JP3578665B2 - Biological information detection sensor - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a biological information detection sensor that measures biological information by applying vibration to the living body from the surface of the living body and detecting and analyzing the vibration propagated in the living body, and in particular, to a sensor that enables highly accurate measurement. It is.
[0002]
[Prior art]
As a sensor for measuring biological information by applying vibration to the living body from the surface of the living body and detecting and analyzing the vibration propagated in the living body, a sensor described in Japanese Patent Application Laid-Open No. 9-506024 is known. Have been. This sensor is composed of an exciter for applying vibration to a living body and a vibration detector for detecting the transmitted vibration.
[0003]
The device disclosed in Japanese Patent Publication No. 9-506024 discloses a device in which an exciter is arranged on a patient's artery, a vibration wave is induced in arterial blood, and a vibration detector is arranged on the artery and propagated in the artery. By detecting and analyzing the generated vibration wave, the biological information of the patient is continuously measured.
[0004]
[Problems to be solved by the invention]
However, Japanese Patent Application Laid-Open No. 9-506024 describes that an exciter and a vibration detector are independently installed on a subject. In an apparatus for measuring biological information by detecting and analyzing a vibration transmitted through a living body, the positional relationship between the exciter and the vibration detector is important, and is described in Japanese Patent Publication No. 9-506024. With the method of installing the exciter and the vibration detector, there is a problem that it is difficult to determine stable positional information between the exciter and the vibration detector, so that stable biological information cannot be measured.
[0005]
The present invention solves such a conventional problem, and can stably set the positional relationship between an exciter and a vibration detector, and can measure stable biological information. It is intended to provide a detection sensor.
[0006]
[Means for Solving the Problems]
Therefore, in the present invention, an exciter that applies vibration to a part of a living body, a vibration detector that detects vibration transmitted through the living body, and a connection unit that determines a distance between the exciter and the vibration detector A biological information detection sensor is configured, and a part or all of the connecting portion is formed of a material that attenuates the vibration induced by the exciter so that the vibration does not propagate through the connecting portion and reach the vibration detector.
[0007]
For this reason, the positional relationship between the exciter and the vibration detector that determines the detection ability is set stably by the connecting portion, and the vibration that propagates through this connecting portion and causes a decrease in measurement accuracy is attenuated. Therefore, stable biological information can be measured.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
The invention according to claim 1 of the present invention provides an exciter that applies vibration to a part of a living body, a vibration detector that detects vibration transmitted through the living body, and an exciter and a vibration detector that are located on a straight line . A connection portion for determining a distance , wherein a part or all of the connection portion does not reach the vibration detector because vibration induced by the exciter propagates through the connection portion Since the connection part attenuates the vibration, the vibration detector can detect only the vibration that has propagated through the living body, thus improving the accuracy of measuring biological information. Have.
[0009]
The invention according to claim 2 uses, as the material, a material having elasticity capable of arbitrarily changing the distance between the exciter and the vibration detector, and the connecting portion expands and contracts. Accordingly, the distance between the exciter and the vibration detector can be arbitrarily changed, so that the degree of freedom of attachment to the living body is improved.
[0010]
According to the third aspect of the present invention, a plurality of exciters, vibration detectors, and connection portions are provided, respectively, so that a plurality of measurement sites and / or a wide range of measurement can be performed. Is improved.
According to a fourth aspect of the present invention, a portion of the connecting portion between the exciter and the vibration detector is made of a different material from the other portions. The insertion of the material acts to reflect / attenuate the vibration at the connection surface.
[0011]
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0012]
FIG. 1 is a perspective view showing a biological information detection sensor according to a first embodiment of the present invention. In FIG. 1, the biological information detection sensor includes an exciter 1 for inducing vibration in a living body, and a vibration transmitted through the living body. Detector 2, a connection 3 connecting the exciter 1 and the vibration detector 2, and a vibration induced by the exciter 1 is prevented from propagating through the connection 3 and reaching the vibration detector 2. A vibration attenuator 4 for attenuating vibration, an exciter signal propagation cable 6 for transmitting a signal for vibrating the exciter 1, and a detection signal propagation cable 7 for transmitting a biological information signal detected by the vibration detector 2. Have.
