JP5807781B2 - Biological signal detector - Google Patents

Description

  The present invention relates to a biological signal detector that detects a biological signal of a person or an animal.

  Conventionally, a biological signal detection body used for a biological information detection mat or the like for measuring a heart rate / respiration rate of a human body, measuring a heart rate / respiration waveform, detecting a human body, and measuring a body temperature includes a detection element and a protective material for protecting the detection element. In order to improve the detection accuracy, there are sensors that have an uneven surface (see Patent Document 1).

  Further, as a human body detection sheet, a structure in which a plurality of detection pieces made of a polymer piezoelectric film are laid in parallel on a core made of soft rubber or the like (see Patent Document 2), There is a sensor (see Patent Document 3) that includes a sensor that measures displacement using a flat material that outputs a signal by pressure and that detects the displacement by incorporating the flat material.

Japanese Patent No. 4029177 JP 2006-247329 A JP 2010-51686 A

In the biometric information detection mat of Patent Document 1, deformation of the uneven surface of the detection element is repeated after a long period of use, and the detection sensitivity tends to decrease.
In the human body detection sheet of Patent Document 2, since the detection piece is arranged on a core material such as soft rubber, deformation of the detection piece (polymer piezoelectric film) is suppressed, and the voltage output value with respect to pressure becomes small. .
Moreover, in the human body information detection sensor of patent document 3, since the planar raw material woven in the sensor deform | transforms by long-term use, detection sensitivity tends to fall.

  An object of the present invention is to provide a biological signal detector capable of obtaining high detection sensitivity and maintaining the detection sensitivity well over a long period of time.

A first characteristic configuration of the biological signal detector of the present invention is a support body in which a first recess is formed, and is arranged on the support body in a state of protruding to at least a part of the first recess. A pressure sensor that detects an external force by bending and receiving an external force, a flexible material that is attached to the support body while covering the first recess and the pressure sensor, and is supported by the support body. A displacement transmission body connected to an overhang portion of the pressure sensor, and a part of the displacement transmission body is bonded to the upper surface of the pressure sensor .

  As in this configuration, the pressure sensor is placed on the support in a state of overhanging at least a part of the first recess formed in the support, and this overhang is subjected to an external force to bend and deform to detect the external force. If it is the structure which does, when the flexible material which covers the upper part of a pressure sensor receives a load, the overhang | projection part of a pressure sensor can deform | transform into the inward side of a 1st recessed part. Thus, increasing the amount of deformation of the overhanging portion increases the voltage output value, making it easier to detect a biological signal.

Further, as in this configuration, the displacement transmission body is supported by the support body, and a part of the displacement transmission body is connected to the overhanging portion of the pressure sensor, so that the living body to be detected can be detected from the displacement transmission body to the overhanging portion of the pressure sensor. A signal is transmitted, and a wide detection area of a biological signal can be secured.

Further, as in this configuration, when a part of the displacement transmitting body is bonded to the overhanging portion of the pressure sensor, a biological signal input to the displacement transmitting body is transmitted to the overhanging portion of the pressure sensor. Become. In particular, when the displacement transmitting body is bonded to the upper surface of the overhanging portion of the pressure sensor, the displacement transmitting body that has received a biological signal pushes the overhanging portion of the pressure sensor. A compressive force acts on the adhesive portion of the sensor with the protruding portion. Therefore, compared with a configuration in which a tensile force acts, the bonded portion between the displacement transmission body and the overhang portion of the pressure sensor is less likely to be damaged.

The second characteristic configuration of the biological signal detector of the present invention is that a second recess is formed below at least a part of the displacement transmission body.

  If the second recess is formed below at least a part of the displacement transmission body as in this configuration, the displacement transmission body can be deformed so as to enter the inner portion of the second recess, and the displacement transmission body is displaced. This improves the detection sensitivity of the biological signal detector.

The 3rd characteristic structure of the biological signal detection body of this invention exists in the point by which the said 1st recessed part and the said 2nd recessed part are formed in the same recessed part.

  If the first concave portion and the second concave portion are formed by the same concave portion as in the present configuration, the configuration of the support in the biological signal detector becomes simple, which facilitates processing and the like. A biological signal detector can be obtained.

The figure which shows the use condition of a biosignal detection body Perspective view of main part of biological signal detector Main part plan view of a biological signal detector Longitudinal sectional view of main part of biological signal detector Main part plan view of comparative example Longitudinal section of the main part

  Hereinafter, a biological signal detector 100 according to the present invention will be described with reference to the drawings.

