Sphygmomanometer

Abstract

According to the non-invasive sphygmomanometer, the blood pressure can be measured when the cuff is pressurized, and the service life of the pressurizing pump can be prolonged; a non-invasive sphygmomanometer (1) for measuring blood pressure is provided with: a cuff (3) wound around a site (2) to be measured; a pressure pump (7) for supplying air to the cuff (3); and an air tank (8) and air filters (10, 11) disposed in a supply path for air from the pressure pump (7) to the cuff (3). An air chamber (23) is formed inside the air tank (8), the air chamber (23) is disposed closer to the pressure pump (7) than all the air filters (10, 11) in the air supply path from the pressure pump (7) to the cuff (3), and air flowing into the air tank (8) from the pressure pump (7) flows into the air chamber (23).

Description

Technical Field

[0001] This invention relates to a non-invasive blood pressure monitor. Background Technology

[0002] Currently, non-invasive electronic blood pressure monitors with a cuff and a pressure pump for supplying air to the cuff are known (for example, see Patent Document 1). The electronic blood pressure monitor described in Patent Document 1 includes an airflow control unit disposed between the cuff and the pressure pump. The airflow control unit includes an air reservoir and microtubes disposed on both sides of the air reservoir. The airflow inlet of the air reservoir is connected to the pressure pump via the microtubes and a tubing, and the airflow outlet of the air reservoir is connected to the cuff via the microtubes and a tubing. In the electronic blood pressure monitor described in Patent Document 1, under the action of the airflow control unit, changes in the flow rate of the pressure pump do not manifest as changes in cuff pressure, and pressure vibrations caused by the pulsation of the pressure pump do not propagate to the cuff pressure. Therefore, in this electronic blood pressure monitor, blood pressure can be measured while the cuff is being pressurized.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 62-192139 Summary of the Invention

[0006] In the electronic blood pressure monitor described in Patent Document 1, as mentioned above, blood pressure can be measured while the cuff is being inflated. However, in this electronic blood pressure monitor, the micro-tube disposed between the air inlet of the gas reservoir and the pressurizing pump easily places a large load on the pressurizing pump when the cuff is inflated. Therefore, there is a concern that the lifespan of the pressurizing pump may be shortened in this electronic blood pressure monitor. In addition, in the electronic blood pressure monitor described in Patent Document 1, the inflatation rate of the cuff cannot be controlled.

[0007] Therefore, the first technical objective of this invention is to provide a non-invasive blood pressure monitor that can measure blood pressure while the cuff is being inflated and that can extend the lifespan of the inflation pump. Furthermore, the second technical objective of this invention is to provide a non-invasive blood pressure monitor that allows control of the cuff inflation rate.

[0008] To solve the aforementioned first technical problem, the blood pressure monitor of the present invention is a non-invasive blood pressure monitor for measuring blood pressure, characterized in that it comprises: a cuff wrapped around the area to be measured; a pressure pump for supplying air to the cuff; and an air canister and an air filter disposed in the air supply path from the pressure pump toward the cuff, wherein an air chamber is formed inside the air canister, and the air chamber is disposed in the air supply path from the pressure pump toward the cuff at a position closer to the pressure pump side than all the air filters, and air flowing from the pressure pump into the air canister flows into the air chamber.

[0009] In the blood pressure monitor of the present invention, an air canister and an air filter are arranged in the air supply path from the pressurizing pump to the cuff. Therefore, in the present invention, changes in the flow rate of air supplied from the pressurizing pump to the cuff are less likely to manifest as changes in the pressure inside the cuff. Therefore, in the present invention, blood pressure can be measured while the cuff is pressurized. Furthermore, in the present invention, air flowing from the pressurizing pump into the air canister flows into the air chamber without passing through the air filter, and this air chamber is positioned closer to the pressurizing pump than all the air filters in the air supply path from the pressurizing pump to the cuff. Therefore, in the present invention, the pressurizing pump is less likely to be subjected to a large load when the cuff is pressurized via the air canister. Therefore, in the present invention, blood pressure can be measured while the cuff is pressurized, and the lifespan of the pressurizing pump can be extended.