[0013]
The exciter signal propagation cable 6 propagates a signal for vibrating the exciter 1 output from a signal processing device (not shown) for processing a biological information signal, and the detection signal propagation cable 7 The detected biological information signal is propagated to the signal processing device.
[0014]
FIG. 2 shows a state where the living body information detection sensor is mounted on a living body (here, an arm). An example in which this biological information detection sensor is used for a non-invasive continuous sphygmomanometer will be described with reference to FIG.
[0015]
The exciter 1 is an oscillation source that oscillates at an arbitrary frequency and amplitude that is most effective for the subject. The exciter 1 vibrates the artery 22 in the living body (the arm 21 in this case) from the body surface, and the vibration detector 2 , And converts the vibration provided by the exciter 1 and propagated on the artery into an electric signal. From this electric signal, a continuous blood pressure is calculated by a method similar to the method described in Japanese Patent Publication No. 9-506024.
[0016]
When blood pressure is continuously measured non-invasively by the above method, it is known that the state of attachment of the exciter 1 and the vibration detector 2 to the living body greatly affects the blood pressure detection ability.
[0017]
Therefore, in the present invention, as shown in FIG. 1, a configuration is provided in which a connection portion 3 for determining a positional relationship between the exciter 1 and the vibration detector 2 and a vibration damping portion 4 are provided.
[0018]
In FIG. 2, “vibration waveform 31 propagating through artery” is a waveform schematically representing a vibration waveform when vibration induced by exciter 1 propagates through artery 22, and “vibration waveform propagating through connection portion”. The “waveform 32” is a waveform schematically representing a vibration waveform when the vibration induced by the exciter 1 propagates through the connection portion 3. The “vibration waveform 33 attenuated by the vibration attenuator” is a waveform schematically representing the vibration waveform of the vibration waveform 32 propagating through the connection portion 3 attenuated by the vibration attenuator 4.
[0019]
When the connecting portion 3 is connected to determine the positional relationship between the exciter 1 and the vibration detector 2, the vibration oscillated by the exciter 1 causes not only the artery but also the connecting portion 3 to vibrate. The vibration (the vibration waveform 32 propagating through the connection) propagates through the connection 3 and reaches the vibration detector 2.
[0020]
The phase of the vibration propagated through the artery 22 changes in accordance with the change in blood pressure, and the phase of the vibration propagated through the connection 3 does not change. Therefore, the artery is detected by performing phase detection on the vibration detected by the vibration detector 2. It is possible to identify whether the vibration has propagated or has propagated through the connection. At this time, since both the vibration transmitted through the artery and the vibration transmitted through the connection are small signals, in order to improve the measurement accuracy, the vibration oscillated by the exciter 1 is detected by the vibration detector via the connection 3. The vibration damper 4 is connected to the connection portion 3 so as not to propagate to the connection portion 2.
[0021]
The vibration attenuator 4 is made of a material that attenuates vibration of several hundred Hz to several kHz, which is the most suitable vibration frequency described in Japanese Patent Application Laid-Open No. 9-506024. One example of a suitable material is rubber. Rubber also has elasticity, and also has the effect of increasing the degree of freedom of mounting when the biological information sensor is mounted on a living body.
[0022]
As a material of the vibration attenuator 4, not only rubber but also scientific fibers such as nylon, vinyl and the like can be used.
[0023]
Further, in order to attenuate the vibration, the connecting portion 3 connecting the exciter 1 and the vibration detector 2 is not a uniform material, and the vibration is reflected / attenuated at the connecting surface by inserting another material. Therefore, the vibration attenuator 4 can have the effect of attenuating the vibration simply by being inserted regardless of the material.
[0024]
In addition, the number of vibration dampers 4 to be inserted is not limited to one, and a plurality of vibration dampers 4 can be inserted. In FIG. Installation is also possible.
