JPS61284231A - Electronic hemomanometer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to an electronic blood pressure monitor, and particularly to an electronic blood pressure monitor that determines blood pressure values by detecting Korotkoff sounds (K sounds).

(B) Conventional technology In general, electronic blood pressure monitors that determine blood pressure by detecting K-sounds wrap the cuff around the upper arm, pressurize the cuff to block blood flow in the artery, and then slowly evacuate the cuff. Occurs during the process
When the sound disappears, it is detected by a microphone, and the cuff pressure corresponding to the time when the sound occurs and disappears is measured, respectively.
The lowest blood pressure has been determined.

On the other hand, (1) the user feels more confident in the device, (2) the sound has a softer tone that makes them feel calmer, and (2) specialists such as doctors can extract important information from the sound that could not be extracted conventionally. Because of this advantage, an electronic blood pressure monitor that allows the K sound to be directly heard has been created and has already been proposed.

(c) Problems to be Solved by the Invention The electronic blood pressure monitor that allows the above-mentioned sound to be heard simply outputs the output signal from the sound sensor through an amplifier and from a speaker. Even in the part of
There is a problem in that the extra noise is output, which is not only harsh on the ears, but also makes it impossible to hear only the sound that is required.

In view of the above, it is an object of the present invention to provide an electronic blood pressure monitor that outputs a sound only in the range where the K sound appears, thereby reducing noise output.

(d) Means and actions for solving problems in general, K
It is well known that sounds appear in synchronization with heart sounds and electrocardiograms, and that the heart sounds and electrocardiograms precede the sounds. Focusing on this point, the electronic blood pressure monitor of the first invention includes a cuff, a pneumatic system for pressurizing and depressurizing the cuff, a cuff pressure sensor for detecting the cuff pressure, a sound sensor attached to the cuff, and a pneumatic system for increasing and decreasing the pressure of the cuff. a blood pressure determining means for determining a blood pressure value based on the cuff pressure detected by the pressure sensor and the sound detected by the sound sensor; a heart sound sensor;
gate signal generation means for generating a gate signal synchronized with the heart sound signal obtained from the heart sound sensor; gate means for allowing the sound detected by the sound sensor to pass only during the period in which the gate signal is generated; and audio output means for outputting sound from the gate means. Moreover, the electronic blood pressure monitor of the second invention uses an electrocardiogram sensor instead of the heart sound sensor of the first invention.

With these electronic blood pressure monitors, when blood pressure measurement starts with a heart sound sensor (electrocardiogram sensor) attached to the body, a gate signal is generated in synchronization with the heart sound (electrocardiogram) signal input from the heart sound sensor (electrocardiogram sensor). is generated by the gate signal generating means, and only during the period when this gate signal is applied, the K sound passes through the gate means and is output from the audio output means. No sound is output during the period when no gate signal is applied.

(e) Examples These inventions will be explained in more detail below using examples.

FIG. 1 is an external perspective view of an electronic blood pressure monitor according to an embodiment of the first invention. The electronic blood pressure monitor of this embodiment consists of a main body 1 and a cuff (arm cuff) 2, and a display section (LC) is provided on the upper surface of the main body 1.
D) 3, power switch 4, clear switch 5, start switch 6, pressurization setting value changeover switch 7 and speaker 8
is established and provided. Furthermore, a heart sound sensor 9 is connected to the main body 1.

This heart sound sensor 9 includes a heart sound microphone 9b provided on a belt 9a that is worn around the chest. Note that 9c is a fastener for adhesively fixing the band 9a.

Further, inside the case of the main body 1, an MPU (microprocessor unit), other electronic circuits, a pressure pump, etc. are provided.

FIG. 2 is a circuit block diagram of an example electronic blood pressure monitor,
The same numbers as in FIG. 1 indicate corresponding components and circuits.

The cuff 2 is connected to a slow exhaust valve 12 , a pressure pump 13 , and a pressure sensor (cuff pressure sensor) 14 through a rubber tube 11 . This rubber tube 11? A pneumatic system 15 is composed of an m-speed exhaust valve 12, a pressurizing pump 13, and the like. Further, a microphone (K sound sensor) 16 is attached to the cuff 2 for detecting sound.

The inside of the cuff 2 is pressurized by a pressure pump 13, and the internal pressure is converted into an electrical signal (analog) by a pressure sensor 14, amplified by an amplifier 17, and further converted into a digital signal by an A/D converter 18. , are taken into MPU19.

