JP2009022489A - Humidity sensor type apnea detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a humidity sensor type apnea detector capable of surely detecting an abnormal respiration state while suppressing the cost. <P>SOLUTION: This humidity type apnea detector is provided with: a humidity sensor disposed near the oral cavity of a subject and measuring a respiratory cycle by a change in humidity; a normal respiration value storage means calculating and storing a respiration time per cycle out of a continuous respiration cycle indicating a normal-time respiration state, and a variation of an output voltage corresponding to an amplitude value of the respiration as average values; a comparison means for comparing the respiration time and the output voltage variation stored in the storage means with an actually-measured respiration time of the actual respiration state measured by the humidity sensor and an actually-measured output voltage variation corresponding to its amplitude value; a recognition means for recognizing states, where the actually-measured respiration time is deflected from a predetermined range relative to the respiration time in the comparison means and the actually-measured output voltage variation is deflected from a predetermined range relative to the output voltage variation, as an abnormal respiration state of the subject; and a notification means, when the recognition means measures it as the abnormal respiration state, notifying it to the subject or the like. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a humidity sensor type apnea detection device that detects an apnea state using a humidity sensor.

Various devices are being studied and realized as apnea detection devices that measure apnea and other abnormal breathing states. As a conventional apnea detection device, a device that detects the presence or absence of breathing by examining the oxygen concentration in the blood, or a humidity sensor that detects a change in humidity around the oral cavity of the subject as a change in impedance is used. Things.
JP-A-9-262224

However, in order to detect the presence or absence of respiration from the oxygen concentration in the blood, a highly accurate circuit that can detect even a slight change in oxygen concentration is required, which may increase the cost of the apparatus.

In addition, there is a problem that an apparatus that detects a change in humidity as a change in impedance may not be able to detect an abnormal breathing state because the response speed of impedance detection is low.

Accordingly, an object of the present invention is to provide a humidity sensor type apnea detection device capable of reducing the cost of the device with a simple configuration and reliably detecting an abnormal breathing state.

In order to solve the above problems, in the humidity sensor type apnea detection device of the present invention, a humidity sensor that is disposed near the oral cavity of the subject and measures the subject's breathing cycle by a change in humidity, The breathing time per cycle of the continuous breathing cycle indicating the breathing state at the normal time and the change value of the output voltage corresponding to the amplitude value in the breathing at the normal time are respectively calculated and stored as average values. Normal breathing value storage means, breathing time and output voltage change value stored in normal breathing value storage means, actual breathing state measured by the humidity sensor, and actual output corresponding to actual amplitude value In the comparison means for comparing the voltage change value and the comparison means, the measured breathing time is out of a predetermined range with respect to the breathing time, and / or the measured output voltage change value is compared with the output voltage change value. And a recognition means for recognizing a state outside the predetermined range as an abnormal breathing state of the subject, and the subject or observation that the abnormal breathing state is measured when the abnormal breathing state is measured in the recognition means. A notification means for notifying a person.

The humidity sensor type apnea detection device of the present invention further includes a setting unit that changes a predetermined range of the actually measured respiratory time with respect to the respiratory time and / or a predetermined range of the actually measured output voltage change value with respect to the output voltage change value. preferable.

In the humidity sensor type apnea detection device of the present invention, the predetermined range of the measured respiratory time with respect to the respiratory time is in the range of −30% to + 30% of the respiratory time, and the predetermined range of the measured output voltage change value with respect to the output voltage change value. Is preferably in the range of −30% to + 30%.

In the humidity sensor type apnea detection device of the present invention, the humidity sensor preferably detects a change in humidity as a change in capacitance.

In the humidity sensor type apnea detection device of the present invention, the abnormal breathing state is, for example, an apnea breathing state.

In the humidity sensor type apnea detection device of the present invention, the notification means is preferably an alarm device that generates a notification sound to notify.

In the humidity sensor type apnea detection device of the present invention, the notification means can be a lighting device that lights up a notification lamp for notification.

In the humidity sensor type apnea detection device of the present invention, the notification means may be a vibration device that notifies by vibrating a vibrator.

