JP3191031B2 - Multi sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-sensor for detecting a plurality of types of biological information by being attached to the skin of a living body.

[0002]

2. Description of the Related Art Conventionally, measurement of pressure pulse waves and respiration in blood vessels of a living body has been performed by various methods. For example, in order to analyze a pressure pulse wave obtained non-invasively from the body surface, it must be measured simultaneously with an electrocardiogram. In this case, an electrocardiogram electrode is attached to the living body, and a piezoelectric transducer that converts pressure changes into an electric signal or a pressure transducer such as a gauge is attached on the arterial blood vessel for the purpose of recording pressure pulse waves and the like. Must. At this time, the pressure transducer is often mounted on the left or right common carotid or radial artery. In addition, when detecting a pressure pulse wave on the common carotid artery, a device for externally pressing the pressure transducer onto the artery is required.

On the other hand, when measuring respiratory movement which is important for monitoring the function of a living body with an ICU or the like, a two-electrode method or a four-electrode method is used.
Impedance method such as electrode method, belt type respiratory pickup that detects resistance change of electrolyte in tube that expands and contracts with chest movement, and temperature change due to air flow during breathing when worn on the nose and measurement A thermistor-type respiratory pickup is used.

[0004]

However, when a pressure transducer is mounted on a common carotid artery to measure a pressure pulse wave, the subject must be lying on a bed or the like at rest. When detecting a pressure pulse wave on the radial artery, for example, when mounting a pressure transducer using a piezoelectric element, it is necessary to wrap it around the wrist with a belt so that a certain pressure is applied on the measurement site. There is. In addition, when using such a transducer, it is necessary to find an appropriate mounting site, and training is required for the mounting. If the wrist is further moved, the position of the sensor shifts, and the pressure pulse wave cannot be detected. Therefore, even in this method, the measurement must be performed at rest, and it is very difficult to perform the measurement during daily activities. Furthermore, such transducers are large and expensive and cannot be disposable.

On the other hand, when an impedance pickup is used to measure respiratory movement, two or four electrodes are attached to the body surface, and the change in the resistance value of the living tissue between the electrodes due to thoracic movement. Is detected as a change in respiratory movement, and the distance between the two electrodes must be increased in order to detect a slight change between the electrodes as an impedance change.

In the case of using a belt-type pickup, a belt to which a tubular sensor is attached is wrapped around the chest, so that there is a sense of tying that a part of the body is occupied and tightened by the belt. For this reason, it is not widely used at present. In addition, since the belt tightening force has an appropriate range and the position easily shifts due to body movement or the like, it is necessary to keep quiet even when performing measurement using this method. It is expensive and not suitable for disposable use.

When a thermistor type pickup is used, the subject is discomforted because it is worn on the nose.
Also, because of its large power consumption, it is not suitable for a battery-driven wireless telemeter or the like.

Further, when simultaneously measuring the electrocardiogram and the pressure pulse wave or the electrocardiogram and the respiratory rate, at least two electrodes for the electrocardiogram must be attached to the body separately from the transducer for the pressure pulse wave or the respiration. As a result, there are drawbacks such as restraining the subject and causing discomfort and pain.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and a multi-sensor capable of simultaneously measuring an electric signal and a pressure of a living body with one element, and being small, lightweight, and inexpensive disposable. The purpose is to provide.

[0010]

According to one aspect of the present invention, there is provided a multi-sensor for detecting a plurality of types of biological information of a living body, which is mounted on a skin surface of the living body. An element formed of a conductive fiber in a plate shape, an adhesive layer provided on one end surface surrounding an outer periphery of the element, and a holder having a thickness substantially equal to the element, and both end faces of the holder And connected to both end faces of the element.
And a pair of terminals.

