition, when the pressure of the first cuff is lower than the pressure of the second cuff, the second valve is opened, and the discharging speed of the fluid of the second cuff increases.

[0027] According to one solution, a blood pressure measurement device is provided, which includes: a pump for supplying fluid to the secondary side; the fluid circuit of the above solution; an on-off valve arranged between the pump and the first cuff and the switching valve for opening and closing the flow path to the atmosphere; a pressure sensor connected to the second cuff; and a control unit for controlling the pump, the switching valve, and the on-off valve based on the pressure detected by the pressure sensor.

[0028] According to this solution, the blood pressure measurement device can drive the pump based on the pressure of the second cuff, so it can supply fluid to the second cuff until at least the second cuff reaches an appropriate pressure. In addition, when discharging the fluid of the first cuff and the second cuff, the blood pressure measurement device controls and opens the on-off valve through the control unit, thereby being able to discharge the fluid from the first cuff and the second cuff.

[0029] A blood pressure measurement device capable of providing the above solution includes: a device main body for accommodating the pump, the on-off valve, the switching valve, the pressure sensor, and the control unit, and the first valve and the flow restrictor are integrated with the first cuff.

[0030] According to this solution, the pump, the on-off valve, and the pressure sensor controlled by the control unit and the controlled unit are accommodated in the device main body. The first valve and the flow restrictor for fluid control of the fluid circuit and not electrically connected to the control unit are integrated with the first cuff, and the first valve and the flow restrictor are not accommodated in the device main body. Therefore, the blood pressure measuring device can be miniaturized.

[0031] Advantages of the Invention

[0032] The present invention can provide a fluid circuit and a blood pressure measuring device capable of controlling the air injection amount into the cuff to be constant. Brief Description of the Drawings

[0033] Figure 1 It is an explanatory diagram schematically showing the configuration of the blood pressure measuring device according to the first embodiment of the present invention.

[0034] Figure 2 It is a block diagram schematically showing the configuration of the device main body of the blood pressure measuring device.

[0035] Figure 3 It is a block diagram showing the configuration of the blood pressure measuring device and showing an example of use.

[0036] Figure 4 It is a block diagram showing the configuration of the blood pressure measuring device and showing an example of use.

[0037] Figure 5 It is an explanatory diagram showing an example of the change in pressure and the change in injection amount during blood pressure measurement of the blood pressure measuring device.

[0038] Figure 6 It is an explanatory diagram showing an example of the change in pressure during exhaust after blood pressure measurement of the blood pressure measuring device.

[0039] Figure 7 It is a flowchart showing an example of the use of the blood pressure measuring device.

[0040] Figure 8 It is an explanatory diagram schematically showing the configuration of the blood pressure measuring device according to the second embodiment of the present invention.

[0041] Figure 9 It is a block diagram showing the configuration of the blood pressure measuring device and showing an example of use.

[0042] Figure 10 It is a block diagram showing the configuration of the blood pressure measuring device and showing an example of use.

[0043] Figure 11 It is a block diagram showing the configuration of the blood pressure measuring device and showing an example of use.

[0044] Figure 12 It is a perspective view showing the configuration of the blood pressure measuring device according to the third embodiment of the present invention.

[0045] Figure 13 It is a top view showing the configuration of the cuff structure and the fluid control section of the blood pressure measuring device.

[0046] Figure 14 It is an explanatory view schematically showing the configuration of the blood pressure measuring device according to the fourth embodiment of the present invention.

[0047] Figure 15 It is an explanatory view schematically showing the configuration of the blood pressure measuring device according to the fifth embodiment of the present invention.

[0048] Figure 16 It is an explanatory view schematically showing the configuration of the blood pressure measuring device according to the sixth embodiment of the present invention.

[0049] Figure 17 It is an explanatory view schematically showing the configuration of the blood pressure measuring device according to the eighth embodiment of the present invention.

[0050] Figure 18 It is an explanatory view schematically showing the configuration of the blood pressure measuring device according to the ninth embodiment of the present invention.

[0051] Figure 19 It is an explanatory view schematically showing the configuration of the blood pressure measuring device according to the tenth embodiment of the present invention. Detailed Embodiments

[0052] [First Embodiment]

[0053] Hereinafter, using Figures 1 to 7 , an example of the blood pressure measuring device 1 according to the first embodiment of the present invention is shown as follows.

[0054] Figure 1 It is an explanatory view schematically showing the configuration of the blood pressure measuring device 1 according to the first embodiment of the present invention. Figure 2 It is a block diagram schematically showing the configuration of the device main body 2 of the blood pressure measuring device 1. Figure 3 It is a block diagram showing the configuration of the blood pressure measuring device 1 and showing an example of the flow of the fluid supplied to each of the cuffs 71 and 73 during blood pressure measurement. Figure 4 It is a block diagram showing the configuration of the blood pressure measuring device 1 and showing an example of the flow of the fluid during the discharge of the fluid after blood pressure measurement. Figure 5 It is an explanatory view showing an example of the change in the pressure of each of the cuffs 71 and 73 and the change in the injection amount during blood pressure measurement of the blood pressure measuring device 1. Figure 6This is an explanatory diagram showing an example of the pressure change of each cuff 71, 73 during the discharge of the fluid after blood pressure measurement by the blood pressure measurement device 1.

[0055] The blood pressure measurement device 1 is an electronic blood pressure measurement device attached to a living body. For example, the blood pressure measurement device 1 is an electronic blood pressure measurement device attached to a living body 200 such as a wrist and having a scheme for measuring blood pressure from the artery 210 of the living body 200. As Figure 1 , Figure 3 and Figure 4 shown, the blood pressure measurement device 1 includes a device main body 2 and a fluid circuit 3. In addition, for example, as Figure 1 shown, the blood pressure measurement device 1 at least includes a fixing member 4 such as a belt for fixing the fluid circuit 3 to the living body 200. It should be noted that Figure 1 the living body 200 shown is a wrist, but the living body 200 can also be an upper arm or the like.

[0056] As Figure 2 shown, the device main body 2 includes a housing 11, a display device 12, an operation device 13, a pump 14, a flow path section 15, an on-off valve 16, a pressure sensor 17, a power supply section 18, a communication device 19, and a control board 20.

[0057] The housing 11 houses, for example, the display device 12, the operation device 13, the pump 14, the flow path section 15, the on-off valve 16, the pressure sensor 17, the power supply section 18, the communication device 19, and the control board 20. In addition, the housing 11 exposes a part of the display device 12 in a manner that allows it to be visually confirmed from the outside or is formed of a transparent material. It should be noted that the housing 11 can also be a part of the configuration that houses a part of the configuration of the fluid circuit 3.

[0058] The display device 12 is electrically connected to the control board 20. The display device 12 is, for example, a liquid crystal display (LCD: Liquid Crystal Display) or an organic electro-luminescence display (OELD: Organic Electro Luminescence Display). The display device 12 displays various information including blood pressure values such as date, maximum blood pressure, and minimum blood pressure, and measurement results such as heart rate according to a control signal from the control board 20.

[0059] The operation device 13 inputs instructions from the user. For example, the operation device 13 is a sensor including a plurality of buttons and detecting button operations, a touch panel such as a pressure-sensitive type or a capacitive type provided on the housing 11, the display device 12, etc., a microphone for receiving voice-based instructions, etc. The operation device 13 converts the instructions into an electrical signal by the user's operation and outputs the electrical signal to the control board 20.

[0060] The pump 14 is a piezoelectric pump, for example. The pump 14 compresses the fluid and supplies the compressed fluid to the fluid circuit 3 via the flow path section 15. The pump 14 is electrically connected to the control substrate 20. The pump 14 is driven based on the control signal provided from the control substrate 20. Here, the fluid can be any gas or any liquid. In the present embodiment, the fluid is air.

[0061] The flow path section 15 connects the pump 14, the on-off valve 16, and the pressure sensor 17 to the fluid circuit 3. The flow path section 15 is any one of a tube, a pipe, a tank, and a hollow portion and a groove formed in the housing 11, or a combination thereof. As a specific example, the flow path section 15 forms a flow path to the secondary side from the pump 14, and forms a flow path 15a that branches a part of the flow path to the secondary side from the pump 14 and connects to the on-off valve 16. In addition, the flow path section 15 forms a flow path 15b that connects the on-off valve 16 to the atmosphere. In addition, the flow path section 15 forms a flow path 15c that connects the pressure sensor 17 to the fluid circuit 3.

[0062] The on-off valve 16 is electrically connected to the control substrate 20. The on-off valve 16 is controlled by the control substrate 20. For example, the on-off valve 16 is opened and closed by the control of the control substrate 20. The on-off valve 16 is connected to the atmosphere through the flow path section 15, and when switched to the open state, connects the pump 14 and the fluid circuit 3 to the atmosphere.

[0063] The on-off valve 16 is an exhaust valve that opens the flow path on the secondary side of the pump 14 to the atmosphere. In addition, for example, the on-off valve 16 is a rapid exhaust valve that is set so that the opening degree of the on-off valve 16 or the opening area of the flow path section 15 minimizes the fluid resistance as much as possible and enables rapid exhaust. It should be noted that in each figure, the on-off valve 16 is shown as the rapid exhaust valve 16. When air is supplied to the fluid circuit 3 during blood pressure measurement, such an on-off valve 16 is switched to the closed state. In addition, when the fluid circuit 3 is exhausted, the on-off valve 16 is switched from the closed state to the open state by being controlled by the control substrate 20. In addition, the on-off valve 16 can also be formed to be able to adjust the opening degree.

[0064] The pressure sensor 17 detects the pressure of the cuff disposed on the secondary side of the fluid circuit 3, and detects the pressure of the sensing cuff 73 described later in the fluid circuit 3 in the present embodiment. As a specific example, the pressure sensor 17 is fluidly connected to the sensing cuff 73 via the flow path section 15 and detects the pressure inside the sensing cuff 73. The pressure sensor 17 is electrically connected to the control substrate 20. The pressure sensor 17 outputs an electrical signal corresponding to the detected pressure to the control substrate 20.

[0065] The power supply unit 18 serves as the 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. As a specific example, 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 operation device 13, the pump 14, the on-off valve 16, the pressure sensor 17, and the communication device 19.

[0066] The communication device 19 is configured to be able to transmit and receive information with an external device wirelessly or wiredly. The communication device 19, for example, transmits information controlled by the control board 20, measured blood pressure values, pulse, and other information to an external device. In addition, it receives programs for software updates and the like from an external device and transmits them to the control unit.

[0067] In the present embodiment, the external device is, for example, an external terminal such as a smartphone, a tablet terminal, a personal computer, or a smartwatch.