The sound detected by the microphone 16 is amplified by an amplifier 20 and applied to a K sound filter/comparator 21 and a speaker switch 22. The K sound filter/comparator 21 passes only the frequency component of the K sound, and turns ON when a predetermined level or higher is input.
Output a signal.

This ON signal is taken into the MPU 19 as a sound presence signal.

The speaker switch 22 is opened and closed by a command from the MPU 19, and when it is turned on, sound is emitted from the speaker switch 2.
2. The signal is outputted from the speaker 8 after passing through the amplifier 23. This speaker switch 22 is turned on when measurement starts after the pressurization is stopped, and turned off when the measurement is finished.

The heart sound sensor 9 is connected to the terminal 24. Further, the heart sound signal obtained at this terminal 24 is transmitted to the amplifier 2.
5. Through the heart sound filter/comparator 26, the MPU1
It is now being incorporated into 9.

Next, the functional configuration and operation of the electronic blood pressure monitor of the above embodiment will be explained with reference to the flowcharts shown in FIGS. 3 and 4.

When the power switch 4 is turned on, first the display (LCD)
) 3 for 2 seconds [step ST (hereinafter abbreviated as ST) 1], then turn off all segments of the display 3 (5T2), and check the display 3.

Next, the exhaust mark 8 on the display 3 blinks (5T3),
5T4 to encourage evacuation of cuff 2 and determine whether the cuff pressure is O or not.
), when the cuff pressure reaches 0, the exhaust mark 8 turns off (S
r5). Then, this time, the ready mark 9 on the display 3 is turned on (Sr6).

・Subsequently, it is determined whether the start switch 6 has been turned on.

After the measurer attaches the cuff 2 to his upper arm, when he visually observes that the ready mark 9 is lit, he turns the start switch 6 ON.
, this will start pressurization before measurement.

That is, when the start switch 6 is turned on, Sr7
If the determination is YES, then the slow exhaust valve 12 is closed and the pressurizing pump 13 is driven to pressurize the cuff to the pressurization setting value (Sr8). When the pressure is increased to a predetermined set value, the process starts measurement, that is, blood pressure measurement and display processing (Sr1). This process will be detailed later. Once blood pressure measurement is complete,
After exhausting the air (STIO) and completing the series of operations, the system returns to Sr3 and waits for the next measurement.

When the process moves to the blood pressure measurement process of Sr1, as shown in FIG. 4, first, it is determined whether the heart sound comparator 26 is OFF (STII). The heart sound level is shown in Figure 5 (al
If the threshold value TH shown in is exceeded, this judgment is N.
o, and waits for a period of time in step 5TII. Thereafter, if the heart sound level becomes below the threshold TH, or if it has been below the threshold TH from the beginning, the determination of 5TII becomes YES'S, and then the heart sound comparator 26 goes to 0.
It is determined whether or not it is N (ST12). As long as the heart sound level does not exceed the threshold value, this determination is No, and then it is determined whether or not the clear switch 5 is ON (ST13). This determination is also No unless the clear switch 5 is operated, and then it is determined whether the cuff pressure is 20 mmHg or less (
ST14). In a state where SYS (systolic blood pressure) is not determined, the cuff pressure is normally 20 mmHg or more, so the determination of 5T14 is NO, and the process returns to 5T12. Then, until the heart sound comparator 26 is turned on, that is, until the heart sound level exceeds the threshold, 5T12.5T1
3.5T14 will be repeated.

As shown in Figure 5 (al), the heart sound level is at the threshold TH.
When the heart sound comparator 26 exceeds ONL, 5T12
The determination is YES, the speaker switch 22 is turned on (ST15), and the 200 m5ec timer is started (ST16), that is, the gate signal is triggered. This 200 m5ec determines the ON period of the speaker switch 22, and corresponds to the ON period of the heart sound gate signal shown in Figure 5).

Next, it is determined whether the K sound comparator 21 is ON or not (
ST17), since no sound is detected by the microphone 16 at the beginning of the measurement, this determination is N.

, and then whether clear switch 5 is ON (ST18)
, a judgment is made as to whether the cuff pressure is 20 mm and 11 g or less (ST19), but as mentioned above, these judgments are usually N.
o, and then it is determined whether or not the 200m5ec timer has timed up (ST20). If the timer has not timed up, the process returns to 5T17, and the 200m5ec timer continues until the timer times up, that is, after the speaker switch 22 is turned on.
The process of 5T17, .