[0025]
As described above, the biological information detection sensor of this embodiment can stably attach to the living body while maintaining the distance between the exciter 1 and the vibration detector 2 by having the connection portion 3. In addition, it is possible to prevent the detection ability from lowering due to body movement. In addition, by having the vibration damping unit 4 for attenuating the vibration transmitted through the connection unit 3, the vibration transmitted from the exciter to the vibration detector, which causes a decrease in measurement accuracy, is attenuated and propagates through the living body. Only vibration can be observed. As a result, the accuracy of the biological information measurement is improved.
[0026]
In addition, when the vibration damping unit 4 is made of an elastic material, the distance between the exciter and the vibration detector can be changed arbitrarily, so that the degree of freedom of attachment to the living body increases, Measurement stability can be improved.
[0027]
Next, as a second embodiment of the present invention, a case where a plurality of biological information detection sensors are used will be described with reference to FIG.
[0028]
FIG. 3 shows a case in which two biological information detection sensors are mounted on the arm 21. Each of the biological information detection sensors includes an exciter 1, a vibration detector 2, and a connection unit 3, as in the first embodiment. , A vibration attenuator 4, an exciter signal propagation cable 6, and a detection signal propagation cable 7.
[0029]
By having a plurality of biological information detection sensors in this way, it is possible to simultaneously measure distant parts of the subject, respectively, and by mounting a plurality of biological information detection sensors in close proximity, the same part can be spread over a wide area. Can be measured. Therefore, in the biological information detection sensor of this embodiment, for example, when blood pressure measurement is performed continuously without invasion, the blood pressure of both the left and right arms can be measured at the same time, and the reliability of patient monitoring can be improved.
[0030]
In addition, for example, when blood pressure measurement is performed continuously during non-invasion, the exciter 1 and the vibration detector 2 must be mounted on an artery, but the artery cannot be seen from the skin surface, so that mounting may be difficult. . In such a case, if a plurality of biological information detection sensors are mounted close to each other, the sensors will be mounted over a wide range, and the accuracy of biological information measurement can be improved.
[0031]
【The invention's effect】
As is clear from the above description, the biological information detection sensor of the present invention provides a vibration damping portion made of a material for damping vibration at the connection between the exciter and the vibration detector, which causes a decrease in measurement accuracy. Since the vibration transmitted from the exciter to the vibration detector through the connection portion is attenuated, the device can be stably mounted on the living body, and the accuracy of the biological information measurement can be improved.
[0032]
Further, by configuring the vibration attenuator with a stretchable material, the degree of freedom of attachment to a living body can be improved.
[0033]
In addition, by having a plurality of biological information detection sensors including an exciter, a vibration detector, a connection unit, and the like, it becomes possible to measure biological information of a plurality of parts or a wide area of the subject.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a biological information detection sensor according to a first embodiment of the present invention;
FIG. 2 is a diagram showing a configuration when a biological information detection sensor according to the first embodiment of the present invention is mounted on an arm;
FIG. 3 is a diagram illustrating a configuration of a plurality of biological information detection sensors according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Exciter 2 Vibration detector 3 Connection part 4 Vibration attenuator 6 Exciter signal propagation cable 7 Detection signal propagation cable 21 Arm 22 Artery 31 Vibration waveform propagating in artery 32 Vibration waveform propagating in connection part 33 Attenuated by vibration attenuator Vibration waveform

Claims (4)

An exciter that applies vibration to a part of a living body, a vibration detector that detects vibration transmitted through the living body, and a connection unit that determines a distance between the exciter and the vibration detector located on a straight line. A biological information detection sensor provided, wherein at least a part of the connection portion is formed of a material that attenuates the vibration induced by the exciter so that the vibration does not propagate to the connection portion and reach the vibration detector. A biological information detection sensor. The biological information detection sensor according to claim 1, wherein the material has elasticity so that a distance between the exciter and the vibration detector can be arbitrarily changed. The biological information detection sensor according to claim 1, further comprising a plurality of the exciters, the vibration detector, and the connection unit. The biological information according to any one of claims 1 to 3, wherein a part of the connection part between the exciter and the vibration detector is made of a material different from other parts. Detection sensor.

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