JP2012019847A - Biological signal detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biological signal detecting device capable of accurately detecting biological signals of a user's heart beating, body motion, respiration, etc. with simple configuration.SOLUTION: A rod-like vibration transmission pin 19 is fitted to a metal sheet 11 in a state of projecting in the radial direction of a piezoelectric element 2. Vertical force applied to the vibration transmission pin 19 can be transmitted to a piezoelectric body 12 of the piezoelectric element 2 and amplified by the elastic force of the vibration transmission pin 19, and electric charge converted according to the force applied to the piezoelectric body 12 can be made larger. The voltage change generated between the metal sheet 11 and a metal film 13 of the piezoelectric element 2 can be made larger. By signal-processing this voltage change in a signal processing circuit 17, the detection of biological signals based on the voltage change can be made further accurate.

Description

  The present invention relates to a biological signal detection apparatus for detecting a biological signal of at least one of a user's heartbeat, body movement, and respiration.

  Conventionally, as this type of biological signal detection device, as described in Patent Document 1 below, for example, a plurality of sensor pads that detect sound and pressure changes on the body surface caused by a user's biological activity are crossed across the living body. These sensors are connected to each sensor pad, and an output signal from the sensor is A / D converted by a plurality of A / D conversion circuits. The conversion result is added in real time by the addition means, the period is calculated by the period calculation means using the addition result, and the calculation period is directly output to the outside as data, and the heart rate / respiration rate / body movement per unit time is output. What is converted to numbers and fluctuations is known.

  As a method for extracting this type of biological signal, for example, as described in Patent Document 2 below, a time series signal (analog signal) such as a heartbeat respiratory biological signal is converted into a digital signal by an A / D conversion means. The two signal points having the same signal level value and the same change tendency (upward tendency or downward tendency) and the two closest points (in-phase point) on the time axis are detected by the in-phase point detection means. After detecting the distance of two in-phase points (in-phase point running distance) by the in-phase point running distance detecting means, the information detected by the in-phase point running distance detecting means is statistically processed by the statistical processing means, and the statistical processing means The information is analyzed by the occurrence count measurement means, the occurrence count of the same running distance is measured, the measurement result of the occurrence count measurement means is analyzed, and the running distance with the highest occurrence count is obtained by the main period output means. By outputting as the main cycle, it is known which detects a biological signal of the heart beat and respiration, and the like.

  Further, for example, as described in Patent Documents 3 to 5 below, as a piezoelectric sensor for detecting vibration acceleration generated from a user's body surface, a polymer piezoelectric material having a thin film shape and electrodes attached to both sides is used. Extracting only vibration components associated with body movements and outputting body movement signals as time-series data, large body movements associated with bed entry, getting out of bed, turning over, etc. It is known to classify whether there is a person or to determine the position of the human body by detecting minute vibrations propagating through the bedding generated by the activity of the person's heart or breathing.

Japanese Patent No. 4234481 Japanese Patent No. 412.2003 JP-A-8-080285 JP-A-7-204166 JP-A-6-165770

  However, according to the prior art according to Patent Document 1, the heart rate per unit time of the user is based on the change in air pressure in the sensor pad that detects the change in the sound and pressure on the body surface caused by the user's life activity. It can detect the heart rate, respiratory rate, body motion, fluctuation, etc. accurately, but it can accurately detect changes in the air pressure in these sensor pads. Therefore, it is necessary to improve the accuracy of the sensors that detect changes in air pressure in the sensor pads, and the output signals from these sensors are A / D converted and added in real time. The period must be calculated, and the calculated period must be output to the outside as it is. The configuration of the biological signal detection apparatus is complicated, and simplification is not easy.

  In the prior art according to Patent Document 2, a time series signal (analog signal) such as a heartbeat respiratory biological signal is converted into a digital signal, the signal level value is the same, the change tendency is the same, and the time axis The two points closest to each other (in-phase point) are detected, and the distance between these two in-phase points (in-phase point running distance) is detected and analyzed with statistical processing. By outputting the distance as the main period, biological signals such as heartbeat and respiration can be detected, so it is possible to accurately detect biological signals such as heartbeat and respiration. It is not easy to control for detecting the biological signal.

  Further, according to the prior arts disclosed in Patent Documents 3 to 5, only a vibration component associated with body motion is extracted by using a piezoelectric sensor in which a polymer piezoelectric material is formed into a thin film and electrodes are attached to both sides. As time-series data, or whether there is a large body movement associated with entering the bed, getting out of bed, turning over, etc., or whether there is a minute vibration associated with heartbeat or breathing, or the heart of the person who has landed The position of the human body is identified by detecting minute vibrations propagating through the bedding generated by the activity and breathing activity, and it is not easy to improve the sensitivity of the piezoelectric sensor unless a large one is used It is not easy to accurately detect a biological signal.

  Accordingly, an object of the present invention is to solve the above-described problems in the prior art and provide a biological signal detection apparatus capable of accurately detecting a biological signal with a simple configuration.

  In order to solve this problem, the present invention according to claim 1 is a biological signal detection device for detecting a biological signal of at least one of a user's heartbeat, body motion, and respiration, comprising a pair of electrodes, and A plate-like piezoelectric element having a piezoelectric body provided between the pair of electrodes, converting a force applied to the piezoelectric body into an electric charge to cause a voltage change in the pair of electrodes, and a surface direction of the piezoelectric element A voltage change between a pair of electrodes of the piezoelectric element and a rod-shaped pressure transmission means that protrudes along the line and has elasticity to amplify charges converted by the piezoelectric body, and based on this voltage change A biological signal detection apparatus comprising: a detection unit that detects the biological signal.

  According to a second aspect of the present invention, in the biological signal detection device according to the first aspect, the piezoelectric element is formed in a disk shape in which the piezoelectric body is polarized in the thickness direction, and electrodes are provided on both surfaces of the piezoelectric body. A plurality of pressure transmission means are attached so as to be spaced apart in the circumferential direction.

  According to a third aspect of the present invention, in the biological signal detection device according to the second aspect, the pressure transmitting means is attached to protrude in the radial direction of the piezoelectric body at positions spaced at equal intervals in the circumferential direction of the piezoelectric body. It is characterized by.

  According to a fourth aspect of the present invention, in the biological signal detection device according to any one of the first to third aspects, the piezoelectric device includes a plurality of piezoelectric elements, and one electrode of the plurality of piezoelectric elements is a linear conductive wire that is a pressure transmission means. It is electrically connected in series.

  According to a fifth aspect of the present invention, in the biological signal detection device according to any one of the first to fourth aspects, the piezoelectric element has one electrode formed in a flat plate shape, and a piezoelectric body is provided on both surfaces of the one electrode. The other electrode is provided on the surface of the body, respectively.