[0068] In the present embodiment, the communication device 19 may be directly connected to the external device or may be connected via a network. The communication device 19 may be connected to the external device via a wireless communication line such as a 4G or 5G mobile communication network, WiMAX, or Wi-Fi (registered trademark). In addition, the communication device 19 may be connected to the external device through a wireless communication unit such as Bluetooth (registered trademark), near field communication (NFC: Near Field Communication), or infrared communication. Moreover, the communication device 19 may be connected to the external device via a wired communication line such as a universal serial bus (USB: Universal Serial Bus) or a cable-based local area network (LAN: Local Area Network) connection. Therefore, the communication device 19 may also be configured to include multiple communication units such as a wireless antenna and a micro-USB connector.

[0069] The control board 20, for example, includes a board 51, a storage unit 54, and a control unit 55. The control board 20 is constituted by mounting the storage unit 54 and the control unit 55 on the board 51.

[0070] The board 41 is fixed to the housing 11.

[0071] The storage unit 54 is a memory installed on the substrate 51. The storage unit 54 includes a random access memory (RAM) and a read only memory (ROM), etc. The storage unit 54 stores various data. For example, the storage unit 54 pre-stores program data for controlling the entire blood pressure measuring device 1, the pump 14, and the fluid circuit 3, setting data for setting various functions of the blood pressure measuring device 1, and calculation data for calculating blood pressure values, pulse rates, etc. based on the pressure measured by the pressure sensor 17 in a changeable manner. The storage unit 54 stores measured values such as blood pressure values and pulse rates, and information such as pressure values measured by the pressure sensor 17. The storage unit 54 can also store various data generated by the measurement processing unit 55a of the control unit 55.

[0072] The control unit 55 includes one or more processors installed on the substrate 51. The processor is, for example, a central processing unit (CPU). The control unit 55 controls the operations of the entire blood pressure measuring device 1, the pump 14, and the fluid circuit 3 based on the programs stored in the storage unit 54, and executes specified operations (functions). In addition, the control unit 55 performs specified operations, analysis, processing, etc. within the control unit 55 according to the read programs.

[0073] The control unit 55 is electrically connected to the display device 12, the operation device 13, the pump 14, the on-off valve 16, and each pressure sensor 17, and supplies power. In addition, the control unit 55 controls the operations of the display device 12, the pump 14, and the on-off valve 16 based on the electrical signals output by the operation device 13 and the pressure sensor 17.

[0074] For example, the control unit 55 includes a main CPU that controls the operations of the entire blood pressure measuring device 1 and a sub-CPU that controls the operations of the fluid circuit 3. It should be noted that, for example, the control unit 55 may also be configured to perform all controls of the blood pressure measuring device 1 through one CPU. In addition, for example, the main CPU obtains blood pressure values such as systolic blood pressure and diastolic blood pressure, and measurement results such as heart rate based on the electrical signals output by the pressure sensor 17, and outputs an image signal corresponding to the measurement results to the display device 12.

[0075] For example, when an instruction to measure blood pressure is input from the operation device 13, the sub-CPU drives the pump 14 and the on-off valve 16 to deliver compressed air to the fluid circuit 3. In addition, the sub-CPU controls the driving and stopping of the pump 14 and the opening and closing of the on-off valve 16 based on the electrical signals output by the pressure sensor 17. The sub-CPU supplies compressed air to the fluid circuit 3 by controlling the pump 14 and the on-off valve 16, and selectively decompresses the fluid circuit 3.

[0076] Such a control unit 55 is configured, in terms of hardware, by one or more integrated circuits or the like to form part or all of each function executed by the control unit 55. For example, the control unit 55 includes a measurement processing unit 55a. The measurement processing unit 55a controls, for example, the pump 14 and the on-off valve 16 to supply air to the fluid circuit 3, and calculates the blood pressure by the oscillometric method based on the pressure of a sensing cuff 73 (described later) of the fluid circuit 3 detected by the pressure sensor 17.

[0077] The fluid circuit 3 includes a cuff structure 6, a tube set 7, and a fluid control unit 9. The fluid circuit 3 fluidly connects the cuff structure 6 and the fluid control unit 9 through the tube set 7.

[0078] It should be noted that when air is supplied from the pump 14 to the fluid circuit 3, in the air flow, the pump 14 side (device main body 2 side) becomes the primary side, and the fluid circuit 3 side becomes the secondary side. However, when exhausting air, the on-off valve 16 side (device main body 2 side) becomes the secondary side, and the fluid circuit 3 side becomes the primary side. However, in the description of the configuration of the fluid circuit 3, for the sake of convenience of explanation, the primary side and the secondary side are defined based on the air flow direction when air is supplied from the pump 14 to the cuff structure 6 and the tube set 7.

[0079] The cuff structure 6 includes a plurality of cuffs. Here, a cuff includes a one-layer or multi-layer bag-shaped structure that is wound around a living body's wrist or the like during blood pressure measurement and expands by being supplied with fluid. The bag-shaped structure expands by fluid. In the present embodiment, since the fluid is air, the bag-shaped structure is an air bag. The bag-shaped structure is formed, for example, by overlapping and welding a pair of sheet members.

[0080] For example, the cuff structure 6 includes a first cuff 71 and a second cuff 73. The first cuff 71 is fluidly connected to the pump 14. The first cuff 71 expands by air from the pump 14. The first cuff 71 is a pressing cuff that presses the second cuff 73 against the living body by expanding. Hereinafter, the first cuff 71 will be described as the pressing cuff 71. The pressing cuff 71 is formed, for example, by laminating a plurality of fluidly connected air bags in the pressing direction of the second cuff 73.

[0081] The second cuff 73 is provided on the secondary side of the first cuff 71. The second cuff 73 is inflated by air from the pump 14. When the blood pressure measuring device 1 is attached to a living body, the second cuff 73 is disposed in the region of the living body 200 where the artery 210 exists. The second cuff 73 is a sensing cuff used for calculating blood pressure during blood pressure measurement. Hereinafter, the second cuff 73 will be described as the sensing cuff 73. The sensing cuff 73 compresses the region of the living body 200 where the artery 210 exists by inflation. The sensing cuff 73 is pressed toward the living body 200 by the inflated pressing cuff 71. The sensing cuff 73 is formed of, for example, a single air bag. The sensing cuff 73 is fluidly connected to the pressing cuff 71 via the fluid control unit 9. In the present embodiment, an example in which the sensing cuff 73 is fluidly connected to the secondary side of the pressing cuff 71 via the fluid control unit 9 will be described.

[0082] The tube group 7 is a collection of tubes, hollow portions provided between sheet members constituting the air bag, and the like. The tube group 7 is, for example, integrated with the cuff structure 6, and may also be provided separately from the cuff structure 6 and connected to the cuff structure 6.

[0083] The tube group 7 fluidly connects the pressing cuff 71, the sensing cuff 73, and the fluid control unit 9. In addition, the tube group 7 is connected to the flow path unit 15. In the present embodiment, an example of the tube group 7 having a configuration in which the fluid control unit 9 includes the first valve 21, the flow blocking member 22, and the second valve 23 will be described.

[0084] The tube group 7 fluidly connects the pump 14 and the on-off valve 16 to the pressing cuff 71 via the flow path unit 15, for example. The tube group 7 fluidly connects the pressure sensor 17 to the sensing cuff 73 via the flow path unit 15, for example. In addition, the tube group 7 fluidly connects the first valve 21, the flow blocking member 22, and the sensing cuff 73 to the secondary side of the pressing cuff 71 in series, and fluidly connects the first valve 21 and the flow blocking member 22 to the second valve 23 in parallel.

[0085] Specifically, the tube group 7 includes a first tube 7a, a second tube 7b, a third tube 7c, a fourth tube 7d, and a fifth tube 7e. The first tube 7a is connected to the flow path 15a of the flow path unit 15 and the pressing cuff 71. The first tube 7a connects the pump 14 and the on-off valve 16 to the pressing cuff 71 via the flow path unit 15.

[0086] The second tube 7b is a branch tube having a branch portion 7b1 in the middle portion from the primary side toward the secondary side and branching into two flow paths at the branch portion 7b1. The primary side of the second tube 7b is fluidly connected to the pressing cuff 71. One branched tube portion 7b2 located on the secondary side of the second tube 7b is connected to the first valve 21. The other branched tube portion 7b3 located on the secondary side of the second tube 7b is connected to the second valve 23.

[0087] The third tube 7c is connected to the first valve 21 and the flow restrictor 22. The fourth tube 7d is a confluence tube having a confluence portion 7d1 that merges two flow paths into one flow path in the middle portion from the primary side toward the secondary side. One tube portion 7d2 of the fourth tube 7d on the primary side relative to the confluence portion 7d1 is connected to the flow restrictor 22. The other tube portion 7d3 of the fourth tube 7d on the primary side relative to the confluence portion 7d1 is connected to the second valve 23. The secondary side of the fourth tube 7d is connected to the sensing cuff 73.

[0088] The fifth tube 7e is connected to the flow path 15c of the flow path portion 15 and the sensing cuff 73. The fifth tube 7e connects the pressure sensor 17 to the sensing cuff 73 via the flow path portion 15.

[0089] The fluid control unit 9 controls the flow rate of air to reduce the flow rate of air flowing from the primary side to the secondary side, and controls the injection amount of the cuff on the secondary side to be constant by restricting the flow of air at a specified injection amount. The fluid control unit 9 controls the pressure on the primary side and the pressure on the secondary side of the fluid control unit 9.

[0090] As a specific example, the fluid control unit 9 reduces the flow rate of air flowing from the pressing cuff 71 side to the sensing cuff 73, and stops the supply of air to the sensing cuff 73 at a specified injection amount. Then, the fluid control unit 9 controls the injection amount of the air supplied to the sensing cuff 73 to be constant with the injection amount of air into the sensing cuff 73 being the specified injection amount, and controls the pressures of the pressing cuff 71 and the sensing cuff 73. The fluid control unit 9 includes, for example, the first valve 21, the flow restrictor 22, and the second valve 23.

[0091] The first valve 21 closes when the pressure on the primary side is higher than the pressure on the secondary side by a specified pressure. Specifically, the first valve 21 closes when the pressure on the pressing cuff 71 side becomes a specified pressure or higher compared to the pressure on the sensing cuff 73 side. Such a first valve 21 is, for example, always open and closes when the pressure difference between the pressure of the pressing cuff 71 and the pressure of the sensing cuff 73 becomes the opening pressure that is higher than the specified pressure. The first valve 21 is, for example, a one-way valve. In each figure, the first valve 21 is shown as the first one-way valve 21.

[0092] For example, the opening pressure of the first valve 21 is set to a pressure suitable for blood pressure measurement using the pressing cuff 71 and the sensing cuff 73. As a specific example, the opening pressure of the first valve 21 is set to 70 mmHg so that the first valve 21 closes when the pressure of the pressing cuff 71 becomes 100 mmHg and the pressure of the sensing cuff 73 becomes 30 mmHg.

