JP3511030B2 - Biological signal detection device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biological signal detecting apparatus, and more particularly, to a living body for detecting a minute movement of a human body or an animal such as respiration or a heartbeat (pulse) by a magnetic sensor as a change of a static magnetic field accompanying the slight movement. The present invention relates to a signal detection device.

[0002]

2. Description of the Related Art Generally, an electrocardiograph is used for detecting and measuring respiration, heartbeat (pulse), etc. of a human body.

When the respiration and heartbeat (pulse) of the human body are detected and measured by an electrocardiograph, immediately before the measurement,
A number of electrodes derived from the electrocardiograph are attached to predetermined parts of the human body by tape or clipped and attached, after which the electrocardiograph is operated, and breathing and heartbeat ( (Pulse) etc. are detected and measured, and the detection results are displayed as a list on the graph as an electrocardiogram. When the measurement is completed, the plurality of electrodes attached in front are removed from the human body.

[0004]

By the way, the above-mentioned known electrocardiograph always attaches a plurality of electrodes to a predetermined portion of the human body when detecting and measuring minute movements of the human body such as respiration and heartbeat (pulse). It has to be removed or removed from the human body, and the time required to attach and detach multiple electrodes is longer than the actual measurement time for respiration and heartbeat (pulse) with an electrocardiograph. It has the problem of being annoying.

Further, in the known electrocardiograph, since a plurality of electrodes and the electrocardiograph are connected by a cord, when the plurality of electrodes are attached to a predetermined portion of the patient, the movement of the patient is reduced. Is significantly regulated, and has a problem of imposing a physical and mental burden on the patient, and in particular, during detection for a long time such as during sleep detection or home treatment, the patient cannot turn over. There are problems such as not being able to go to the toilet.

The present invention solves the above-mentioned problems.
The purpose is to detect and measure minute movements of the object to be measured, and it is not necessary to perform any operation on the object to be measured before and after the measurement, and the object to be measured is hardly burdened. It is to provide a signal detection device.

[0007]

In order to achieve the above object, the biological signal detecting device of the present invention is arranged in a static magnetic field.
Is, the object to be measured is placed, iron, an iron / nickel system, the deformable high permeability material such as cobalt-based sheet made of an amorphous alloy such as alloys, due to the tremor measured sample <br /> A magnetic sensor capable of detecting the deformation of the high magnetic permeability member as a change in the static magnetic field is used, and the detection output of the magnetic sensor is used as a biological signal.
And the deformable high magnetic permeability member arranged in a static magnetic field, such as a sheet , on which the measured object is placed, and the deformation of the high magnetic permeability member arranged below the member. Assist
That the deformation assisting member and a detectable magnetic sensor deformation as a change of the static magnetic field of high permeability material with the fine movement of the object to be measured
Used comprises a <br/> means to obtain the detection output of the magnetic sensor as the biometric signals.

According to these means, the fine movement of the measured object is transmitted to the high magnetic permeability member while the measured object is on the high magnetic permeability member, and the high magnetic permeability member is slightly deformed. By detecting and measuring the change of the static magnetic field due to the slight deformation by the magnetic sensor arranged in the vicinity of the high magnetic permeability member, it becomes possible to easily detect and measure the fine movement of the measured object.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the first embodiment of the present invention, a biological signal detecting device is arranged in a static magnetic field and is capable of mounting an object to be measured, such as an iron-based, iron / nickel-based, or cobalt-based alloy. A sheet-like deformable high-permeability member made of amorphous alloy, etc., and a high-permeability member are placed in the vicinity (including the contact position) of the high-permeability member to prevent deformation of the high-permeability member due to slight movement of the DUT. A magnetic sensor capable of detecting a change in the magnetic field is provided , and the detection output of the magnetic sensor is obtained as a biological signal .

Further, in the second embodiment of the present invention, the biological signal detecting device is arranged in a static magnetic field, and has a deformable high magnetic permeability member such as a sheet on which an object to be measured can be placed, It is placed under the high-permeability member and
A deformation assisting member for assisting the shape, and a magnetic sensor arranged in the vicinity of (including in contact with) the high magnetic permeability member and capable of detecting deformation of the high magnetic permeability member due to slight movement of the measured object as a change in static magnetic field. And the detection output of the magnetic sensor as a biological signal
Is obtained .

In this embodiment, the object to be measured is mounted.
An example of the high magnetic permeability member that can be placed is a human body to be measured.
If it is a sheet, it has a part wider than the shoulder width.
The deformable member of is used.

According to these embodiments, when a part or the whole of the object to be measured is superimposed on the high permeability member is transmitted to the high permeability member micromotion which is deformable in the body to be measured, in which The micro-deformation of the high-permeability member causes a slight deformation, and the change in the static magnetic field due to the micro-deformation of the high-permeability member is detected by the magnetic sensor arranged in the vicinity of the high-permeability member.
The output power is acquired as a biological signal .

In this case, since the object to be measured is merely placed on the high magnetic permeability member and there is nothing that restricts the movement, no operation is required on the object to be measured before and after the measurement. Moreover, there is almost no burden on the object to be measured.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIGS. 1 (a) and 1 (b) are block diagrams showing a first embodiment of a biological signal detecting apparatus according to the present invention.
(A) is a top view and (b) is a side view. Note that FIG.
The bed 6 is not shown in FIG.

As shown in FIG. 1, the biological signal detecting apparatus of this embodiment comprises a rectangular parallelepiped high-permeability sheet member 1 made of an amorphous alloy such as an iron-based alloy, an iron / nickel-based alloy, and a cobalt-based alloy. It is arranged under the magnetic permeability sheet member 1,
The deformation assisting member 2 having substantially the same outer shape as the high-permeability sheet member 1, the first magnetic sensor 3 arranged immediately below the peripheral edge portion of the high-permeability sheet member 1, and the position separated from the high-permeability sheet member 1. And a second magnetic sensor (another magnetic sensor) 4 arranged in the.

The high-permeability sheet member 1 and the deformation assisting member 2 are arranged on the bed 6, and the person 5 to be measured turns his or her head eastward on the high-permeability sheet member 1 and the deformation assisting member 2. It is possible to ride in a sleeping state, and the width {dimension in the up-down direction of FIG. 1 (a), that is, the north-south direction} is wider than the shoulder width of the person to be measured 5, and the length {FIG. 1 ( The dimension in the left-right direction of a), that is, the dimension in the east-west direction} is selected as a dimension that covers the entire chest and a part of the abdomen of the subject 5. In addition, the first magnetic sensor 3
Is arranged on one side in the width direction of the high-permeability sheet member 1, that is, at the lower part of the bed 6 which is directly below the peripheral edge portion on the south side, and the second magnetic sensor 4 has a high magnetic permeability at the same position in the width direction as the first magnetic sensor 3. It is arranged under the bed 6 at a position away from the magnetic susceptibility sheet member 1. Furthermore, the first magnetic sensor 3 and the second magnetic sensor 4 are separated from the floor by the same distance,
The magnetic sensors 3 and 4 are arranged in the same direction and have the same characteristics.

