JP2018139759A - Biological signal measuring device - Google Patents

Abstract

A battery built in a biological signal measuring instrument (wearable biological sensor) is reduced as much as possible. A pair of electrodes 10a and 10b that come into contact with a living body at the time of measuring a biological signal, a biological signal processing circuit 100 that performs predetermined processing on a biological signal detected by the electrodes, and power to the biological signal processing circuit 100 are supplied. The biological signal measuring instrument 1 including the battery 210 includes a power activation switch 110 that turns on and off the power supplied from the battery 210 to the biological signal processing circuit 100, and a control unit that controls the power activation switch 110. The control unit monitors the interelectrode resistance existing between the electrodes 10a and 10b. When the interelectrode resistance exceeds a predetermined threshold value, the control unit 110 turns off the power activation switch 110, and when the interelectrode resistance is equal to or lower than the threshold value, The power activation switch 110 is turned on to supply power from the battery 210 to the biological signal processing circuit 100. [Selection] Figure 11

Description

  The present invention relates to a biological signal measuring apparatus, and more specifically, a biological signal measuring instrument (wearable biological sensor) used by being attached to a living body (human body) like a bandage and a power supply for charging a built-in battery thereof. The present invention relates to a signal measuring device.

  In addition to the biological signal measurement processing unit that measures and processes electrocardiogram signals, myoelectric signals, electroencephalogram signals, etc., the wearable biological signal measuring instrument has an internal power supply that supplies power to the biological signal measurement processing unit. Built-in battery.

  Usually, a secondary battery such as a lithium ion battery is used as the battery. Therefore, an SD terminal for charging the secondary battery and a dedicated charging terminal are provided. The terminal is connected to the charging terminal for charging (for example, see Patent Document 1).

  However, in order to provide a durable charging terminal on a small circuit board manufactured for wearable use, it is necessary to increase the strength of the circuit board, which may hinder downsizing, weight reduction, thickness reduction, or flexibility. It has become.

  In addition, operating power (drive power) is supplied from the secondary battery to the biological signal measurement processing unit, etc., but the biological signal measuring instrument is actually attached to the human body to minimize the consumption of the secondary battery. In addition, it is preferable to supply the operation power to the biological signal measurement processing unit or the like.

Japanese Patent Laying-Open No. 2015-163225

  Accordingly, an object of the present invention is to reduce the consumption of a battery built in a biological signal measuring instrument (wearable biological sensor) as much as possible. Another object of the present invention is to improve waterproofness by eliminating a mechanical power switch.

In order to solve the above problems, the present invention includes a biological signal measuring instrument used by being attached to a living body,
The biological signal measuring instrument supplies a power to the biological signal processing circuit, a pair of electrodes that are in contact with the living body at the time of measuring the biological signal, a biological signal processing circuit that processes a biological signal detected by the electrodes, and the biological signal processing circuit. A biological signal measuring device comprising a battery, comprising: a power activation switch that turns on and off power supplied from the battery to the biological signal processing circuit; and a control unit that controls the power activation switch. Monitors the interelectrode resistance existing between the electrodes, turns off the power supply start switch when the interelectrode resistance exceeds a predetermined threshold value, and turns off the power supply start switch when the interelectrode resistance is less than the threshold value The power is supplied from the battery to the biological signal processing circuit.

  As a preferred embodiment, the control unit has a two-input type comparator, the power supply voltage in the device is V0, and one input terminal of the comparator has a resistor R1, connected between the power supply in the device and the ground. A voltage V1 (= R2 / (R1 + R2)) obtained by dividing the power supply voltage V0 by a voltage dividing circuit including R2 is applied, and the other input terminal of the comparator has the one electrode and the in-device power supply. A voltage V2 obtained by dividing the power supply voltage V0 by a voltage dividing circuit including a resistor R3 connected between the resistor R4, a resistor R4 connected between the other electrode and grunge, and the interelectrode resistor R5 ( = R4 / (R3 + R4 + R5)) is applied, the resistors R2, R3, and R4 have the same resistance value Ra, the resistor R1 has a resistance value Rb that is higher than the resistance value Ra, and the threshold value is defined as Rb-Ra. It is.

  In the present invention, the resistors R1 to R4 are preferably high resistance elements having a current consumption of 1 μA or less.

  According to the present invention, the power activation switch is on and power is supplied from the battery to the biological signal processing circuit only when the biological signal measuring instrument (wearable biological sensor) is attached to the human body. Since the switch is off, battery consumption can be reduced as much as possible. Further, the power switch includes a comparator and a resistance element, and since there is no mechanical power switch, waterproofness can be improved.