[0010] Furthermore, in order to solve the aforementioned second technical problem, the blood pressure monitor of the present invention is a non-invasive blood pressure monitor for measuring blood pressure, characterized in that it comprises: a cuff wrapped around the area to be measured; a pressure pump for supplying air to the cuff; an air canister and an air filter disposed in the air supply path from the pressure pump toward the cuff; a first pressure sensor for detecting the internal pressure of the air canister; a second pressure sensor for detecting the internal pressure of the cuff; and a blood pressure monitor control unit having a pump control circuit for controlling the pressure pump, wherein an air chamber is formed inside the air canister, and the air chamber is disposed in the air supply path from the pressure pump toward the cuff at a position closer to the pressure pump than at least one air filter, the first pressure sensor detects the air pressure in the air chamber, and the blood pressure monitor control unit controls the pressure pump based on the detection result of the first pressure sensor.

[0011] The blood pressure monitor of the present invention includes a first pressure sensor for detecting the air pressure inside an air chamber disposed in the air supply path from the pressurizing pump to the cuff. The blood pressure monitor control unit controls the pressurizing pump based on the detection result of the first pressure sensor. Therefore, in the present invention, the pressurization rate of the cuff can be controlled. Furthermore, in the present invention, since the first pressure sensor detects the air pressure in an air chamber disposed in the air supply path from the pressurizing pump to the cuff, located closer to the pressurizing pump side than at least one air filter, the detection result of the first pressure sensor is less susceptible to the influence of pulse waves at the measurement site due to the action of the air filter. Therefore, in the present invention, the pressurization rate of the cuff can be controlled with high precision based on the detection result of the first pressure sensor.

[0012] (Invention effect)

[0013] As described above, in the blood pressure monitor of the present invention, blood pressure can be measured while the cuff is being inflated, and the lifespan of the inflation pump can be extended. Furthermore, in the blood pressure monitor of the present invention, the inflation rate of the cuff can be controlled. Attached Figure Description

[0014] Figure 1 This is a simplified diagram illustrating the structure of a blood pressure monitor according to embodiments of the present invention.

[0015] Figure 2 It is used for explanation Figure 1 The diagram shown illustrates the components of a blood pressure monitor.

[0016] Figure 3 This is a simplified diagram illustrating the configuration of a blood pressure monitor according to another embodiment of the present invention.

[0017] Figure 4 It is used for explanation Figure 3 The diagram shown illustrates the components of a blood pressure monitor.

[0018] (Symbol Explanation)

[0019] 1: Blood pressure monitor

[0020] 2: The part being measured

[0021] 3: Sleeves

[0022] 7: Booster Pump

[0023] 8: Gas cylinder

[0024] 10, 11: Air filters

[0025] 12: Barometric pressure sensor (first barometric pressure sensor)

[0026] 13: Barometric pressure sensor (second barometric pressure sensor)

[0027] 17: Blood Pressure Monitor Control Section

[0028] 23: Air chamber

[0029] 24: Air chamber

[0030] 31: Pump control circuit

[0031] 40: Air chamber Detailed Implementation

[0032] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0033] (Components of a blood pressure monitor)

[0034] Figure 1 This is a simplified diagram illustrating the configuration of the blood pressure monitor 1 according to an embodiment of the present invention. Figure 2 It is used for explanation Figure 1 The diagram shown illustrates the structure of the blood pressure monitor 1.