  According to a sixth aspect of the present invention, in the biological signal detection device according to any one of the first to fourth aspects, the pair of piezoelectric elements includes a pair of piezoelectric elements, and one electrode is formed in a flat plate shape. The other electrode is provided on the surface of the piezoelectric body, and the piezoelectric elements of the pair of piezoelectric elements are disposed so as to be opposed to each other. To do.

  According to a seventh aspect of the present invention, in the biological signal detection device according to any one of the first to sixth aspects, a force applied to the piezoelectric body via the pressure transmission means is applied to the charge in a state where at least the tip of the pressure transmission means protrudes to the outside. A cover member for covering and protecting the piezoelectric element so as to be convertible is provided.

  According to the present invention, the force applied to the pressure transmitting means is transmitted to the piezoelectric element by the rod-shaped pressure transmitting means provided so as to protrude along the surface direction of the piezoelectric element. The applied force can be amplified and the electric charge converted by this piezoelectric body can be increased. Therefore, by detecting the voltage change between the pair of electrodes of this piezoelectric element, the detection of the biological signal based on this voltage change can be performed more accurately. it can. In particular, since the rod-shaped pressure transmission means is attached to the piezoelectric element, the biological signal can be detected more accurately with a simple configuration than when, for example, a biological signal is detected by sensing a change in air pressure.

  In addition, since a plurality of pressure transmission means are attached to be separated from each other in the circumferential direction of the disk-shaped piezoelectric body, a voltage change due to the piezoelectric element can be amplified more efficiently and reliably by the plurality of pressure transmission means. It is possible to more accurately detect the user's biological signal based on the voltage change between the pair of electrodes of the element.

  In particular, by attaching the plurality of pressure transmission means at positions spaced apart at equal intervals in the circumferential direction of the piezoelectric body toward the radial direction of the piezoelectric body, a pair of piezoelectric elements via these pressure transmission means Since the voltage change between the electrodes can be amplified more evenly in the circumferential direction of the piezoelectric body, the detection of the user's biological signal based on the voltage change between the pair of electrodes of this piezoelectric element can be performed more accurately with a simple configuration. it can.

  Furthermore, by electrically connecting each of the electrodes of the plurality of piezoelectric elements in series with a linear conductive wire that is a pressure transmission means, the distance between the piezoelectric elements can be maintained with this conductive wire, Since this conductive line can be used as a ground line, and the force applied to the piezoelectric body by this conductive line can be amplified, the user's biological signal based on the voltage change between the pair of electrodes of the piezoelectric element can be amplified with a simple configuration. More accurate detection.

  Also, a piezoelectric element is provided with a piezoelectric body provided on both surfaces of one flat electrode, and the other electrode is provided on the surface of each piezoelectric body. One piezoelectric body and the other piezoelectric body of this piezoelectric element. And the voltage change generated in one of the piezoelectric bodies and the voltage change generated in the other piezoelectric body are reversed, and noise generated from these piezoelectric bodies can be canceled and reduced. It is possible to more accurately detect the user's biological signal based on the voltage change of the piezoelectric element.

  Similarly, a piezoelectric body is provided on one surface of a flat plate-like electrode, and the piezoelectric element side of a pair of piezoelectric elements in which the other electrode is provided on the surface of the piezoelectric body is opposed to each other. When the piezoelectric bodies of the pair of piezoelectric elements are AC connected, the voltage change generated in the piezoelectric body of one of the piezoelectric elements and the voltage change generated in the piezoelectric body of the other piezoelectric element are The noise of the voltage change that occurs in the reverse direction and that occurs in each piezoelectric body of these piezoelectric elements can be canceled and reduced, so that the detection of the user's biological signal based on the voltage change of these piezoelectric elements can be made more accurate.

  Further, in a state where at least the tip of the pressure transmission means of the piezoelectric element protrudes to the outside, the piezoelectric element is formed by the cover member so that the force applied to the piezoelectric body through the pressure transmission means can be converted into electric charges. By covering and protecting the piezoelectric element, it is possible to protect the piezoelectric element without suppressing the transmission of force to the piezoelectric body via these pressure transmission means. The durability of the element can be improved.

It is the schematic which shows the biosignal detection apparatus by the 1st Embodiment of this invention. It is sectional drawing which shows a part of said biological signal detection apparatus. It is a bottom view which shows the piezoelectric element of the said biosignal detection apparatus. It is a perspective view which shows the installation state of the said biosignal detection apparatus. It is the schematic which shows the biosignal detection apparatus by the 2nd Embodiment of this invention. It is the schematic which shows a part of biological signal detection apparatus by the 3rd Embodiment of this invention. It is the schematic which shows a part of biological signal detection apparatus by the 4th Embodiment of this invention. It is a front view which shows the outline | summary of the piezoelectric element of the biosignal detection apparatus by the 5th Embodiment of this invention. It is a perspective view which shows the outline | summary of the said piezoelectric element. It is the schematic of the biological signal detection apparatus by the 6th Embodiment of this invention, (a) is a top view, (b) It is a front view.

  A biological signal detection apparatus according to a first embodiment of the present invention will be described with reference to FIGS.

  The biological signal detection apparatus 1 is configured so that, for example, the presence / absence of a user is not attached to the user and is not restrained in addition to biological signals such as heartbeat, pulse, respiration, body movement, and fluctuation of the user (specimen). It is a bed sensor for detection. Specifically, the biological signal detection apparatus 1 is installed between, for example, a bed mat b and a sheet c of a user's bed a, and detects a biological signal of the user who uses the bed a. . In addition to the general adult bed a shown in FIG. 4, the biological signal detection apparatus 1 is attached to a baby bed, a futon, a blanket, a mattress, a chair, a toilet seat, a carpet, a bathtub, an automobile seat, and the like. It can also be used.

  As shown in FIG. 1, the biological signal detection device 1 includes a plurality of, for example, three substantially disk-shaped flexible piezoelectric elements (piezo elements) 2. These piezoelectric elements 2 are deformed by vibration and generate electric charges due to the piezoelectric effect to cause a voltage change between the electrodes. The piezoelectric elements 2 are electrically connected in series on the elastic sheet 3 having an elongated rectangular flat plate shape. Installed and protected. As shown in FIG. 2, the elastic sheet 3 is accommodated in a hollow sponge-like mat 4 as a sensor accommodating case having a long and narrow rectangular shape in plan view that can accommodate the elastic sheet 3, for example, a mattress or a bed. The sensor mat 5 has a length that is slightly smaller than the width of the mat or the like.