[0093] The flow restrictor 22 creates resistance to the fluid passing through it, which is air resistance in this embodiment. The flow restrictor 22 has, for example, a flow path cross-sectional area smaller than the flow path cross-sectional areas of the primary side and the secondary side of the flow restrictor 22, that is, smaller than the flow path cross-sectional areas of the third tube 7c and the fourth tube 7d. The flow restrictor 22 is, for example, a throttling element. The flow restrictor 22 reduces the flow path partially on the primary side of the sensing cuff 73 to make the amount of air injected into the sensing cuff 73 less than the amount of air injected into the pressing cuff 71 that has been supplied. The resistance value of the flow restrictor 22 is set to a value such that the amounts of air injected into the pressing cuff 71 and the sensing cuff 73 are set to the preferred amounts and the pressures of the pressing cuff 71 and the sensing cuff 73 become the desired pressures. For example, as described above, the flow restrictor 22 is set to a resistance value such that when the pressure of the pressing cuff 71 is 100 mmHg, the pressure of the sensing cuff 73 becomes 30 mmHg.

[0094] The second valve 23 opens when the pressure on the primary side is lower than the pressure on the secondary side. Specifically, the second valve 23 closes when the pressure on the pressing cuff 71 side is equal to or higher than the pressure on the sensing cuff 73 side, and opens when the pressure on the pressing cuff 71 side is lower than the pressure on the sensing cuff 73 side. Such a second valve 23, for example, remains closed all the time when supplying air to the pressing cuff 71 and the sensing cuff 73 during blood pressure measurement. In addition, the second valve 23 opens when the pressure difference between the pressure of the pressing cuff 71 and the pressure of the sensing cuff 73 disappears during exhaust and becomes the opening pressure at which the pressure of the pressing cuff 71 is lower than the pressure of the sensing cuff 73. The second valve 23 is, for example, a one-way valve. In each figure, the second valve 23 is shown as the second one-way valve 23.

[0095] For example, the opening pressure of the second valve 23 is set to a pressure suitable for exhausting the pressing cuff 71 and the sensing cuff 73. As a specific example, the opening pressure of the second valve 23 is set to 0 mmHg so that the second valve 23 opens when the pressure of the pressing cuff 71 is lower than the pressure of the sensing cuff 73.

[0096] It should be noted that the second valve 23 is configured to open when the pressure on the primary side is lower than the pressure on the secondary side so as to prevent the air in the pressing cuff 71 from flowing to the sensing cuff 73 side during exhaust. However, as long as the air does not substantially flow from the pressing cuff 71 to the sensing cuff 73 during the exhaust of the fluid circuit 3, the second valve 23 can also be set to an opening pressure at which it opens when the pressure on the primary side is slightly higher than the pressure on the secondary side.

[0097] Next, use Figure 3 and Figure 5 , to illustrate an example of the changes in the pressures of the pressing cuff 71 and the sensing cuff 73 and the amount of air injected when air is supplied to such a fluid circuit 3. In Figure 3In the figure, the flow of air is indicated by arrows, and the flow paths closed by each valve are indicated by X. In addition, in Figure 5 an example of the open state and the closed state of the first valve 21 is shown.

[0098] In the fluid circuit 3, when the on-off valve 16 is closed and the driving of the pump 14 is started by the measurement processing unit 55a of the control unit 55 during blood pressure measurement, first, air is supplied to the pressure cuff 71. At this time, the first valve 21 is open. In addition, since the air is first supplied to the pressure cuff 71, the second valve 23 is closed. Therefore, the air supplied to the pressure cuff 71 is supplied to the sensing cuff 73 via the first valve 21 and the flow restrictor 22. At this time, since the air supplied to the sensing cuff 73 passes through the flow restrictor 22, as Figure 5 shown, the amount of air injected into the sensing cuff 73 is less than the amount of air injected into the pressure cuff 71. Therefore, the pressure increases of the pressure cuff 71 and the sensing cuff 73 are also different, and the pressure cuff 71 and the sensing cuff 73 are pressurized in such a way that the pressure of the pressure cuff 71 is maintained higher than the pressure of the sensing cuff 73.

[0099] Then, when the pressure difference between the pressure cuff 71 and the sensing cuff 73 reaches the opening pressure of the first valve 21, the first valve 21 closes. When the first valve 21 becomes the closed state, the air supplied by the pump 14 thereafter is only supplied to the pressure cuff 71. Therefore, as Figure 5 shown, after the first valve 21 closes, the amount of air injected into the pressure cuff 71 increases, but the amount of air injected into the sensing cuff 73 does not increase and remains constant at the amount when the first valve 21 is closed. It should be noted that the sensing cuff 73 is pressed against the living body 200 by the inflated pressure cuff 71. Therefore, although the amount of air injected into the sensing cuff 73 does not change, the pressure of the sensing cuff 73 increases. Thus, during blood pressure measurement, the pressures of the pressure cuff 71 and the sensing cuff 73 increase to a pressure suitable for blood pressure measurement.

[0100] Next, an example of the pressure changes of the pressure cuff 71 and the sensing cuff 73 when the air supplied to the fluid circuit 3 is discharged is described using Figure 4 and Figure 6 . In Figure 4 the figure, the flow of air is indicated by arrows. In addition, in Figure 6 an example of the open state and the closed state of the second valve 23 is shown.

[0101] In the fluid circuit 3, when the exhaust of the fluid circuit 3 starts after blood pressure measurement, the pump 14 stops and the on-off valve 16 is opened by the measurement processing unit 55a of the control unit 55. Therefore, the side of the on-off valve 16 of the pressure cuff 71 is connected to the atmosphere. As a result, the air in the pressure cuff 71 flows toward the on-off valve 16 side, and the pressure of the pressure cuff 71 decreases. It should be noted that at this time, the first valve 21 and the second valve 23 are closed.

[0102] When the exhaust of the pressure cuff 71 is in progress, the pressure of the pressure cuff 71 decreases. Therefore, as Figure 6 shown, the pressing force of the sensing cuff 73 generated by the pressure cuff 71 decreases, and the pressure of the sensing cuff 73 also decreases. When the exhaust of the pressure cuff 71 is in progress and the pressure difference between the pressure cuff 71 and the sensing cuff 73 is lower than the opening pressure of the first valve 21, the first valve 21 opens. As a result, the air in the sensing cuff 73 flows toward the on-off valve 16 side via the flow restrictor 22 and the pressure cuff 71. It should be noted that the exhaust volume of the air discharged from the sensing cuff 73 is reduced by the flow restrictor 22 and is smaller than the exhaust volume of the air in the pressure cuff 71.

[0103] Then, when the pressure of the pressure cuff 71 further decreases and becomes lower than the pressure of the sensing cuff 73, as Figure 6 shown, the second valve 23 is switched from the closed state to the open state. When the second valve 23 opens, the flow path passing through the second valve 23 becomes a bypass path, and the exhaust speed of the sensing cuff 73 increases. And the exhaust of the pressure cuff 71 and the sensing cuff 73 is in progress, and the pressures of the pressure cuff 71 and the sensing cuff 73 become atmospheric pressure. In this way, in the exhaust of the fluid circuit 3, the pressure cuff 71 is exhausted rapidly prior to the sensing cuff 73. Then, in the fluid circuit 3, when the pressure of the pressure cuff 71 is lower than the pressure of the sensing cuff 73, the second valve 23 opens, and the pressure cuff 71 and the sensing cuff 73 are exhausted rapidly. In this way, the exhaust of the fluid circuit 3 is performed.

[0104] Next, an example of the control during blood pressure measurement using the blood pressure measurement device 1 configured as described above will be described using the Figure 7 flowchart shown.

[0105] First, with the blood pressure measurement device 1 attached to the living body 200, the user operates the operation device 13 to give an instruction to start blood pressure measurement. The operation device 13 outputs an electrical signal to the control unit 55 as an instruction to start blood pressure measurement. When the control unit 55 receives the electrical signal from the operation device 13, the measurement processing unit 55a switches the on-off valve 16 to the closed state, starts driving the pump 14, and pressurizes the compression cuff 71 and the sensing cuff 73 (step ST101). Then, the measurement processing unit 55a determines whether the pressure measured by the pressure sensor 17 is a specified pressure (step ST102). Here, the specified pressure is the pressure of the sensing cuff 73 at which blood pressure can be measured by the sensing cuff 73, and is pre-stored in the storage unit 54.

[0106] When the pressure of the sensing cuff 73 is not the specified pressure (No in step ST102), the measurement processing unit 55a continues to drive the pump 14. When the pressure of the sensing cuff 73 reaches the specified pressure (Yes in step ST102), the measurement processing unit 55a stops the pump 14 and stops supplying air to the compression cuff 71. In addition, the measurement processing unit 55a switches the on-off valve 16 to the open state to start decompressing the compression cuff 71 (step ST103). At this time, the measurement processing unit 55a slowly decompresses the compression cuff 71 by adjusting the opening degree of the on-off valve 16 or repeatedly switching the opening and closing of the on-off valve 16.

[0107] The measurement processing unit 55a calculates a blood pressure value based on the pressure measured by the pressure sensor 17 (step ST104). Next, the measurement processing unit 55a determines whether the calculated value can be determined as the blood pressure value (step ST105). It should be noted that the threshold value for determining whether the calculated value can be determined as the blood pressure value is pre-stored in the storage unit 54. In addition, the threshold value for determining the blood pressure value is appropriately set according to the detected blood pressure value, the pressure of the sensing cuff 73, etc. When the calculated value cannot be determined as the blood pressure value (No in step ST105), the measurement processing unit 55a continues to decompress the compression cuff 71 (step ST103). When the calculated value is determined as the blood pressure value (Yes in step ST105), the measurement processing unit 55a displays the blood pressure value on the display device 12 (step ST106), and records (stores) the measured blood pressure value in the storage unit 54 (step ST107). Next, the measurement processing unit 55a sets the opening degree of the on-off valve 16 to the maximum or sets the on-off valve 16 to the open state, and exhausts the compression cuff 71 and the sensing cuff 73 (step ST108). Then, the measurement processing unit 55a ends the blood pressure measurement, waits until the next instruction to start blood pressure measurement is received, and when the instruction to start blood pressure measurement is received, returns to step ST101 again to start blood pressure measurement.

