JP2002224062A - Sphygmomanometer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure blood pressure in a state of minimizing influence of noise. SOLUTION: This hemodynamometer has a pressing sac part of a measuring part on a cuff 1 installed in the measuring part, and measures the blood pressure by taking out vibration information on a living body from a pressure change in the sac part. The cuff 1 is provided with a second sac part 11 independent of the pressing sac part 12 of the measuring part. A pressure sensor is connected to the second sac part 11 having a closed space. The sensing sac part 11 is separated and made independent from the pressing sac part 12 to be little influenced by unnecessary vibration in the pressing sac part 12 for pressurizing and reducing internal pressure of the sensing sac part 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sphygmomanometer, and more particularly to a sphygmomanometer that measures a blood pressure by extracting a pulse wave from a pressure change in a sac portion of a cuff.

[0002]

2. Description of the Related Art A sphygmomanometer for measuring blood pressure by an oscillometric method generally comprises, as shown in FIG. 21, an arm band 1 containing a sac portion 10 and an arm band 1 by blowing air into the sac portion 10. Pump 2 for compressing the measurement site around which is wound, and sac 1
A gradual exhaust valve 3 for gradually exhausting the air in the chamber 0, a rapid exhaust valve 4 for opening the inside of the sac portion 10 to the atmospheric pressure at the end of the measurement or when the measurement is not being performed, and an internal pressure of the sac portion 10. A pressure sensor 5 for measurement, and an output signal of the pressure sensor 5 are A
The control circuit MPU receives the data via the / D conversion circuit 60, calculates the blood pressure value, controls the operation of the rapid exhaust valve 4, the gradual exhaust valve 3, and the pump 2, and displays 61 for displaying the blood pressure value. , A power supply circuit 62, a buzzer 63 for notification, and the like.

FIG. 22 shows a cross section of the above-mentioned arm band 1,
The encapsulated sac 10 is connected to the pressure sensor 5, the exhaust valves 3 and 4, the pump 2 and the like through the connection plug 19.

In measuring blood pressure, the arm band 1 is used as a measuring unit,
For example, wrap it around an arm or wrist, etc.
The pressure is applied to the measurement portion by the arm band 1 and then the air in the sac portion 10 is gradually released to lower the pressure. At this time, a pulse wave (see FIG. 24) is extracted from the change in the internal pressure of the sac 10 as shown in FIG. 23 detected by the pressure sensor 5, and before and after the blood flow is generated in the change in the pulse wave component. Blood pressure is determined by sensing a point at which a characteristic change occurs at the corresponding pressure.

[0005]

In the arm band 1 of the conventional blood pressure monitor, the bladder 10 for compressing the measurement unit with the pressurized air is also connected to the pressure sensor 5.
Noise due to the pump 2 for pressurization is superimposed, noise at the time of exhaustion is superimposed, and furthermore, impact vibrations due to pulsation from the central side before and after blood flow generation of the human body are superimposed as noise. Causes errors in blood pressure measurements.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a sphygmomanometer capable of performing a blood pressure measurement with high accuracy while minimizing the influence of noise. It is in.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a compression band in the arm band attached to the measurement unit, and extracts blood pressure information of a living body from a pressure change in the bag to measure blood pressure. In the sphygmomanometer to be measured, a second sac section independent of the compression sac section of the measurement section is provided on the arm band, and the pressure sensor is connected to the second sac section having a closed space. It has features. The sensing sac is separated from the compression sac to make it independent of unnecessary vibrations in the compression sac where the internal pressure of the sensing sac is increased / decreased.

Preferably, the pressure sensor is connected to the second sac via a flexible member. Further, it is preferable that the second sac portion to which the pressure sensor is connected is filled with an incompressible and low-viscosity material.

It is preferable to connect a pressurizing means to the compression sac of the measuring section via a vibration preventing means. At this time, it is preferable to use a resistance component or a capacitance component for the vibration preventing means. it can.

A digital signal processing means for separating the output of the pressure sensor into a DC component and an AC component may be provided. At this time, an analog filter, especially 0.5 to 20 Hz, is provided before or after the digital signal processing means. A band-pass type that passes a band may be used.