The schematic diagram which shows 1st Embodiment of the biosignal measuring device by this invention. The schematic diagram which shows the 1st Example of the biosignal / feeding power distribution means with which the said 1st Embodiment is provided. The schematic diagram which shows the 2nd Example of the said biosignal / feed electric power distribution means. The circuit diagram which shows two specific examples of the nonlinear circuit in the said 2nd Example. The schematic diagram which shows the 3rd Example of the said biosignal / feed electric power distribution means. The schematic diagram which shows the 4th Example of the said biosignal / feed electric power distribution means. The circuit diagram which shows the three specific examples of the switching circuit in the said 4th Example. The schematic diagram which shows 5th Example of the said biosignal / feed electric power distribution means. FIG. 10 is a circuit diagram showing three specific examples of the switching circuit in the fifth embodiment. The schematic diagram which shows the structure of the electric power feeder contained in the biological signal measuring device by this invention. The schematic diagram which shows 2nd Embodiment of the biosignal measuring device by this invention. The schematic diagram which shows 3rd Embodiment of the biosignal measuring device by this invention. The schematic diagram which shows the procedure of the determination performed in the said 3rd Embodiment. The schematic diagram which shows 4th Embodiment of the biosignal measuring device by this invention. The schematic diagram which shows 5th Embodiment of the biosignal measuring device by this invention. The schematic diagram which shows an example of the data transferred in the said 5th Embodiment. (A) Front view of component mounting side of biological signal measuring instrument, (b) Rear view of electrode side, (c) Side view. The schematic diagram for demonstrating the board | substrate connection structure of the said biosignal measuring device. (A) Front view of component mounting side, (b) Rear view of electrode side, and (c) (B) cross-sectional view taken along line AA. The (a) front view and (b) back view which show another example of the said waterproof cover. The schematic diagram which shows the relationship between the said biosignal measuring device, the adhesive tape for mounting | wearing, and a power feeder. The side view which isolate | separates and shows the said biosignal measuring device and the said adhesive tape for mounting | wearing. The schematic diagram which shows an example of the use condition of the biosignal measuring device of this invention. The schematic diagram which shows the connection state via the communication line with the said biosignal measuring device and external apparatuses, such as a server.

  Next, some embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto.

  As shown in FIG. 1, the biological signal measuring apparatus according to this embodiment (first embodiment) is built in a biological signal measuring instrument 1 as a wearable biological sensor (sensor chip) and the biological signal measuring instrument 1. And a power feeder (charger) 2 that feeds charging power to the secondary battery 210.

  The biological signal measuring instrument 1 basically includes a pair of electrodes 10a and 10b, a biological signal processing circuit 100, a secondary battery 210 as an internal power source, and a charging circuit 200 for charging the secondary battery 210. And a biosignal / feeding power distribution means 300. The biological signal processing circuit 100 and the charging circuit 200 are connected to the electrodes 10a and 10b through the biological signal / feed power distribution means 300 so as to be switchable.

  The electrodes 10a and 10b are in contact with the living body (human body) H at the time of measuring a biological signal, and are in contact with the power supply terminals 20a and 20b of the power feeder 2 at the time of charging. That is, in the present invention, the electrodes 10a and 10b are used both as a biological signal detection terminal and a charging terminal, and do not have a dedicated charging terminal.

  In addition, when it is not necessary to distinguish the electrodes 10a and 10b, the electrodes 10 are collectively referred to. Similarly, when it is not necessary to distinguish between the power supply terminals 20a and 20b, the power supply terminals 20 are collectively called. The electrode 10 may be three or more electrodes.

  The biological signal processing circuit 100 processes potentials and currents such as cardiac potential, myoelectric potential, brain waves, and skin resistance as biological data detected by the electrode 10. As the biological signal processing circuit 100, a differential amplifier, an A / D converter, an MCU, a memory, or the like can be used. For the purpose of measuring skin resistance, a voltage generator or a current generator that allows current to flow through the electrode H through the electrode 10 may be used.

  The charging circuit 200 charges a secondary battery 210 (sometimes simply referred to as “battery”) such as a lithium ion battery mounted on the biological signal measuring instrument 1. The battery 210 supplies power to each part of the biological signal measuring instrument 1.

  The biological signal / feeding power distribution unit 300 guides the biological signal to the biological signal processing circuit 100 when the biological signal is measured, and guides the feeding power from the power feeder 2 to the charging circuit 200 when charging. The biological signal / feed power distribution means 300 has several configuration examples.

  First, in the first embodiment shown in FIG. 2, a signal transmission circuit 310 and a power transmission circuit 320 are used for the biological signal / feed power distribution means 300.

  The signal transmission circuit 310 is connected between the electrode 10 and the biological signal processing circuit 100, guides the biological signal to the biological signal processing circuit 100 when measuring the biological signal, and supplies power to the biological signal processing circuit when charging the battery. Prevent inflow.

  The power transmission circuit 320 is connected between the electrode 10 and the charging circuit 200, guides the feeding power to the charging circuit 200 when the battery is charged, and prevents the biological signal from flowing into the charging circuit 200 when measuring the biological signal.

  As a second embodiment of the biological signal / feeding power distribution unit 300, in the case of DC feeding, a DC cut filter 311 is used in the signal transmission circuit 310 as shown in FIG. The DC cut filter 311 allows a biological signal (alternating current) to pass therethrough and prevents the passage of DC power. The DC cut filter 311 may be a capacitor.

  In the case of DC power feeding, a non-linear circuit 321 is preferably employed for the power transfer circuit 320 as shown in FIG. The nonlinear circuit 321 has a low impedance when the power supply voltage is high, and has a high impedance when the supply voltage is low, such as a biological voltage, and functions as the power transmission circuit 320.

  The non-linear circuit 321 includes a non-linear circuit 322 having a bridge connection of four diodes D1 to D4 and a capacitor C shown in FIG. 4A, and transistors as four semiconductor switches shown in FIG. Then, a non-linear circuit 323 having a bridge connection of FETs Tr1 to Tr4 and a capacitor C can be exemplified.