When the 200m5ec timer times up, 5T20
The determination becomes YES, the gate signal is turned OFF, and the speaker switch 22 is turned OFF (ST21).
. Then, it is determined whether the SYS has been determined (ST22),
If SYS has not been determined yet, the process returns to 5T12. In a state where the K sound has not been detected yet, naturally SYS has not been determined either, so the process returns to 5T12. Then, 5T12 until the heart sound level reaches the threshold TH.
......, waits for a time at 5T14. If the heart sound level exceeds the threshold TH again, the determination of 5T12 is Y.
It becomes ES and the speaker switch 22 is turned ONL.

(ST15) and starts a 200m5ec timer (ST16). After that, the K sound comparator 21 is turned ON.
5T12 until the sound is detected.
..., the process of 5T22 is repeated.

When the K sound comparator 21 turns on, the determination of 5T17 becomes YES, and then it is determined whether the SYS has been determined (
ST23). When the K sound comparator 21 turns on for the first time, that is, when the first sound is detected, this determination is No, and the cuff pressure at that time is determined to be SYS and stored (5T24), S
YS is displayed on the display 3 (ST25). Next, or if the sys has already been determined and the determination in 5T23 is YES, display the current cuff pressure on the display 3 (ST26), 2
It waits until the 0Q m5ec timer times up (5T27), and when it times up, turns off the speaker switch 22 (S728) and returns to STI 1.

5TII, as described above, heart sound comparator 2
6 is OFF, and if it is still heart sound comparator 2.
6 is ON, that is, when the heart sound level is higher than the threshold value TH, s'r continues until the heart sound comparator 26 turns OFF.
Stay at ii and wait. Then, when the heart sound comparator 26 turns OFF, it stays at 5TI2, 5T14 until the next heart sound turns ON, and when the heart sound comparator 26 turns ON at the 0th order heart sound, the speaker switch 22 is turned ON ( ST15), 200m5e
c Start the timer (STI 6), then 5TI
7, . . . , 5T28. Repeat the process of 5TII to continue detecting the K sound.

When the cuff pressure decreases and the K sound comparator 21 turns OFF, that is, the sound disappears, 5T17 becomes NOl and after 200 m5ec passes, ST, 20 becomes YES, and the speaker switch 22 is turned OFF (ST21).
Next, in 5T22, it is determined whether the SYS has been determined. Since this judgment is YES, the cuff pressure at that point is DI.
The DIA is determined and stored as A (diastolic blood pressure) (ST29), and the DIA is displayed on the display 3 (ST"30). This completes the measurement.

Furthermore, if it is desired to interrupt the measurement during the measurement, the clear switch 5 may be turned on. Now the judgment of 5TI3 and 5T1B becomes YES, and then turn the speaker switch 22 OFF.
F (ST31) and end the measurement.

In addition, during the above measurement, if the cuff pressure becomes 20 mm 1 g or less for some reason even though SYS has not been determined, the determination of 5T14 or 5T19 becomes YES, and it is assumed that measurement is impossible, and the speaker switch 22 is then turned on. OF
F (ST21), and the measurement is also ended.

Furthermore, in the above embodiment, the signal output from the amplifier 20 has the waveform shown in FIG. The speaker switch 22 is shown in FIG. 5(b).
Since it is turned on by the gate signal shown in Figure 5 (d+), the sound output from the speaker 8 has the waveform shown in Figure 5 (d+), and the signal is output from the speaker 8 except for the period in which the sound appears, that is, the gate period. Therefore, unnecessary noise other than the K tone is removed.

Next, an electronic blood pressure monitor according to a second embodiment of the invention will be described.

The electronic blood pressure monitor of this embodiment uses an electrocardiogram sensor in place of the heart sound sensor 9 of the electronic blood pressure monitor of the embodiment shown in FIGS.
6, an electrocardiogram filter comparator is used. The other parts are the same as the electronic blood pressure monitor of the above embodiment using a heart sound sensor. Therefore, the external view and circuit diagram of this embodiment of the electronic blood pressure monitor will be omitted.

As shown in FIG. 6, the electrocardiographic sensor 39 has a pair of electrodes 39b on a band 39a that is worn around the chest.