  Specifically, the piezoelectric element 2 is a piezoelectric sensor as a piezoelectric element that generates, for example, a unimorph type piezoelectric element, and is formed in a thin disk shape made of metal having conductivity and flexibility. Further, a thin metal plate 11 that is an elastic plate as one electrode is provided. The metal thin plate 11 has a diameter of, for example, about 3 cm to 5 cm, and a disk-shaped piezoelectric body 12 polarized in the thickness direction is concentrically formed on the surface which is one surface of the metal thin plate 11. Is provided. The piezoelectric body 12 is formed to have a diameter smaller than the diameter of the metal thin plate 11, for example, about one half. The piezoelectric body 12 is formed by using a thin film of a polymer voltage material such as polyvinylidene fluoride (PVDF), and the piezoelectric body 12 has at least a vertical component. When a force is applied, a charge proportional to the force is generated based on the fact that the relative position of ions changes due to the strain of the material constituting the piezoelectric body 22. Further, a conductive metal thin film 13 serving as the other electrode is laminated on the surface of the piezoelectric body 12, and electric charges generated in the piezoelectric body 12 are transferred to the metal thin plate 11, the metal thin film 13, and the like. To cause a voltage change. Here, the metal thin film 13 is formed by, for example, applying a silver paste or the like to the surface of the piezoelectric body 12.

  And the elastic sheet 3 in which these piezoelectric elements 2 are installed is formed of a sheet body having an elongated rectangular shape in plan view having elasticity such as synthetic resin or rubber, and on the surface of the elastic sheet 3, For example, three piezoelectric elements 2a, 2b, 2c are arranged in a straight line. These piezoelectric elements 2a, 2b, 2c are arranged along the longitudinal direction of the elastic sheet 3, as shown in FIG. 1, and each of these piezoelectric elements is positioned at the center in the width direction of the elastic sheet 3. 2a, 2b, 2c are installed in a state where the side on which the piezoelectric body 12 is provided faces the surface side of the elastic sheet 3.

  Specifically, the piezoelectric element 2a located near one end in the longitudinal direction of the elastic sheet 3 is installed at a position separated from the one end edge in the longitudinal direction of the elastic sheet 3 to the other end side by a predetermined distance. A positioning hook 14 as a holding means for holding the mounting position of the piezoelectric element 2a is attached to the metal thin plate 11 of the piezoelectric element 2a. The positioning hook 14 is formed of a conductive metal thin plate, and is connected to the edge of the back surface of the metal thin plate 11 of the piezoelectric element 2a by welding or the like. A portion 15 is provided. The positioning hook 14 is attached in a state of being positioned by hooking the hook portion 15 of the positioning hook 14 to one end edge in the longitudinal direction of the elastic sheet 3.

  Further, each of the piezoelectric elements 2 a, 2 b, 2 c is connected in series with a ground line 16 as a conductive line having conductivity wired along the longitudinal direction of the elastic sheet 3. The ground line 16 is wired so as to pass through the center position of the back surface of the thin metal plate 11 of each piezoelectric element 2a, 2b, 2c. In the piezoelectric element 2a, the back surface of the thin metal plate 11 of the piezoelectric element 2a is provided. The tip of the ground wire 16 is attached by soldering or the like to the edge opposite to the position where the positioning hook 14 is attached, and is electrically connected. Further, the piezoelectric element 2b positioned substantially in the middle of the elastic sheet 3 in the longitudinal direction and the piezoelectric element 2c positioned near the other end in the longitudinal direction of the elastic sheet 3 excluding the piezoelectric element 2a , 2c, the ground wire 16 is attached by soldering or the like at the center position of the back surface of each thin metal plate 11 and is electrically connected.

  The other end of the ground line 16 is electrically connected to a signal processing circuit 17 serving as a detection unit. The signal processing circuit 17 includes an amplifier (not shown), detects a voltage change between the metal thin plate 11 and the metal thin film 13 of each piezoelectric element 2a, 2b, 2c, and based on this voltage change. Thus, a biosignal such as a user's heartbeat, pulse, body motion, respiration, body motion, fluctuation, etc., the presence / absence of the user, etc. are detected, for example, a notification device or a safety confirmation notification device connected to this signal processing circuit 17 Information related to the user's biological signal, for example, safety information transmitted when the user's biological signal cannot be sensed for a predetermined time, for example, 30 minutes, via an emergency management device (not shown) such as The information is configured to be transmitted to a pre-registered partner via a communication means such as a telephone or electronic mail.

  In addition, an AC adapter (not shown) is connected to the signal processing circuit 17, and power is supplied to the signal processing circuit 17 through the AC adapter. Here, a battery or the like can be built in the signal processing device 17 to eliminate the need for an AC adapter. In addition, the signal processing device 17 may be configured to be wireless, and the signal processing device 17 and the emergency management device may be wirelessly connected.

  Furthermore, as shown in FIGS. 1 and 3, one end of a lead wire 18 as a separate detection wiring is attached to the metal thin plate 11 of each piezoelectric element 2a, 2b, 2c by soldering or the like. It is connected to the. That is, the piezoelectric elements 2a, 2b, and 2c are connected to one end portions of the corresponding lead wires 18a, 18b, and 18c on the outer peripheral edges of the back surfaces of the thin metal plates 11 of the piezoelectric elements 2a, 2b, and 2c, respectively. Further, the other end of each of the lead wires 18a, 18b, 18c is electrically connected to and attached to the signal processing circuit 17. The signal processing circuit 17 is installed at the other end in the longitudinal direction of the elastic sheet 3, and is housed and attached in the sponge mat 4 together with the elastic sheet 3 and the piezoelectric elements 2a, 2b, 2c. ing.

  On the other hand, on the edge of the back surface of the thin metal plate 11 of each of the piezoelectric elements 2a, 2b, 2c, a vibration transmission pin 19 having a long and thin bar shape as a pressure transmission means for picking up and transmitting vibration is provided. Each is attached in plural, for example two. These vibration transmission pins 19 are formed of a material having flexibility and restoring force, such as a guitar wire or a piano wire, and amplifies a biological signal of the user's human body placed on the biological signal detection device 1. It is attached to enable detection with high accuracy. These vibration transmission pins 19 have a length dimension substantially equal to the diameter dimension of the thin metal plate 11 of each piezoelectric element 2a, 2b, 2c, and the thin metal plate 11 of each piezoelectric element 2a, 2b, 2c. It is attached to face along the radial direction passing through the center. That is, these vibration transmission pins 19 are attached in the radial direction orthogonal to the longitudinal direction of the ground wire 16 and are attached by projecting along the surface direction of the metal thin plate 11 of each piezoelectric element 2a, 2b, 2c. It has been. In other words, the vibration transmission pins 19 protrude along the width direction of the elastic sheet 3, and the length of the vibration transmission pins 19 is such that the front ends of the vibration transmission pins 19 are located near both side edges in the width direction of the elastic sheet 3. Dimension is formed. Further, these vibration transmission pins 19 are attached at positions spaced at equal intervals in the circumferential direction of the piezoelectric elements 2a, 2b, 2c toward the radial direction of the piezoelectric elements 2a, 2b, 2c.