According to the present invention, a humidity sensor that is disposed in the vicinity of the oral cavity of the subject and measures the subject's breathing cycle by a change in humidity, and one of the continuous breathing cycles that indicates a breathing state at normal time. The breathing time per cycle and the change value of the output voltage corresponding to the amplitude value in normal breathing are calculated and stored as average values, and stored in the normal breathing value storage means and the normal breathing value storage means. Comparing means for comparing the breathing time and the output voltage change value with the actually measured respiratory time measured by the humidity sensor and the actually measured output voltage change value corresponding to the actual amplitude value; A state where the measured respiratory time is out of the predetermined range with respect to the respiratory time and / or the measured output voltage change value is out of the predetermined range with respect to the output voltage change value is referred to as an abnormal respiratory state of the subject. In the device with a simple configuration, and a recognition means for notifying the subject or the observer that the patient is in an abnormal breathing state when the abnormal breathing state is measured in the recognition means. Such costs can be suppressed, and an abnormal breathing state can be reliably detected. In addition, since a humidity change is detected as a change in capacitance using a humidity sensor disposed in the vicinity of the oral cavity, measurement is performed on breathing actually performed in the mouth and nose of the subject. be able to.

Hereinafter, a humidity sensor type apnea detection device according to an embodiment of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the sensor type apnea detection device 10 according to the present embodiment includes a humidity sensor 11, a sensor circuit 12, a microcomputer 13, a notification device 14, a storage unit 15, and a monitor 16.

The humidity sensor 11 is disposed in the vicinity of the oral cavity of the subject (for example, around the mouth and between the mouth and the nose), and measures the breathing cycle of the subject based on a change in humidity. The humidity sensor 11 is preferably one that detects a change in humidity as a change in capacitance. An output signal from the humidity sensor 11 is amplified by the sensor circuit 12 and output to the microcomputer 13.

The microcomputer 13 can use an arithmetic circuit of a personal computer, for example, and controls operations of the sensor circuit 12, the alarm device 14, the storage unit 15, and the monitor 16 connected thereto.

Here, the storage unit 15 is, for example, a RAM (Random Access Memory) of a personal computer, and stores a program used in the process of detecting a respiratory state, and as a normal respiratory value storage unit, Are stored as the average values of the change values of the output voltage corresponding to the breathing time per cycle of the continuous breathing cycles and the amplitude value in the breathing at the normal time, which indicate the breathing state of The calculation as the average value is performed by the microcomputer 13.

The microcomputer 13 has functions as comparison means and recognition means. As a comparison means, the normal breathing time and the output voltage change value stored in the storage unit 15, the actual breathing state measured by the humidity sensor 11, and the actual output corresponding to the actual amplitude value The voltage change value is compared. Further, as a recognition means, a state in which the measured breathing time is out of the predetermined range with respect to the breathing time and / or the measured output voltage change value is out of the predetermined range with respect to the output voltage change value. This is recognized as an abnormal respiratory state of the examiner (for example, an apnea respiratory state).

Further, the microcomputer 13 sets, as setting means, a predetermined range of the actually measured breathing time with respect to the breathing time and / or a predetermined range of the actually measured output voltage change value with respect to the output voltage change value. The predetermined range can be set to an arbitrary range according to the state of the subject and measurement conditions. For example, the predetermined range of the actually measured respiratory time with respect to the normal respiratory time is set to −30 of the normal respiratory time. The predetermined range of the actually measured output voltage change value relative to the normal output voltage change value in the range of% to + 30% may be set to the range of −30% to + 30%.

The alarm device 14 is, for example, an alarm device that emits a notification sound to notify, a lighting device that lights and notifies a notification lamp, and a vibration device that vibrates and notifies a vibrator. In the microcomputer 13 as a recognition means, When the abnormal breathing state is measured, the subject or the observer is notified of the abnormal breathing state.

The monitor 16 is a display connected to, for example, a personal computer, and displays the measurement status of the respiratory state and related information.

Subsequently, measurement of a respiratory state using the humidity sensor type apnea detection device 10 according to the present embodiment will be described.

First, the normal breathing state is measured according to the procedure shown in FIG. Data captured using the humidity sensor 11 (step S2) is amplified by the sensor circuit 12 and output to the microcomputer 13. The output is a breathing time per cycle of continuous breathing cycles indicating a normal breathing state, and a change value of the output voltage corresponding to the amplitude value in breathing during normal breathing.

In the microcomputer 13, the input value is Fourier transformed (step S3) and the average value is calculated. The coefficient A as a result of the Fourier transform is displayed on the monitor 16 (step S4).