39c is provided, and these electrodes 39b and 39c are connected to the electronic blood pressure monitor 1 via a lead wire 39d. Note that 39e is a fastener for adhesively fixing the band 39a.

The processing flow when measuring blood pressure is also 5T of the flow shown in Figure 4.
By changing the determination of "Is the heart sound converter OFF" in II and the determination of "Is the heart sound comparator ON" in 5T12 to "Is the electrocardiogram comparator OFF" or "Is the electrocardiogram comparator ON"? Then, as shown in Fig. 7, if the gate signal is triggered at the point where the electrocardiogram waveform exceeds the threshold TH [see Fig. 7 (a)] and a gate signal of 200 m5ec is obtained, [7 Figure 5(C) shows a signal containing only the gate period of a sound signal including similar noise, and in other words, the same signal as shown in FIG. 5(d) is output from the speaker 8. Ru.

In the above embodiment, a pressure horn is used to pressurize the cuff, and the pressure is automatically applied, but manual pressure may be applied using a rubber ball or the like.

Furthermore, earphones may be used as the audio output means instead of a speaker.

Further, by drawing the output waveform of the heart sound sensor or electrocardiogram sensor on the display, this electronic blood pressure monitor can be used as a phonocardial monitor or an electrocardiogram monitor.

(f) Effects of the invention According to these inventions, a gate signal synchronized with a heart sound signal or an electrocardiogram signal is created, a sound is outputted as an audio through this gate signal, and the sound is output only during the period in which the K sound appears. Since it has been made audible, you can remove unnecessary noise and only hear the sound.

Moreover, it is also possible to observe the heart sound waveform and the electrocardiogram waveform themselves using a heart sound sensor or an electrocardiogram sensor.

[Brief explanation of the drawing]

FIG. 1 is an external perspective view of an electronic blood pressure monitor according to an embodiment of the first invention, FIG. 2 is a circuit block diagram of the electronic blood pressure monitor, and FIG. 3 is a schematic overall control of the electronic blood pressure monitor. Flowchart, FIG. 4 is a control flowchart showing the blood pressure measurement/display routine of the overall control flow in more detail, and FIG. 5 is a waveform diagram for explaining the operation of the electronic blood pressure monitor of the above embodiment. Figure 6 shows
FIG. 7, which is a plan view of an electrocardiographic sensor used in the electronic blood pressure monitor according to the second embodiment of the invention, is a waveform chart for explaining the operation of the electronic blood pressure monitor according to the second embodiment. 2: Cuff, 8: Speaker, 9: Heart sound sensor, 14: Pressure sensor, 15: Pneumatic system, 16 Microphone, 19: MPU,
22: Speaker switch, 25: Heart sound filter/comparator, (electrocardiogram filter/comparator) 39: Electrocardiogram sensor. Patent applicant Tateishi Electric Co., Ltd. Agent
Patent Attorney Shigeru Nakamura Shinsuke 4M Figure 5 Figure 7

Claims (2)

[Claims] (1) A cuff, a pneumatic system that pressurizes and depressurizes the cuff, a cuff pressure sensor that detects cuff pressure, a Korotkoff sound sensor attached to the cuff, and a cuff pressure and Korotkoff sound sensor that are detected by the cuff pressure sensor. An electronic sphygmomanometer comprising: a blood pressure determining means for determining a blood pressure value from detected Korotkoff sounds; a heart sound sensor; a gate signal generating means for generating a gate signal synchronized with a heart sound signal obtained from the heart sound sensor;
An electronic sphygmomanometer comprising: gate means for allowing the Korotkoff sound detected by the Korotkoff sound sensor to pass only during the period in which the gate signal is generated; and audio output means for outputting the Korotkoff sound from the gate means. (2) A cuff, a pneumatic system that pressurizes and depressurizes the cuff, a cuff pressure sensor that detects cuff pressure, a Korotkoff sound sensor attached to the cuff, and a cuff pressure and Korotkoff sound sensor that are detected by the cuff pressure sensor. An electronic sphygmomanometer comprising: a blood pressure determining means for determining a blood pressure value from detected Korotkoff sounds; ,
An electronic sphygmomanometer comprising: gate means for allowing the Korotkoff sound detected by the Korotkoff sound sensor to pass only during the period in which the gate signal is generated; and audio output means for outputting the Korotkoff sound from the gate means.