According to a second aspect of the present invention, of the pair of terminals, the terminal that contacts the skin surface of the living body has a shape that covers the entire end surface of the element, The contact surface of the element is covered with an insulating layer, and a superabsorbent material (supe) is placed between the outer periphery of the element and the inner periphery of the holder.
r absorbento polymer) such as carboxymethylcellulose, acrylic acid
lic acid) and polyvinyl alcohol (poly vinyl alc)
Ohol) is filled with conductive solid gel.

According to a third aspect of the present invention, a conductive solid gel is provided on each of the end surfaces of the element and the holder on the skin surface side of the living body.

The present invention according to claim 4 is characterized in that a second holder having a conductive solid gel or paste storage portion is provided on one end face of the element and the holder.

According to a fifth aspect of the present invention, the terminal on the skin side is formed in two layers with an insulating layer interposed therebetween.

[0015]

According to the first aspect of the present invention, the elements are formed of laminated conductive fibers, and the fibers are intricately entangled with each other. Increase. As a result, when a predetermined current is passed through the sensor, the DC resistance value decreases and appears as a voltage change at both ends. By measuring this voltage change, it is possible to know the change in the force received from the outside, and it is possible to detect a pressure pulse wave or respiratory fluctuation. The terminal on the skin surface side of the pair of terminals can be used as a terminal electrode for detecting a bioelectric signal such as an electrocardiogram.

The present invention according to the second and third aspects also has the same function as the first aspect of the present invention.

According to the fourth aspect of the present invention, since the conductive solid gel or paste storage portion is provided on the end surface of the multi-sensor element in contact with the skin surface, and the second holder is provided on the outer periphery thereof, The multi-sensor can be firmly fixed to the skin surface with a conductive solid gel or a paste together with the adhesive layer provided on the end surface of the second holder that comes into contact with the skin surface.

According to the fifth aspect of the present invention, the terminal on the side in contact with the skin surface has two layers with an insulating layer interposed therebetween, so that the terminal on the skin surface side detects a bioelectric signal such as an electrocardiogram. The change in the force received from the outside can be detected by the inner terminal and the terminal connected to the opposite end face of the element. That is, since the terminal for detecting the bioelectric signal is made independent from the other terminals, the bioelectric signal can be detected more stably.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the multi-sensor according to the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show the structure of a first embodiment of the present invention. In these figures, a cylindrically formed holding body 2 made of foam tape or the like is concentrically provided with a predetermined gap around an outer periphery of a columnar felt element 1 formed by coarsely laminating carbon fibers. Is placed on top. The axial heights of the element 1 and the holder 2 are substantially equal, and terminals 3 and 4 are connected to both end faces of the element 1 and the holder 2 on the respective diameters. One end face of the element 1 and the holder 2 is covered with a label 5 together with the terminal 3, and an adhesive layer 6 is provided on the other end face of the holder 2.

Next, the operation of the present embodiment will be described. In the element 1, since conductive carbon fibers are coarsely and intricately entangled with each other and formed in a felt shape, when a force is applied from the outside, the fibers become conductive. The number of contact points increases. As a result, terminals 3 and 4
When a predetermined current is passed through the element 1 through the element 1, the DC resistance value of the element 1 decreases and appears as a voltage change between the terminals 3 and 4. For example, when the element 1 has a thickness of 5 mm and a size of 10 mm in diameter, the DC resistance is 100Ω when no external force is applied, but when the external force is applied and the thickness is reduced by 0.5 mm, the DC resistance is 80Ω. Become. Although the resistance value of the carbon fiber varies depending on the firing temperature, the carbon fiber used for the element 1 of the present embodiment is easier to use if the resistance value is higher. As a material whose DC resistance value changes due to deformation due to external pressure, there is a conductive rubber or the like, but in order to cause the above-described voltage change, a large external force is required, It is unsuitable for detecting pressure pulse waves and respiratory fluctuations.