In this case, the high-permeability sheet member 1 is a high-permeability material having a magnetic permeability higher than that of pure iron, for example, an iron-based or iron / nickel-based material having a relative magnetic permeability of about 8000 or more,
Amorphous alloy made of cobalt alloy, etc., or
Iron / nickel alloy, nickel content ratio (weight ratio)
Of 35 to 80% is selected. The amorphous alloy contains iron, nickel and cobalt as main components, and boron (B), chromium (Cr), molybdenum (M
o), commercially available products containing a small amount of carbon (C) and the like are included. Such an amorphous alloy has a high magnetic permeability, and when formed into a sheet, it can be made relatively thin, so that it can be easily deformed by an external force. On the other hand, although permalloy has a higher magnetic permeability than pure iron, it is more thin than the amorphous alloy in terms of flexibility and the degree of deformation due to external force because the thinning of the sheet is limited when formed into a sheet. Although inferior, it is more advantageous than amorphous alloys in terms of cost.

Further, the thickness of the high-permeability sheet member 1 needs to be deformed or displaced in accordance with the slight movement of the person 5 to be measured on it, so that it is practically 0.2 mm or less. The thickness of The dimension of the high-permeability sheet member 1 is wider than the shoulder width of the person to be measured 5, preferably long, in consideration of the case where the person to be measured 5 riding on the sheet member 1 moves before or during the measurement. Considering the measurement of time,
In order to continue the measurement even when the person to be measured 5 turns over, a person with a shoulder width of about twice or more of the person to be measured 5 is selected, and at least the entire chest (heart) of the person to be measured 5 can be covered. In view of the difference in height of the person to be measured 5, variations in the riding position, etc., a length that can cover the entire chest area and part of the abdomen of the standard person 5 to be measured is selected. In this embodiment, the high-permeability sheet member 1 has a rectangular shape that is long in the shoulder width direction of the person to be measured 5, but other shapes, for example, the length direction is extended and the shoulder width direction is longer than the length direction. It may have a rectangular shape, a circular shape, or an elliptical shape having a short length.

Further, the high-permeability sheet member 1 is not limited to one made of a continuous sheet, but a plurality of sheets are combined into one sheet, or a ribbon-shaped material is knitted. It may be one sheet-shaped body, or may be one sheet-shaped body formed by knitting a linear wire of 0.2 mm or less. In particular, the sheet-shaped body formed by knitting is There is an advantage that it is easily deformed or displaced with respect to fine movement.

Although not shown in FIG. 1, a thin cloth such as sheets may be laid on the high-permeability sheet member 1 and the person to be measured 5 may ride on it to perform the measurement.

Next, the deformation assisting member 2 has a high magnetic permeability sheet member 1 so that the high magnetic permeability sheet member 1 is easily deformed or displaced by a slight movement of the person 5 to be measured on the high magnetic permeability sheet member 1. Of the non-ferromagnetic material, which is more flexible than the high-permeability sheet member 1, for example, sponge made of foam such as urethane foam, and has elasticity such as elastomer member such as silicon rubber. A cushion member or the like is used. Since the size of the deformation assisting member 2 assists the deformation or displacement of the high magnetic permeability sheet member 1, it should be the same as or slightly larger than the size of the high magnetic permeability sheet member 1. The thickness of the deformation assisting member 2 varies depending on the constituent material, but is generally within the range of 3 mm to 100 mm. In addition to this, the bed 6 may be provided with the function of the deformation assisting member 2, and the high magnetic permeability sheet member 1 may be arranged on the bed 6 which is the deformation assisting member 2. May be used instead of.

Next, the first and second magnetic sensors 3, 4
Is required to detect a weak static magnetic field such as geomagnetism, a high-sensitivity magnetic sensor, for example, a flux gate method in which a primary coil (toroidal coil) and a secondary coil (output coil) are wound around a toroidal core. Magnetic sensor (hereinafter referred to as FGS) is used.

2 (a) and 2 (b) are configuration diagrams showing an example of the configuration of the FGS, (a) is an exploded perspective view thereof, and (b) is an explanatory diagram showing its operation principle. .

As shown in FIG. 2A, the FGS is
Toroidal core C by stacking multiple permalloy rings
The primary coil (toroidal coil) L ₁ is wound substantially evenly along the toroidal core C, and the secondary coil (output coil) L ₂ is wound by giving directionality in the radial direction of the toroidal core C. It has a structure. Note that FIG.
The FGS shown in (a) is provided with an X coil and a Y coil as a secondary coil and can detect a magnetic field in two orthogonal axial directions, but the FGS is not limited to this, and at least 1
Any magnetic field in the axial direction can be detected.

As shown in FIG. 2B, when the geomagnetism passes through the toroidal core C, if the amount of current supplied to the primary coil L ₁ is increased, the current will flow to the toroidal core C.
Increases until it becomes magnetically saturated, but due to the effect of geomagnetism,
The region a on the toroidal core C is magnetically saturated for a moment earlier than the region b. This time, imbalance of increased upward flux and downward flux in the secondary coil L _2, apparently, the magnetic flux passing through the secondary coil L ₂ becomes to have changed, from the secondary coil L ₂ The pulse voltage is output. The magnitude of this pulse voltage depends on the toroidal core C
Since it depends on the strength of the earth's magnetism passing through, it is possible to detect the earth's magnetism by looking at the magnitude of the pulse voltage.

The detection sensitivity of the FGS depends on the material and size of the toroidal core C, the number of turns of the primary coil L ₁ and the secondary coil L ₂ . Therefore, the material of the toroidal core C has a high magnetic permeability, good frequency characteristics on the high frequency side (having a low magnetic permeability even when the frequency becomes high), a high squareness ratio, and a small coercive force. Is usually selected, and is usually a low-cost material compared to amorphous materials such as permalloy (PA, PC grade) and supermalloy, or iron alloy
BR> Fus, iron / nickel alloy amorphous, cobalt alloy amorphous, etc., which have higher magnetic permeability and can be miniaturized, or materials such as ferrite, which are lower cost than permalloy, are used. In addition, the secondary coil L ₂
A large pulse voltage can be output by increasing the number of windings, and the FGS can obtain higher detection sensitivity than other magnetic sensors such as Hall elements.

The first magnetic sensor 3 and the second magnetic sensor 4 are not limited to those using FGS, and may be magnetic impedance elements (MI elements), Hall elements, magnetic resistance elements (MR elements), or the like. You may use. And the first
When a Hall element or the like having a relatively low detection sensitivity is used as the magnetic sensor 3 and the second magnetic sensor 4, in order to supplement the detection sensitivity, a magnetism collecting element made of a material having a high magnetic permeability, for example, an inverted cone shape is used. A magnetic sensor arranged close to a Hall element or the like is used.