[0108] According to the blood pressure measuring device 1 configured as such, the fluid circuit 3 includes, as a fluid control unit 9, a first valve 21 that closes when the opening pressure is reached between the pressure cuff 71 and the sensing cuff 73, and a flow restrictor 22 that reduces the flow of air to the secondary side. Therefore, when air is supplied to the pressure cuff 71 and the sensing cuff 73 by the pump 14, a pressure difference is generated between the pressure cuff 71 and the sensing cuff 73. And when the pressure difference reaches the opening pressure of the first valve 21, the first valve 21 closes. Thus, the fluid control unit 9 can supply a specified injection volume of air to the sensing cuff 73. Therefore, during blood pressure measurement, there is no need for the air injection process by the measurement processing unit 55a of the control unit 55, and the blood pressure measurement time is shortened. As a result, the influence of body movement and other artifacts is eliminated, and the robustness during actual use of the blood pressure measuring device 1 is improved.

[0109] In addition, the injection volume and the pressure difference of the air in the pressure cuff 71 and the sensing cuff 73 can be set by the opening pressure of the first valve 21 and the resistance value of the flow restrictor 22. Therefore, the first valve 21 and the flow restrictor 22 can make the injection volume of the air in the sensing cuff 73 constant. That is, the fluid control unit 9 controls the flow rate of the air supplied to the secondary side by the supplied fluid. Thus, the blood pressure measuring device 1 does not require electrically controlled components such as the control unit 55 other than the pump 14 and the on-off valve 16 to make the injection volume of the sensing cuff 73 constant at a desired injection volume. Therefore, the blood pressure measuring device 1 can simplify the control during blood pressure measurement and can reduce power consumption. In addition, since the first valve 21 that does not require electrical control, the flow restrictor 22, and the second valve 23 do not need to be arranged in the device main body 2, by arranging the fluid control unit 9 outside the device main body 2, the device main body 2 can be miniaturized.

[0110] In addition, when the flow restrictor 22 is provided, when the air in the fluid circuit 3 is exhausted and the air flows from the sensing cuff 73 through the pressure cuff 71 to the atmosphere, the flow of the air is obstructed and the exhaust speed decreases. However, the blood pressure measuring device 1 is provided with a second valve 23 that opens when the pressure of the pressure cuff 71 is lower than the pressure of the sensing cuff 73 in parallel with the flow path passing through the first valve 21 and the flow restrictor 22. Therefore, the air in the sensing cuff 73 is discharged to the atmosphere through the pressure cuff 71 not only through the flow path passing through the flow restrictor 22 and the first valve 21 but also through the bypass path passing through the second valve 23. Thus, even with the configuration in which the flow restrictor 22 is provided, it is possible to prevent the exhaust speed of the sensing cuff 73 from decreasing. In addition, the pressure cuff 71 that presses the living body 200 more is preferentially exhausted. When the pressure of the pressure cuff 71 is lower than that of the sensing cuff 73, the exhaust speed of the sensing cuff 73 increases. Therefore, the blood pressure measuring device 1 can reduce the load on the living body 200 caused by the compression after blood pressure measurement and can shorten the exhaust time of the sensing cuff 73.

[0111] As described above, in the blood pressure measurement device 1 according to the first embodiment, a sensing cuff 73 is provided on the secondary side of the pressing cuff 71, and a first valve 21 and a flow blocking member 22 that are closed by the pressure difference between the pressing cuff 71 and the sensing cuff 73 are provided between the pressing cuff 71 and the sensing cuff 73. Therefore, the blood pressure measurement device 1 can control the amount of air injected into the sensing cuff 73 to be constant.

[0112] [Second Embodiment]

[0113] Next, Figures 8 to 11 will be used to describe the blood pressure measurement device 1A of the second embodiment.

[0114] Figure 8 is an explanatory diagram schematically showing the configuration of the blood pressure measurement device 1A of the second embodiment. Figure 9 and Figure 10 is a block diagram showing the configuration of the blood pressure measurement device 1A and an example of the flow of the fluid supplied to each cuff 71, 73 during blood pressure measurement. Figure 11 is a block diagram showing the configuration of the blood pressure measurement device 1 and an example of the flow of the fluid during the discharge of the fluid after blood pressure measurement. It should be noted that the same reference numerals are given to the same configurations in the blood pressure measurement device 1A of the second embodiment as those in the blood pressure measurement device 1 of the first embodiment, and the detailed description thereof is omitted.

[0115] As Figure 8 shown, the blood pressure measurement device 1A is an electronic blood pressure measurement device attached to the living body 200, the same as the blood pressure measurement device 1. As Figures 8 to 11 shown, the blood pressure measurement devices 1, 1A include a device main body 2A and a fluid circuit 3A.

[0116] The device main body 2A includes a housing 11, a display device 12, an operation device 13, a pump 14, a flow path section 15, a first on-off valve (on-off valve) 16, a pressure sensor 17, a power supply section 18, a communication device 19, a control board 20, and a second on-off valve 21A that realizes the same function as the first valve through electrical on-off. That is, the device main body 2A is different from the device main body 2 of the above-described first embodiment in that it has a second on-off valve 21A with electrical on-off as the first valve 21A and a flow path 15a of the flow path section 15 for connecting the second on-off valve 21A.

[0117] The housing 11 houses, for example, the display device 12, the operation device 13, the pump 14, the flow path section 15, the first on-off valve 16, the pressure sensor 17, the power supply section 18, the communication device 19, the control board 20, and the second on-off valve 21A.

[0118] The flow path 15a of the flow path section 15 forms a flow path from the pump 14 to the secondary side, and branches the flow path from the pump 14 to the secondary side into three directions to connect to the pressure cuff 71, the first on-off valve 16, and the second on-off valve 21A.

[0119] The second on-off valve 21A is a switching valve that is controlled by the control unit 55 (measurement processing unit 55a) to switch the opening and closing of the flow path. The second on-off valve 21A is electrically connected to the control board 20. The second on-off valve 21A is controlled by the control board 20. For example, the second on-off valve 21A is opened and closed by the control of the control board 20. The second on-off valve 21A is connected to the flow restrictor 22 and the second valve 23 of the fluid circuit 3A.

[0120] When supplying air to the pressure cuff 71 and the sensing cuff 73 during blood pressure measurement, the second on-off valve 21A switches to the open state, thereby connecting the pump 14 to the flow restrictor 22. That is, the second on-off valve 21A and the flow restrictor 22 constitute the fluid control unit 9A. In addition, the second on-off valve 21A switches to the open state during exhaust, thereby connecting the pump 14 to the sensing cuff 73 and connecting the sensing cuff 73 to the atmosphere.

[0121] Such a second on-off valve 21A is different from the above-described first valve 21 that closes at the opening pressure in terms of the configuration of being opened and closed by the control unit 55, but in terms of generating the function of the fluid control unit 9A, it has the same effect as the first valve 21.

[0122] For example, the storage unit 54 stores in a changeable manner program data for controlling the entire blood pressure measurement device 1A, the pump 14, the second on-off valve 21A, and the fluid circuit 3A, setting data for setting various functions of the blood pressure measurement device 1A, calculation data for calculating blood pressure values and pulse rates based on the pressure measured by the pressure sensor 17, and the like.

[0123] The control unit 55 controls the operations of the entire blood pressure measurement device 1A, the pump 14, the second on-off valve 21A, and the fluid circuit 3A based on the programs stored in the storage unit 54, and executes prescribed operations (functions). The control unit 55 is electrically connected to the display device 12, the operation device 13, the pump 14, the on-off valve 16, the pressure sensor 17, and the second on-off valve 21A, and supplies power. In addition, the control unit 55 controls the operations of the display device 12, the pump 14, the on-off valve 16, and the second on-off valve 21A based on the electrical signals output from the operation device 13 and the pressure sensor 17.

[0124] For example, when an instruction to measure blood pressure is input from the operation device 13, the sub-CPU of the control unit 55 drives the pump 14, the on-off valve 16, and the second on-off valve 21A to supply compressed air to the fluid circuit 3A. In addition, the sub-CPU controls the driving and stopping of the pump 14, the opening and closing of the on-off valve 16, and the opening and closing of the second on-off valve 21A based on the electrical signal output by the pressure sensor 17. The sub-CPU supplies compressed air to the fluid circuit 3A by controlling the pump 14, the on-off valve 16, and the second on-off valve 21A, and selectively decompresses the fluid circuit 3A.

[0125] The measurement processing unit 55a of such a control unit 55 controls, for example, the pump 14, the on-off valve 16, and the second on-off valve 21A to supply air to the fluid circuit 3A, and calculates the blood pressure by the oscillometric method based on the pressure of the sensing cuff 73 detected by the pressure sensor 17.

[0126] The fluid circuit 3A includes a cuff structure 6, a tube set 7, a flow restrictor 22, and a second valve 23. The flow restrictor 22 and the second valve 23 of the fluid circuit 3A together with the second on-off valve 21A form a fluid control unit 9A. The fluid circuit 3A fluidly connects the cuff structure 6, the flow restrictor 22, and the second valve 23 through the tube set 7. Such a fluid circuit 3A is configured without the first valve 21 of the fluid circuit 3 of the blood pressure measurement device 1 in the above-described first embodiment.

[0127] In addition, the primary side of the second tube 7b of the tube set 7 is fluidly connected to the second on-off valve 21A. One branched tube portion 7b2 located on the secondary side of the second tube 7b is connected to the flow restrictor 22. The tube portion 7b2 also serves as the tube 7c. The other branched tube portion 7b3 located on the secondary side of the second tube 7b is connected to the second valve 23.

[0128] Such a second on-off valve 21A and the fluid circuit 3A exhibit the same functional effects as the above-described fluid circuit 3. Specifically, as Figure 9 shown, when the supply of air is started by the pump 14 during blood pressure measurement, the air is supplied to the pressing cuff 71. In addition, when the driving of the pump 14 starts, the measurement processing unit 55a of the control unit 55 sets the second on-off valve 21A to the open state. The second on-off valve 21A is in the open state, and in addition, the second valve 23 is closed. Therefore, as Figure 9 indicated by the arrow in, the air is supplied not only to the pressing cuff 71 but also to the sensing cuff 73 via the flow restrictor 22. At this time, as Figure 5 shown, since the air supplied to the sensing cuff 73 passes through the flow restrictor 22, the injection amount of air into the sensing cuff 73 is less than the injection amount of air into the pressing cuff 71. Therefore, as Figure 5As shown, the pressure increases of the pressing cuff 71 and the sensing cuff 73 are also different, and the pressing cuff 71 and the sensing cuff 73 are pressurized in such a way that the pressure of the pressing cuff 71 is maintained higher than the pressure of the sensing cuff 73.