In the case of detecting a pressure pulse wave by the multi-sensor having the element 1 as described above, the sensor is attached to the skin at the position of an artery such as a wrist or neck via the adhesive layer 6 of the holder 2. Then, it is detected as a voltage fluctuation of the element 1. When respiratory fluctuations are detected, as shown in FIG.
1 is similarly attached to the chest and detected. Furthermore, when detecting a bioelectric signal such as an electrocardiogram, a normal living body electrode 52 and a sensor 51 are attached to predetermined positions on the skin surface, and detection is performed using the terminal 4.

FIG. 4 shows a multi-sensor 51 and an electrode 52 for a living body.
5 shows an example of wiring in the case of detecting respiratory fluctuations and electrocardiograms by using. The terminals 3 and 4 of the multi-sensor 51 are connected to an amplifier 54 via a bridge circuit 53, and detect a respiratory waveform based on the output of the amplifier 54. On the other hand, the terminal 4 of the multisensor 51 and the living body electrode 52 are connected to an amplifier 55, and an electrocardiogram waveform is detected based on an output of the amplifier 55. FIG. 5 shows an example of the measurement result.

According to the present embodiment, the bioelectric signal and the pressure signal can be simultaneously detected by one element 1, and the sensor can be made small, lightweight, inexpensive and disposable.

The shapes of the portions of the terminals 3 and 4 shown in FIGS. 1 to 3 which are connected to the element 1 are circular terminals 3 and 1 each having substantially the same diameter as the element 1 as shown in FIG. The terminal 4 may have a cross shape in which a part of the terminal 4 is in contact with the skin.

FIGS. 7 to 13 show the structure of another embodiment of the present invention. In these drawings, parts corresponding to those of the first embodiment shown in FIGS. 1 to 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

In the second embodiment of the present invention shown in FIG. 7, the moisture such as sweat generated from the skin during the measurement penetrates into the element 1 and the whole becomes conductive, making it impossible to detect the pressure. In order to avoid this, the portion of the terminal 4 connected to the element 1 is formed so as to cover the entire end face of the element 1, the contact surface of this portion with the skin surface is covered with an insulating layer 7, A conductive gel 8 is filled between the device and the outer periphery of the element 1 so that an electric signal of a living body is transmitted from the skin surface to the non-insulated side of the terminal 4 via the conductive solid gel 8.

In a third embodiment of the present invention shown in FIG. 8, a conductive solid gel layer 9 is provided on the end surfaces of the element 1 and the holder 2 on the skin surface side.

According to the second and third embodiments, the same effects as those of the first embodiment can be obtained.

The fourth embodiment of the present invention shown in FIGS. 9 to 11 has a conductive solid gel layer 11 covering the end face of the element 1 opposite to the side on which the label 5 is mounted, together with the terminal 4. The second holding body 12 is bonded to an end face on the same side of the first holding body 2, and an adhesive layer 13 is provided on an outer end face of the second holding body 12. In this embodiment, the terminal 4 does not protrude from the outer periphery of the element 1.

According to this embodiment, when the sensor is mounted on the skin surface, the element 1 is mounted on the skin surface via the conductive solid gel layer 11 and the second holder 12 is mounted on the skin surface via the adhesive layer 13. Therefore, the multi-sensor can be firmly fixed to the skin surface.

In the fifth embodiment of the present invention shown in FIGS. 12 and 13, the terminal 4 shown in FIGS.
It consists of. Terminal 4a connected to element 1 side
The surface is coated or plated with carbon,
The surface of the terminal 4b connected to the conductive solid gel layer 11 is coated or plated with Ag or AgCl. A film 21 as an insulating layer is provided between the terminals 4a and 4b.
It extends to the entire outer circumference between the two. Note that the conductive solid gel layer 11 in this embodiment does not need to be a solid gel because the film 21 is interposed therebetween, and prevents moisture from entering the element 1 side.
It may be an ordinary paste in which 1 or Kcl is mixed as an electrolyte (electrolytes). In that case, the center hole of the second holding body 12 functions as a paste storage section.