  Each of these vibration transmission pins 19 transmits vibration sensed by the vibration transmission pins 19 themselves to the metal thin plate 11 of the piezoelectric element 2. Specifically, these vibration transmission pins 19 are provided with the vibration transmission pins 19 so that the force applied to the vibration transmission pins is applied to the thin metal plate 11 as compared with the case where the vibration transmission pins 19 are not provided. The metal thin plate 11 is vibrated and deformed more greatly, and a large force is applied to the piezoelectric body 12 of the piezoelectric element to which the vibration transmitting pins 19 are attached, and the electric charge converted by the piezoelectric body 12 is increased. For example, it is made of an elastic material such as a metal wire. Here, the ground wire 16 connected to each piezoelectric element 2 is also configured to function as a pressure transmission means, similarly to the vibration transmission pin 19. That is, the ground wire 16 also transmits vibration sensed by the ground wire 16 itself to the metal thin plate 11 of the piezoelectric element 2, and the metal thin plate 11 is made larger than when the ground wire 16 is not provided. The electric charge converted by the piezoelectric body 12 of the piezoelectric element 2 to which the ground line 16 is connected is increased and the voltage change between the metal thin plate 11 and the metal thin film 13 is amplified.

  Next, the operation of the biological signal detection device 1 will be described.

<Installation>
For example, the longitudinal direction of the sensor mat 5 of the biological signal detection device 1 is aligned with the width direction of the user's bed a, and in this state, the biological signal is placed between the bed mat b and the sheet c of the user's bed a. The processing apparatus 1 is installed and set.

  Next, if necessary, an emergency management device is connected to the signal processing circuit 17 of the biological signal detection device 1, and the emergency management device is connected to a telephone line or an Internet line, and various kinds of information transmitted from the emergency management device are transmitted. Information, a destination such as a telephone number or an e-mail address, etc. are appropriately set.

  Further, an AC adapter is connected to the signal processing circuit 17 of the biological signal detection apparatus 1, and power is supplied to the signal processing circuit 17 through the AC adapter.

<Operation>
In this state, when the user is placed on the bed a where the biological signal detection device 1 is installed, the metal thin plate 11, the vibration transmission pin 19, or the ground of at least one piezoelectric element 2 of the biological signal detection device 1. When a pressure having a force component at least in the vertical direction is applied to any of the lines 16, the force applied to the metal thin plate 11, the vibration transmission pin 19, or the ground line 16 is transmitted to the piezoelectric body 12 of the piezoelectric element 2. A force is applied to the piezoelectric body 12 to deform it.

  At this time, when a force is directly applied to the metal thin plate 11 of the piezoelectric element 2, the piezoelectric body 12 is deformed in the thickness direction by deformation of the metal thin plate 11 in the thickness direction. Further, when a force is applied to any vibration transmission pin 19 attached to the piezoelectric element 2, the vibration transmission pin 19 is deformed, and the deformation of the vibration transmission pin 19 is vibrated to the thin metal plate 11. The thin metal plate 11 is deformed in the thickness direction, and the piezoelectric body 12 is deformed in the thickness direction via the thin metal plate 11. Further, when a force is applied to the ground line 16, the ground line 16 is deformed, and the deformation of the ground line 16 is caused by the deformation of the piezoelectric element 2 positioned close to the position where the force is applied to the ground line 16. The vibration is transmitted to the metal thin plate 11, the metal thin plate 11 is deformed in the thickness direction, and the piezoelectric body 12 is deformed in the thickness direction via the metal thin plate 11.

  That is, since the vibration transmission pin 19 and the ground wire 16 protrude in the radial direction of the piezoelectric element 2, the piezoelectric element is caused by the flexibility of the vibration transmission pin 19 and the ground wire 16, that is, elastic deformation. Even if the force applied to 2 itself is small to some extent, the force applied to the vibration transmission pin 19 and the ground wire 17 is transmitted to the metal thin plate 11 as vibration and amplified, and the vibration transmission pin 19 and the ground wire 16 are connected. The thin metal plate 11 of the piezoelectric element 2 is greatly elastically deformed, and a large force is applied to the piezoelectric body 12 via the elastic deformation of the thin metal plate 11 to deform it. Then, the relative position of the ions changes due to the strain of the material constituting the piezoelectric body 22, and an electric charge proportional to the force is generated, and between the metal thin plate 11 and the metal thin film 13 positioned with the piezoelectric body 12 interposed therebetween. A relatively large voltage change occurs.

  Then, the voltage change between the metal thin plate 11 and the metal thin film 13 is transmitted to the signal processing circuit 17 through the lead wire 18, and the heartbeat, pulse, respiration, A biological signal such as body movement and fluctuation, the presence or absence of a user, and the like are detected by signal processing in the signal processing circuit 17.

  Further, if necessary, it is transmitted via the emergency management device connected to the signal processing circuit 17 when information on the user's biological signal, for example, the user's biological signal cannot be sensed for a predetermined time, for example, 30 minutes. Safety information such as safety information is transmitted to a telephone number or an e-mail address registered in advance via a telephone line or an Internet line by telephone or e-mail.

  As described above, the rod-shaped vibration transmission pin 19 provided so as to protrude along the surface direction of one of the piezoelectric elements 2 of the biological signal detection device 1 when the user is placed on the biological signal detection device 1 or the like. In addition, when a force including at least a component in the vertical direction is applied, the deformation of the vibration transmission pin 19 is transmitted as vibration to the metal thin plate 11, and this vibration is transmitted from the metal thin plate 11 to the piezoelectric body 12.

  Therefore, since the vibration transmission pin 19 is provided so as to protrude in the radial direction of the piezoelectric element 2, more force is applied to the piezoelectric body 12 of the piezoelectric element 2 than when the vibration transmission pin 19 is not provided. The electric charge that can be greatly amplified and converted according to the force applied to the piezoelectric body 12 can be increased. Therefore, the voltage change generated between the metal thin plate 11 and the metal thin film 13 of these voltage elements 2 can be increased, and this voltage change is signal-processed by the signal processing circuit 17 to detect a biological signal based on this voltage change. Can be more accurate.