  The non-linear circuits 322 and 323 may be configured by two non-linear elements, but by forming a bridge with four non-linear elements to form a full-wave rectifier circuit, for example, the power supply terminal 20a has a positive pole and the power supply terminal 20b has a negative polarity. Assuming that it is a pole, the + feeding terminal 20a is connected to the electrode 10a, the -feeding terminal 20b is connected to the electrode 10b, and conversely, the -feeding terminal 20b is connected to the electrode 10a and the + feeding terminal is connected to the electrode 10b. Even if 20a is connected, it operates normally.

  When the diode D is used as shown in FIG. 4A, the rising voltage of the diode D is 0.5 to 0.7 V, so that the diode D is not turned on for a normal biological signal. Therefore, the biological signal does not flow into the charging circuit 200.

  In addition, when a transistor (FET) Tr is used as shown in FIG. 4B, the transistor Tr can further increase the turn-on voltage or reduce the leakage current depending on the threshold value.

  Although the voltage used for DC power supply is, for example, 6 to 8 V, the output voltage of the nonlinear circuits 322 and 323 is, for example, 4.5 to 4, although it varies depending on the on-resistance of the diode D and the transistor Tr of the nonlinear element and the flowing current. It becomes about 6.5V.

  Next, as a third embodiment of the biological signal / feeding power distribution unit 300, in the case of AC feeding, a low-pass filter 312 is used for the signal transmission circuit 310 and a high-pass for the power transmission circuit 320 as shown in FIG. A filter 324 and a rectifier circuit 325 are used.

  The low-pass filter 312 allows the biological signal to pass therethrough, but the AC feeding power blocks the passage. On the other hand, the high-pass filter 324 allows the AC power supply to pass, but prevents the biological signal from passing therethrough.

  It is preferable to employ a differential configuration (balance drive) as the AC power supply. The reason is that if a single-ended configuration (unbalanced drive) is used for the two electrodes 10a and 10b having high impedance, the GND (ground) potential of the biological signal measuring instrument 1 becomes unstable and touches GND. This is because the output voltage of the rectifier circuit 325 may change.

  The frequency component of the biological signal exists around 0.01 Hz to several kHz. By setting the frequency used for the AC power supply to 13.56 MHz (Industry-Science-Medical band), for example, it can be separated from the biological signal by about 4 digits, and the low-pass filter 312 can be used effectively.

  Further, by setting the cut-off frequency of the low-pass filter 312 to several kHz to several tens of kHz, the feed power can be attenuated by about −40 dB even in the primary filter, so that sufficient blocking performance of the feed power can be obtained.

  Note that the rectifier circuit 325 may use the nonlinear circuits 322 and 323 shown in FIGS.

  As a fourth embodiment of the biosignal / feed power distribution means 300, a switching circuit 326 can be used for the power transmission circuit 320 as shown in FIG. Here, the switching circuit 326 is a switch circuit that is driven on and off by the switching control means 327, and examples thereof include the switches shown in FIGS.

  The switch in FIG. 7A is a reed switch 326a. In this case, a permanent magnet 327a is provided as the switching control means 327 on the power feeder 2 side, and the reed switch 326a is turned on by the permanent magnet 327a during power feeding (charging), so that the charging circuit 200 is charged from the power feeder 2 When the electric power is supplied and the permanent magnet 327a is separated in distance when the biological signal is measured, the reed switch 326a is turned off.

  The switch shown in FIG. 7B includes a transistor (FET in this example) 326b as a semiconductor switch, and is turned on / off according to the voltage between the electrodes 10a and 10b. As the switching control means 327, an A / D converter (comparator) 327b that detects a voltage between the electrodes 10a and 10b is used.

  According to this, the power feeder 2 is connected to the electrodes 10a and 10b for charging. For example, when the voltage between the electrodes 10a and 10b is 5 V or more, the transistor 326b is turned on. It is off during biometric measurement.

  The switch in FIG. 7C is also composed of a transistor (FET) 326c as a semiconductor switch, like the switch in FIG. 7B. In this case, the switch is turned on and off according to the impedance between the electrodes 10a and 10b.

  The switching control means 327 includes a signal generator 327c that supplies a measurement signal having a predetermined frequency between the electrodes 10a and 10b, and an A / D converter (comparator) that detects an impedance between the electrodes 10a and 10b when the measurement signal is applied. 327d is used.

  According to this, the power feeder 2 is connected for charging, and the transistor 326c is turned on when the impedance between the electrodes 10a and 10b becomes, for example, 100Ω or less. Incidentally, when measuring a biological signal, the impedance between the electrodes 10a and 10b shows a value of 10 kΩ or more, for example.

  As shown in FIG. 8, a switching circuit 330 may be used as a fifth embodiment of the biological signal / feed power distribution unit 300. According to the switching circuit 330, the electrode 10 is selectively connected to either the biological signal processing circuit 100 or the charging circuit 200. Three examples are shown in FIGS.

  In the example of FIG. 9A, two reed switches 330a and 330b are used. Each is a two-contact switching type that includes a first contact a and a second contact b that are selectively connected to the common terminal c via a lead piece.