Next, FIG. 3 is a block diagram showing an example of a processing circuit for analog-processing the fine movements obtained by the first magnetic sensor 3 and the second magnetic sensor 4 in the embodiment shown in FIG. 4 is a signal waveform diagram showing a signal state of each part in the processing circuit shown in FIG.

As shown in FIG. 3, the processing circuit includes a first
Magnetic sensor 3, second magnetic sensor 4, and amplifier circuits 7 and 8
, Detection circuits 9, 10, integration circuits 11, 12, low-pass filters 13, 14, resistance distribution circuit 15, FG
The S drive circuit 16, the clock generation circuit 17, and the subtraction circuit 18 are provided.
Nos. 18 to 18 are connected to each other as shown in FIG. Then, the first magnetic sensor 3 and the second magnetic sensor 4
Are both made of FGS having the same characteristics. As shown in FIG. 1, the first magnetic sensor 3 is arranged immediately below the peripheral edge of the high magnetic permeability sheet member 1, and the second magnetic sensor 4 has high magnetic permeability. It is arranged at a position away from the sheet member 1. Note that, here, for simplicity, a secondary coil (output coil)
Will be described as detecting a magnetic field only in one axis direction, but a signal from the magnetic sensor can be processed by a similar processing circuit in the case of detecting two or three axis directions orthogonal to each other.

The processing circuit configured as described above operates as follows.

The clock generation circuit 17 includes a square wave drive timing signal of 3.8 KHz as shown in the signal waveform a in the first stage of FIG. 4 and a signal 7.b as shown in the signal waveform b in the second stage of FIG. A 6 KHz square wave detection timing signal is generated, a drive timing signal is supplied to the FGS drive circuit 16, and a detection timing signal is supplied to the two detection circuits 9 and 10.
The FGS drive circuit 16 generates an AC drive signal (rectangular wave AC voltage) in response to the supplied drive timing signal. The resistance distribution circuit 15 distributes an AC drive signal, whereby a drive current in which the magnitude of the current sequentially increases in the positive direction and the negative direction is applied to the primary coil (toroidal coil) of the first magnetic sensor 3 and the drive current. 2 It flows into the primary coil (toroidal coil) of the magnetic sensor 4, respectively.

First magnetic sensor 3 and second magnetic sensor 4
Is due to the supplied drive current, the toroidal core reaches the magnetic saturation state in one direction of the magnetic flux from the magnetic unsaturated state,
After that, by reversing the polarity of the drive current, the magnetic flux enters the magnetic saturation state in the other direction of the magnetic flux through the magnetic saturation state. As described above, in the first magnetic sensor 3 and the second magnetic sensor 4, the toroidal core sequentially repeats the states of magnetic saturation, magnetic saturation in one direction, magnetic saturation, magnetic saturation in the other direction, and magnetic saturation. Then, the voltage across the terminals of the primary coils (toroidal coils) of the first magnetic sensor 3 and the second magnetic sensor 4 is toroidal after the current polarity is reversed, as shown by the signal waveform c in the third stage of FIG. A large value is shown until the core is magnetically saturated, and a small value is shown at the moment when the toroidal core is magnetically saturated.

First magnetic sensor 3 and second magnetic sensor 4
Is affected by the geomagnetism present in the ground space. Here, as described above with reference to FIG. 2B, between the magnetic non-saturation and the magnetic field between one region (region corresponding to the region a) and the other region (region corresponding to the region b) of the toroidal core. There is a slight deviation between the saturation time and the magnetic saturation time. At this time, in each of the secondary coils (output coils) of the first magnetic sensor 3 and the second magnetic sensor 4, the magnetic flux in one direction (for example, upward in FIG. 3) and the other direction (for example, in the axial direction) in the axial direction. The balance of the increase or decrease with the magnetic flux (downward in FIG. 3) is lost, and the magnetic flux passing through the secondary coil (output coil) is apparently changed.
A pulse voltage as shown by the signal waveform d in the fourth stage of FIG. 4 is output. That is, the drive voltage continues to be applied in the same direction at the moment when the polarity of the drive current is reversed (transition from core saturation to non-saturation), and a pulse voltage is generated at the moment when transition from non-saturation to saturation occurs.

The amplifier circuit 7 amplifies the pulse voltage output from the secondary coil (output coil) of the first magnetic sensor 3 to generate an amplified pulse voltage as shown by the signal waveform e in the fifth stage of FIG. To do. The amplifier circuit 8 amplifies the pulse voltage output from the secondary coil (output coil) of the second magnetic sensor 4, and similarly generates an amplified pulse voltage.

The detection circuit 9 constitutes an analog buffer which functions as an inverting amplifier having a gain of 1 or a non-inverting amplifier having a gain of 1, and has a binary polarity (high or low) of the supplied detection timing signal. Inversion and non-inversion of the polarity are controlled correspondingly, and the input amplified pulse voltage is
It is converted into a unipolar pulse voltage as shown in the signal waveform f of the stage. That is, the amplified pulse voltage has different polarities between the first pulse output at the time of transition from magnetic saturation to magnetic saturation and the second pulse output at the time of transition from magnetic saturation to magnetic saturation. , The negative polarity first in the detection circuit 9
When the pulse is supplied, the detection circuit 9 works as an inverting amplifier so that the polarities of the first and second pulses in the output of the detection circuit 9 are both positive. It should be noted that the frequency of the drive timing signal and the resistance values of the resistance distribution circuit 15 are adjusted according to the characteristics of the two magnetic sensors 3 and 4 so that the second pulse is generated at the temporal intermediate position between the two first pulses. Is selected, which can simplify the clock generation circuit 17. Further, the detection circuit 10 also performs the same operation as the detection circuit 9 and obtains a unipolar pulse voltage.

The integrating circuit 11 outputs 1 output from the detecting circuit 9.
The polarity pulse voltage is integrated to remove the drive timing signal and detection timing signal components contained in one polarity pulse voltage. In addition, the integrating circuit 12 also includes the integrating circuit 11
The same operation as is performed.

The low-pass filter 13 has a cutoff frequency of about 20 Hz, and removes the commercial power source frequency component contained in the integrated output of the integrating circuit 11. By the way, the heart rate of the subject 5 (human body) is 1 to 2 Hz.
Therefore, it is not removed by the low-pass filter 13, and the output of the low-pass filter 13 indicates 7 in FIG.
As shown in the signal waveform g of the step, a signal including the respiration and the heartbeat of the person to be measured 5 is obtained. In the signal, noise such as an external magnetic field that is not related to the respiration and the heartbeat of the person to be measured 5 is obtained. Contains ingredients. Further, the low-pass filter 14 has the same configuration as the low-pass filter 13 and has the same function, but the output of the low-pass filter 14 is as shown in FIG.
As shown in the signal waveform h in the eighth step of No. 5, the noise component such as an external magnetic field that does not substantially include the respiration and the heartbeat of the person to be measured 5 is the main one.