  As shown in FIG. 1, for example, a plurality of biological signal detectors 100 are mounted in a mattress M (or arranged under the mattress M, a rug, etc.), and in a lying state, the biological signal detector 100 is subject to body displacement due to heartbeat, breathing, and the like. The voltage signal is detected as a biological signal such as a human body.

[First embodiment]
As shown in FIGS. 2 to 4, the biological signal detector 100 includes a sheet-like intermediate member 2, 3, 5, a pressure sensor 4, and a plate between a sheet-like lower surface member 1 and an upper surface member 6. The displacement transmission body 7 is provided. Here, in this embodiment, the lower surface material 1, the first intermediate material 2, and the second intermediate material 3 are configured as supports, and the third intermediate material 5 and the upper surface material 6 are configured of a flexible material.

  A first intermediate material 2 is installed on the lower surface material 1, and a second intermediate material 3 and a pressure sensor 4 are installed on the first intermediate material 2. The second intermediate member 3 includes a rectangular space, and the first recess 8 is formed by this space and the upper surface of the first intermediate member 2. The pressure sensor 4 is disposed on the first intermediate member 2 so as to protrude from at least a part of the first recess 8. The pressure sensor 4 detects the external force when the overhanging portion 10 protruding to the first concave portion 8 receives an external force and bends and deforms. The main body 11 of the pressure sensor 4 is installed in a notch 9 of the second intermediate material 3 formed continuously with the first recess 8.

  The pressure sensor 4 is a piezoelectric film sensor or the like. When the pressure sensor 4 is a piezoelectric film sensor, the overhang portion 10 becomes a piezoelectric film portion. As the piezoelectric film, a polymer piezoelectric material such as polyvinylidene fluoride (PVDF) is used. Piezoelectric films do not respond to static pressure, but respond to changes in pressure over time. Therefore, it is possible to obtain a voltage signal for a change in the body due to heartbeat or respiration regardless of the weight of the detection target.

  A plate-like displacement transmission body 7 is arranged on the second intermediate member 3 with a part protruding from the first recess 8. The displacement transmission body 7 is supported by the second intermediate member 3, and a part thereof is connected to the overhanging portion 10 of the pressure sensor 4, and the displacement transmission body 7 is disposed on the upper surface of the end portion 10 a of the overhanging portion 10. The end 7a is overlapped and bonded.

  The displacement transmission body 7 is supported by the second intermediate member 3 as a support, and a part of the displacement transmission body 7 is connected to the overhanging portion 10 of the pressure sensor 4, so that the overhanging portion of the pressure sensor 4 is also connected to the displacement transmission body 7. The biosignal to be detected is transmitted to 10 and a wide detection area of the biosignal can be secured.

  The second intermediate member 3 has a space below the end 7 a of the displacement transmission body 7, and a second recess 12 is formed by this space and the upper surface of the first intermediate member 2. If the second recessed portion 12 is formed below at least a part of the displacement transmitting body 7, the displacement transmitting body 7 can be deformed so as to enter the inner portion of the second recessed portion 12, and the displacement transmitting body 7 is displaced. It becomes easy and the detection sensitivity of the biological signal detection body 100 improves.

  In the present embodiment, the first recess 8 and the second recess 12 are formed by the same recess. If the first concave portion 8 and the second concave portion 12 are formed of the same concave portion, the structure of the support (the first intermediate material 2 and the second intermediate material 3) in the biological signal detector 100 becomes simple, and the processing is performed. And the like, and a rational biological signal detector can be obtained.

  Further, when a part of the displacement transmitting body 7 is bonded to the overhanging portion 10 of the pressure sensor 4, a biological signal input to the displacement transmitting body 7 is transmitted to the overhanging portion 10 of the pressure sensor 4. Become. In particular, when the displacement transmission body 7 is bonded to the upper surface of the overhanging portion 10 of the pressure sensor 4, the displacement transmission body 7 that has received a biological signal pushes the overhanging portion 10 of the pressure sensor 4, In this case, a compressive force is applied to the bonding portion (7a, 10a) between the displacement transmitting body 7 and the overhanging portion 10 of the pressure sensor 4. Therefore, compared with a configuration in which a tensile force acts, the bonded portion between the displacement transmitting body 7 and the overhanging portion 10 of the pressure sensor 4 is less likely to be damaged.