  In the reed switches 330a and 330b, the common terminals c are connected to the electrodes 10a and 10b, the first contact a is connected to the biological signal processing circuit 100, and the second contact b is connected to the charging circuit 200. As the switching control means 327, a permanent magnet 327a provided on the feeder 2 side is used as described with reference to FIG.

  According to this, at the time of power feeding (charging), the reed switches 330a and 330b are both switched to the second contact b side by the permanent magnet 327a and charging power is supplied from the power feeder 2 to the charging circuit 200.

  On the other hand, when measuring the biological signal, the permanent magnets 327a are separated from each other, whereby both the reed switches 330a and 330b are switched to the first contact a side, and the electrodes 10a and 10b are connected to the biological signal processing circuit 100. Is done.

  In the example of FIG. 9B, four transistors (FETs in this example) Tr1 to Tr4 are used as semiconductor switches.

  For example, the sources of the first transistor Tr1 and the second transistor Tr2 are both connected to one electrode 10a side, and the drain of the first transistor Tr1 is connected to the biological signal processing circuit 100, whereas the second transistor The drain of Tr2 is connected to the charging circuit 200.

  For example, the sources of the third transistor Tr3 and the fourth transistor Tr4 are both connected to the other electrode 10b side, and the drain of the third transistor Tr3 is connected to the biological signal processing circuit 100, whereas the fourth transistor The drain of Tr4 is connected to the charging circuit 200.

  As the switching control means 327, an A / D converter (comparator) 327b that detects the voltage between the electrodes 10a and 10b may be used as described with reference to FIG.

  According to this, when the power feeder 2 is connected for charging, for example, when the voltage between the electrodes 10a and 10b becomes 5 V or more, the A / D converter 327b supplies a predetermined voltage to the gates of the second transistor Tr2 and the fourth transistor Tr4. A control voltage is applied, whereby the second transistor Tr2 and the fourth transistor Tr4 become conductive (at this time, the first transistor Tr2 and the third transistor Tr4 are both nonconductive), and the charging circuit 200 is connected to the electrode 10. .

  On the other hand, when measuring a biological signal, the voltage between the electrodes 10a and 10b is less than 5V, so that a predetermined control voltage is applied from the A / D converter 327b to the gates of the first transistor Tr2 and the third transistor Tr4. As a result, the first transistor Tr1 and the third transistor Tr3 become conductive (at this time, the second transistor Tr2 and the fourth transistor Tr4 are both nonconductive), and the biological signal processing circuit 100 is connected to the electrode 10.

  In the example of FIG. 9C, as in the example of FIG. 9B, four transistors (FETs) Tr1 to Tr4 are used as semiconductor switches. Further, the switching control means 327 has a signal generator 327c for supplying a measurement signal of a predetermined frequency between the electrodes 10a and 10b and an impedance between the electrodes 10a and 10b, similarly to the switching control means in FIG. An A / D converter (comparator) 327d is used.

  According to this, when the power feeder 2 is connected for charging and the impedance between the electrodes 10a and 10b becomes 100Ω or less, for example, the A / D converter 327d applies a predetermined amount to the gates of the second transistor Tr2 and the fourth transistor Tr4. A control voltage is applied, whereby the second transistor Tr2 and the fourth transistor Tr4 are turned on (at this time, both the first transistor Tr1 and the third transistor Tr3 are turned off), and the charging circuit 200 is connected to the electrode 10. .

  On the other hand, when measuring a biological signal, the impedance between the electrodes 10a and 10b is, for example, 10 kΩ or more, so that a predetermined control voltage is applied to the gates of the first transistor Tr1 and the third transistor Tr3 from the A / D converter 327d. As a result, the first transistor Tr1 and the third transistor Tr3 become conductive (at this time, the second transistor Tr2 and the fourth transistor Tr4 are both nonconductive), and the biological signal processing circuit 100 is connected to the electrode 10. Become.

  Next, the power feeder 2 will be described with reference to FIG. In addition to the voltage converter 21, the charging end determination circuit 22, and the overcurrent protection circuit 23, the power feeder 2 includes a communication unit 24, an MPU (microprocessor unit) 25 as a control unit, and a memory 26. .

  The voltage converter 21 may be a DC-DC converter or a DC-AC converter, and converts, for example, a USB DC voltage (5 V) into a DC or AC voltage. In the case of AC power supply, for example, a differential voltage of about 13.56 MHz and one side of about 7 to 10 Vp-p is output. In the case of DC power supply, for example, a voltage of 6 to 8V is output.

  The charge end determination circuit 22 determines the end of charge from the attenuation state of the power supply at the power supply terminals 20a and 20b. By determining the end of charging from the current flowing through the power supply terminals 20a and 20b, it is possible to cope with a decrease in the determination current.

  When, for example, a capacity of 10 mAh is used as the secondary battery 210 mounted on the biological signal measuring instrument 1, the charging current before the end of charging is about 1 mA. The current value used for determining the end of charging is smaller than this value, but can be detected by using a resistor or a current transformer.

  The overcurrent protection circuit 23 operates when the power supply terminals 20a and 20b are short-circuited for some reason, for example, and turns off a power supply switch (not shown) in the voltage converter 21.

  Further, as will be described later, the communication unit 24 performs a biological signal measurement of a function of transmitting biological data stored in the biological signal measuring instrument 1 to an external device (for example, a cloud server) and a command from the external device. A function of transmitting to the container 1.

