JP2756747B2 - Biological signal detection type stimulator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an artefact detection device in a biological signal detection type electrostimulation device.

[0002]

2. Description of the Related Art A conventional electric massager, an electric stimulator, a low-frequency therapeutic device, for example, detects a diastole of the heart from biological signals such as a pulse and an electrocardiogram and applies stimulation with emphasis on the diastole. There has been proposed a device which can achieve a superior blood circulation promoting effect and / or obtain a slimming effect so as to be incomparable with the present invention.

[0003]

What is problematic in detecting a signal from a living body is how to deal with noises (artifacts) generated from sensor parts such as a pulse wave detector and electrodes, and the surroundings. Is. For example, removal by a filter is also considered, but similar to biological signals,
There is a limit to the removal of artifacts having frequency components and amplitudes.

[0004]

In view of the above, the present invention detects a plurality of signal intervals from a biological signal such as a pulse wave detected by a sensor, averages the intervals, and obtains an average value. By comparing the average value and the value obtained by subtracting the signal interval of the current signal from a threshold value derived from the average value, an apparatus for accurately detecting the occurrence of an artifact based on the threshold value is realized.

[0005]

FIG. 1 is a diagram showing an embodiment of the present invention. (1) is a sensor, which differs according to a biological signal to be measured. Examples of the sensor (1) include a photoelectric conversion transducer, an electrode, and the like. The sensor (1) is used by being attached to an earlobe, a fingertip, a chest, a limb, or the like. (2) is a biological signal recognizing means for recognizing a peak in the case of an electrocardiogram such as an R wave or a pulse wave and outputting a recognition pulse. (3) is an interval measuring means, which is a cycle of a pulse, an electrocardiogram, etc.
This is a means for measuring the interval, frequency, etc., and outputting an interval signal indicating the value. (4) is an average value calculating means, which takes in a plurality of input interval signals, averages the plurality of interval signals, and outputs an average value signal. Reference numeral (5) denotes a subtraction unit that performs a subtraction process on the interval signal output from the interval measurement unit (3) and the average signal output from the averaging unit (4) to output a subtraction value signal. (6) is a comparing means, which inputs and compares the threshold signal output from the threshold setting means (7) and the subtraction value signal output from the subtracting means, and outputs a comparison result signal. (7) is a threshold setting means, which sets an appropriate ratio and / or a fixed value to the value output from (4) and outputs a threshold signal. (8) is an output judging means. The comparison result signal output from the comparing means (6) and the recognition pulse output from the biological signal recognition means (2) are input and the comparison result signal is output. A pulse is output except when it indicates an artifact. An output means (9) outputs an stimulable electric signal to the human body in response to the output pulse of the output determination means (8). The output means (9) includes, for example, a boosting pulse generating circuit including a boosting element such as a coil and a transformer and a driver for causing the boosting operation thereof, a boosting element such as a coil and a transformer, and accumulating boosting energy. And a booster pulse generating circuit composed of a combination of a storage element such as a capacitor for driving the device and a driver for driving these elements, or a vibrator for converting a stimulation pulse into mechanical vibration. Or you may.

Next, the operation will be described. The biological signal detected by the sensor (1) is converted into a pulse by the biological signal recognition means (2) and output. The pulse output from the biological signal recognizing means (2) is input to the interval measuring means (3) and the output determining means (8), and is converted into a signal indicating a pulse interval value by the interval measuring means (3). The interval value signal output from the interval measuring means (3) is input to the averaging means (4) and the subtracting means (5). The averaging means (4) adds the inputted interval value signal together with the inputted interval value signal, averages the sum, and outputs an average signal to the subtracting means (5) and the threshold setting means (7). The subtracting means (5) causes the interval value signal output from the interval measuring means (3) to be subtracted from the average value signal output from the averaging means (4), and outputs the subtracted value to the comparing means (6). Output. The threshold setting means (7) sets an appropriate ratio and / or a fixed value to the signal of the average value calculating means (4) and outputs the threshold signal and the comparing means (6). The comparing means (6) outputs to the output determining means (8) a signal indicating the magnitude of the threshold value from the threshold signal output from the threshold setting means (7) and the subtraction value signal output from the subtracting means (5). I do. Output judgment means (8)
In response to the recognition pulse input from the biological signal recognition means (2), the comparison means (6) outputs a pulse when the signal indicating the magnitude of the input threshold is smaller than the threshold, and outputs the pulse when the signal is larger. Absent. The pulse output from the output determination means (8) is input to the output means (9), is converted into a signal for biological stimulation, and is a conductor attached to the output end (10).
The stimulus is supplied to the living body via the vibrator.

Next, another embodiment shown in FIG. 2 will be described. Sensor (21), biological signal recognition means (22), output means (2
4) is the sensor (1) shown in FIG.
(2) Since it is the same as the output means (9), the description is omitted. (23) is a one-chip microcomputer, and internal processing procedures are shown in (231) to (235). (twenty three
1) is an interval measuring means, which takes in the recognition pulse output from the biological signal recognition means (22), measures the value of the pulse interval, and outputs the measured value A. In (232), the average value calculating means takes in the measured value A obtained by the interval measuring means (231) a plurality of times, adds the values, and outputs the average value B. next
At (233), C ← AB is executed by the subtraction means, and the value of C is output. (234) is a comparison means for executing C> B / N (B / N)
Is a threshold. That is, the value C obtained by the subtraction means (233)
Is a specific ratio to the average value B obtained by the average value calculation means.
Compare whether it is larger or smaller than the value multiplied by (1 / N),
It outputs a signal that is false when large and true when small.
(235) is an output judging means, which outputs to the output means (24) in synchronization with the pulse outputted from the biological signal recognizing means (22) when an output of true is inputted from the comparing means (234). .
It is necessary to determine the plurality of additions in the above-described average value calculation means in consideration of the heart rate.
6, 8, and 16 times are preferred, but not limited thereto. Further, if the ratio (1 / N) indicated by the comparison means (234) is small, the possibility that a true pulse wave is determined as an artifact increases, and if the ratio (1 / N) is large, the artifact easily spreads.