The subtraction circuit 18 subtracts the output signal of the low-pass filter 13 and the output signal of the low-pass filter 14, and most of the noise components such as the external magnetic field are canceled by this subtraction, and the ninth stage in FIG. As shown in the signal waveform i of FIG. 3, a signal mainly including only the respiration and heartbeat of the measured person 5 included in the output signal of the low-pass filter 13 is obtained.

The signal waveforms a to i shown in FIG.
In the figure, the horizontal axis represents time, but the time of the signal waveforms g to i is compressed compared to the time of the signal waveforms a to f.

Here, FIG. 7 is a waveform diagram showing a slight movement of the human body obtained by the biological signal detecting apparatus of this embodiment.

The waveform shown in FIG. 7 shows the measurement results in the normal state and in the state in which breathing is stopped. The first half part (a part) is a breath mainly composed of a large swell. The state (the heartbeat is superimposed) is dominant, and the second half (the part of (b)) shows the heartbeat state which is composed of fine waves exclusively.

Next, FIG. 5 is a block diagram showing an example of a processing circuit for digitally processing the fine movements obtained by the first magnetic sensor 3 and the second magnetic sensor 4 in the embodiment shown in FIG. FIG. 6 is a signal waveform diagram showing a signal state of each part in the processing circuit shown in FIG.

In FIG. 5, the same components as those shown in FIG. 3 are designated by the same reference numerals.

As shown in FIG. 5, there is a structural difference between this processing circuit (hereinafter referred to as a digital processing circuit) and the processing circuit illustrated in FIG. 3 (hereinafter referred to as an analog processing circuit). By comparison, the analog processing circuit includes a clock generation circuit 17 and a subtraction circuit 18, while the digital processing circuit includes two analog-digital (AD) converters 19 and 20 and a microcomputer 21. Other than that, there is no other structural difference between the digital processing circuit and the analog processing circuit.

The operation of the digital processing circuit is FGS.
The drive timing signal supplied to the drive circuit 16 and the detection timing signal supplied to the two detection circuits 9 and 10 are formed by the microcomputer 21, and the output signal waveform g of the low-pass filter 13 is the AD converter 1
In FIG. 9, the output signal waveform h of the low-pass filter 14 is digitized by the AD converter 20 and then output as digital data digitally subtracted by the microcomputer 21, which is the operation of the analog processing circuit described above. The operation is the same as that of the analog processing circuit described above except for the difference.

Therefore, further detailed description of the operation of the digital processing circuit will be omitted.

Next, FIGS. 8A and 8B are configuration diagrams showing a second embodiment of the biological signal detecting apparatus according to the present invention, wherein FIG. 8A is a top view and FIG. 8B is a side view. It is a figure. The bed 6 is not shown in FIG.

As shown in FIG. 8, the biological signal detecting apparatus according to the second embodiment has a rectangular shape elongated in the north-south direction (the shoulder width direction of the person to be measured 5) made of the amorphous alloy shown in the first embodiment. Of the high magnetic permeability sheet member 1, the deformation assisting member 2 arranged below the high magnetic permeability sheet member 1, the first magnetic sensor 3 housed in the hole 22 provided in the deformation assisting member 2, And a second magnetic sensor 4 which is another magnetic sensor arranged at a position distant from the magnetic permeability sheet member 1, and the high magnetic permeability sheet member 1 and the deformation assisting member 2 are
Similar to the embodiment of FIG.
In FIG. 8B, the bed 6, the deformation assisting member 2, the high-permeability sheet member 1 and the person to be measured 5 are illustrated as being slightly separated from each other, but this is for the sake of easy understanding of the drawing. In fact, of course, these are in contact. This point is the same in FIG. 1B of the first embodiment.

The greatest difference between the second embodiment and the first embodiment is the arrangement position of the first magnetic sensor 3. That is, when the person to be measured 5 lies on the deformation assisting member 2 and the high-permeability sheet member 1 with his / her head facing east, for example, the chest of the person 5 having large body movement (body movement) ( More preferably, in order to be able to dispose the first magnetic sensor 3 directly under the high-permeability sheet member 1 in a portion where the heart portion is located, the first magnetic sensor is provided on the deformation assisting member 2 including an elastic cushion member or the like. A hole 22 for housing 3 is formed. The hole 22 may be a hole having a bottom which does not penetrate but may penetrate the deformation assisting member 2. Here, the deformation assisting member 2 needs to have a certain thickness in order to accommodate the first magnetic sensor 3, and a member having a thickness of 5 mm to 100 mm is selected. Then, the FGS having a thickness equal to or smaller than that of the deformation assisting member 2
In the first magnetic sensor 3 consisting of, the toroidal core has a horizontal plane parallel to the plane of the high-permeability sheet member 1, and the axial direction of the secondary coil of the first magnetic sensor 3 faces north-south. 1 The magnetic sensor 3 and the high-permeability sheet member 1 are housed in the hole 22 in a state of being in contact with each other. The first magnetic sensor 3 is not necessarily in contact with the high-permeability sheet member 1, but the closer to the high-permeability sheet member 1, the larger the biomedical signal can be detected.

The second magnetic sensor 4 is for obtaining a differential signal with respect to the first magnetic sensor 3, and therefore, the characteristic is the same as that of the first magnetic sensor 3 and its direction is also the same. It matches the first magnetic sensor 3. Then, the arrangement position of the second magnetic sensor 4 is located on the west side of the first magnetic sensor 3 distant from the high magnetic permeability sheet member 1 so as not to be affected by the change of the magnetic flux due to the deformation of the high magnetic permeability sheet member 1. The position is the same as the height of the first magnetic sensor 3 in the extension direction.

As is apparent from FIG. 8, the deformation assisting member 2 has substantially the same width as the high-permeability sheet member 1, and when the subject 5 lies on the bed 6, the subject It has a rectangular shape that is long in the east-west direction and has a length longer than the length from the head to the legs. This is because the deformation assisting member 2 needs to have a certain thickness (5 mm to 100 mm) in order to house the first magnetic sensor 3 as described above. As shown, when the dimension is similar to that of the high-permeability sheet member 1, the measured person 5 has a posture in which only a part of the abdomen from the shoulder is pushed up by the thickness of the deformation assisting member 2, Although a load is imposed on the person to be measured 5, as described above, if the deformation assisting member 2 has a length equal to or greater than the height of the person to be measured 5, such a burden can be eliminated. Strictly speaking,
The thickness of the high-permeability sheet member 1 is also added.
The thickness is 0.2 mm or less, which is smaller than the thickness of the deformation assisting member 2 and can be ignored.

It should be noted that the FGS is not a copper wire wound around a toroidal core, but a thin one having a thickness of about 1.5 mm to 2 mm in which the FGS is formed by using a multilayer printed wiring technique. If FGS is used, the deformation assisting member 2 can also be made thin, and in this case, the deformation assisting member 2 having an outer shape having substantially the same dimensions as the high magnetic permeability sheet member 1 as in the first embodiment is used. However, the measured person 5 is not so burdened.