  The MPU 25 performs advanced processing that cannot be performed by the MCU 121 (see FIG. 14) in the biological signal measuring instrument 1 that has power supply restrictions. For example, encryption processing or anonymization processing is performed so that an individual cannot be specified from the viewpoint of personal information protection. The memory 26 temporarily stores past data accumulation, case data on the cloud, and the like.

  Next, a second embodiment of the biological signal measuring device will be described with reference to FIG. In the second embodiment, the biological signal measuring instrument 1 includes an automatic power switch 110 that detects a living body and automatically turns on (starts up) the power in the biological signal processing circuit 100.

  The automatic power switch 110 has a two-input type comparator 111, and one end of each of the resistors R1 and R2 is connected in parallel to one input terminal In1 of the comparator 111. The other end of the resistor R1 is connected to the in-device power supply V0, and the other end of the resistor R2 is connected to the ground.

  The other input terminal In2 of the comparator 111 is connected to the signal line Lb of the electrode 10b, and a resistor R4 is connected between the other input terminal In2 and the ground. A resistor R3 is connected between the signal line La of the electrode 10a and the in-device power supply V0.

The resistance between the electrodes 10a and 10b is R5, the voltage applied to one input terminal In1 is V1, the voltage applied to the other input terminal In2 is V2, and V1 and V2 are
V1 = V0 × R2 / (R1 + R2)
V2 = V0 × R4 / (R3 + R4 + R5)
It is represented by

  The comparator 111 compares V1 and V2, and instructs the power activation IC 112 to activate when V2> V1. For example, if R2, R3, and R4 are 10 MΩ and R1 is 11 MΩ, V2> V1 when the resistance value of the resistor R5 is 1 MΩ or less, and the power activation IC 112 is instructed to be activated as it is in contact with the living body. Turn on the power automatically.

  The automatic power switch 110 is preferably disconnected from the power supply after the power is turned on. However, if R1 to R4 are made high resistance as described above, the power consumption is consumed even if the automatic power switch 110 is not disconnected from the power supply after the power is turned on. Can be minimized.

  In this example, R1 to R4 are set to high resistances as described above, and the current consumption flowing through the comparator 111 and the resistors R1 to R4 is set to 1 μA, so that the distance between the electrodes is constantly monitored. As an example, since a half-life with a current of 1 μA is about 6 months in a 10 mAh battery, it does not affect the use for several days when taking biometric data.

  Note that it is preferable to stop the function of the automatic power switch after the power is turned on. The reason is that the DC current flowing through the electrodes 10a and 10b may become noise for biosignal detection.

  Next, a third embodiment of the biological signal measuring device will be described with reference to FIG. In the third embodiment, the biological signal measuring instrument 1 has a wearing state check function.

  In the biological signal processing circuit 100 of the biological signal measuring instrument 1, in addition to the automatic power switch function described in FIG. 11, the skin resistance measurement / processing unit, the electrocardiographic signal measurement / processing are provided as the original measurement / processing functions. A unit, a myoelectric signal measurement / processing unit, an electroencephalogram signal measurement / processing unit, an environmental physical quantity measurement / processing unit, and the like. From these various data, whether the biological signal measuring instrument 1 is correctly mounted on a living body is mounted. Check status.

  As a determination method (algorithm), it is expected to determine whether it is within the range of the expected signal level, match comparison with an expected waveform template such as an electrocardiogram waveform (matched filter), and perform frequency analysis. A quantitative comparison with the frequency distribution, determination based on an expected signal-to-noise ratio (S / N ratio), and the like can be used.

  As an example, FIGS. 13 (a) and 13 (b) show a procedure for determining the wearing state by matching comparison of electrocardiographic waveforms.

  Taking an electrocardiogram waveform as an example, first, as shown in (b-1) of FIG. 13B, threshold values r1, r2, R, P, T, Q, and S waves are set to threshold values r1, r2, and r3 (r3 <r2 <r1) is set, r1 is greater than or equal to r1 (r1 ≦ R wave), and P and T waves are greater than or equal to r2 and less than r1 (r2 ≦ P wave, T wave <r1), Q wave , S wave is less than r3 (Q wave, S wave <r3).

  Referring to FIG. 13A, when performing a logical determination on this threshold value, unnecessary signal components are removed from the raw signal by a bandpass filter. In that case, you may use a differential signal as needed. The logic determination can be performed by a comparator (either digital or analog is possible). FIG. 13 (b) (b-2) shows the result of the logical determination with respect to the threshold, but it may be normalized with the maximum peak (R wave in this example).

  Next, with respect to the expected logic prepared in advance (a template serving as a criterion, see (b-3) in FIG. 13B) and the threshold values shown in (b-2) in FIG. 13B. Take logical product with logical judgment. An example of the result is shown in (b-4) of FIG.

  Then, in order to avoid the influence of noise or the like, the logical product is integrated for a certain period, and the threshold value of the integration result is determined as a matching determination. As a result, as shown in (b-5) of FIG. 13B, for example, if the integration result at time t0 exceeds the comprehensive determination threshold, it is determined that the expected electrocardiographic waveform has been detected, that is, the living body. It is determined that the signal measuring instrument 1 is correctly attached to the living body H. Otherwise, the alarm means 113 such as an LED, vibrator, buzzer or the like is operated to notify the wearer that the wearing is abnormal.