According to the present embodiment, it is possible to detect a change in the force received from the outside by the terminals 3 and 4a and to detect a biological signal such as an electrocardiogram by the terminal 4b. Therefore, the terminal 4b for detecting a biological signal is made independent from the other terminals 3 and 4a,
Stable detection can be performed.

In each of the above embodiments, the case where the element 1 is made of carbon fiber has been described. However, the element 1 may be made of another conductive fiber such as stainless steel fiber.

In each of the above embodiments, the label 5 may be omitted by making the shape of one end of the terminal 3 a shape that covers the entire surface of the holder 2.

[0036]

As described above, according to the multi-sensor of the present invention, terminals are connected to both end faces of the element constituted by the laminated conductive fibers. A bioelectric signal such as an electrocardiogram can be detected at the same time as a change in the biological pressure such as a fluctuation or a respiratory state, and a small, lightweight, inexpensive disposable device can be provided.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a configuration of a first embodiment of a multi-sensor according to the present invention.

FIG. 2 is a view taken in the direction of arrow A in FIG.

FIG. 3 is an exploded perspective view of FIG. 1;

FIG. 4 is a wiring diagram for signal detection according to the present invention.

FIG. 5 is a diagram showing an example of a measurement result according to FIG. 4;

FIG. 6 is an exploded perspective view showing a configuration of a modification of the first embodiment of the present invention.

FIG. 7 is an exploded perspective view showing the configuration of a second embodiment of the present invention.

FIG. 8 is an exploded perspective view showing the configuration of a third embodiment of the present invention.

FIG. 9 is a longitudinal sectional view showing the configuration of a fourth embodiment of the present invention.

FIG. 10 is a view taken in the direction of arrow A in FIG. 9;

FIG. 11 is an exploded perspective view of FIG. 9;

FIG. 12 is a longitudinal sectional view showing the configuration of a third embodiment of the present invention.

FIG. 13 is an enlarged view of a main part of FIG. 12;

[Explanation of symbols]

Reference Signs List 1 element 2 holder 3, 4 terminal 6, 13 adhesive layer 8 conductive solid gel 11 conductive solid gel layer 12 second holder 21 film (insulating layer)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) A61B 5/0408 A61B 5/0245

Claims (6)

(57) [Claims] 1. A multi-sensor mounted on a skin surface of a living body to detect a plurality of types of biological information of the living body,
An element formed in a plate shape by conductive fibers, a holder surrounding the element and having a thickness substantially equal to that of the element,
A multi-sensor comprising: a pair of terminals held on both end surfaces of the holder and electrically connected to both end surfaces of the element. 2. A terminal, of the pair of terminals, which is in contact with the skin surface side of the living body, has a shape which covers the entire surface of the element on the skin surface side, and a contact surface with the skin surface. 2. The multi-sensor according to claim 1, wherein a conductive solid gel is filled between an outer periphery of the element and an inner periphery of the holder. 3. 3. The multi-sensor according to claim 1, wherein a conductive solid gel layer is provided on end faces of the element and the holder on the skin surface side of the living body. 4. The multi-sensor according to claim 1, wherein a conductive solid gel layer and a second holder are provided on one end surface of the element and the holder. 5. The multi-sensor according to claim 1, wherein the terminal on the skin surface side is formed in two layers with an insulating layer interposed therebetween. 6. A multi-sensor mounted on a skin surface of a living body to detect a plurality of types of biological information of the living body,
An element formed of a conductive fiber in a plate shape, a holder surrounding the outer periphery of the element and having a thickness substantially equal to the element, and electrically connected to both end faces of the element held on both end faces of the holder. A pair of connected terminals, and a second holding body having an opening at a central portion is provided on the skin surface side of the terminal on the skin surface side of the pair of terminals. A terminal is formed in two layers sandwiching an insulating layer, one layer is electrically connected to the element, an intermediate insulating layer covers the entire surface of the holder and the element, and the other layer is the second holding layer. A multi-sensor, wherein a paste storage section is formed by being located at an opening of a body.