  For this reason, the biological signal detection device 1 is installed between the bed mat b and the sheet c, and the detection signal of the user is reduced, stray noise is increased, and malfunction may occur. However, since the user's biological signal can be amplified and detected by the piezoelectric element 2 of the biological signal detection device 1, the user's biological signal can be detected accurately.

  That is, even when the small piezoelectric element 2 having a relatively small diameter is used, the small piezoelectric element 2 can be obtained by attaching the vibration transmission pin 19 to the metal thin plate 11 of the small piezoelectric element 2. The apparent radial size including the vibration transmission pin 19 can be increased, and the force applied to the vibration transmission pin 19 can be transmitted to the metal thin plate 11 to be amplified. As a result, the sensitivity of the piezoelectric element 2 can be increased. Can be improved. Therefore, since the sensitivity of the piezoelectric element 2 can be improved with a simple configuration in which these vibration transmission pins 19 are attached to the piezoelectric element 2, the sensitive biological signal detection device 1 can be manufactured at low cost, and productivity can be improved. .

  In particular, since the rod-shaped vibration transmission pin 19 is attached to the thin metal plate 11 of each piezoelectric element 2, it can be used more accurately with a simple configuration than when, for example, detecting a change in air pressure to detect a biological signal. A person's biological signal can be detected, and various symptoms obtained from the correlation between respiration and pulse can be predicted. That is, it becomes possible to predict apnea syndrome and deep sleep, and predict the onset of dementia.

  In addition, the plurality of vibration transmission pins 19 are attached at a distance from each other in the circumferential direction of the disk-shaped thin metal plate 11 of the piezoelectric element 2 so as to protrude in opposite directions. By simply applying a force to any one of them, the force applied to the vibration transmission pin 19 can be transmitted and amplified to the thin metal plate 11, and the amplified force can be transmitted from the thin metal plate 11 to the piezoelectric body 12. Therefore, since the electric charges generated in the piezoelectric body 12 can be amplified efficiently and reliably, the living body of the user by the signal processing circuit 17 based on the voltage change between the metal thin plate 11 and the metal thin film 13 of each piezoelectric element 2 is obtained. The signal can be detected more accurately.

  In particular, these vibration transmission pins 19 are attached by projecting in the radial direction of the thin metal plate 21 at positions spaced apart by 180 ° in the circumferential direction of the thin metal plate 11 of the piezoelectric element 2. By arranging the piezoelectric elements 2 on the elastic seed 3 in a state where the pins 19 are along the width direction of the elastic sheet 3, the elastic sheet 3 is provided by the vibration transmission pins 19 of the piezoelectric elements 2. The force applied to both sides of the piezoelectric element 2 can be detected, and the transmission of the force to the piezoelectric body 12 of the piezoelectric element 2 via these vibration transmission pins 19 and the voltage change between the thin metal plate 11 and the thin metal film 13 are detected by this piezoelectric element. Since the amplification can be performed more evenly in the circumferential direction of the element 2, the detection of the user's biological signal based on the voltage change between the metal thin plate 11 and the metal thin film 13 of the piezoelectric element 2 can be more accurately performed with a simple configuration. And it can be securely.

  Further, since the metal thin film 11 of each of the plurality of piezoelectric elements 2a, 2b, and 2c is electrically connected in series linearly with a ground line 16 having a vibration transmission function similar to that of the vibration transmission pin 19, each of these piezoelectric elements The distance between 2a, 2b, and 2c is reliably held by the ground line 16, and the displacement of each of the piezoelectric elements 2a, 2b, and 2c can be surely prevented. Since the force applied to the ground wire 19 can be transmitted to the metal thin plate 11 as a vibration and amplified similarly to the vibration transmission pin 19, the piezoelectric element 2 can be grounded with a simple configuration. More accurately and reliably detecting a user's biological signal based on a voltage change between the thin metal plate 11 and the thin metal film 13 positioned with the piezoelectric body 12 interposed therebetween. Kill.

  As described above, since the biological signal of the user who lies on the bed a can be accurately and reliably detected, the sleeping state of an elderly person living alone or a non-caregiver at home, etc., can be checked to accurately land and leave the bed a. It becomes possible to grasp. For this reason, by installing the biological signal detection device 1 in each room of an apartment or a condominium and managing it centrally, etc., it is possible to promote the residence of elderly people who are living alone or non-caregivers, and it is possible to prevent lonely death and unrelated death. In addition, since the signal processing circuit 17 of the biological signal detection apparatus 1 may be connected to a medical institution or a care station for remote monitoring or connected to a social welfare network, it is particularly effective for social welfare. .

  In the first embodiment, as shown in FIG. 1, the vibration transmission pin 19 of each piezoelectric element 2 is configured to protrude in the opposite direction along the width direction of the elastic sheet 3. 5, for example, four vibration transmission pins 19 are attached to the thin metal plate 11 of each piezoelectric element 2, and these four vibration transmission pins 19 are attached to the thin metal plate, as in the second embodiment of the present invention shown in FIG. It can also be set as the structure attached to the surface of 11 at equal intervals of 90 degrees toward the circumferential direction.

  Specifically, each of these piezoelectric elements 2 is arranged with a total of four piezoelectric elements 2a, 2b, 2c, 2d arranged at equal intervals along the longitudinal direction of the elastic sheet 3, and these piezoelectric elements 2a, Each of the thin metal plates 11 of 2b, 2c, and 2d is electrically connected to the ground line 16 and connected in series. Furthermore, lead wires 18a, 18b, 18c, and 18d are connected to the metal thin films 11 of the piezoelectric elements 2a, 2b, 2c, and 2d, and each of the lead wires 18a, 18b, 18c, and 18d is a signal. It is electrically connected to the processing circuit 17.

  The vibration transmission pins 19 of the piezoelectric elements 2a, 2b, 2c, and 2d are installed at an angle of 45 ° with respect to the three longitudinal directions of the elastic sheet, and the piezoelectric elements 2a, 2b, A ground line 16 is wired so as to pass over the center of the back surface of the thin metal plate 11 of 2c, 2d, and the center position of the back surface of the thin metal plate 11 of each of the piezoelectric elements 2a, 2b, 2c, 2d and the ground line 16 are arranged. They are connected by soldering or the like and electrically connected in series.

  Therefore, as described above, the number of vibration transmission pins 19 attached to each piezoelectric element 2 is increased from two to four, and these four vibration transmission pins 19 are equally spaced with a good balance toward the circumferential direction of the thin metal plate 11. Even if the force is applied to any one of these four vibration transmission pins 19, the vibration is transmitted from any one of these vibration transmission pins 19 to the metal thin plate 11 of the piezoelectric element 2. By amplifying, the piezoelectric body 12 can be deformed, and a voltage change can be surely generated between the metal thin plate 11 and the metal thin film 13 positioned with the piezoelectric body 12 interposed therebetween. That is, since a force over a wider range on the sensor mat 5 can be sensed by the piezoelectric element 2 via the vibration transmission pin 19, detection of a user's biological signal by the piezoelectric element 2 can be performed with a simple configuration. Sensitive and accurate.