[0011] It is also preferable to provide a vibration absorbing means in a portion of the measuring section to which the arm band is attached, on the side closer to the center of the human body than the contact section of the second capsule section. A shock absorbing material can be suitably used for the vibration absorbing means. The second bag may be filled with vibration absorbing means.

It is preferable that the position of the pressure sensor with respect to the arm band is variable.

[0013] Further, a correction means for correcting the blood pressure value based on the initial offset value at the reference position of the pressure sensor is provided, or the blood pressure value is corrected from the offset value before the measurement and the offset value after the measurement. When the correction means is provided, more accurate measurement can be performed. It is preferable that the correction means here performs correction by subtracting the correction value from the provisional blood pressure value calculated at the time of measurement, using the difference between the initial offset value and the offset value after measurement as the correction value. It is also preferable to have a function of periodically calculating and calibrating the initial offset value.

Further, in the case of a sphygmomanometer having a wrist as a measuring unit, the position of the second capsule connected to the pressure sensor may be variable with respect to the arm band.

[0015] It is preferable that the second sac is disposed on the position of the radial artery or the position of the ulnar artery.

It is preferable that a plurality of second bag portions independent of each other are provided, and a blocking means for blocking information between the second bag portions is provided. In this case, the blocking means has rigidity. It is possible to suitably use a shielding plate or a cushioning material having the same.

In addition, the second capsule connected to the pressure sensor can be suitably elongated in the wrist axis direction or elongated in the wrist circumferential direction.

[0018] It is also preferable that the second sac connected to the pressure sensor is surrounded by a compression sac.

A means for judging the winding force by comparing the initial offset value of the pressure sensor before winding the arm band around the measuring section with the offset value of the pressure sensor after winding the measuring arm around the measuring section; It is also preferable to do so.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to an example of an embodiment. As shown in FIG. Are provided with two sac portions 11 and 12 and are independent of each other.
The pressure sensor 5 is connected to the small-capacity sac 11 and the pump 2 is connected to the large-capacity sac 12 with the internal space completely closed.
And exhaust valves 3 and 4 are connected. The sac portion 12 has an exhaust valve 3,
4 to be open to the atmosphere.

In the drawing, reference numeral 13 denotes a tube connecting the internal space of the cap section 11 to the pressure sensor 5, and reference numeral 14 denotes a tube connecting the internal space of the cap section 12 to the pump 2 and the exhaust valves 3 and 4. . The main body including the sensor 5, the pump 2 and the like and having the display 61 and the like and the armband 1 are connected via the flexible tubes 13 and 14, so that the position can be changed redundantly for each measurement. This is because the installation position can be freely changed. However, the main body may be provided on the arm band 1. Here, the output of the pressure sensor 5 is converted to an A / D conversion circuit 6 in the same manner as in the conventional example.
0 is connected to the control circuit MPU.
The D conversion circuit 60 may not be provided, or the control circuit MPU may be one-chip.

FIG. 2 shows the sac portions 11 and 1 in the arm band 1.
2 shows an example of the arrangement. On one end of the arm band 1, which is slender and can be wound around a measuring part such as an arm or a wrist,
By arranging the bag portions 11 and 12 long in the longitudinal direction of the arm band 1 in the short direction of the arm band 1 so that the both bag portions 11 and 12 do not overlap in the thickness direction of the arm band 1, The possibility that slight fluctuations in the pressure in the portion 12 affect the pressure in the bladder portion 11 is reduced.

The pressure sensor 5, the capsule portion 11 and the tube 13 contain an incompressible low-viscosity medium such as water.
It may be filled with low-viscosity gel, lubricating oil or the like. The transmission of pressure to the pressure sensor 5 can be improved.

In order to suppress the minute fluctuation of the pressure in the sac portion 12 caused by the pump 2, as shown in FIG. 3, an anti-vibration means 15 is disposed in an air passage between the pump 2 and the sac portion 12. Good. As the vibration isolating means 15, one having a resistance, for example, as shown in FIG. 4, a tube 15a having a small cross-sectional area provided in the middle of the tube 14 or a damper having a capacitance, for example, As shown in FIG. 5, a tank 15b having a larger capacity than the tube 14 can be used.