[0035] The blood pressure monitor 1 of this embodiment is a non-invasive blood pressure monitor for measuring the blood pressure of humans or laboratory animals. The blood pressure monitor 1 includes: a cuff 3 that is wrapped around the arm or other part of the body being measured 2 to compress the artery; a Korotkoff microphone 4 (hereinafter referred to as "microphone 4") mounted on the cuff 3; and a blood pressure monitor body 5 connected to the cuff 3. The blood pressure monitor body 5 has a pressure pump 7, an air tank 8, and air filters 10 and 11. The pressure pump 7 supplies air to the cuff 3, and the air tank 8 and air filters 10 and 11 are arranged in the air supply path from the pressure pump 7 to the cuff 3. The blood pressure monitor body 5 of this embodiment includes two air filters 10 and 11.

[0036] In addition, the blood pressure monitor body 5 includes: a pressure sensor 12 for detecting the air pressure inside the gas canister 8; a pressure sensor 13 for detecting the air pressure (internal pressure) inside the cuff 3; an intermediate exhaust valve 14 and a constant-speed exhaust valve 15 for venting air from inside the gas canister 8; a rapid exhaust valve 16 for venting air from inside the cuff 3; and a blood pressure monitor control unit 17 for controlling the blood pressure monitor 1. In this configuration, the pressure sensor 12 is a first pressure sensor, and the pressure sensor 13 is a second pressure sensor.

[0037] The gas tank 8 is, for example, formed as a cylindrical (tubular) shape with both ends closed. The gas tank 8 is, for example, formed of polyvinyl chloride. For example, the overall length of the gas tank 8 is about 150 mm, the outer diameter of the gas tank 8 is about 38 mm, and the wall thickness of the gas tank 8 is about 3.5 mm.

[0038] Air filter 10 consists of two silencers 21 and a silencer mounting plate 22 that fixes the two silencers 21. Similarly, air filter 11 consists of two silencers 21 and a silencer mounting plate 22. Air filters 10 and 11 function as air dampers. Air filters 10 and 11 are disposed inside air tank 8. The silencer mounting plate 22 is formed in the shape of a circular plate and is fixed to the inner circumferential surface of air tank 8. Silencers 21 are fixed to the silencer mounting plate 22 from both sides.

[0039] The interior of the air tank 8 is divided by air filters 10 and 11, forming air chambers 23 and 24, and a connecting chamber 25. In this embodiment, the interior of the air tank 8 is composed of air chambers 23, 24, and 25. Air chamber 23 is formed between one end of the air tank 8 and air filter 10. Air chamber 24 is formed between air filter 10 and air filter 11. Connecting chamber 25 is formed between the other end of the air tank 8 and air filter 11. Connecting chamber 25 is narrower than air chambers 23 and 24.

[0040] Air chamber 23 is connected to pressurizing pump 7 via air pipe 26. Air flowing from pressurizing pump 7 into air tank 8 flows into air chamber 23, with one end of air pipe 26 installed at the air inlet of air tank 8. Connecting chamber 25 is connected to cuff 3 via air pipe 27. Air flowing from air tank 8 flows out through connecting chamber 25, with one end of air pipe 27 connected to the air outlet of air tank 8. The air inlet and outlet are, for example, pipes made of aluminum alloy. Thus, air chamber 23 and air chamber 24 are formed inside air tank 8. In the air supply path from pressurizing pump 7 to cuff 3, air chamber 23 is positioned closer to pressurizing pump 7 than all air filters 10, 11, and air chamber 24 is positioned closer to pressurizing pump 7 than one air filter 11.

[0041] The pressure sensor 12 is connected to the air chamber 24 via an air tube 28, one end of which is installed at the air inlet / outlet of the air canister 8. The air inlet / outlet is, for example, a tube made of aluminum alloy. The pressure sensor 12 functions to detect the air pressure in the air chamber 24. That is, the pressure sensor 12 functions to detect the pressure of the air in the air canister 8 after passing through the air filter 10. The pressure sensor 13 is connected to the cuff 3 and the connecting chamber 25 via an air tube 27, etc. As described above, the pressure sensor 13 functions to detect the internal pressure of the cuff 3. In this embodiment, the detection result of the pressure sensor 13 is used for blood pressure measurement, while the detection result of the pressure sensor 12 is not used for blood pressure measurement.