  Next, a fourth embodiment of the biological signal measuring device will be described with reference to FIG. In the fourth embodiment, the biological signal measuring instrument 1 has a communication function with the power feeder 2.

  In order to communicate with the power feeder 2, an MCU (microcontroller unit) 121, a memory 122, an I / O interface 123, and an ADC (analog-digital conversion circuit) 124 are included in the biological signal processing circuit 100 of the biological signal measuring instrument 1. Etc. are provided.

  The MCU 121 stores the result of processing the biological signal in the memory 122 and controls communication with the power feeder 2. As an example of the biological signal processing, heart rate fluctuation is obtained from an electrocardiogram waveform, and a movement distance and a momentum are obtained from acceleration.

  The memory 122 includes a RAM (Random Access Memory) and a ROM (Read Only Memory), the biological signal data processed by the MCU 121 is stored in the RAM, and a processing program is written in the ROM.

  The I / O interface 123 generates a signal for sending data to the power feeder 2. Further, the ADC 124 receives data, a measurement program, and the like from the power feeder 2 and performs firmware replacement.

  As another embodiment of the communication function with the power feeder 2 (fifth embodiment of the present invention), as shown in FIG. 15, a wakeup circuit 131 as a connection detecting means, a modulation switch (SW) 132 is provided. A mode including ADC 133, error correction decoding circuit 134a, error correction encoding circuit 134b, and communication control unit 135 is also included in the present invention.

  The Wakeup circuit 131 detects the power supply power (charging power), thereby determining that this device (biological signal measuring device 1) is set in the power supply device 2, and sets the communication function to the operating state.

  The modulation switch 132 changes the impedance between the differentials in order to modulate the feed power. An external transistor having a high withstand voltage can be placed.

  The ADC (which may be a comparator) 133 converts the modulation of the feeding power into binary or multi-value. A protective resistor and a protective diode can be placed as required.

  The error correction decoding circuit 134a and the error correction encoding circuit 134b reduce the influence of transmission path distortion by Reed-Solomon, Viterbi, Turbo, LDPC, or the like. The communication control unit 135 generates transmission / reception timings and controls each unit.

  FIG. 16 shows an example of data transferred by the communication circuit between the biological signal measuring instrument 1 and the power feeder 2, which will be described.

  The heart rate fluctuation is obtained from the electrocardiogram waveform by the floating unit of the MCU 121 or a dedicated HW (hardware), and the heart rate fluctuation is frequency-decomposed into, for example, 16 gradations through a variable band limiting filter. For this purpose, it is preferable to decompose the band of the IIR band limiting filter (BPF) by gradually changing the band.

  Record every certain time, for example, once every 10 seconds. The amount of information is 24 hours (86400 seconds), which is 16 frequencies × 16 gradations (8 bits) × 8640 = about 8.6 kB.

  Similarly, the information amount for 24 hours when the acceleration is frequency-decomposed is about 10 kB, and the information amount for 24 hours of the movement distance obtained by integrating the acceleration is about 10 kB.

  According to the present invention, the power feeder 2 is also called a docking station, and the information (biological data and the like) stored in the memory 122 is passed through the power feeder 2 while charging the biological signal measuring instrument 1 connected to the power feeder 2. For example, it can be transmitted to a cloud server or the like.

  Next, an example of a product form (sensor chip) provided to the market of the biological signal measuring instrument 1 will be described with reference to FIG.

  The sensor chip 1 includes first and second substrates 30 and 40 and a low bending rigidity portion 50 that connects the substrates 30 and 40.

  A hard substrate such as a copper-clad laminate is used for the substrates 30 and 40, and a flexible wiring board is preferably used for the low bending rigidity portion 50. Hereinafter, the low bending rigidity portion 50 may be referred to as a flexible wiring board.

  One side (front side) of the substrates 30 and 40 shown in FIG. 17A is the component mounting surfaces 30a and 40a. In this example, the biological signal processing circuit 100 is provided on the component mounting surface 30a of the first substrate 30. The charging circuit 200 is mounted on the component mounting surface 40a of the second substrate 40, and the secondary battery 210 as a power source is mounted. Since the secondary battery 210 is heavier than other components, the secondary battery 210 is preferably arranged on the connecting portion side. The biological signal / feed power distribution unit 300 may be provided on either the first substrate 30 or the second substrate 40.

  The other surfaces of the substrates 30 and 40 shown in FIG. 17B are the back surfaces 30b and 40b, and one electrode 10a is provided on the back surface 30b of the first substrate 30. The other electrode 10b is provided on the back surface 40b. As described above, the electrodes 10 a and 10 b are connected to the biological signal processing circuit 100 and the charging circuit 200 via the biological signal / feed power distribution unit 300.

  The length L of the flexible wiring board 50 is preferably as long as possible in order to reduce the force with which the electrodes 10a and 10b are to peel off from the skin. Each side of the substrates 30 and 40 is 30 mm or less, preferably 20 mm or less.

  Also, referring to FIG. 17C, the thickness including the electrode 10, the substrates 30, 40, the biological signal processing circuit 100, the charging circuit 200, the battery 210, and other members is 10 mm or less, preferably 5 mm or less. To do.

  This is because the height from the skin is lowered to reduce the force (bending moment) to be peeled off. In addition, the board | substrates 30 and 40 do not necessarily need to be a rectangle, and there may be a curved part.