FIG. 6 shows another example. Here, the control circuit MP
A digital signal processing unit is provided in a U (microcomputer), and the digital signal processing unit separates the AC and DC components of the output of the pressure sensor 5 in numerical calculation. In this case, as shown in FIG. 7, an analog filter 64 for removing a signal component that cannot be removed by digital signal processing may be provided before the A / D conversion circuit 60. The analog filter 64 has a frequency band of less than 30 Hz, preferably 0.5 Hz.
A band-pass type that passes a band of ２０20 Hz is preferable. This is because the necessary information included in the signal components is up to the frequency component of the pulse wave, and no more frequency components are necessary. Note that the analog filter 64 may be inserted after the digital signal processing.

FIG. 8 shows another example. This is to prevent unnecessary vibration from the central side (body side) of the body from affecting the pressure change in the sac portion 11, so that unnecessary vibration from the central side (body side) of the body when attached to the measurement section at the edge of the arm band 1 A cushioning material 7 for absorbing vibration is provided on the side where the cushioning member 7 comes in contact with the measuring unit when the arm band 1 is attached to the measuring unit (the wrist in the illustrated example). , Such as vibrations associated with shock waves received from the upstream of the artery. The cushioning material 7 may be any material as long as it can absorb and attenuate a specific frequency component (vibration caused by a pulse wave, for example, 0.2 Hz or more). In addition, the cushioning material 7 is a sac 11
When the arm band 1 is wound around the measurement portion, the capsule portion 12 is located on the central side and the capsule portion 1 is located on the distal side.
As long as 1 is located, cushioning material 7 may be arranged between sac portion 12 and sac portion 11, and furthermore, cushioning material 7 may be arranged on the inner peripheral side of sac portion 12. Further, it may be independent from the arm band 1.

FIG. 9 shows still another example. This is armband 1
The figure shows a state in which the bladder portion 11 is arranged at a position located on the inner periphery of one end of the bladder portion 12 in the inside. Such a sac 1
1 can be easily formed by welding the peripheral edge of the sheet to the inner surface side of the bag portion 12. Here, in order to absorb unnecessary vibrations from the central side of the body, a vibration absorbing material such as oil or viscous gel is sealed in the sac portion 11 here.

FIG. 10 shows the pressure sensor 5 connected to the capsule 11 by a flexible tube 13 so that the pressure sensor 5 can be separated from the main body. The figure shows that the position can be freely changed. Although the measured values vary depending on the position of the pressure sensor 5 (height with respect to the measurement unit), the pressure sensor 5 can be positioned at substantially the same height as the measurement unit or at the same height as the heart position.

In terms of absorbing variations due to the height of the pressure sensor 5, as shown in FIG. 11, the output value of the pressure sensor 5 with the pressure sensor 5 placed at the reference position is stored as an offset value X1. At the time of measurement, the output value of the pressure sensor 5 may be corrected based on the offset value X1 at the time of measurement. As shown in FIG. 12, if the offset value A2 after the measurement is measured in addition to the offset value A1 before the measurement as shown in FIG. 12, it can be detected whether the pressure sensor 5 has moved during the measurement. It will be.

FIG. 13 shows an example of the correction by the offset value. The correction value X3 is set to X3 = X2 for the offset value X1 at the reference position and the offset value X2 after the measurement.
-Temporary blood pressure value calculated at the time of measurement and correction value X3 derived by -X1
From this, it is calculated as blood pressure value = temporary blood pressure value−X3. For example, a change in pressure due to gravity due to the relationship between the reference position and the sensor position at the time of blood pressure measurement can be corrected, and blood pressure can be accurately measured.

Further, as shown in FIG. 14, it is possible to inform the user of this after a certain period of time has elapsed, and if there is such notice, the pressure sensor 5 is positioned at the reference position to set the initial offset value X1. By obtaining the offset value, the offset value can be periodically calibrated.

By the way, in addition to the one in which the sac portion 11 is arranged in the arm band 1, the sac portion 11 can be located at an arbitrary position on the inner peripheral side of the arm band 1 by using an adhesive tape or a sheet fastener. Such a configuration may be used. If the position of the sac portion 11 can be changed in this way, as shown in FIG. 15, by changing the position in the longitudinal direction of the arm, the wrist position can be changed, for example, when the measurement site is the wrist position. As a result, it is possible to avoid the obstructive factor at the time of compressing the tendon or the like. Also, as shown in FIG. As shown in FIG. 16B, the sac portion 11 can be positioned on the ulnar artery A2,
This is advantageous for efficient compression and sensing only the arterial signal.