  A third intermediate material 5 is disposed on the second intermediate material 3. The third intermediate member 5 is notched at a portion that interferes with the main body 11 of the pressure sensor 4, and the displacement transmitter 7 is sandwiched between the second intermediate member 3 and the third intermediate member 5.

  The upper surface material 6 is disposed on the third intermediate material 5, and the end surfaces of the lower surface material 1 and the upper surface material 6 are overlapped and sealed, thereby generating a biological signal detection body (biological signal detection mat) 100. .

  The pressure sensor 4 is disposed on the support (first intermediate material 2) in a state of overhanging at least a part of the first recess 8 formed in the support (first intermediate material 2, second intermediate material 3). If the overhanging portion 10 receives an external force and bends and deforms to detect the external force, the flexible material (the third intermediate member 5 and the upper surface member 6) that covers the upper portion of the pressure sensor 4 receives a load. At this time, the overhanging portion 10 of the pressure sensor 4 can be deformed inward of the first recess 8. Thus, increasing the amount of deformation of the overhanging portion 10 increases the voltage output value, making it easier to detect a biological signal.

[Example]
As shown in FIGS. 2 to 4, the bottom material 1 and the top material 6 are flexible materials, the intermediate materials 2, 3 and 5 are rubber sponges, the pressure sensor 4 is a piezoelectric film sensor (the piezoelectric material is polyvinylidene fluoride), A resin plate was used as each of the displacement transmission bodies 7 to generate a biological signal detector (biological signal detection mat) 100.

  A resin plate (displacement transmission body) 7 is prepared by superimposing and pasting the piezoelectric film part (overhanging part) 10 of the piezoelectric film sensor (pressure sensor) 4, and a sheet-like rubber sponge ( First intermediate material, second intermediate material) 2 and 3 are installed.

  When the piezoelectric film sensor 4 is installed on the rubber sponge 2 and the rubber sponge 3 is further installed, there is a space below the piezoelectric film portion 10 and the periphery of the portion where the piezoelectric film sensor 4 and the rubber sponge 3 interfere with each other. Rubber sponge 3 is cut away so that it can be done. Thus, the first recess 8 and the notch 9 that is continuous with the first recess 8 and accommodates the main body 11 of the piezoelectric film sensor 4 are formed.

  The end portion 7a of the resin plate 7 is superposed on and bonded to the upper surface of the end portion 10a of the piezoelectric film portion 10. A rubber sponge (third intermediate material) 5 is installed on the rubber sponge 3. The rubber sponge 5 is cut out at a portion that interferes with the main body 11 of the piezoelectric film sensor 4. The resin plate 7 is sandwiched between the rubber sponge 3 and the rubber sponge 5.

  An upper surface material 6 is installed on the rubber sponge 5, and the end surfaces of the lower surface material 1 and the upper surface material 6 are overlapped and sealed. Thus, a biological signal detection mat 100 that is a biological signal detector was generated.

[Comparative example]
5 and 6 show the configuration of the biological signal detection mat of the comparative example. Rubber sponges (first intermediate material and second intermediate material) 2 and 3 are installed on the lower surface material 1. The rubber sponge 3 is cut out so that the main body portion 11 of the piezoelectric film sensor (pressure sensor) 4 is accommodated, and the piezoelectric film portion 10 is disposed on the upper surface of the rubber sponge (second intermediate material) 3. The rubber sponge (third intermediate material) 5 is installed on the rubber sponge (second intermediate material) 3. The rubber sponge 5 has a notch formed in a portion that interferes with the main body 11 of the piezoelectric film sensor 4. An upper surface material 6 is installed on a rubber sponge (third intermediate material) 5, and the end surfaces of the lower surface material 1 and the upper surface material 6 are overlapped and sealed. The lower surface material 1, the upper surface material 6, the intermediate materials 2, 3, 5, and the pressure sensor 4 were the same as those in the example.

[Evaluation results]
For each biological signal detection mat of the example and the comparative example, the signal S and the noise N were measured under the following conditions, and the S / N ratio was calculated.

  The measurement environment was such that each biological signal detection mat was placed between the tatami mat and the mattress, and below the chest when the subject was lying on his back.