[0042] Intermediate vent valve 14 and constant-speed vent valve 15 are connected to air chamber 24 via air tube 28. Quick vent valve 16 is connected to cuff 3 and connecting chamber 25 via air tube 27, etc. Intermediate vent valve 14 and quick vent valve 16 are on / off valves. As described later, blood pressure can be measured using the sphygmomanometer 1 when the cuff 3 is depressurized. Intermediate vent valve 14 and constant-speed vent valve 15 are used during blood pressure measurement when the cuff 3 is depressurized. Quick vent valve 16 is used to expel air from inside the cuff 3 after blood pressure measurement.

[0043] The blood pressure monitor control unit 17 includes: a pump control circuit 31 for controlling the pressurization pump 7; an amplification circuit 32 for receiving the output signal from the pressure sensor 12; a pressure wave separation circuit 33 for receiving the output signal from the pressure sensor 13; an amplification circuit 34 connected to the quick exhaust valve 16; an amplification circuit 35 for receiving the output signal from the microphone 4; a setting display unit 36 ​​for performing various settings and displays; and a CPU 37 electrically connected to these components.

[0044] The blood pressure monitor control unit 17 controls the pressurization pump 7 based on the detection results of the pressure sensor 12. Specifically, when pressurizing the cuff, the blood pressure monitor control unit 17 controls the pressurization pump 7 based on the detection results of the pressure sensor 12. For example, the blood pressure monitor control unit 17 controls the pressurization pump 7 in a manner that increases the pressure of the cuff 3 at a constant rate, regardless of the size of the cuff 3. In addition, the blood pressure monitor control unit 17 controls the pressurization pump 7, for example, in the following manner: after starting to measure blood pressure, the pressure of the cuff 3 is rapidly increased until the cuff 3 lightly contacts the measurement site 2 (for example, until the pressure of the cuff 3 reaches about 20 mmHg to 30 mmHg), and then the pressure of the cuff 3 is increased at a constant rate that is slower than when pressurizing rapidly.

[0045] The blood pressure monitor control unit 17 stores pre-stored reference inflation tilt data for increasing the pressure of the cuff 3 at a constant rate. The blood pressure monitor control unit 17 controls the inflation pump 7 based on the detection results of the pressure sensor 12 and the reference inflation tilt data to increase the pressure of the cuff 3 at a constant rate. The inflation rate of the cuff 3 also depends on the heart rate of the subject or, in the case of experimental animals, is typically set to approximately 2 mmHg to 5 mmHg / second.

[0046] Using the blood pressure monitor 1, blood pressure can be measured when the cuff 3 is inflated. Additionally, the blood pressure monitor 1 can also be used to measure blood pressure when the cuff 3 is deflated. When measuring blood pressure while the cuff 3 is inflated, air is supplied to the inside of the cuff 3 in a manner that increases the pressure at a constant rate. When measuring blood pressure while the cuff 3 is deflated, after the pressure in the cuff 3 has increased to a predetermined pressure, the intermediate vent valve 14 is opened, and air is discharged from the air canister 8 at a constant rate.

[0047] When measuring blood pressure, a pressure fluctuation signal is output from the barometric pressure sensor 13 as a blood pressure detection signal. This pressure fluctuation signal is based on a pulse wave signal that overlaps with the pressure of the cuff 3. The pressure wave separation circuit 33 amplifies the blood pressure detection signal output from the barometric pressure sensor 13 and separates the amplified blood pressure detection signal into a pressure signal and a pulse wave signal. The CPU 37 determines the blood pressure based on the pulse wave signal input from the pressure wave separation circuit 33 and displays the determined blood pressure on a designated display unit. The pressure signal output from the pressure wave separation circuit 33 is a pressure signal corresponding to the pressure where the pulse wave effect of the measured part 2 is reduced (i.e., the pressure close to the pressure of the cuff 3 itself).