[0129] Then, when the pressure of the sensing cuff 73 reaches the desired pressure, the measurement processing unit 55a determines that the pressure difference between the pressure of the pressing cuff 71 and the pressure of the sensing cuff 73 has reached the specified pressure difference. The measurement processing unit 55a controls the second on-off valve 21A to close the second on-off valve 21A. As Figure 10 shown by the arrow in, after the second on-off valve 21A is closed, the air supplied by the pump 14 is only supplied to the pressing cuff 71. Therefore, as Figure 5 shown, after the second on-off valve 21A is closed, the injection amount of air into the pressing cuff 71 increases, but the injection amount of air into the sensing cuff 73 does not increase. It should be noted that the sensing cuff 73 is pressed against the living body 200 by the expanded pressing cuff 71. Therefore, although the injection amount of air into the sensing cuff 73 does not change, the pressure of the sensing cuff 73 increases. In this way, when air is supplied to the pressing cuff 71 and the sensing cuff 73 during blood pressure measurement, the pressures of the pressing cuff 71 and the sensing cuff 73 increase to the pressures suitable for blood pressure measurement.

[0130] In addition, when the exhaust of the fluid circuit 3A starts after blood pressure measurement, the first on-off valve 16 is opened by the measurement processing unit 55a, and the side of the first on-off valve 16 of the pressing cuff 71 is connected to the atmosphere. Therefore, as Figure 11 shown, the air in the pressing cuff 71 flows to the side of the first on-off valve 16. When the exhaust of the pressing cuff 71 is performed, the pressure of the pressing cuff 71 decreases.

[0131] In addition, the measurement processing unit 55a opens the second on-off valve 21A while opening the first on-off valve 16. As a result, the air in the sensing cuff 73 flows to the side of the first on-off valve 16 via the flow restrictor 22 and the second on-off valve 21A. It should be noted that the exhaust amount of the air discharged from the sensing cuff 73 is reduced by the flow restrictor 22 and is smaller than the exhaust amount of the air in the pressing cuff 71.

[0132] Then, when the pressure of the pressing cuff 71 decreases and becomes lower than the pressure of the sensing cuff 73, as Figure 11 shown, the second valve 23 opens, and as Figure 6 shown, the rapid exhaust of the sensing cuff 73 starts. And the exhaust of the pressing cuff 71 and the sensing cuff 73 is performed, and the pressures of the pressing cuff 71 and the sensing cuff 73 become the atmospheric pressure. In this way, the exhaust of the fluid circuit 3A is performed.

[0133] It should be noted that an example of the control during blood pressure measurement using the blood pressure measurement device 1A configured as described above is through Figure 7It is performed according to the same process as an example of the control of the blood pressure measuring device 1 of the above-described first embodiment.

[0134] According to the blood pressure measuring device 1A configured as described above, the same effects as those of the blood pressure measuring device 1 of the above-described first embodiment are achieved. That is, the blood pressure measuring device 1A includes: a second on-off valve 21A (first valve 21A) that is opened and closed under the control of the control unit 55; and a flow restrictor 22 that allows less air to be injected into the sensing cuff 73 than into the pressing cuff 71. Therefore, when air is supplied to the pressing cuff 71 and the sensing cuff 73 by the pump 14, a pressure difference is generated between the pressing cuff 71 and the sensing cuff 73. And when the pressure of the sensing cuff 73 reaches a specified pressure, the control unit 55 closes the second on-off valve 21A, so that a specified injection amount of air can be injected into the sensing cuff 73. Therefore, in blood pressure measurement, the process of the air injection process performed by the measurement processing unit 55a of the control unit 55 only needs to be the control of the second on-off valve 21A, and the measurement time is shortened. Therefore, artificial influences such as body movement are eliminated, and the robustness in actual use is improved in the blood pressure measuring device 1A.

[0135] In addition, in the air injection process during blood pressure measurement, the determination to close the second on-off valve 21A is made based on the air pressure of the sensing cuff 73 detected by the pressure sensor 17. In addition, the pressure of the sensing cuff 73 when the second on-off valve 21A is closed can be set in the same manner as the opening pressure of the first valve 21 of the above-described first embodiment by the appropriate pressure difference between the pressing cuff 71 and the sensing cuff 73 during blood pressure measurement and the resistance value of the flow restrictor 22. That is, it is only necessary to set the pressure of the sensing cuff 73 when the pressure difference between the sensing cuff 73 and the pressing cuff 71 is an appropriate pressure difference during blood pressure measurement as the threshold value for determining to close the second on-off valve 21A, where the pressure difference between the sensing cuff 73 and the pressing cuff 71 is the pressure difference obtained by setting the air injection amount by the flow restrictor 22. In addition, the threshold value is obtained in advance and stored in the storage unit 54.

[0136] Therefore, when the pressure of the sensing cuff 73 reaches the threshold value during blood pressure measurement, the measurement processing unit 55a only needs to perform the control to close the second on-off valve 21A, and it is easy to perform the control of the second on-off valve 21A by the control unit 55. Therefore, the blood pressure measuring device 1A can simplify the control during blood pressure measurement and can reduce power consumption. In addition, only one second on-off valve 21A is required for the electrically controlled valve for injecting air during blood pressure measurement, and the components to be arranged in the device main body 2A can be reduced. Therefore, the device main body 2A can be miniaturized.

[0137] In addition, the blood pressure measuring device 1A sets the second valve 23, which is opened when the pressure of the pressing cuff 71 is lower than the pressure of the sensing cuff 73, in parallel with the flow path passing through the first valve 21 and the baffle 22. Therefore, the air in the sensing cuff 73 passes not only through the flow path passing through the baffle 22 and the first valve 21, but also through the bypass path passing through the second valve 23, and is discharged to the atmosphere through the pressing cuff 71. Therefore, even if the structure of setting the baffle 22 is adopted, the exhaust speed of the sensing cuff 73 can be prevented from decreasing. In addition, the pressing cuff 71 that presses the biological body 200 more is preferentially exhausted rapidly, and when the pressure of the pressing cuff 71 is lower than that of the sensing cuff 73, the second valve 23 is opened, thereby increasing the exhaust speed of the sensing cuff 73. Therefore, the blood pressure measuring device 1A can reduce the load on the biological body caused by the pressure on the biological body after the blood pressure measurement is completed, and can shorten the exhaust time of the sensing cuff 73.

[0138] As described above, according to the blood pressure measurement device 1A of the second embodiment, the primary side of the pressing cuff 71 is branched and the sensing cuff 73 is provided via the second opening and closing valve 21A and the baffle 22. Therefore, the blood pressure measurement device 1A can control the amount of air injected into the sensing cuff 73 to be constant.

[0139] [Third Embodiment]

[0140] Next, use Figure 12 and Figure 13 , the structure of the blood pressure measurement device 1B of the third embodiment is described. It should be noted that the blood pressure measurement device 1B of the third embodiment is an example of applying the blood pressure measurement device 1 of the first embodiment described above to a wearable blood pressure measurement device attached to a wrist 200 as a living body. The same reference numerals are given to the same structures of the blood pressure measurement device 1B of the third embodiment as those of the blood pressure measurement device 1 of the first embodiment described above, and their detailed description is omitted.

[0141] like Figure 12 As shown, the blood pressure measurement device 1B includes: a device body 2 ; a fluid circuit 3 ; a belt 4 that is a fixture for fixing the device body 2 to the wrist; and a collar 5 that is disposed between the belt 4 and the wrist 200 .

[0142] like Figure 12 As shown, the housing 11 of the device body 2 includes: a profile housing 31; and a windshield 32 covering the opening of the profile housing 31 on the side opposite to the wrist 200 side (outside). In addition, the housing 11 includes a back cover provided inside the profile housing 31 on the wrist 200 side.

[0143] The outer shell 31 is formed in a cylindrical shape. The outer shell 31 includes: a pair of ears 31a, which are respectively provided at symmetrical positions in the circumferential direction of the outer peripheral surface; and spring rods 31b, which are respectively provided between two pairs of ears 31a. The windshield 32 is, for example, a circular glass plate. In addition, a base for supporting each component is provided in the outer shell 31.

[0144] The display device 12 is disposed on the base of the contour housing 31 and directly below the windshield 32 .

[0145] The operating device 13 is configured to input instructions from the user. Figure 12 As shown, the operating device 13 includes: a plurality of buttons 41, which are provided on the housing 11; a sensor, which detects the operation of the buttons 41; and a touch panel 43, which is provided on the display device 12 or the windshield 32. The operating device 13 converts the command into an electrical signal by the user's operation. The sensor and the touch panel 43 are electrically connected to the control substrate 20, and output the electrical signal to the control substrate 20.

[0146] like Figure 12 As shown, the belt 4 includes: a first belt 61, a pair of ears 31a and a spring rod 31b provided on one side; a second belt 62, a pair of ears 31a and a spring rod 31b provided on the other side; and a connector connecting the first belt 61 and the second belt 62. The belt 4 is wrapped around the wrist 200 via the collar 5. It should be noted that in this embodiment, the connector is the buckle 61b provided on the first belt 61.

[0147] The first tape 61 is called a so-called mother tape, and is formed into a tape shape that can be connected to the second tape 62. Figure 12 As shown, the first belt 61 has a belt portion 61a and a buckle 61b. The belt portion 61a is configured in a belt shape. The belt portion 61a is formed of a resin material that can be elastically deformed. In addition, the belt portion 61a has flexibility and has a sheet-shaped embedded member inside to suppress the expansion and contraction of the belt portion 61a in the long dimension direction.

[0148] The belt portion 61a has a spring bar 31b at one end and a buckle 61b at the other end. The spring bar 31b provided at one end of the first belt 61 is disposed between the pair of ears 31a, whereby the first belt 61 is rotatably held by the outer shell 31.

[0149] The second belt 62 is called a hook belt and is formed in a belt shape. The second belt 62 is formed of a resin material that can be elastically deformed. In addition, the second belt 62 has flexibility, and has a sheet-like embedded member inside that suppresses the expansion and contraction of the second belt 62 in the longitudinal direction.

[0150] The second band 62 is fixed to the buckle 61b. A spring rod 31b is provided at one end of the second band 62. The spring rod 31b provided at one end of the second band 62 is disposed between a pair of ears 31a, whereby the second band 62 is rotatably held by the contour housing 31.

[0151] In such a band 4, the first band 61 and the second band 62 are integrally connected by the buckle 61b and together with the contour housing 31 form a ring following the circumference of the wrist 200. The band 4 presses the snap ring 5 by forming a ring following the circumference of the wrist, causing the snap ring 5 to elastically deform in a manner following the circumference of the wrist of the wearer of the blood pressure measuring device 1B.