  Referring to FIG. 18, substrates 30 and 40 are formed of a multilayer build-up substrate including an inner layer circuit, and flexible wiring board 50 is sandwiched between predetermined inner layers at the time of build-up. It is preferable to form the through via 51 in the vicinity of the opposing end portions on the connection side of 30 and 40. The through via 51 may be filled with plating, resist, or the like.

  As for the arrangement of the mounted components, as shown in FIG. 18B, the biological signal processing circuit 100 and the battery 210 are arranged on the first substrate 30 side, and the charging circuit 200 is arranged on the second substrate 40 side. However, preferably, as shown in FIG. 18A, the biological signal processing circuit 100 is disposed on one first substrate 30 side, and the charging circuit 200 and the battery 210 are disposed on the other second substrate 40 side. It is good to arrange.

  That is, according to the arrangement shown in FIG. 18A, the first substrate 30 side is combined with the wiring related to the biological signal processing, and the second substrate 40 side is combined with the power supply system wiring. The pattern may be a minimum of power supply wiring and control wiring, and the flexible wiring board 50 can be made more flexible.

  Further, since the biological signal processing circuit 100 usually has a larger circuit area than the charging circuit 200, the first substrate 30 and the second substrate 40 are approximately equal in area when the arrangement shown in FIG. Can be the same size.

  As a result, the flexible wiring board 50 is disposed substantially at the center in the length direction of the sensor chip 1 (left and right direction in FIG. 18), and the lengths of both the substrates 30 and 40 can be increased. Can be made difficult to peel off from the skin.

  FIG. 19 shows the waterproof cover 60 of the sensor chip 1. 4A is a front view of a waterproof cover 60 that covers the component mounting surfaces 30a and 40a of the sensor chip 1, and FIG. 4B is a rear view of the waterproof cover 60 that covers the back surfaces 30b and 40b of the sensor chip 1. FIG. 4C is a cross-sectional view taken along line AA in FIG.

  The waterproof cover 60 is made of a low-rigidity material, preferably silicon rubber, and is formed in a bag shape that houses the sensor chip 1 shown in FIG. As shown in FIG. 19B, openings 61a and 61b for exposing the electrodes 10a and 10b are provided on the back side.

  As another example of the waterproof cover 60, as shown in FIG. 20, the waterproof cover 60 includes two members, a first waterproof cover 60a that covers the first substrate 30 and a second waterproof cover 60b that covers the second substrate 40. The first board 30 and the second board 40 are individually waterproofed.

  As shown in FIG. 20B, an opening 61a for exposing the electrode 10a is provided on the back side of the first waterproof cover 60a, and the electrode 10b is provided on the back side of the second waterproof cover 60b. Is provided with an opening 61b.

  According to this, since the portion of the flexible wiring board 50 is not covered with the waterproof cover, the original flexibility of the flexible wiring board 50 is not impaired.

  The sensor chip 1 may be directly attached to the skin of a living body, but preferably a mounting adhesive tape 70 shown in FIGS. 21 (a) and 21 (b) is used. FIG. 21C is a schematic diagram illustrating the electrode surface side of the sensor chip 1, and FIG. 21D is a schematic diagram illustrating the power supply terminal side of the power feeder 2.

  The mounting adhesive tape 70 includes skin-side electrodes 71a and 71b made of a biocompatible gel or the like at two places on the left and right sides of the skin sticking surface side (paste surface side) in FIG. Although not shown, the skin-side electrodes 71a and 71b are covered with release paper when not in use.

  On the surface side (front surface side) shown in FIG. 21B of the mounting adhesive tape 70, connection electrodes 72a and 72b are provided corresponding to the skin side electrodes 71a and 71b. The connection electrodes 72a and 72b are made of a magnetic material such as iron, and are arranged at equal intervals with the electrodes 10a and 10b of the sensor chip 1. The power supply terminals 20a and 20b of the power supply 2 are also made of a magnetic material such as iron, and are arranged at equal intervals with the electrodes 10a and 10b of the sensor chip 1.

  On the other hand, the electrodes 10a and 10b of the sensor chip 1 are made of a permanent magnet material, and the sensor chip 1 is selectively held by the mounting adhesive tape 70 and the power feeder 2 by its magnetic attraction force. FIG. 22 shows how the sensor chip 1 is attached to the mounting adhesive tape 70.

  Next, an example of a procedure for using the sensor chip 1 will be described with reference to FIGS. First, (a) the release paper is peeled off from the mounting adhesive tape 70 to expose the skin-side electrodes 71a and 71b, and (b) the mounting adhesive tape 70 is attached to a predetermined part of a living body (human body), for example, the chest.

  Next, (c) the charged sensor chip 1 is attached to the mounting adhesive tape 70 as shown in FIG. At this time, the sensor chip 1 is held by the mounting adhesive tape 70 when the electrodes 10a and 10b are magnetically attracted to the connection electrodes 72a and 72b. The sensor chip 1 may be attached to a plurality of locations on the living body.

  (D) For example, when biometric data is acquired and stored in the memory 122 for several hours to several days, the sensor chip 1 is removed from the mounting adhesive tape 70 and (e) the sensor chip 1 is set in the power feeder 2. Also at this time, the sensor chip 1 is securely held by the power feeder 2 because the electrodes 10a and 10b are magnetically attracted to the power feeding terminals 20a and 20b.