[0048] Additionally, when measuring blood pressure, Korotkoff sounds (blood flow sounds, hereinafter referred to as "K sounds") output from microphone 4 are used. Specifically, when measuring blood pressure while inflating cuff 3, the blood pressure at the onset of the K sound after inflating is set as the diastolic pressure (low pressure), and the blood pressure at the cessation of the K sound is set as the systolic pressure (high pressure). Conversely, when measuring blood pressure while deflating cuff 3, the blood pressure at the onset of the K sound after deflating is set as the systolic pressure, and the blood pressure at the cessation of the K sound is set as the diastolic pressure.

[0049] (Main effects of this implementation method)

[0050] As explained above, in this embodiment, an air canister 8 and air filters 10 and 11 are arranged in the air supply path from the pressurizing pump 7 to the cuff 3. Therefore, in this embodiment, the air canister 8 and air filters 10 and 11 reduce the variation in airflow (or air pressure) supplied from the pressurizing pump 7 to the cuff 3. Thus, in this embodiment, the variation in airflow supplied from the pressurizing pump 7 to the cuff 3 is less likely to manifest as a variation in pressure inside the cuff 3, resulting in the ability to measure blood pressure when the cuff 3 is pressurized.

[0051] In this embodiment, the air flowing from the pressurizing pump 7 into the air canister 8 bypasses the air filters 10 and 11 and flows into the air chamber 23, which is positioned closer to the pressurizing pump 7 than all the air filters 10 and 11 in the air supply path from the pressurizing pump 7 to the cuff 3. Therefore, in this embodiment, the pressurizing pump 7 is less likely to be subjected to a large load when pressurizing the cuff 3 via the air canister 8. Thus, in implementing this method, blood pressure can be measured while pressurizing the cuff 3, and the lifespan of the pressurizing pump 7 can be extended.

[0052] In this embodiment, the blood pressure monitor 1 includes a pressure sensor 12, which detects the air pressure inside the air canister 8 disposed in the air supply path from the pressurization pump 7 to the cuff 3. The blood pressure monitor control unit 17 controls the pressurization pump 7 based on the detection result of the pressure sensor 12. Therefore, in this embodiment, the pressurization rate of the cuff 3 can be controlled.

[0053] In this embodiment, since the pressure sensor 12 detects the air pressure in the air chamber 24, which is positioned closer to the pressure pump 7 than the air filter 11, in the air supply path from the pressure pump 7 to the cuff 3, the detection result of the pressure sensor 12 is less susceptible to the influence of pulse waves from the measured part 2 due to the action of the air filter 11. Furthermore, in this embodiment, since the pressure sensor 12 detects the air pressure in the air chamber 24 formed between the air filter 10 and the air filter 11, the detection result of the pressure sensor 12 is less susceptible to the influence of changes in the flow rate of the air supplied from the pressure pump 7 due to the action of the air chamber 23 and the air filter 10. Therefore, in this embodiment, the pressurization speed of the cuff 3 can be controlled with high precision based on the detection result of the pressure sensor 12.

[0054] (Example of a change in a blood pressure monitor)

[0055] Figure 3 This is a simplified diagram illustrating the configuration of a blood pressure monitor 1 according to another embodiment of the present invention. Figure 4 It is used for explanation Figure 3 The diagram shown illustrates the structure of the blood pressure monitor 1.

[0056] In the above embodiments, such as Figure 3 , Figure 4 As shown, the blood pressure monitor body 5 may also not have a pressure sensor 12. Figure 3 , Figure 4 In the modified example shown, the blood pressure monitor body 5 does not have an air filter 10, and the interior of the air tank 8 consists of an air chamber 40 and a connecting chamber 25. Furthermore, in this modified example, the intermediate exhaust valve 14 and the constant speed exhaust valve 15 are connected to the air chamber 40 via an air tube 26.