[0152] As Figure 12 shown, the snap ring 5 is configured as a band bent following the circumference of the wrist 200. The snap ring 5 is formed such that one end is separated from the other end. In the snap ring 5, for example, the outer surface on one end side is fixed to the back cover side of the device main body 2 or integrally formed with the back cover and the base of the device main body 2. In the snap ring 5, for example, one end and the other end are disposed at positions protruding more laterally toward the wrist 200 than the device main body 2. Thus, when the blood pressure measuring device 1B is attached to the wrist 200, one end and the other end of the snap ring 5 are disposed on the side of the wrist 200. Further, one end and the other end of the snap ring 5 are adjacent to each other with a prescribed distance therebetween. The snap ring 5 is formed of a resin material, for example.

[0153] Such a snap ring 5 is fixed to the contour housing 31 with one end and the other end facing the second band 62 of the band 4. Further, in the snap ring 5, at least the position facing the palm side of the wrist 200 is bent along the palm side of the wrist 200 in the circumferential direction, thereby holding the cuff structure 6 in a state where it is bent following the shape of the palm side of the wrist 200.

[0154] Further, the snap ring 5 has a hardness with flexibility and shape retention. Here, flexibility means that when an external force of the band 4 is applied to the snap ring 5, the shape deforms radially. For example, flexibility means that when the snap ring 5 is pressed by the band 4, the shape in side view deforms in a manner approaching, following, or imitating the shape of the wrist. Further, shape retention means that the snap ring 5 can maintain the pre-shaped shape without the application of an external force. For example, in the present embodiment, shape retention means that the shape of the snap ring 5 can maintain the shape bent along the circumference of the wrist. The cuff structure 6 is disposed on the inner circumferential surface of the snap ring 5.

[0155] For example, in the fluid circuit 3, the cuff structure 6, the tube group 7, and the fluid control unit 9 are integrally formed. For example, the fluid circuit 3 is constituted by integrally embedding the tube group 7 and the fluid control unit 9 in a part of the cuff structure 6.

[0156] As a specific example, such as Figure 12 and Figure 13 shown, the cuff structure 6 includes a pressing cuff 71, a sensing cuff 73, and a fluid control unit 9. It should be noted that Figure 13 is an exploded view showing the configuration of the snap ring 5 and the cuff structure 6. The cuff structure 6 is laminated and fixed to the inner peripheral surface on the palm side of the wrist of the snap ring 5 in the order of the pressing cuff 71 and the sensing cuff 73 from the inner peripheral surface of the snap ring 5 toward the wrist side.

[0157] It should be noted that the cuff structure 6 has, for example, a back plate 72 that supports the sensing cuff 73 between the pressing cuff 71 and the sensing cuff 73. As a specific example, the back plate 72 is formed to cover the length of the palm side of the wrist 200. The back plate 72 transmits the pressing force from the pressing cuff 71 to the main surface on the side of the back plate 72 of the sensing cuff 73 in a state along the shape of the wrist.

[0158] The pressing cuff 71 is set to have a length substantially the same as the length in the long dimension direction of the snap ring 5, for example. The pressing cuff 71 includes multiple layers, for example, two air bags 81 and a connecting portion 84 provided on one end side in the long dimension direction. The pressing cuff 71 is provided with the fluid control unit 9 on the other end side in the long dimension direction.

[0159] Here, the air bag 81 is a bag-shaped structure. A plurality of air bags 81 are laminated and fluidly connected in the lamination direction. The air bag 81 is formed in a rectangular bag shape that is long in one direction. In addition, the width in the short dimension direction of the air bag 81 is set to be the same as or slightly smaller than the width in the short dimension direction of the snap ring 5. The air bag 81 is formed, for example, by combining two sheet members and thermally welding the two sheet members into a rectangular frame shape that is long in one direction. In addition, the two-layer air bag 81 is formed by thermally welding and combining two air bags 81 into one body or by thermally welding the opposing sheet members of adjacent air bags 81 and then forming the air bag 81 by welding.

[0160] The connecting portion 84 is, for example, a pipe joint. The connecting portion 84 protrudes from the air bag 81. The connecting portion 84 is the first pipe 7a connected to the flow path portion 15.

[0161] The sensing cuff 73 is set to have a length that can be disposed in the area of the wrist where the artery exists, for example. When the blood pressure measuring device 1B is attached to the wrist, the sensing cuff 73 faces the area of the wrist where the artery exists. Here, the artery is the radial artery and / or the ulnar artery. The sensing cuff 73 compresses the area of the palm side of the wrist where the artery exists by expanding. The sensing cuff 73 is pressed toward the wrist side by the expanded pressing cuff 71.

[0162] As a specific example, the sensing cuff 73 includes an airbag 91, a flow path body 92 communicating with the airbag 91, and a connection portion 93 provided at the top end of the flow path body 92. Such a sensing cuff 73 is formed by welding two sheet members together as one body.

[0163] The airbag 91 is configured as a rectangle long in one direction. The airbag 91 is set, for example, to a length that can be disposed in the area of the wrist where the artery exists. The airbag 91 is formed, for example, by combining two sheet members long in one direction and thermally welding the two sheet members into a rectangular frame shape long in one direction.

[0164] The flow path body 92 is integrally provided at a part of one edge portion in the long dimension direction of the airbag 91. As a specific example, the flow path body 92 is provided at the end of the airbag 91 close to the device main body 2. In addition, the flow path body 92 is formed, for example, in a shape long in one direction with a width smaller than the width in the short dimension direction of the airbag 91, and the top end is formed in a circular shape. The flow path body 92 has a connection portion 93 at the top end.

[0165] The flow path body 92 is formed by thermally welding two sheet members into a frame shape long in one direction with the connection portion 93 disposed between the two sheet members. It should be noted that the airbag 91 is configured such that a part of the welding portion that welds the two sheet members into a rectangular frame shape is not welded and this part is continuous with the welding portion forming the flow path body 92, whereby the airbag 91 and the flow path body 92 are fluidly continuous.

[0166] The connection portion 93 is, for example, a pipe joint. The connection portion 93 is provided at the top end of the flow path body 92. In addition, the top end of the connection portion 93 protrudes outward from the sheet member on the side facing the snap ring 5 among the two sheet members constituting the flow path body 92. The connection portion 93 is connected to the flow path portion 15.

[0167] Such a flow path body 92 and connection portion 93 constitute a fifth tube 7e that is connected to the flow path portion 15 via the connection portion 93 and connects the airbag 91 and the pressure sensor 17.

[0168] In the cuff structure 6 configured as described above, the pressing cuff 71 includes the first tube 7a of the tube group 7, and the sensing cuff 73 includes the fifth tube 7e.

[0169] The fluid control portion 9 is disposed, for example, on the inner surface of the snap ring 5 and at the end portion on the palm side of the wrist. The fluid control portion 9 is integrally formed with the end portions of the pressing cuff 71 and the sensing cuff 73. As a specific example, the fluid control portion 9 is integrally formed with the end portion of the pressing cuff 71, and a part of it is fluidly connected to the sensing cuff 73.

[0170] For example, the fluid control unit 9 includes a second tube 7b, a third tube 7c, a fourth tube 7d, a first valve 21, a flow restrictor 22, and a second valve 23. In the fluid control unit 9, the second tube 7b, the third tube 7c, the fourth tube 7d, the first valve 21, the flow restrictor 22, and the second valve 23 are integrally formed.

[0171] The second tube 7b, the third tube 7c, and the fourth tube 7d are formed, for example, by a part of a pair of sheet members of an airbag 81 that constitutes one side of the pressure cuff 71. For example, when welding the pair of sheet members, the second tube 7b, the third tube 7c, and the fourth tube 7d are formed in the gap between the pair of sheet members by not welding the regions that constitute the second tube 7b, the third tube 7c, and the fourth tube 7d. The first valve 21, the flow restrictor 22, and the second valve 23 are disposed in the gap between the pair of sheet members that constitute the second tube 7b, the third tube 7c, and the fourth tube 7d. In addition, the secondary side of the confluence portion 7d1 of the fourth tube 7d is connected to the sensing cuff 73.

[0172] The blood pressure measuring device 1B configured as such has the same effects as the blood pressure measuring device 1 of the above-described first embodiment. Moreover, the blood pressure measuring device 1B integrally forms the second tube 7b, the third tube 7c, the fourth tube 7d, the first valve 21, the flow restrictor 22, and the second valve 23 to form the fluid control unit 9, and integrally connects the fluid control unit 9 to the ends of the pressure cuff 71 and the sensing cuff 73. In addition, the fluid control unit 9 is configured to be disposed at the end of the snap ring 5. Such a blood pressure measuring device 1B is configured to be able to integrally arrange the fluid control unit 9, the pressure cuff 71, and the sensing cuff 73 on the snap ring 5. Therefore, it is not necessary to dispose the fluid control unit 9 in the device main body 2, and the device main body 2 can be miniaturized. Moreover, since the fluid control unit 9 is disposed at the end of the snap ring 5, the fluid control unit 9 can be prevented from obstructing blood pressure measurement during blood pressure measurement.

[0173] [Other Embodiments]

[0174] It should be noted that the present invention is not limited to the above-described embodiments. For example, in the above example, an example in which the fluid circuits 3 and 3A are disposed outside the device main body 2 in the blood pressure measuring devices 1, 1A, and 1B of each embodiment is described, but it is not limited thereto. For example, the blood pressure measuring devices 1 and 1A may also adopt a configuration in which a part of the fluid circuits 3 and 3A is accommodated in the device main body 2. As a specific example, it may be as Figure 14 shown in the blood pressure measuring device 1C of the fourth embodiment, for example, a configuration in which the first valve 21, the flow restrictor 22, and the second valve 23 that constitute the fluid control unit 9 in the configuration of the fluid circuit 3 and a part of the tube group 7 for fluidly connecting them to other components are accommodated in the device main body 2. For example, in this example, the second tube 7b, the third tube 7c, and the fourth tube 7d are accommodated in the device main body 2.

[0175] Similarly, as a specific example, it can also be like Figure 15 the blood pressure measurement device 1D of the fifth embodiment shown, for example, adopting a configuration in which the first valve 21A, the flow restrictor 22, the second valve 23 that constitute the fluid control unit 9A in the configuration of the fluid circuit 3A, and a part of the pipe group 7 for connecting them to other constituent fluids are accommodated in the device main body 2. In this example, for instance, the second pipe 7b and the fourth pipe 7d are accommodated in the device main body 2.

[0176] In addition, in the above example, as an example of applying the blood pressure measurement device 1 of the first embodiment to a wearable blood pressure measurement device attached to the wrist 200, the blood pressure measurement device 1B of the third embodiment has been described, but it is not limited thereto. For example, the blood pressure measurement device 1A of the second embodiment can also be applied to a wearable blood pressure measurement device equivalent to the wearable blood pressure measurement device 1B of the third embodiment. In such a case, it is only necessary to accommodate the second on-off valve 21A (the first valve 21A) in the housing 11 and integrally form the flow restrictor 22, the second valve 23, and the respective pipes 7b, 7d in the fluid control unit 9A at the respective ends of the pressure cuff 71 and the sensing cuff 73.