  When the sensor chip 1 is set in the power feeder 2, the battery 210 of the sensor chip 1 is charged from the power feeder 2. In parallel with this, the battery is stored in the memory 122 of the biological signal processing circuit 100. Living body data is transferred to the memory 26 of the power feeder 2.

  This transfer of biometric data is performed according to an instruction from the MPU 25 of the power feeder 2 and / or the MCU 121 of the sensor chip 1. In this embodiment, the power feeder 2 includes a charging lamp 2a and a communication lamp 2b. The charging lamp 2a is turned on during charging, and the communication lamp 2b is turned on during data transfer.

  After the transfer of the biometric data from the sensor chip 1 to the power feeder 2, the biometric data is deleted from the memory 122 of the sensor chip 1. This data deletion is performed by an instruction of either the MCU 121 of the sensor chip 1 or the MPU 25 of the power feeder 2. (F) Thus, the sensor chip 1 charged with the biometric data deleted is sent again to obtain biometric data.

  As illustrated in FIG. 24, the power feeder 2 is preferably connected to a connection terminal 80 having a function of connecting to a public line, and the biometric data acquired from the sensor chip 1 is a server as an external device via the public line, for example. (Cloud server) Transfer to 81 or the like.

  The deletion of the biometric data from the memory 122 of the sensor chip 1 may be performed after confirming the data transfer to the server 81. The connection terminal 80 may be a personal computer, a mobile tablet, a microcomputer mounted board, or the like.

  On the server 81 side where the biometric data is transmitted from the power feeder 2, the physical ability, the stress state, the possibility of being sick or the state immediately before becoming sick, etc. from the amount of exercise, pulse change, heart rate fluctuation, respiratory rate, blood pressure change, etc. judge.

  In addition, a biosignal measurement program (for example, a biosignal measurement program related to climacteric disorder, orthostatic disorder, arrhythmia, etc., and a specific ST wave is monitored and stored in detail) is provided as needed. Write to the sensor chip 1 via the electrical device 2.

  At this time, the communication lamp 2b of the power feeder 2 is lit, but it is not necessarily required to be charging. That is, transfer of biometric data from the sensor chip 1 to the power feeder 2, transfer of biometric data from the power feeder 2 to the server 81, and program writing from the server 81 to the sensor chip 1 via the power feeder 2 1 may be performed before or after charging.

  As described above, according to the present invention, it is not necessary to provide a dedicated charging terminal such as an SD terminal by using an electrode for originally detecting a biological signal as a charging terminal, and the configuration of the biological signal measuring instrument. Is simplified, and further reduction in size, weight and thickness can be achieved, and sufficient waterproof measures can be taken.

  Further, only when the biological signal measuring instrument (sensor chip) is attached to the human body, the power activation switch is turned on and power is supplied from the battery to the biological signal processing circuit. In other cases, the power activation switch is off. Therefore, battery consumption can be reduced as much as possible.

1 Biological signal measuring instrument (sensor chip)
2 Power supply 10 (10a, 10b) Electrode 20 (20a, 20b) Power supply terminal 30, 40 Substrate 50 Low bending rigidity portion (flexible wiring board)
60 Waterproof cover 70 Adhesive tape for mounting 70a, 70b Skin side electrode 71a, 71b Connection electrode 100 Biological signal processing circuit 200 Charging circuit 300 Biological signal / feeding power distribution means

Claims (3)

Including a biological signal measuring instrument used by being attached to a living body,
The biological signal measuring instrument supplies a power to the biological signal processing circuit, a pair of electrodes that are in contact with the living body at the time of measuring the biological signal, a biological signal processing circuit that processes a biological signal detected by the electrodes, and the biological signal processing circuit. In a biological signal measuring device comprising a battery,
A power start switch for turning on and off the power supplied from the battery to the biological signal processing circuit, and a control unit for controlling the power start switch,
The control unit monitors an interelectrode resistance existing between the electrodes, and turns off the power supply start switch when the interelectrode resistance exceeds a predetermined threshold value, and turns off the power supply switch when the interelectrode resistance is equal to or lower than the threshold value. A biological signal measuring apparatus, wherein a power activation switch is turned on to supply power from the battery to the biological signal processing circuit.   The control unit has a two-input type comparator, the power supply voltage in the device is V0, and one input terminal of the comparator includes resistors R1 and R2 connected between the power supply in the device and the ground. A voltage V1 (= R2 / (R1 + R2)) obtained by dividing the power supply voltage V0 by a voltage circuit is applied, and the other input terminal of the comparator is connected between the one electrode and the in-device power supply. A voltage V2 (= R4 / () obtained by dividing the power supply voltage V0 by a voltage dividing circuit including a connected resistor R3, a resistor R4 connected between the other electrode and grunge, and the interelectrode resistor R5. R3 + R4 + R5)) is applied, the resistors R2, R3, R4 have the same resistance value Ra, the resistor R1 has a resistance value Rb higher than the resistance value Ra, and the threshold is defined as Rb-Ra. Features Biological signal measurement apparatus according to claim 1.   The biological signal measuring device according to claim 2, wherein the resistors R1 to R4 are high resistance elements having a current consumption of 1 µA or less.

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