The signal processing circuit and its operation of the biological signal detecting apparatus according to the second embodiment are basically the same as those of the first embodiment described above.
Since it is the same as the biological signal detecting apparatus according to the embodiment, the description thereof will be omitted.

In the second embodiment as well, since the difference output (differential signal) of the detection outputs of the first magnetic sensor 3 and the second magnetic sensor 4 is obtained, noise components such as an external magnetic field are eliminated. It can be removed, and the biological signal due to the slight movement of the person to be measured 5 can be accurately detected.

In the second embodiment, the first
Since the magnetic sensor 3 is arranged in contact with the high-permeability sheet member 1, the change in the magnetic field distribution at the arrangement position of the first magnetic sensor 3 due to the slight movement of the person to be measured 5 becomes large, and the person to be measured becomes large. It is possible to reliably detect the biological signal 5 as a large signal.

Further, the arrangement position of the first magnetic sensor 3 is
Since the chest (heart) of the person to be measured 5 is located in a region where body movement is large, the first magnetic sensor 3
At the arrangement position of, the high-permeability sheet member 1 is largely deformed due to the fine movement of the person to be measured 5, and the deformation also causes a large change in the magnetic field distribution. Therefore, a large biological signal is generated by the first magnetic sensor 3. Can be detected.

The orientation of the first magnetic sensor 3 is not limited to that of the second embodiment described above, but the horizontal plane of the toroidal core and the plane of the high-permeability sheet member 1 are perpendicular or less (90 degrees or less). ) May be arranged so as to intersect with each other, and the axial direction of the secondary coil may be oriented in a direction other than north and south. This is because the first magnetic sensor 3 is arranged immediately below the high-permeability sheet member 1 in a region where body movement is large and in contact with the high-permeability sheet member 1 as described above. At the arrangement position of 3, the change of the magnetic field distribution due to the slight movement of the person to be measured 5 becomes extremely large, and no matter how the orientation of the first magnetic sensor 3 is changed, the change of the magnetic field distribution causes the first magnetic sensor to change. This is because a component interlinking with the secondary coil of No. 3 is included.

In the second embodiment described above, the deformation assisting member 2 is placed on the bed 6, but the bed 6 functions as the deformation assisting member 2 and becomes the deformation assisting member 2. It is also possible to embed the first magnetic sensor 3 in 6.

Further, as a modification of the second embodiment, a large number of holes are formed dispersedly in the deformation assisting member 2, the first magnetic sensor 3 is housed in each hole, and each first magnetic sensor 3 is formed.
It is also possible to take a differential signal between the second magnetic sensor 4 and the second magnetic sensor 4. With this configuration, even if the height of the person to be measured 5 is different or the person to be measured 5 rolls over and the position of large body movement on the high-permeability sheet member 1 changes, either 1 A large output is obtained from the magnetic sensor 3, and by adopting the large output as a biological signal, regardless of the height of the person to be measured 5 or whether or not the person turns over.
The biological signal can always be detected reliably.

Next, FIG. 9 is a block diagram showing a third embodiment of the biological signal detecting apparatus according to the present invention.

As shown in FIG. 9, in the biological signal detecting apparatus according to the third embodiment, the high magnetic permeability sheet member 1 and the deformation assisting member 2 arranged below the high magnetic permeability sheet member 1 are provided.
(Not shown), and two of the four corners of the high-permeability sheet member 1 are arranged directly below the south corner.
Two first magnetic sensors 3 (1), 3 (2) and two first magnetic sensors 3 arranged at the north corners, respectively.
(3) 3 (4) and two second magnetic sensors 4 (1), 4 (2) which are other magnetic sensors arranged on the south side and the north side, respectively, apart from the high-permeability sheet member 1. And the orientation and characteristics of each magnetic sensor are the same. The high-permeability sheet member 1 and the deformation assisting member 2 are arranged on the bed 6 (not shown) in the same manner as in the first embodiment.

The operation of the biological signal detecting apparatus according to the third embodiment is basically the same as the operation of the biological signal detecting apparatus according to the first embodiment described above, and therefore the description of the operation will be omitted.

In the third embodiment, the two first magnetic sensors 3 in the same width direction of the high magnetic permeability sheet member 1 are used.
Using the detection outputs of (1) and 3 (2), a difference output (first difference output and second difference output) from the detection output of the second magnetic sensor 4 (1) is generated for each of those detection outputs. Let
Similarly, a difference output (third difference output and fourth difference output) between each of the detection outputs of the two first magnetic sensors 3 (3) and 3 (4) and the detection output of the second magnetic sensor 4 (2). Generate. If a plurality of differential outputs are obtained in this way and one of the first to fourth differential outputs having the highest level is adopted as the biological signal, it is assumed that the measured person 5 moves and a large signal is obtained. Even if the first magnetic sensor changes from 3 (1) to 3 (4), for example, the measured person 5
It becomes more difficult to overlook the slight movements and the biological signal can be detected more reliably.

If a large number of differential outputs are obtained in this way, for example, one side of the bed 6, for example, the first magnetic sensors 3 (1), 3 (2) and the second magnetic sensor 4 (1).
Even if there is a wall such as a steel frame near the side (south side) and the geomagnetism is distorted by it, the other side of the bed 6 (north side), the first magnetic sensors 3 (3), 3 (4) and Second
If the detection output obtained on the magnetic sensor 4 (2) side is used, it becomes possible to detect a more accurate fine movement of the measured person 5.

As a modification of the third embodiment, the two second magnetic sensors 4 (1) and 4 (2) are not used, and only one second magnetic sensor 4 is used as another magnetic sensor. This second magnetic sensor 4 is arranged at an intermediate portion of the arrangement points of the two second magnetic sensors 4 (1), 4 (2) (disposed at the tip of the leg of the person to be measured 5), and the first magnetic sensor 4 is used. Sensor 3
Difference outputs between the detection outputs of (1), 3 (2), 3 (3), and 3 (4) and the detection output of the second magnetic sensor 4 are obtained to obtain the first to fourth difference outputs. You may do it.

Furthermore, as another modification of the third embodiment, the two first magnetic sensors 3 (1), 3 (without the second magnetic sensors 4, 4 (1), 4 (2) are used. 3) detection output difference output (fifth difference output) or two first magnetic sensors 3 (2), 3 (4) detection output difference output (sixth difference output)
Even if only this is used, a relatively large detection output can be obtained, and noise components due to the external magnetic field can be removed. This is because the magnetic flux due to geomagnetism is facing north-south, and the two first magnetic sensors 3 (1), 3
The location of (2) and the two first magnetic sensors 3 on the north side
Since it is considered that the density of the magnetic flux is opposite to the arrangement positions of (3) and 3 (4), the two first magnetic sensors 3
While the two detection signals obtained in (1) and 3 (2) and the two detection signals obtained in the two first magnetic sensors 3 (3) and 3 (4) have opposite phases to each other. ,
This is because the noise components due to the external magnetic flux have the same phase, so most of the noise components are canceled and the detection signals are added in the fifth difference output or the sixth difference output. That is, the first magnetic sensor 3 (3) is the first magnetic sensor 3 (1).
, And the first magnetic sensor 3 (4) similarly functions as another magnetic sensor for the first magnetic sensor 3 (2).