  Further, as in the third embodiment of the present invention shown in FIG. 6, the piezoelectric members 12a and 12b are provided on both surfaces of the thin metal plate 11, respectively, and the metal thin films 13a and 13b are provided on the surfaces of the piezoelectric members 12a and 12b, respectively. A laminated bimorph type piezoelectric element 2A can also be used. The piezoelectric element 2A is a balanced piazzo electric element having excellent noise resistance, and the piezoelectric bodies 12a and 12b are made of the same material and the same material and have the same characteristics. It is configured. That is, the piezoelectric element 2A is configured such that the displacement of charges generated in the piezoelectric bodies 12a and 12b provided on both surfaces of the thin metal plate 11 is symmetric.

  In the piezoelectric element 2A, one end portions of lead wires 18d and 18e are electrically connected to the metal thin films 13a and 13b by soldering or the like. The ground wire is connected to the metal thin plate 11 of the piezoelectric element 2A. One end of 16 is electrically connected by soldering or the like. The other ends of the lead wires 18d and 18e and the ground wire 16 are electrically connected to the signal processing circuit 17, and the voltage change between the lead wire 18d and the ground wire 16, the lead wire 18e and the ground wire 16 are grounded. Each of the voltage changes between the lines 16 is signal-processed by the signal processing circuit 17, and a biological signal of the user is detected. At this time, as the lead wires 18d and 18e and the ground wire 16, a three-core shielded wire or the like can be used.

  At this time, in the piezoelectric element 2A, for example, in the state A in which the metal thin plate 11 is curved in a concave arc shape shown in FIG. 6, the metal thin film 13a on the piezoelectric body 12a side of the piezoelectric element 2A is charged positively (+). At the same time as the metal thin plate 11 is negatively charged (−), the metal thin film 13b on the piezoelectric body 12b side of the piezoelectric element 2A is negatively charged (−), and the metal thin plate 11 is charged positively (+). An inverted electric field, that is, a voltage change is generated between the metal thin films 13a and 13b and the metal thin plate 11. On the contrary, for example, in the state B in which the metal thin plate 11 is curved in a convex arc shape shown in FIG. 6, the metal thin film on the piezoelectric body 12a side of the piezoelectric element 2A is negatively charged (−), and the metal thin plate 11 is positive. At the same time as charging to (+), the metal thin film 13b on the piezoelectric body 12b side of the piezoelectric element 2A is charged to plus (+), the metal thin plate 11 is charged to minus (-), and these metal thin films 13a and 13b An inverted electric field, that is, a voltage change is generated between the thin metal plate 11.

  Therefore, the voltage change between the metal thin film 13a and the metal thin plate 11 located between the one piezoelectric body 12a of the piezoelectric element 2A, the metal thin film 13b located between the other piezoelectric body 12b of the piezoelectric element 2 and The voltage change between the thin metal plates 11 occurs in an inverted and balanced state. Therefore, when one piezoelectric body 12a and the other piezoelectric body 12b of the piezoelectric element 2A are AC-connected, a voltage change generated in the one piezoelectric body 12a and a voltage change generated in the other piezoelectric body 12b Are reversed and appear as opposite phases, and noise (floating noise) generated when charges are generated in each of the piezoelectric bodies 12a and 12b appear as in-phase, cancel each other, can be reduced, and noise can be reduced. For this reason, since the SN ratio of the piezoelectric element 2A can be increased and the noise characteristics of the piezoelectric element 2A can be improved, the detection of the user's biological signal based on the voltage change of the piezoelectric element 2A can be performed more accurately and accurately.

  Further, as in the fourth embodiment of the present invention shown in FIG. 7, the unimorph piezoelectric elements 2a and 2b of the first embodiment are used instead of the piezoelectric element 2A of the third embodiment. It is also possible to use the piezoelectric device 21 as a piezoelectric element in which the metal thin plates 11a and 11b are overlapped and the piezoelectric bodies 12a and 12b are provided on both surfaces. The piezoelectric device 21 is configured such that the piezoelectric bodies 12a and 12b of the piezoelectric elements 2a and 2b are made of the same material and the same material and have the same characteristics. In addition, the thin metal plates 11a and 11b of the piezoelectric elements 2a and 2b are disposed in a state where the back surfaces on the side where the piezoelectric bodies 12a and 12b are not provided are opposed to each other, that is, the piezoelectric bodies 12a and 12b are provided. In this state, the change in the electric charges generated in the piezoelectric bodies 12a and 12b is symmetrical. In this case as well, as in the third embodiment, lead wires 18d and 18e are connected to the metal thin films 13a and 13b covering the piezoelectric bodies 12a and 12b of the piezoelectric elements 2a and 2b, respectively. By connecting a ground wire 16 to each of the thin metal plates 11a and 11b of 2b, a voltage change between the thin metal plate 13a and the thin metal plate 11a located across the piezoelectric body 12a of the one piezoelectric element 2a, and the other piezoelectric element The voltage change between the metal thin film 13b and the metal thin plate 11b positioned with the 2b piezoelectric body 12b interposed therebetween occurs in an inverted and balanced state.

  Accordingly, by connecting the thin metal films 13a and 13b of the piezoelectric elements 2a and 2b of the piezoelectric device 21 with an alternating current, a voltage change generated in the piezoelectric body 12a of the one piezoelectric element 2a and a piezoelectricity of the other piezoelectric element 2b. Since the voltage change generated in the body 12b appears to be reversed and noise generated when charges are generated in the piezoelectric bodies 12a and 12b of the piezoelectric elements 2a and 2b can be canceled and reduced, the third embodiment described above. In addition to having the same operational effects as those of the above-described embodiment, the general unimorph type piezoelectric elements 2a and 2b are simply installed in an overlapping manner. Detection can be performed with higher accuracy and accuracy with a simple configuration.