[0177] In addition, the blood pressure measurement devices 1, 1A can also be configured to be attached to the upper arm. In the case of adopting such a configuration, the blood pressure measurement devices 1, 1A only need to set the first cuff 71 as a winding cuff wound around the upper arm and the second cuff 73 as a measurement cuff 73. For example, an example of the blood pressure measurement device 1E attached to the upper arm of the sixth embodiment is shown in Figure 16 . It should be noted that in the blood pressure measurement device 1E attached to the upper arm, it is also only necessary to set the first cuff 71 as a winding cuff. In addition, in the case of adopting such a blood pressure measurement device 1, 1A attached to the upper arm, a configuration with an automatic winding function can also be adopted.

[0178] In addition, regarding the above-mentioned blood pressure measurement devices 1, 1A, 1B, as an example of blood pressure measurement, the decompression measurement method has been exemplified and described, but it is not limited thereto. As an example of blood pressure measurement, the blood pressure measurement devices 1, 1A, 1B can also adopt the pressurization measurement method. In the case of the blood pressure measurement devices 1, 1A, 1B adopting such a pressurization measurement method, as the blood pressure measurement device of the seventh embodiment, it is only necessary to set the on-off valve 16 as a rapid exhaust valve capable of rapid exhaust and perform blood pressure measurement by the pressurization measurement method.

[0179] In addition, in the above example, the configuration of the blood pressure measurement devices 1, 1A, and 1B having two cuffs 71 and 73 has been described, but it is not limited thereto. That is, the blood pressure measurement devices 1 and 1A may also adopt a configuration having three or more cuffs and fluid control units 9 and 9A are respectively provided between two cuffs. For example, as Figure 17 illustrated by way of example, in the case of adopting three cuffs, it is possible to provide not only a pressing cuff 71 and a sensing cuff 73 but also a stretching cuff 74 provided on the dorsal side of the wrist and stretching the side of the hand of the wrist by inflation, an auxiliary cuff for pressing the dorsal side of the wrist, etc. as the third cuff 74. In addition, the number of cuffs may be four or more. And, it is only necessary to adopt a configuration in which fluid control units 9 and 9A are respectively provided between the stretching cuff 74 and the pressing cuff 71 and between the pressing cuff 71 and the sensing cuff 73. The pressures (pressure differences) for opening and closing the valves of the plurality of fluid control units 9 and 9A and the resistance values of the flow restrictors are appropriately set so that the injection amounts of the secondary-side cuffs are constant. In Figure 17 , as an example of the blood pressure measurement device 1F of the eighth embodiment, an example in which two fluid control units 9 and 9A are provided in the fluid circuit 3F is shown. It should be noted that in Figure 17 , the first valve (first one-way valve) 21 of the secondary-side fluid control unit 9A is denoted as the third one-way valve 21, the flow restrictor 22 is denoted as the second flow restrictor 22, and the second valve (second one-way valve) 23 is denoted as the fourth one-way valve 23.

[0180] In addition, when the blood pressure measurement devices 1, 1A, and 1B are configured to have three or more cuffs, it is also possible to adopt a configuration in which a fluid control unit 9, 9A (first fluid control unit) for controlling the injection amount is provided between two cuffs and a second fluid control unit 9G for controlling the pressure ratio is provided between the other two cuffs. Next, Figure 18 is used to describe the blood pressure measurement device 1G of the ninth embodiment. It should be noted that the same reference numerals are given to the configurations equivalent to those of the blood pressure measurement devices of the above-described respective embodiments in the configuration of the blood pressure measurement device 1G, and the detailed description thereof is omitted.

[0181] The blood pressure measurement device 1G includes a device main body 2 and a fluid circuit 3G. The fluid circuit 3G includes a cuff structure 6, a tube group 7, a first fluid control unit 9, and a second fluid control unit 9G. It should be noted that the first fluid control unit 9 may also be the above-mentioned fluid control unit 9A. The cuff structure 6 includes a pressure cuff 71 as the first cuff 71, a sensing cuff 73 as the second cuff 73, and a stretching cuff 74 as the third cuff 74. For example, the stretching cuff 74 has more air bags than the pressure cuff 71 and expands more than the pressure cuff 71. That is, the stretching cuff 74 is set to have a larger volume when expanded than the pressure cuff 71 and the sensing cuff 73. In addition, for example, the stretching cuff 74 is provided at a position closer to the primary side (pump 14 side) than the pressure cuff 71. It should be noted that in the case of having multiple cuffs, for example, the cuff with a larger volume when expanded is arranged on the pump 14 side of the fluid circuit.

[0182] As Figure 18 shown, the first fluid control unit 9 is provided, for example, between the stretching cuff 74 and the pressure cuff 71.

[0183] The second fluid control unit 9G controls the pressure ratio of the air in the two cuffs to be constant by the fluid resistance ratio of the two flow restrictors 24 and 25. As Figure 18 shown, the second fluid control unit 9G is provided, for example, between the pressure cuff 71 and the sensing cuff 73.

[0184] As a specific example, the second fluid control unit 9G includes a primary side flow restrictor 24, a secondary side flow restrictor 25, and a third valve 26.

[0185] The primary side flow restrictor 24 becomes the resistance of the fluid passing through, and becomes the resistance of air in this embodiment. The primary side flow restrictor 24 has, for example, a flow path cross-sectional area smaller than the flow path cross-sectional areas of the primary side and the secondary side of the primary side flow restrictor 24, that is, smaller than the flow path cross-sectional areas of the second tube 7b and the third tube 7c. The primary side flow restrictor 24 is, for example, a throttling member. The primary side flow restrictor 24 reduces the flow path in the flow path from the pressure cuff 71 to the sensing cuff 73 so that the flow rate of the air supplied to the secondary side of the primary side flow restrictor 24 is less than the flow rate of the air supplied to the pressure cuff 71.

[0186] The secondary flow restrictor 25 creates resistance to the fluid passing through it, which becomes resistance to air in this embodiment. The secondary flow restrictor 25, for example, has a flow path cross-sectional area smaller than the flow path cross-sectional areas of the primary side and the secondary side of the secondary flow restrictor 25, that is, smaller than the flow path cross-sectional areas of the second tube 7b and the third tube 7c. The secondary flow restrictor 25 is, for example, a throttling element. The secondary flow restrictor 25 reduces the flow path in the flow path from between the primary flow restrictor 24 and the secondary flow restrictor 25 to the atmosphere, so that the flow rate of the air supplied to the secondary side (atmosphere) of the secondary flow restrictor 25 is less than the flow rate of the air supplied to the primary flow restrictor 24 and the secondary flow restrictor 25. That is, when a part of the air supplied to the flow path between the primary flow restrictor 24 and the secondary flow restrictor 25 flows to the sensing cuff 73 and the atmosphere, the secondary flow restrictor 25 becomes the resistance to the flow of air to the atmosphere side, controlling the flow rate of the air injected into the sensing cuff 73 and the flow rate of the air flowing out to the atmosphere.

[0187] Regarding such a fluid resistance ratio between the primary flow restrictor 24 and the secondary flow restrictor 25, for example, the relationship between the fluid resistance ratio of the primary flow restrictor 24 and the secondary flow restrictor 25 and the measurement error is obtained through experiments to set the optimal fluid resistance ratio. When listing specific examples, different fluid resistance ratios are set for the fluid resistance ratio between the primary flow restrictor 24 and the secondary flow restrictor 25, blood pressure is measured multiple times, the respective blood pressure errors are obtained, and the optimal fluid resistance ratio is deduced based on this blood pressure measurement error. For example, assuming that the blood pressure error is approximately 5 mmHg when the first fluid resistance ratio (primary flow restrictor 24 / secondary flow restrictor 25) is 0.67, and the blood pressure error is approximately -15 mmHg when the second fluid resistance ratio is 1. Based on this relationship, it can be deduced that the optimal fluid resistance ratio when the blood pressure error becomes 0 mmHg is 0.75. Then, the primary flow restrictor 24 and the secondary flow restrictor 25 with such a fluid resistance ratio are set. It should be noted that such a relationship of the fluid resistance ratio between the primary flow restrictor 24 and the secondary flow restrictor 25 changes according to the different pressing forces of the cuffs 71 and 73 of the blood pressure measuring device 1G, so it is adjusted according to the characteristics of the cuffs 71 and 73.

[0188] The third valve 26 opens when the pressure on the primary side is lower than the pressure on the secondary side. Specifically, the third valve 26 closes when the pressure on the cuff 71 pressing side is equal to or higher than the pressure on the flow path (sensing cuff 73) side between the primary flow restrictor 24 and the secondary flow restrictor 25, and opens when the pressure on the cuff 71 pressing side is lower than the pressure on the flow path side (sensing cuff 73 side) between the primary flow restrictor 24 and the secondary flow restrictor 25. Such a third valve 26, for example, is always closed during blood pressure measurement, and opens when the pressure difference between the pressure of the pressing cuff 71 and the pressure of the sensing cuff 73 disappears during exhaust and reaches the opening pressure where the pressure of the pressing cuff 71 is lower than the pressure of the sensing cuff 73. The third valve 26 is, for example, a one-way valve.

[0189] For example, the opening pressure of the third valve 26 is set to a pressure suitable for exhausting the compression cuff 71 and the sensing cuff 73, for example. As a specific example, the opening pressure of the third valve 26 is set to 0 mmHg so that the third valve 26 opens when the pressure of the compression cuff 71 is lower than the pressure of the sensing cuff 73.

[0190] It should be noted that the third valve 26 is configured to open when the pressure on the primary side is lower than the pressure on the secondary side, so as to prevent the air in the compression cuff 71 from flowing to the sensing cuff 73 side during exhaust. However, as long as the air does not substantially flow from the compression cuff 71 to the sensing cuff 73 during the exhaust of the fluid circuit 3G, the third valve 26 can also be set to an opening pressure that opens when the pressure on the primary side is slightly higher than the pressure on the secondary side.

[0191] The fluid circuit 3G having such a first fluid control unit 9 and a second fluid control unit 9G is connected as follows through the tube group 7. That is, the compression cuff 71 is provided on the secondary side of the first flow restrictor 22 and the second valve 23. In addition, a primary side flow restrictor 24 and a secondary side flow restrictor 25 are provided on the secondary side of the compression cuff 71, and the sensing cuff 73 is connected to the flow path between the primary side flow restrictor 24 and the secondary side flow restrictor 25. In addition, the third valve 26 is connected in parallel to the primary side flow restrictor 24 on the secondary side of the compression cuff 71.