Next, FIG. 10 is a block diagram showing a fourth embodiment of the biological signal detecting apparatus according to the present invention.

As shown in FIG. 10, the biological signal detecting device according to the fourth embodiment has a high-permeability sheet member 1 and a deformation assisting member 2 disposed below the high-permeability sheet member 1.
(Not shown), and one first magnetic sensor 3 arranged immediately below the peripheral edge which is one south side in the width direction of the high-permeability sheet member 1, and is the same as the first embodiment. The high-permeability sheet member 1 and the deformation assisting member 2 are arranged on the bed 6 (not shown) in an overlapping manner.

The operation of the biological signal detecting apparatus of the fourth embodiment uses only the detection output of the first magnetic sensor 3,
That is, it differs from the operation of the biological signal detecting apparatus of the first embodiment in that it does not take a differential signal with respect to the detection output of the second magnetic sensor 4, but it is basically different from the operation described above. The operation is the same as that of the biological signal detecting apparatus according to the first embodiment, and thus the description of the operation is omitted.

In the fourth embodiment, since the noise component due to the external magnetic flux is not removed, the accuracy of the detection output is reduced accordingly, but the level of the detection output is larger than that of the noise component. There is no major obstacle, especially
There is no problem when detecting minute movements due to breathing.

As a modified example of the fourth embodiment, the characteristics are provided on one side in the width direction of the high-permeability sheet member 1, for example, just below the peripheral edge on the south side and immediately above the peripheral edge on the same side (south side). The same first magnetic sensors 3, 3 are arranged so that their directions are aligned with each other, and preferably, the distance between the first magnetic sensor 3 directly below and the high magnetic permeability sheet member 1 and the first magnetic sensor 3 immediately above and the high magnetic permeability sheet are high. The first magnetic sensor 3 and the third magnetic sensor 3 are arranged so as to overlap each other when viewed from directly above in a plane with the same distance from the member 1, and the difference between the detection outputs of these two first magnetic sensors 3 and 3 is arranged. The output may be used. By doing so, a relatively large detection output can be obtained, and noise components due to the external magnetic field can be removed. This is where the two first magnetic sensors 3, 3 are arranged,
That is, since it is considered that the density of the magnetic flux is opposite between the upper side and the lower side of the same side of the high-permeability sheet member 1, the detection signals obtained by the two first magnetic sensors 3 and 3 are in opposite phases. On the other hand, since the noise components due to the external magnetic field are in phase, most of the noise components are canceled in the difference output, and the detection signals are added. That is, one of the two first magnetic sensors 3 and 3 (for example, the first magnetic sensor 3 arranged above the high magnetic permeability sheet member 1) functions as the other magnetic sensor. In this modification, the first magnetic sensor 3 located on the upper side of the high-permeability sheet member 1 is arranged so as not to interfere with the person to be measured 5.

Throughout the first to fourth embodiments, at least the location of the first magnetic sensor 3, 3 (1) to 3 (4) should be as close to the high magnetic permeability sheet member 1 as possible. More preferably, the position is in contact with the high-permeability sheet member 1 as in the second embodiment, but when the deformation assisting member 2 and the bed 6 are interposed, the separation distance should be about 20 to 40 cm. If there is no problem in practice. And if the first magnetic sensors 3, 3 (1) to 3
When the detection sensitivity of (4) is low, the FGS is configured 2
The number of turns of the next coil (output coil) may be increased, and the plurality of first magnetic sensors 3, 3 (1) to 3 (4) may be provided.
When arranging, it is preferable that the distance from the high-permeability sheet member 1 be substantially the same. Furthermore, when arranging the second magnetic sensors 4, 4 (1), 4 (2), the distance between the second magnetic sensors 4, 4 (1), 4 (2) from the floor and the first magnetic sensor It is preferable that the sensors 3, 3 (1) to 3 (4) have substantially the same distance from the floor, and at least the directions of the magnetic sensors that produce a differential output are substantially the same.

In each of the above-mentioned first, third and fourth embodiments, the first magnetic sensor is arranged directly below the peripheral edge portion (corner portion) of the high magnetic permeability sheet member 1, but the peripheral edge portion is not always required. Does not need to be directly below the high magnetic permeability sheet member 1 and is located at a position where the deformation of the high magnetic permeability sheet member 1 can be detected.
It may be separated from each other, or conversely, may enter the inside of the high-permeability sheet member 1 from the peripheral portion. Then, when the first magnetic sensor is arranged inside the peripheral portion of the high-permeability sheet member 1, as described in the second embodiment, the chest (heart) where the body movement of the person to be measured 5 is large. It is preferable that the sheet is directly below the high-permeability sheet member 1 at the position where is located.

Further, when the FGS is used as the first magnetic sensor 3 and the second magnetic sensor 4, the secondary coil (output coil) is not limited to being wound only in one axial direction.
As shown in (a), a coil in which a secondary coil (output coil) is wound in two axial directions or a coil capable of detecting a magnetic field in three axial directions may be used.

In this case, the FGS in which the secondary coil (output coil) is wound only in the one axis direction is arranged so that the horizontal plane of the toroidal core is substantially perpendicular to the high magnetic permeability sheet member 1. And a secondary coil (output coil)
By arranging so that the axis direction of does not face east and west, the linkage with the geomagnetism is surely achieved, and the detection of the biomedical signal is ensured. For this reason, in each of the first, third, and fourth embodiments, the FGS has such an orientation.
The direction of is not limited to this, as described in the second embodiment. In addition, FIG. 1, FIG. 8 to FIG.
The first magnetic sensors 3, 3 (1) to 3 (4) and the second magnetic sensors 4, 4 (1), 4 (2) shown in FIG. 6 merely indicate the arrangement positions of the respective magnetic sensors. .

On the other hand, the FGS for detecting the biaxial direction or the triaxial direction has no limitation on the arrangement state, and the detection output can be obtained from the secondary coil (output coil) in any axial direction.

In each of the above embodiments, the person to be measured 5
The bed 6 is arranged so that when the person lays on the bed 6, the head of the person to be measured 5 faces the east side and the legs face to the west side, but the arrangement of the bed 6 is not limited to this, and The head may face any direction such as west, south or southeast.