When the sac 11 is located on both the radial artery and the ulnar artery (or, even though the sac 11 does not straddle both arteries, the information of the two arteries is transmitted via the sac 11 to the pressure sensor). 5 if both are detected)
As shown in FIG. 17, it is preferable to perform a blood pressure determination by blocking information transmitted from different paths by frequency-analyzing arterial information (such as a pulse wave) and performing phase separation. An accurate blood pressure measurement can be performed.

In separating arterial information of different routes, as shown in FIG. 18, a portion 11b of the sac portion 11 located on the radial artery and a portion 11b located on the ulnar artery are divided into respective portions. The pressure sensors 5 may be individually provided on the sac portions 11a and 11b via the tubes 13a and 13b. In this case, the two sac portions 11a,
It is preferable to provide a partition filled with a cushioning material or a rigid shielding plate in the portion 11c located between the portions 11b.

As shown in FIG. 19 (a), if the sac portion 11 is elongated along the artery, the artery information can be effectively sensed. In order to avoid the influence of the arterial shock wave, as shown in FIG. 19 (b), it is preferable that the shape is elongated in the circumferential direction of the measuring portion (wrist). Are preferred.

In addition, as shown in FIG. 20, an offset value X1 of the pressure of the sac portion 11 in a state where the arm band 1 is not wound around the measuring portion is obtained and stored, and then wound around the measuring portion at the time of measurement. With the power turned on, the sac 11
The offset value X2 of the arm band 1 is obtained, compared with the offset value X1 stored in advance, and it is determined whether or not this value is equal to or more than a certain value or less than a certain value. It is possible to determine whether the state is too fast or too loose, thereby reducing the influence on the blood pressure determination due to the variation in the wrapping force. In addition, the measurement may be started in all the states, and the winding force may be corrected from the blood pressure determination value.

[0037]

As described above, according to the first aspect of the present invention, the sac portion of the arm band is separated into a sac portion for sensing a signal and a sac portion for compression, and the inside of the sac portion for the sensing is separated. Is a closed space, it is possible to accurately and stably extract a signal to be sensed.

The invention of claim 2 and claims 13 to
According to the seventeenth aspect, the position of the pressure sensor can be freely set, and variation due to the position of the pressure sensor can be reduced.

Further, according to the third to twelfth aspects of the present invention, it is possible to more accurately sense biological information.

According to the inventions of claims 18 to 26, when the measurement site is a wrist site, the arterial information can be accurately sensed without mixing a plurality of signals.

According to the twenty-seventh aspect, it is possible to reduce variations in the winding force of the arm band.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of an embodiment of the present invention.

FIG. 2 is a horizontal sectional view of the arm band in the unfolded state.

FIG. 3 is a block diagram of another example of the above.

FIG. 4 is a horizontal cross-sectional view showing a further expanded state of the arm band of the above.

FIG. 5 is a horizontal cross-sectional view of another example of the above-mentioned arm band in a deployed state.

FIG. 6 is a block diagram of another example.

FIG. 7 is a block diagram of still another example.

FIG. 8 is a front view of another example.

FIG. 9 shows still another example, in which (a) is a perspective view and (b)
Is a horizontal sectional view, and (c) is a vertical sectional view.

FIG. 10 is an explanatory diagram of another example.

FIG. 11 is a flowchart of still another example.

FIG. 12 is a flowchart of another example.

FIG. 13 is a flowchart of still another example.

FIG. 14 is a flowchart of a different example.

FIG. 15 is an explanatory diagram of another example.

FIGS. 16A and 16B are explanatory views of still another example.

FIG. 17 is a flowchart of another example.

FIG. 18 is an explanatory diagram of still another example.

FIGS. 19A and 19B are explanatory diagrams of different examples.

FIG. 20 is a flowchart of still another example.

FIG. 21 is a block diagram of a conventional example.

FIG. 22 is a sectional view of the arm band of the above.

FIG. 23 is a time chart of the output of the pressure sensor.