  Furthermore, as the lead wires 18d and 18e connected to the metal thin films 13a and 13b of the piezoelectric elements 2a and 2b of the piezoelectric device 21, a two-core shielded wire can be used, and these lead wires 18d and 18e and signal processing are used. A balance amplifier 22 as a noise blocking means for blocking noise generated between the lead wires 18d and 18e can be electrically attached between the circuit 17 and the circuit 17. The balance amplifier 22 includes an operational amplifier 23 that is an operational amplifier. A non-inverting input terminal 24 that is a plus (+) terminal of the operational amplifier 23 is electrically connected to the metal thin film 13b of one piezoelectric element 2b. A resistor R1 is electrically connected in series between the metal thin film 13b and the non-inverting input terminal 24. Further, the inverting input terminal 25 which is a minus (−) terminal of the operational amplifier 23 is electrically connected to the metal thin film 13 a of the other piezoelectric element 2 a, and between the metal thin film 13 a and the inverting input terminal 25. A resistor R2 is electrically connected in series. Further, a resistor R3 is electrically connected in parallel between the resistor R2 and the inverting input terminal 25 and between the output terminal 26 of the operational amplifier 23.

  Therefore, by connecting the balance amplifier 22 between the metal thin films 13a and 13b of the piezoelectric elements 2a and 2b of the piezoelectric device 21, between the metal thin plates 11a and 11b of the piezoelectric elements 2a and 2b and the metal thin films 13a and 13b. Therefore, the detection of the user's biological signal using the piezoelectric device 21 based on the voltage change of the piezoelectric elements 2a and 2b can be performed more accurately and accurately.

  Further, as in the fifth embodiment of the present invention shown in FIGS. 8 and 9, each of the piezoelectric elements 2 of the biological signal detecting device 1 is protected as a cover member that prevents the piezoelectric elements 2 from being damaged. It can also be installed on the elastic sheet 3 while being covered and accommodated by 31. The protective case 31 is made of, for example, a metal such as aluminum, and includes a pair of a lower case 32 and an upper case 33 that are square plates in plan view. The lower case 32 and the upper case 33 are formed in a rectangular flat plate shape having the same size, and are larger than the width dimension of the thin metal plate 11 of the piezoelectric element 2 and transmit vibrations projecting in a direction opposite to the piezoelectric element 2. The pin 19 is formed in a size smaller than the length between the tips.

  Specifically, the upper case and the lower surface of the lower case 32 are flat surfaces, and screw insertion holes 34 penetrating in the thickness direction are provided at the respective corners of the lower case 32. On the lower surface side of the position where the screw insertion hole 34 of the lower case 32 is provided, a screw 42 screwed to the head portion 42 of the screw 41 inserted into the screw insertion hole 34 or the shaft portion 43 of the screw. A fitting recess 35 into which a nut 44 as a stop member is fitted is provided.

  Next, the upper case 33 has a flat surface, and the upper case 33 has a circular shape in a plan view and a concave shape in a side view in which the piezoelectric element 2 is fitted and positioned and held at the center of the lower surface. A recess 36 is provided. The housing recess 36 has an inner diameter larger than the outer diameter of the metal thin plate 11 of the piezoelectric element 2, and the piezoelectric body 12 and the metal thin film 13 are laminated on the thickest metal thin plate 11 of the piezoelectric element 2. The depth is larger than the thickness of the center position. That is, the accommodation recess 36 is in an undeformed state in which none of the metal thin plate 11, the piezoelectric body 12, and the metal thin film 13 of the piezoelectric element 2 installed on the lower case 32 is in contact, that is, the piezoelectric body 12 is charged. The piezoelectric element 11 can be accommodated in the accommodating recess 36 in a state where it does not occur.

  Further, at each corner of the upper case 33, screw insertion holes 37 communicating with the screw insertion holes 34 of the lower case 32 are penetrated in the thickness direction in a state where the upper case 33 is overlapped with the lower case 32. Is provided. A fitting recess into which the head portion 42 or the nut 44 of the screw 41 inserted into the screw insertion hole 37 is also fitted on the upper surface side of the position where the screw insertion hole 37 of the upper case 33 is provided. 38 are provided.

  In the upper case 33 and the lower case 32, the piezoelectric element 2 is accommodated in the accommodating recess 36 of the upper case 32, and the vibration transmission pins 19 attached to the piezoelectric element 2 are connected to the upper case 33 and the lower case 32. The piezoelectric element 2 is installed and attached so as to project outward from the edges of the upper case 33 and the lower case 32 through the space between the cases 32. Further, screws 41 are respectively inserted between the screw insertion holes 34 and 37 communicating with the upper case 33 and the lower case 32, and are respectively screwed with nuts 44. Are accommodated in the fitting recesses 34, 37 of either the upper case 33 or the lower case 32, and are attached so as not to protrude from the upper surface of the upper case 33 or the lower surface of the lower case 32.

  At this time, the screw 41 and the nut 44 allow the vibration transmitting pin 19 that passes between the lower surface of the upper case 33 and the upper surface of the lower case 32 to protrude to the outside from the housing recess 36 of the upper case 33. In order not to apply any force, the distance between the lower surface of the upper case 33 and the upper surface of the lower case 32 is positioned so as to be larger than the thickness dimension of these vibration transmission pins 19, that is, the outer diameter dimension. Is retained. Further, these vibration transmission pins 19 project vertically from an intermediate position of one side of the upper case 33 and the lower case 32 in a state where the longitudinal direction is along one of the upper case 33 and the lower case 32. Is attached.

  As described above, the metal of the piezoelectric element 2 is protruded outside while projecting the tip of the vibration transmitting pin 19 of each piezoelectric element 2 installed on the elastic sheet 3 of the biological signal detecting device 1 and accommodated in the sponge mat 4. The sensor mat of the biological signal detection device 1 in a state where the piezoelectric element 2 is accommodated in the accommodation recess 36 of the upper case 33 so that the pressure is not directly applied to each of the thin plate 11, the piezoelectric body 12 and the metal thin film 13. 5 is applied from the metal thin plate 11 to the piezoelectric body 12 via the vibration transmission pin 19, and this force is converted into electric charge by the piezoelectric body 12, and the metal thin plate 11 and the metal thin film Each of the piezoelectric elements 2 is accommodated in a protective case 31 to be protected so that a voltage change occurs between them.

  As a result, the sandwich structure of the upper case 33 and the lower case 32 of the protective case 31 protects the piezoelectric element 2 in a free state in which it does not receive external force directly. Without suppressing the transmission of force to the piezoelectric body 12 via the transmission pin 19, it is possible to prevent the application of force to the metal thin plate 11, the piezoelectric body 12 and the metal thin film 13 itself of the piezoelectric element 2 with the protective case 31. Since it is possible to prevent excessive pressurization and elastic deformation of the metal thin plate 11, the piezoelectric body 12 and the metal thin film 13, that is, addition of mechanical stress, the metal thin plate 11, the piezoelectric body 12 and the metal thin film 13 can be securely attached. Can protect. Therefore, by accommodating the piezoelectric element 2 in the protective case 31 and protecting it, the noise balance to the piezoelectric element 2 can be improved, and the detection accuracy of the user's biological signal by the piezoelectric element 2 can be maintained, while this Since the durability of the piezoelectric element 2 can be improved, the durability of the biological signal detection device 1 can be improved, and the user-friendliness can be improved.