Further, the high-permeability sheet member 1 is the subject 5
In the shoulder width direction (the direction of the line connecting the left shoulder and the right shoulder when the measured person 5 is lying on his / her back), and the high-permeability sheet member 1 is arranged so that this width direction faces north and south. This arrangement direction is also not limited to this.

Furthermore, in each of the first, third and fourth embodiments, the first magnetic sensor 3, 3 (1), 3 (2) and the second magnetic sensor 3 are used.
The magnetic sensors 4, 4 (1) are arranged at the peripheral edge of the high-permeability sheet member 1 on the south side and the lower side in the extension direction thereof, and the first magnetic sensors 3 (3), 3 (4) and the second magnetic sensor are arranged. Four
Although (2) is arranged on the north side of the high-permeability sheet member 1 and on the lower side in the extension direction thereof, the location (direction) of the magnetic sensor is not limited to this. It may be on the southeast side of the magnetic susceptibility sheet member 1, in the vicinity of the peripheral portion in the west-northwest, or even on the lower side in the vicinity of the center of the high magnetic permeability sheet member 1 as measured in the second embodiment. It is possible to detect the change in the magnetic field distribution due to the slight movement of the person 5.

However, when using geomagnetism as the static magnetic field and arranging the first magnetic sensor in the vicinity of the peripheral edge of the high-permeability sheet member 1, the preferable positions of the first magnetic sensor are the first, the third and the third. As shown in the fourth embodiment, it is in the vicinity of at least one peripheral edge portion in the north-south direction of the high-permeability sheet member 1, that is, in the vicinity of the end portion on the north side or the end portion on the south side. This is because the magnetic flux due to the earth's magnetism passes north and south (the rotation axis of the earth and magnetic north do not coincide with each other, so the angle of deviation is several degrees depending on the region), and the high permeability sheet member 1 This causes the magnetic flux to be bent and concentrated on the high-permeability sheet member 1, so that the magnetic flux changes due to slight movement of the person to be measured 5 in the vicinity of the periphery of the high-permeability sheet member 1 in the north-south direction, which serves as the entrance and exit of the magnetic flux. This is because it is considered that (change in magnetic field distribution) becomes large. For this reason, when the first magnetic sensor is arranged in the vicinity of the peripheral portion of the high magnetic permeability sheet member 1, the first magnetic sensor is irrelevant to the first magnetic sensor regardless of the arrangement of the bed 6 and the shape and arrangement direction of the high magnetic permeability sheet member 1.
As the location of the magnetic sensor, the high magnetic permeability sheet member 1
It is desirable to set it in the vicinity of at least one peripheral portion in the north-south direction. Further, the preferred location of the second magnetic sensor is a position where the noise component due to the external magnetic field is the same as that of the first magnetic sensor, and is generally at the same height as the first magnetic sensor and the side wall. It is the same distance from etc.

Further, the magnetic sensor is used as the high magnetic permeability sheet member 1.
The magnetic sensor is arranged on the lower side in order to prevent the movement of the person to be measured 5 from being restricted by the magnetic sensor. However, the magnetic sensor of the person to be measured 5 is arranged as in the first or fourth embodiment. If the magnetic sensor is arranged only on one side and the width dimension of the high-permeability sheet member 1 is larger than the shoulder width, even if the magnetic sensor is arranged above the high-permeability sheet member 1, the movement of the person to be measured 5 is limited so much. Not done.

In each of the above-mentioned embodiments, an example in which the deformation assisting member 2 is arranged below the high magnetic permeability sheet member 1 has been described, but the biological signal detecting device according to the present invention has such a structure. The shape of the bed 6 is not limited and may be omitted as appropriate.
May be used as the deformation assisting member. The same applies to the bed 6.

The object to be measured in the present invention is not limited to the person to be measured 5, that is, the human body, and may be an animal such as a dog or a cat.

[0085]

As described above, according to the present invention, when the measured object is placed on the deformable high magnetic permeability member, the fine movement of the measured object is transmitted to the high magnetic permeability member, and at that time, The magnetic permeability member is slightly deformed by a slight movement, and a change in static magnetic field (geomagnetism) due to the minute deformation of the high magnetic permeability member is detected and measured by a magnetic sensor arranged in the vicinity of the high magnetic permeability member.

As described above, since the object to be measured is only placed on the deformable high-permeability member, there is no such thing as an electrode to which a cord for restricting its movement is connected. In addition, there is an effect that it is not necessary to perform any operation on the object to be measured, and moreover, the object to be measured is hardly loaded.

As the high magnetic permeability member, iron-based, iron /
When an amorphous alloy such as a nickel-based or cobalt-based alloy is used, it has a high magnetic permeability and can be thinly formed into a sheet shape, which makes it easy to deform due to fine movement of the measured object, which changes the magnetic field distribution. Since it also becomes large, a large detection signal (biological signal) can be obtained from the magnetic sensor arranged in the vicinity thereof. In addition, since the high magnetic permeability member can be made thin, it is highly flexible, does not give an uncomfortable feeling to the object to be measured, and makes it difficult to sense the presence of the high magnetic permeability member.

When a high magnetic permeability member having a portion wider than the shoulder width of the measured body (measured person) is used, the movement of the measured body is allowed within the range of the high magnetic permeability member. ,
The burden on the object to be measured can be further reduced.

Further, when the deformation assisting member for assisting the deformation of the high magnetic permeability member is arranged below the high magnetic permeability member, the high magnetic permeability member is further deformed due to the fine movement of the object to be measured. Since this facilitates the change in the magnetic field distribution due to this deformation, a large detection signal can be obtained by the magnetic sensor disposed near the high magnetic permeability member.

If the magnetic sensor is arranged below the high-permeability member or the deformation assisting member, the magnetic sensor does not regulate the movement or position of the object to be measured. It is possible to further reduce the load on the object to be measured.

Further, since the magnetic flux easily passes through a substance having a high magnetic permeability, the magnetic flux due to the static magnetic field is concentrated near the peripheral portion of the sheet-shaped high magnetic permeability member. Therefore, in the vicinity of this peripheral portion, the magnetic field distribution due to the fine movement of the measured object changes greatly, and therefore, if the magnetic sensor is arranged there,
A large detection signal is obtained from the magnetic sensor, and the biological signal is detected more reliably.

Further, the influence of magnetism on the living body is still unknown, and application of a strong magnetic field to the living body (human body) for a long period of time may cause side effects, but geomagnetic field is a safe magnetic field existing in nature. If is used as a static magnetic field, there is no fear of giving side effects, and there is a great advantage in terms of safety.

Further, if the static magnetic field is due to the geomagnetism and a magnetic sensor is arranged in the vicinity of the peripheral edge of the high magnetic permeability member in at least one of the north and south directions of the sheet-shaped high magnetic permeability member, the magnetic flux due to the geomagnetism is directed in the north and south directions. The magnetic flux concentrates in the vicinity of the peripheral edge of the sheet-shaped high-permeability member in the north-south direction, so the change in magnetic flux (change in magnetic field distribution) due to the fine movement of the measured object in the peripheral edge is large. Therefore, a large detection signal can be obtained from the magnetic sensor arranged near the peripheral portion.