FIG. 24 is a time chart of the above pulse wave.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Arm band 2 Pump 3 Gradual exhaust valve 4 Quick exhaust valve 5 Pressure sensor 11 Capsule part 12 Capsule part

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Osamu ikukubo 243-108 F-term (reference) 4C017 AA08 AB01 AC03 AD30 BC08 BC16

Claims (27)

[Claims] 1. A sphygmomanometer, comprising: a cuff for a measurement unit provided on a cuff attached to a measurement unit; and measuring blood pressure by extracting vibration information of a living body from a pressure change in the sac.
A second sac section independent of the sac section for compression of the measuring section is provided on the arm band, and a pressure sensor is connected to the second sac section having a closed space. Sphygmomanometer. 2. The pressure sensor according to claim 1, wherein the pressure sensor is connected to the second bag via a flexible member.
Sphygmomanometer as described. 3. The sphygmomanometer according to claim 1, wherein the second capsule connected to the pressure sensor is filled with an incompressible and low-viscosity material. 4. The sphygmomanometer according to claim 1, wherein a pressurizing means is connected to the compression sac of the measuring section via a vibration preventing means. . 5. The sphygmomanometer according to claim 4, wherein the vibration preventing means is a resistance component. 6. The sphygmomanometer according to claim 4, wherein the vibration preventing means is a capacitance component. 7. The sphygmomanometer according to claim 1, further comprising digital signal processing means for separating an output of the pressure sensor into a DC component and an AC component. 8. The sphygmomanometer according to claim 7, wherein an analog filter is provided before or after the digital signal processing means. 9. The sphygmomanometer according to claim 8, wherein the analog filter is a band-pass type that passes a band of 0.5 to 20 Hz. 10. A second measuring section to which a cuff is attached.
2. The sphygmomanometer according to claim 1, further comprising a vibration absorbing means in a portion closer to the center of the human body than the contact portion of the sac portion. 11. The sphygmomanometer according to claim 10, wherein the vibration absorbing means is a cushioning material. 12. A second measuring section to which a cuff is attached.
2. The sphygmomanometer according to claim 1, wherein the sac portion is filled with vibration absorbing means. 13. The sphygmomanometer according to claim 2, wherein the position of the pressure sensor with respect to the arm band is variable. 14. The sphygmomanometer according to claim 2, further comprising correction means for correcting a blood pressure value based on an initial offset value at a reference position of the pressure sensor. 15. The sphygmomanometer according to claim 2, further comprising correction means for correcting the blood pressure value from the offset value before the measurement and the offset value after the measurement. 16. The correction means performs correction by subtracting the correction value from the provisional blood pressure value calculated at the time of measurement, using the difference between the initial offset value and the offset value after measurement as the correction value. The sphygmomanometer according to claim 15, characterized in that: 17. A function for periodically calculating and calibrating an initial offset value.
The blood pressure monitor according to any one of the above items 6. 18. A sphygmomanometer having a wrist as a measuring unit, wherein the position of the second sac connected to the pressure sensor is variable with respect to the arm band.
7. The blood pressure monitor according to any one of items 7 to 7. 19. The sphygmomanometer according to claim 1, wherein the second sac portion is disposed on a position of a radial artery. 20. The sphygmomanometer according to claim 1, wherein the second sac is disposed on the ulnar artery. 21. The method according to claim 1, further comprising a plurality of second bag portions independent of each other, and a blocking means for blocking information between the second bag portions. Sphygmomanometer according to any of the above items. 22. The sphygmomanometer according to claim 21, wherein the blocking means is a rigid shielding plate. 23. The sphygmomanometer according to claim 21, wherein the blocking means is a cushioning material. 24. The sphygmomanometer according to claim 1, wherein the second capsule connected to the pressure sensor is elongated in the wrist axis direction. 25. The sphygmomanometer according to claim 1, wherein the second sac connected to the pressure sensor is elongated in a circumferential direction of the wrist. 26. The sphygmomanometer according to claim 1, wherein a compression sac surrounds the second sac connected to the pressure sensor. 27. A means for evaluating a winding force by comparing an initial offset value of the pressure sensor before winding of the arm band around the measuring section with an offset value of the pressure sensor after winding around the measuring section. 2. The method according to claim 1, wherein
Sphygmomanometer as described.