[0192] In such a fluid circuit 3G, when the on-off valve 16 is closed and the pump 14 is started to be driven by the measurement processing unit 55a of the control unit 55 during blood pressure measurement, first, air is supplied to the stretching cuff 74. At this time, the first valve 21 opens. In addition, since the air is first supplied to the stretching cuff 74, the second valve 23 closes. Therefore, the air supplied to the stretching cuff 74 is supplied to the compression cuff 71 side via the first valve 21 and the flow restrictor 22. At this time, since the air supplied to the compression cuff 71 passes through the flow restrictor 22, the amount of air supplied to the compression cuff 71 side is less than the amount of air injected into the stretching cuff 74 side. Therefore, the pressure increases of the stretching cuff 74 and the compression cuff 71 are also different, and the stretching cuff 74 and the compression cuff 71 are pressurized in such a way that the pressure of the stretching cuff 74 is maintained higher than the pressure of the compression cuff 71.

[0193] In addition, at the same time, since the air passing through the first flow restrictor 22 from the stretch cuff 74 causes the pressure on the primary side of the third valve 26 to be higher than the pressure on the secondary side, the third valve 26 closes. Then, a part of the air passing through the first flow restrictor 22 from the stretch cuff 74 and supplied to the pressure cuff 71 side is supplied to the pressure cuff 71, and the remaining air passes through the primary side flow restrictor 24 and is supplied to the flow path between the primary side flow restrictor 24 and the secondary side flow restrictor 25. At this time, due to the resistance of the primary side flow restrictor 24, the injection amount of the air supplied to the pressure cuff 71 is larger than the injection amount of the air supplied to the flow path between the primary side flow restrictor 24 and the secondary side flow restrictor 25.

[0194] In addition, a part of the air supplied to the flow path between the primary side flow restrictor 24 and the secondary side flow restrictor 25 is injected into the sensing cuff 73, and the remaining air supplied to the flow path between the primary side flow restrictor 24 and the secondary side flow restrictor 25 passes through the secondary side flow restrictor 25 and is discharged to the atmosphere. At this time, depending on the resistance of the secondary side flow restrictor 25, the flow rates of the air in the air supplied to the flow path between the primary side flow restrictor 24 and the secondary side flow restrictor 25 that flow into the sensing cuff 73 and the atmosphere respectively change.

[0195] In addition, the fluid resistances of the primary side flow restrictor 24 and the secondary side flow restrictor 25 have been set, so the pressure ratio between the pressure of the pressure cuff 71 and the pressure of the sensing cuff 73 is constant from the start of the air supply by the pump 14 until the air supply stops.

[0196] Then, when the pressure difference between the stretch cuff 74 and the pressure cuff 71 reaches the opening pressure of the first valve 21, for example, the first valve 21 closes. After the first valve 21 closes, the air supplied by the pump 14 is only supplied to the stretch cuff 74.

[0197] It should be noted that when discharging the air supplied to the fluid circuit 3G, in the fluid circuit 3G, when the pressure of the stretch cuff 74 on the pump 14 side (primary side) drops to a specified pressure, the second valve 23 and the third valve 26 provided in the bypass for exhaust open. Therefore, the pressure cuff 71 and the sensing cuff 73 are connected to the atmosphere via the on-off valve 16.

[0198] According to the blood pressure measuring device 1G of the ninth embodiment configured as described above, through the first fluid control unit 9, the injection amount of the secondary side cuff 71 in the two cuffs 74 and 71 is constant, and through the second fluid control unit 9G, the pressure ratio of the other two cuffs 71 and 73 is constant.

[0199] Note that in this embodiment, as the fluid circuit 3G, a configuration in which the first fluid control unit 9 is provided between the stretching cuff 74 and the pressing cuff 71 and the second fluid control unit 9G is provided between the pressing cuff 71 and the sensing cuff 73 has been described, but it is not limited thereto. For example, it is also possible to adopt a configuration in which the first fluid control unit 9G is provided between the stretching cuff 74 and the pressing cuff 71 and the second fluid control unit 9 is provided between the pressing cuff 71 and the sensing cuff 73, as in the fluid circuit 3H of the blood pressure measuring device 1H of the tenth embodiment shown in Figure 19 . In addition, the blood pressure measuring device 1H may also use the second fluid control unit as the fluid control unit 9A.

[0200] In addition, the present invention is not limited to the above-described embodiments. For example, in the cuff structure 6, a plurality of cuffs can be appropriately set, and they can also be cuffs other than the above-described pressing cuff, sensing cuff, stretching cuff, winding cuff, and measuring cuff.

[0201] In addition, in the above example, each component of the fluid circuit 3 is defined by components that are not electrically controlled and are provided outside the device main body 2, but it is not limited thereto. That is, the fluid circuit 3 may also adopt a configuration that includes not only the cuff structure 6, the tube group 7, and the fluid control units 9, 9A, 9G but also the pump 14, the on-off valve 16, and the pressure sensor 17.

[0202] In addition, in view of the miniaturization of the device main body 2, the components of the fluid circuit 3 are preferably provided outside the device main body 2, but of course, they can also be accommodated in the device main body 2.

[0203] That is, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist thereof at the implementation stage. In addition, the embodiments can be combined as appropriately as possible, and in this case, the combined effects can be obtained. Moreover, the above embodiments include inventions at various stages, and various inventions can be extracted by combining the disclosed multiple constituent elements.

[0204] Description of Reference Numerals

[0205] 1: Blood pressure measuring device;

[0206] 1A: Blood pressure measuring device;

[0207] 1B: Blood pressure measuring device;

[0208] 1C: Blood pressure measuring device;

[0209] 1D: Blood pressure measuring device;

[0210] 1E: Blood pressure measuring device;

[0211] 1F: Blood pressure measuring device;

[0212] 1G: Blood pressure measuring device;

[0213] 1H: Blood pressure measuring device;

[0214] 2: Device main body;

[0215] 2A: Device main body;

[0216] 3: Fluid circuit;

[0217] 3A: Fluid circuit;

[0218] 3F: Fluid circuit;

[0219] 3G: Fluid circuit;

[0220] 3H: Fluid circuit;

[0221] 4: Fixing member (strap);

[0222] 5: Snap ring;

[0223] 6: Cuff structure;

[0224] 7: Tube group;

[0225] 7a: First tube;

[0226] 7b: Second tube;

[0227] 7b1: Branch portion;

[0228] 7b2: Tube portion;

[0229] 7b3: Tube portion;

[0230] 7c: Third tube;

[0231] 7d: Fourth tube;

[0232] 7d1: Confluence portion;

[0233] 7d2: Tube portion;

[0234] 7d3: Tube portion;

[0235] 7e: Fifth tube;

[0236] 9: Fluid control section;

[0237] 9A: Fluid control section;

[0238] 9G: Fluid control section;

[0239] 11: Housing;

[0240] 12: Display device;

[0241] 13: Operating device;

[0242] 14: Pump;

[0243] 15: Flow path section;

[0244] 15a: Flow path;

[0245] 15b: Flow path;

[0246] 15c: Flow path;

[0247] 16: On-off valve (first on-off valve);

[0248] 17: Pressure sensor;

[0249] 18: Power supply unit;

[0250] 19: Communication device;

[0251] 20: Control board;

[0252] 21: First valve;

[0253] 21A: First valve (switching valve);

[0254] 22: Flow restrictor;

[0255] 23: Second valve;

[0256] 24: Primary side flow restrictor;

[0257] 25: Secondary side flow restrictor;

[0258] 26: Third valve;

[0259] 31: Contour housing;

[0260] 31a: Ear;

[0261] 31b: Spring rod;

[0262] 32: Windshield;

[0263] 41: Button;

[0264] 43: Touch panel;

[0265] 51: Substrate;

[0266] 54: Storage unit;

[0267] 55: Control unit;

[0268] 55a: Measurement processing unit;

[0269] 61: First belt;

[0270] 61a: Belt section;

[0271] 61b: buckle;

[0272] 62: second belt;

[0273] 71: first cuff;

[0274] 72: back plate;

[0275] 73: second cuff;

[0276] 74: third cuff;

[0277] 81: air bag;

[0278] 84: connecting part;

[0279] 91: air bag;

[0280] 92: flow path body;

[0281] 93: connecting part;

[0282] 200: organism (wrist);

[0283] 210: artery.

Claims

1. A fluid circuit, the fluid circuit comprising: A first cuff connected to the secondary side of a pump that supplies fluid to the secondary side; A second cuff connected to the secondary side of the first cuff; A first valve provided between the first cuff and the second cuff, closing when the pressure difference between the first cuff and the second cuff becomes a specified pressure difference; And A flow restrictor provided between the first valve and the second cuff, The first cuff presses the second cuff against the living body by expanding.

2. The fluid circuit according to claim 1, Wherein, The fluid circuit comprises: A second valve provided in parallel with the first valve and the flow restrictor, opening when the pressure of the first cuff is lower than the pressure of the second cuff.

3. A blood pressure measurement device, the blood pressure measurement device comprising: A pump that supplies fluid to the secondary side; The fluid circuit according to claim 1 or 2; An on-off valve provided between the pump and the first cuff, opening and closing the flow path to the atmosphere; A pressure sensor connected to the second cuff; and A control unit that controls the pump and the on-off valve based on the pressure detected by the pressure sensor.

4. The blood pressure measurement device according to claim 3, Wherein, The blood pressure measurement device comprises: A device main body that houses the pump, the on-off valve, the pressure sensor, and the control unit, and the first valve and the flow restrictor are integrated with the first cuff.

5. A fluid circuit, the fluid circuit comprising: A first cuff connected to the secondary side of a pump that supplies fluid to the secondary side; A second cuff branched between the pump and the first cuff; A switching valve branched between the pump and the first cuff, provided on the primary side of the second cuff, closing when the pressure difference between the first cuff and the second cuff becomes a specified pressure difference; and A flow restrictor provided between the switching valve and the second cuff, The first cuff presses the second cuff against the living body by expanding.

6. The fluid circuit according to claim 5, Wherein, The fluid circuit comprises: A second valve provided in parallel with the flow restrictor, opening when the pressure of the first cuff is lower than the pressure of the second cuff.

7. A blood pressure measurement device, the blood pressure measurement device comprising: A pump that supplies fluid to the secondary side; The fluid circuit according to claim 5 or 6; An on-off valve provided between the pump and the first cuff and the switching valve, opening and closing the flow path to the atmosphere; A pressure sensor connected to the second cuff; and A control unit that controls the pump, the switching valve, and the on-off valve based on the pressure detected by the pressure sensor.

8. The blood pressure measurement device according to claim 7, Wherein, The blood pressure measurement device comprises: A device main body that houses the pump, the switching valve, the on-off valve, the pressure sensor, and the control unit, The flow restrictor is integrated with the first cuff.

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