Further, for noise component removal, it is arranged at a position different from that of the magnetic sensor arranged near the high magnetic permeability member, for example, at a position which is not affected by the change of the static magnetic field due to the deformation of the high magnetic permeability member. If another magnetic sensor is provided and the differential signals of the two magnetic sensors are obtained, a part or almost all of the noise component due to the external magnetic field or the like can be removed, so that the influence of the external magnetic field or the like can be reduced, and thus, More accurate detection of the biological signal can be performed.

Further, both the magnetic sensor and the other magnetic sensor are arranged in the vicinity of the high magnetic permeability member, and one of these two magnetic sensors (for example, the other magnetic sensor) is changed by the deformation of the high magnetic permeability member. When the static magnetic field is arranged at a position where the change polarity of the static magnetic field is opposite to the change polarity of the static magnetic field at the arrangement position of the other of the two magnetic sensors (for example, the magnetic sensor),
Part or almost all of the noise component due to the external magnetic field can be removed, and the effective detection signal can be increased, so the so-called S / N ratio (signal-to-noise ratio) becomes high and the biological signal is more accurate. Can be detected.

Furthermore, if the magnetic sensor is of the flux gate type, its detection sensitivity is higher than that of other magnetic sensors such as Hall elements, so that even if the static magnetic field is a weak magnetic field such as the earth's magnetism, its change will occur. Can be reliably detected, and if the detection sensitivity is insufficient, the detection sensitivity can be increased by a simple method of increasing the number of turns of the secondary coil.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a biological signal detecting apparatus according to the present invention.

[Fig.2] Fluxgate type magnetic sensor (FGS)
It is a block diagram which shows an example of a structure of.

FIG. 3 is a block diagram showing an example of a processing circuit for analog-processing the fine movement obtained by the first magnetic sensor and the second magnetic sensor in the embodiment shown in FIG.

FIG. 4 is a signal waveform diagram showing a signal state of each part in the processing circuit shown in FIG.

5 is a block diagram showing an example of a processing circuit for digitally processing the fine movement obtained by the first magnetic sensor and the second magnetic sensor in the embodiment shown in FIG. 1. FIG.

6 is a signal waveform diagram showing a signal state of each part in the processing circuit shown in FIG.

FIG. 7 is a waveform diagram showing a slight movement of a human body obtained by the embodiment shown in FIG.

FIG. 8 is a configuration diagram showing a second embodiment of the biological signal detecting device according to the present invention.

FIG. 9 is a configuration diagram showing a third embodiment of the biological signal detecting apparatus according to the present invention.

FIG. 10 is a configuration diagram showing a fourth embodiment of the biological signal detecting device according to the present invention.

[Explanation of symbols] 1 High-permeability sheet member (high-permeability member) 2 Deformation auxiliary member 3 First magnetic sensor 4 Second magnetic sensor (other magnetic sensor) 5 Person to be measured (body to be measured) 6 beds 7, 8 amplifier circuit 9,10 Detection circuit 11, 12 Integration circuit 13, 14 Low-pass filter 15 Resistor isolation circuit 16 FGS drive circuit 17 Clock generation circuit 18 Subtraction circuit 19, 20 Analog-to-Digital (AD) converter 21 Microcomputer 22 holes

Front Page Continuation (56) References JP 62-64338 (JP, A) JP 1-39527 (JP, A) JP 62-155833 (JP, A) JP 1-22036 (JP) , A) JP-A-60-122541 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) A61B 5/11 A61B 5/00 A61B 5/02 A61B 5/05

Claims (12)

(57) [Claims] 1. A deformable high-permeability member, such as a sheet, which is placed in a static magnetic field and on which an object to be measured can be placed and which is made of an amorphous alloy such as an iron-based, iron / nickel-based, or cobalt-based alloy, It is arranged in the vicinity of the high-permeability member, and the deformation of the high-permeability member due to the fine movement of the object to be measured changes the static magnetic field.
And a detectable magnetic sensor as reduction, the magnetic sensor
A biological signal detection device, wherein a biological signal is obtained from the detection output of the service . Wherein disposed in a static magnetic field, the high permeability member is deformable such can be placed sheet the object to be measured, the high
The deformation of the high magnetic permeability member, which is arranged below the magnetic permeability member.
A deformation assisting member for assisting, and a magnetic sensor that is arranged in the vicinity of the high magnetic permeability member and is capable of detecting deformation of the high magnetic permeability member due to fine movement of the measured object as a change in static magnetic field , Obtains a biological signal from the detection output of the magnetic sensor
Biological signal detecting apparatus characterized by that. Below the wherein the high permeability material, the biological signal detection apparatus according to claim 1, characterized in that a deformation assisting member for assisting the deformation of the high permeability member. 4. The high magnetic permeability member is iron-based, iron / nickel
The biological signal detection device according to claim 2 , wherein the biological signal detection device is an amorphous alloy such as a ruthenium-based or cobalt-based alloy . 5. The magnetic sensor of the high magnetic permeability member.
It is arranged on the lower side, or
2. The biological signal detection device according to item 2 . 6. The magnetic sensor is provided in the deformation assisting member.
The biological signal detecting device according to claim 2 , wherein the biological signal detecting device is arranged on a lower side . 7. The high magnetic permeability member is a sheet,
The magnetic sensor is a peripheral portion of the sheet-shaped high magnetic permeability member.
It is arranged in the vicinity, or claim 1 or
2. The biological signal detection device according to item 2 . 8. The static magnetic field is terrestrial magnetism, and the magnetic sensor comprises a small magnetic field in the north-south direction of the sheet-shaped high magnetic permeability member.
At least one side of the sheet-shaped high-permeability member near the periphery
The biological signal detecting device according to claim 7 , wherein the biological signal detecting device is arranged near the biological signal detecting device. 9. The magnetic sensor is arranged at a position different from that of the magnetic sensor.
Further equipped with another magnetic sensor for removing noise components
And obtaining a differential detection signal of the two magnetic sensors
And removing the noise component by claim 1
9. The biological signal detection device according to any one of 8 to 8 . 10. The other magnetic sensor is the high magnetic permeability.
At a position that is not affected by changes in the static magnetic field due to member deformation
The biological signal detection device according to claim 9, wherein the biological signal detection device is arranged . 11. The other magnetic sensor is the high magnetic permeability part.
Placed near the material, and one of the two magnetic sensors
One is the change polarity of the static magnetic field due to the deformation of the high permeability member.
Is a change in the arrangement position of the other of the two magnetic sensors
The biological signal detection device according to claim 9 , wherein the biological signal detection device is arranged at a position opposite to the polarity . 12. The magnetic sensor is a flux gate.
The method according to claim 1 or 11, characterized in that
The biological signal detection device according to any one of claims.