FIG. 3 is a diagram showing the operation of the embodiment shown in FIG. (3A) is a pulse wave diagram obtained by the pulse wave sensor shown in FIG. (3B) is a diagram in which a pulse having a peak is generated from the rise of the pulse wave, and is also an example of one output pulse of the biological signal recognition means. (3C) is (3B)
FIG. 7 is an output waveform diagram when an extension period is determined from the rising edge of a pulse and a stimulation pulse is output. Examples when actual artifacts are mixed are shown in FIGS.
(3D) is a contraction of (3B) in time, and (3D)
E) is a contraction of (3C). In the section (X), a normal pulse wave is detected, and the operation is performed according to the relationship shown in (3B) and (3C). In the section (Y), an artifact in which the peak of the pulse wave frequently appears due to the swing of the sensor or the like, but the output pulse for stimulation is output while maintaining a certain section without being triggered by the artifact. Indicates that it has been done.

FIG. 4 shows still another more specific embodiment. (41) is a pulse wave sensor, which is used by being attached to an earlobe, a fingertip, or the like by a combination of an infrared LED and a phototransistor. An amplifier (42) amplifies the pulse wave electric signal detected by the pulse wave sensor.
(43) is a differentiating circuit for converting a pulse wave signal into a differential pulse wave signal. (44) is a peak hold circuit, which is means for holding the rising peak of the electric signal.
A comparator (45) compares the output of the amplifier and the output of the peak hold circuit, and outputs a pulse when one of the outputs exceeds the other input. Reference numeral (46) denotes a one-chip microcomputer, which contains a program, a program for detecting a diastole, a program for detecting an artifact shown in FIG. 2, a program for outputting a stimulation pulse, and the like. (47) is an output means, which outputs a few (HZ) stimulation pulses at several tens to several hundreds (V). Reference numeral (471) denotes a switching transistor. The base is a microcomputer (46). The emitter is grounded. The collector is connected to the anode of a diode (473) and one end of a coil (472). The other end of the coil is connected to the (+) pole of the power supply. The cathode of the diode (473) is connected to one end of the capacitor (474). Reference numeral (475) denotes a stimulus output transistor. The emitter is connected to one end of the capacitor (474), the collector is connected to the output terminal (476), and the base is connected to the microcomputer (46).

Next, the operation will be described. The pulse wave signal obtained by the pulse wave sensor (41) is amplified by an amplifier (42), and then converted into a differential waveform by a differentiating circuit (43). The differentiated wave output from the differentiating circuit (43) is converted into a peak hold circuit (49) and a comparing circuit.
It is supplied to one end of (45). The comparison circuit (45) detects the rising and falling of the output pulse of the differentiating circuit input to one input and outputs the pulse. The microcomputer (46) receives the output of the comparator (45), recognizes the diastole, and performs the artifact detection processing shown in FIGS. Before outputting the pulse for electrical stimulation, the microcomputer (46) sends several (KHz) to several tens to the transistor (471).
(KHz) pulse is output. The transistor (471)
By energizing the coil intermittently, a boost pulse is generated in the coil. Although this boost pulse has several tens to several hundreds of volts, it does not stimulate the magnetic field (μsec) and pulse width. Diode (473) coil
Conducting the boost pulse generated in (472), the capacitor (474)
A boost pulse is supplied to and accumulated. The microcomputer (46) outputs a pulse from another output terminal to the switching transistor (475) during the diastole, and causes the output terminal (476) to output a stimulus pulse. This pulse has several (Hz) to several tens (H
z) has a continuous or intermittent specification. An interface having adhesiveness and non-adhesiveness, such as a conductor and an electrode, is connected to the output end (476). This interface is mounted on the human body, abdomen, and the like.

[0011]

As described in detail above, the present invention can distinguish between an artifact and a normal wave, and has an effect that the diastole of a pulse wave can always be matched with a biological stimulus. .

[Brief description of the drawings]

FIG.

FIG. 2

FIG. 4 is a diagram showing an embodiment of the present invention.

FIG. 3 is a diagram showing the operation of the embodiment shown in FIGS. 1, 2 and 4;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 sensor 2 biological signal recognition means 3 interval measurement means 4 average value calculation means 5 subtraction means 6 comparison means 7 threshold value setting means 8 output judgment means 9 output means

Claims (1)

(57) [Claims] A biological signal detection sensor for obtaining a biological signal based on a heartbeat ; pulse output means for outputting a recognition pulse from a biological signal obtained from the biological signal detection sensor; An interval measuring means for measuring a pulse interval of the pulse, an average value measuring means for measuring an average value from a plurality of interval values obtained by the interval measuring means, an average value obtained by the average value measuring means and the interval measurement Subtracting means for outputting a difference value from the pulse interval value obtained by the means; comparing the difference value output from the subtracting means with a threshold obtained by multiplying the average value by a specific ratio; When the value of is less than the threshold,
Determine the diastolic interval of the heart based on the recognition pulse output by the pulse output means as the pulse true,
A stimulus is generated during the diastolic interval based on the heart beat.
A biological signal detection type stimulating device comprising stimulus output means for outputting a body signal to a person who has detected the body signal .