  As the measurement conditions, the noise N was measured in a state where the subject was not on the mattress under the measurement environment described above. Next, the signal S was measured in a state where the subject was lying on his back so as not to move his body on the mattress, and the S / N ratio was calculated. Such measurement was repeated three times. The measurement results are shown in Table 1 below. In Table 1, the average value of S / N is also calculated.

[Table 1]

  As can be seen from Table 1, with respect to the noise N, the example was smaller than the comparative example, and for the signal S, the output of the example was about three times the output of the comparative example. Moreover, in the S / N ratio representing the sensitivity of the biological signal detector, the example improved about 4 times compared to the comparative example. From this, it can be understood that the detection sensitivity of the biological signal is improved by adopting the configuration of the embodiment in the biological signal detection mat.

[Other embodiments]
(1) In the above-described embodiment, the support is constituted by the lower surface material 1, the first intermediate material 2, and the second intermediate material 3, and the flexible material that covers the first recess 8 and the pressure sensor 4 is the third intermediate material. Although the example of the composite_body | complex comprised by 5 and the upper surface material 6 was shown, you may comprise a support body and a flexible material integrally, respectively.

(2) The lower surface material 1, the upper surface material 6, the intermediate materials 2, 3, 5 and the displacement transmission body 7 are not limited to specific materials and thicknesses, and are appropriately selected so as to obtain an optimum evaluation result. To do. Moreover, the shape of the displacement transmission body 7 is not limited to the shape shown in the embodiment, and is selected so as to obtain suitability and an optimum evaluation result. Further, the method and the position of attaching the displacement transmitting body 7 to the overhanging portion 10 of the pressure sensor 4 are not limited to those shown in the embodiments, and are appropriately selected so as to obtain an optimum evaluation result. .

(3) In the above embodiment, the example in which the displacement transmission body 7 and the overhanging portion 10 of the pressure sensor 4 are bonded is shown. However, the displacement transmission body 7 and the overhanging portion 10 of the pressure sensor 4 are integrated. It may be configured.

(4) In the above embodiment, the example in which the displacement transmission body 7 is bonded to the upper surface of the overhanging portion 10 of the pressure sensor 4 is shown. However, the displacement transmission body 7 is the lower surface of the overhanging portion 10 of the pressure sensor 4. It may be adhered to. However, since the displacement transmission body 7 that has received the biological signal moves away from the overhanging portion 10 of the pressure sensor 4, the adhesive strength between the displacement transmission body 7 and the overhanging portion 10 of the pressure sensor 4 is increased. Need to increase.

(5) In the above embodiment, the example in which the second intermediate material 3 is cut away so as to create a space around the lower surface of the overhanging portion 10 of the pressure sensor 4 and the periphery thereof is shown. The third intermediate member 5 may be cut out so that a space is formed on the upper surface and the periphery thereof. Alternatively, the main body 11 of the pressure sensor 4 may be accommodated only by the cutout portion 9 of the second intermediate material 3, and the third intermediate material 5 may be configured without forming a cutout.

(6) In the above-described embodiment, the example in which the displacement transmission body 7 and the pressure sensor 4 are bonded to each other has been shown. However, the displacement transmission body 7 may be configured to use the protruding portion 10 of the pressure sensor 4.

  The biological signal detector according to the present invention is not limited to a human body and can be widely used as a biological signal detector for animals such as pets.

1 Bottom material (support)
2 First intermediate material (support)
3 Second intermediate material (support)
4 Pressure sensor (piezoelectric film sensor)
5 Third intermediate material (flexible material)
6 Top material (flexible material)
7 Displacement transmission body (resin plate)
8 1st recessed part 10 Overhang | projection part (piezoelectric film part)
11 Main Body 12 Second Concave 100 Biosignal Detection Body (Biosignal Detection Mat)

Claims (3)

A support formed with a first recess;
A pressure sensor that is disposed on the support in a state of projecting to at least a part of the first recess, and that the projecting portion receives an external force to bend and deform to detect the external force;
A flexible material attached to the support while covering the first recess and the pressure sensor;
A displacement transmission body supported by the support body and partly connected to an overhang portion of the pressure sensor ,
A biological signal detection body in which a part of the displacement transmission body is bonded to the upper surface of the pressure sensor . Biological signal detector according to claim 1, wherein are second recess is formed on at least a portion of the lower of the displacement transmission member. The biological signal detector according to claim 2, wherein the first recess and the second recess are formed of the same recess.

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