The conversion result and the average value are stored in the storage unit 15 as a normal respiration value (step S5), and the measurement at the normal time is ended (step S6).

Next, the actual respiratory state is measured by the procedure shown in FIG.
Data captured using the humidity sensor 11 (step S12) is amplified by the sensor circuit 12 and output to the microcomputer 13. What is output is the actually measured breathing time per cycle in the continuous breathing cycle and the change value of the actually measured output voltage corresponding to the amplitude value in breathing.

In the microcomputer 13, the input value is Fourier transformed (step S13) and the average value is calculated. The coefficient B as a result of the Fourier transform is displayed on the monitor 16 (step S15).

Here, the microcomputer 13 reads the coefficient A stored in the storage unit 15 in the normal measurement, and subtracts B from A to calculate C (step S16).

Next, the microcomputer 13 compares and determines whether or not the calculated value C is out of a predetermined range (−10% to 10% in the example of FIG. 3) with respect to the normal state value A (step S17). ).

As a result of the comparison, if the calculated value C is out of the predetermined range (NO in step S17), the microcomputer 13 determines that the abnormal breathing state is present (step S18), and stores the calculated value C in the storage unit 15. Along with (Step S19), an instruction signal is output so as to give an alarm to the alarm device 14. Upon receiving this signal, the alarm device 14 issues an alarm to the subject or the observer (step S20).

On the other hand, when the calculated value C is within the predetermined range (YES in step S17), the microcomputer 13 determines that it is in a normal state (step S22). Thereafter, when measurement is continued (NO in step S23), data is taken in again (step S12). When the measurement is not continued (YES in step S23), the measurement of the actual respiratory state is ended (step S21).

It is a block diagram which shows the structure of the humidity sensor type apnea detection apparatus which concerns on embodiment of this invention. It is a flowchart which shows the process until it takes in and memorize | stores a normal respiration value. It is a flowchart which shows the process of taking in the respiratory value at the time of sleep and judging a respiratory state.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Humidity sensor type apnea detection apparatus 11 Humidity sensor 12 Sensor circuit 13 Microcomputer (comparison means, recognition means)
14 Alarm (notification means)
15 storage unit (normal breathing value storage means)
16 Monitor

Claims (8)

A humidity sensor disposed near the oral cavity of the subject, and measuring the respiratory cycle of the subject by humidity change;
The breathing time per cycle of the continuous breathing cycle indicating the breathing state at the normal time and the change value of the output voltage corresponding to the amplitude value in the breathing at the normal time are respectively calculated and stored as average values. Normal breathing value storage means;
The respiration time and the output voltage change value stored in the normal respiration value storage means, the actual respiration time measured by the humidity sensor, and the actual output voltage change value corresponding to the actual amplitude value And a comparison means for comparing
In the comparison means, the measured breathing time is out of a predetermined range with respect to the breathing time, and / or the measured output voltage change value is out of a predetermined range with respect to the output voltage change value. Recognizing means for recognizing the subject's abnormal breathing state;
In the recognition means, when the abnormal breathing state is measured, a notification means for notifying the subject or the observer that the abnormal breathing state is present;
A humidity sensor type apnea detection device comprising: 2. The humidity sensor according to claim 1, further comprising: a setting unit configured to set a predetermined range of the measured respiratory time with respect to the respiratory time and / or a predetermined range of the measured output voltage change value with respect to the output voltage change value to an arbitrary range. Type apnea detection device. The predetermined range of the actually measured breathing time with respect to the breathing time is a range of −30% to + 30% of the breathing time, and the predetermined range of the actually measured output voltage change value with respect to the output voltage change value is −30% to +30. The humidity sensor type apnea detection device according to claim 1 or 2, wherein the device is in a range of%. The humidity sensor type apnea detection device according to any one of claims 1 to 3, wherein the humidity sensor detects the humidity change as a change in capacitance. The humidity sensor type apnea detection device according to claim 1, wherein the abnormal breathing state is an apnea breathing state. The humidity sensor type apnea detection device according to any one of claims 1 to 5, wherein the notification means is an alarm device that generates a notification sound to notify. The humidity sensor type apnea detection device according to any one of claims 1 to 6, wherein the notification unit is a lighting device that turns on a notification lamp to notify. The humidity sensor type apnea detection device according to claim 1, wherein the notification unit is a vibration device that vibrates and notifies a vibrator.

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