[0057] In this modified example, the pressure signal output from the pressure wave separation circuit 33 is input to the pump control circuit 31. The blood pressure monitor control unit 17 controls the pressurization pump 7 when the cuff 3 is pressurized based on the pressure signal output from the pressure wave separation circuit 33. In this modified example, since the pressurization pump 7 is controlled based on the pressure signal whose pulse wave influence at the measured part 2 is reduced, the pressurization rate of the cuff 3 can be controlled with high precision.

[0058] (Other implementation methods)

[0059] In the above embodiment, the blood pressure monitor 1 may also be without the microphone 4. In this case, when measuring blood pressure while the cuff 3 is inflated, it is difficult to detect diastolic blood pressure from the pulse signal during the inflation of the cuff 3. However, if the inflation is further increased, the pulse signal becomes larger, and its maximum point becomes the mean blood pressure. In addition, systolic blood pressure is continued to be measured. Diastolic blood pressure is calculated based on systolic blood pressure and mean blood pressure.

[0060] In the above embodiments, the air filter 11 may be disposed outside the air tank 8, or the connecting chamber 25 may not be formed inside the air tank 8. In these cases, for example, one end of the air pipe 27 is connected to the air filter 11. Furthermore, in the above embodiments, three or more air filters may be disposed inside the air tank 8, forming three or more air chambers inside the air tank 8.

[0061] In the above embodiment, the blood pressure monitor body 5 may also omit the air filter 10. In this case, such as Figure 3 As shown, the interior of the gas tank 8 consists of a gas chamber 40 and a connecting chamber 25. Furthermore, in this configuration, the pressure sensor 12 functions to detect the pressure in the gas chamber 40. Additionally, in... Figure 3 , Figure 4 In the modified example shown, the blood pressure monitor body 5 may also include an air filter 10.

[0062] In the above embodiment, the air chamber 23 may not be formed inside the air tank 8. In this case, for example, one end of the air pipe 26 is connected to the air filter 10. Alternatively, in the above embodiment, an air filter may be provided in the air supply path from the pressurizing pump 7 to the air tank 8. In this case, for example, the air filter 10 may not be provided inside the air tank 8.

[0063] In the above embodiment, blood pressure can also be measured using the sphygmomanometer 1 only when the cuff 3 is inflated. When measuring blood pressure while the cuff 3 is deflating, it is typically necessary to rapidly inflate the cuff 3 to a constant pressure of approximately 150 mmHg, thus requiring a large inflator pump 7. However, when measuring blood pressure only while the cuff 3 is inflated, rapid inflation is not required, allowing for a smaller inflator pump 7. However, when the cuff 3 is large, the inflation rate of the cuff 3 can sometimes decrease drastically when inflating up to approximately 300 mmHg, therefore, it is necessary to select an inflator pump 7 suitable for the cuff 3.

Claims

1. A blood pressure monitor, a non-invasive blood pressure monitor for measuring blood pressure, characterized in that it comprises: A cuff is wrapped around the area being measured. A pressure pump is used to supply air to the cuff; and An air tank and air filter are positioned in the air supply path from the pressurization pump toward the cuff. An air chamber is formed inside the air tank, and this air chamber is positioned closer to the pressure pump than all the air filters in the air supply path from the pressure pump to the cuff. Air flowing from the pressurization pump into the gas tank flows into the gas chamber.

2. A blood pressure monitor, a non-invasive blood pressure monitor for measuring blood pressure, characterized in that it comprises: A cuff is wrapped around the area being measured. A pressure pump is used to supply air to the cuff; An air tank and an air filter are disposed in the air supply path from the pressurization pump toward the cuff; The first pressure sensor is used to detect the internal pressure of the gas tank; The second pressure sensor is used to detect the air pressure inside the cuff; as well as The blood pressure monitor control unit includes a pump control circuit for controlling the pressurization pump. An air chamber is formed inside the air tank, and the air chamber is positioned closer to the pressure pump than at least one of the air filters in the air supply path from the pressure pump to the cuff. The first pressure sensor detects the air pressure in the air chamber. The blood pressure monitor control unit controls the pressurization pump based on the detection result of the first air pressure sensor.

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