  Furthermore, as in the sixth embodiment of the present invention shown in FIGS. 10A and 10B, only one piezoelectric element 2 of the biological signal detection device 1 is provided, and the biological signal detection device 1 The signal processing circuit 17 can be wireless. The signal processing circuit 17 is provided with a weak current transmitter 51 as radio wave transmitting means, and a transmission antenna 52 is attached to the weak current transmitter 51. Further, a battery 53 serving as a power source for driving the signal processing circuit 17 is attached to the signal processing circuit 17, and each of the signal processing circuit 17, the weak current transmitter 51, and the battery 52 is a case body. Is housed in a main body case 54. The main body case 54 is made of, for example, a synthetic resin such as plastic, and is attached by raising the upper surface side of the sponge mat 4.

  Further, one piezoelectric element 2 is accommodated in the sponge-like mat 4, and this piezoelectric element 2 is configured as a balanced sensor. The piezoelectric element 2 is connected to the signal processing circuit 17 via a signal line 55 that is a lead wire, and is installed at the center position in the longitudinal direction and the width direction of the sponge mat 4. Each vibration transmission pin 19 of the piezoelectric element 2 is provided so as to protrude toward each corner of the sponge mat 4.

  As a result, by attaching the weak current transmitter 51 and the transmission antenna 52 to the biological signal detection device 1 and the battery 53, the biological signal detection device 1 can be used as an emergency management device such as a notification device or a safety confirmation notification device. Since the wireless connection is possible and it is not necessary to connect to a commercial power source or the like, the usability of the biological signal detection device 1 itself can be improved as compared with the case where the biological signal detection device 1 is connected by wire.

  In each of the above embodiments, two or four vibration transmission pins 19 are attached to the piezoelectric element 2. However, as many vibration transmission pins 19 are attached to the piezoelectric element 2 as necessary. Also good. Moreover, although the ground wire 16 that acts in the same manner as the vibration transmission pin 19 is used, the ground wire 16 is simply used for ground using an electric wire or the like that does not have elasticity and flexibility, and is similar to the vibration transmission pin 19. It can also be set as the structure which does not produce an effect | action.

  In addition, the piezoelectric body 12 of the piezoelectric element 2 can be configured by using various crystals such as quartz, Rochelle salt, barium titanate, lithium niobate, and piezoelectric ceramics, and piezoelectrics polarized in the thickness direction. In addition to the body 12, a material polarized in the radial direction can also be used. In addition to the above-described unimorph type and bimorph type, the piezoelectric element 2 includes any type of piezo such as a single plate type, a laminated type, a Mooni type, a cymbal type, a monomorph type, a multimorph type, and the like. Even an electric element can be used correspondingly.

  Further, in the sixth embodiment, the signal processing circuit of the biological signal detection apparatus 1 is wirelessly connected. However, a terminal circuit that can be connected to the outside with a telephone line or a terminal circuit that can be connected to a LAN is connected to the signal processing circuit. It can also be an integrated structure.

DESCRIPTION OF SYMBOLS 1 Biosignal detection apparatus 2, 2a, 2b, 2c, 2d, 2A Piezoelectric element 3 Elastic sheet 4 Sponge-like mat 5 Sensor mat 11 Metal thin plate (electrode)
12, 12a, 12b Piezoelectric bodies 13, 13a, 13b Metal thin films (electrodes)
14 Positioning hook 15 Hook part 16 Ground line 17 Signal processing circuit (detection part)
18, 18a, 18b, 18c, 18d, 18e Lead wire 19 Vibration transmission pin (pressure transmission means)
21 Piezoelectric devices (piezoelectric elements)
22 Balance amplifier 23 Operational amplifier 24 Non-inverting input terminal 25 Inverting input terminal 26 Output terminal 31 Protective case (cover member)
32 Lower case 33 Upper case 34 Screw insertion hole 35 Fitting recess 36 Housing recess 37 Screw insertion hole 38 Fitting recess 41 Screw 42 Head 43 Shaft 44 Nut 51 Weak current transmitter 52 Transmitting antenna 53 Battery 54 Main body case 55 Signal Line a Bed b Bed mat c Sheet A Curved in a concave arc B Curved in a convex arc R1, R2, R3 Resistance

Claims (7)

A biological signal detection device for detecting a biological signal of at least one of a user's heartbeat, body movement and respiration,
A plate-like piezoelectric element having a pair of electrodes and a piezoelectric body provided between the pair of electrodes, and converting a force applied to the piezoelectric body into an electric charge to cause a voltage change in the pair of electrodes;
A rod-shaped pressure transmission means that has elasticity to amplify the electric charge that is provided along the surface direction of the piezoelectric element and is converted by the piezoelectric body;
Detecting a voltage change between a pair of electrodes of the piezoelectric element, and detecting the biological signal based on the voltage change;
A biological signal detection device comprising: The piezoelectric element is formed in a disk shape in which a piezoelectric body is polarized in the thickness direction, electrodes are provided on both surfaces of the piezoelectric body, and a plurality of pressure transmission means are attached in a circumferential direction of the piezoelectric body. The biological signal detection device according to claim 1, wherein The biological signal detection device according to claim 2, wherein the pressure transmission means is attached so as to protrude in the radial direction of the piezoelectric body at positions spaced apart at equal intervals in the circumferential direction of the piezoelectric body. Comprising a plurality of piezoelectric elements,
4. The biological signal detection device according to claim 1, wherein one electrode of the plurality of piezoelectric elements is electrically connected in series with a linear conductive wire as pressure transmission means. 5. . The piezoelectric element is characterized in that one electrode is formed in a flat plate shape, a piezoelectric body is provided on both surfaces of the one electrode, and the other electrode is provided on the surface of each piezoelectric body. Item 5. The biological signal detection device according to any one of Items 1 to 4. Comprising a pair of piezoelectric elements;
In these pair of piezoelectric elements, one electrode is formed in a flat plate shape, a piezoelectric body is provided on one surface of the electrode, the other electrode is provided on the surface of the piezoelectric body, and the piezoelectric body of the pair of piezoelectric elements is The biological signal detection device according to any one of claims 1 to 4, wherein the biological signal detection device is installed so as to be overlapped with the provided sides being opposed to each other. A cover member that covers and protects the piezoelectric element so that the force applied to the piezoelectric body via the pressure transmission means can be converted into electric charges with at least the tip of the pressure transmission means projecting to the outside. The biological signal detection device according to claim 1, wherein:

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