JP2008151555A - Temperature sensor, and health management system of living body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a temperature sensor for reducing a size, a weight and a power consumption. <P>SOLUTION: The temperature sensor 210T is provided with a plurality of pairs of bimetal cantilever sensors 211 whose levers 212 have gradually-different length. If a temperature rises and reaches the predetermined temperatures determined by the lengths of the levers 212 in each pair, the lever 212 contacts an electrical contact member 214, and an output signal from a detection circuit 215b is turned on in a signal processing circuit 215. If the temperature continuously rises in a sensor control section, the signal processing circuit 215 in each pair sequentially outputs the output signal turned on in order of the lengths of the levers 212. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a temperature sensor and a living body health management system using the temperature sensor.

Conventionally, the most commonly used temperature sensor elements include semiconductor piezoresistive elements and thermistor elements. In these, the electric resistance varies depending on the temperature. In order to read the resistance value, it is necessary to pass a current through the element and detect an analog value such as a voltage drop or a current value at that time. For this purpose, it is necessary to continuously pass a constant current through the element and operate it in a stable state, and as a result, a large amount of power is consumed. Further, an A / D converter circuit is required to convert an analog value into a digital signal, and power is also required for its operation.
Other temperature sensor elements include thermoelectric conversion elements such as thermocouples. Since these generate electromotive force (voltage) corresponding to temperature without consuming power, the power consumption of the element itself is zero, but the generated voltage is an analog value, so an A / D converter circuit is still necessary. And requires power.
When such a temperature sensor is wireless, securing a power source in a state where the temperature sensor is attached to a temperature measurement target becomes a problem. In addition, since power is also consumed by the A / D converter, various ideas have been made so far to reduce power consumption and extend the period in which the wireless temperature sensor can be used as much as possible. (For example, refer to Patent Document 1).

JP 2006-98398 A

However, in applications where the temperature sensor is mounted on a living body such as an animal, it is difficult to supply power from the outside or charge the battery, and the entire temperature sensor including the power supply can be downsized. Since it is necessary to reduce the weight, a large battery or the like cannot be provided. Therefore, it is necessary to further reduce power consumption in such applications.
In general, the temperature data detected by the temperature sensor is transmitted intermittently at regular intervals. However, in order to improve the responsiveness to temperature changes, the data must be detected and transmitted at finer time intervals. As a result, power consumption must be increased. In addition, when temperature is detected and transmitted intermittently, the detected temperature data is transmitted regardless of whether there is a temperature change, so it can be said that unnecessary data transmission is performed, and there is room for reducing power consumption. There is.
The present invention has been made based on such a technical problem, and an object of the present invention is to provide a temperature sensor or the like capable of reducing power consumption while enabling reduction in size and weight. .

  The inventors of the present invention, which have intensively studied to solve the above problems, have paid attention to a temperature switch using a bimetal structure. The temperature switch using the bimetal structure has zero power consumption and the output is also an ON / OFF electrical switch, so it can be read directly as a digital signal. Can be minimized. However, since the bimetal temperature switch is a switch that operates at a specific temperature, it cannot be used for detecting a continuous temperature change within a wide temperature range.

The temperature sensor of the present invention made there is a bimetallic cantilever formed by laminating two kinds of materials having different linear expansion coefficients, an electric contact member facing the tip of the cantilever with a gap, and a cantilever or electric A plurality of sets of voltage application units that apply a voltage to the contact member and a detection circuit that detects voltage fluctuation when the cantilever deformed according to the temperature change comes into contact with or separates from the electrical contact member are provided. The lengths of the plurality of sets of cantilevers or the gaps between the cantilever tips and the electrical contact members are formed to be different from each other. In this way, when the length of the multiple cantilevers or the gap between the tip of the cantilever and the electrical contact member is made different between the multiple sets, when the bimetallic cantilever is deformed according to the temperature change The timing at which the tip of the cantilever and the electrical contact member come into contact is different. The longer the cantilever is, the smaller the gap between the tip of the cantilever and the electrical contact member is, the smaller the temperature change is. In this way, when a temperature change corresponding to a temperature pitch determined according to a difference in cantilever length or a gap between the tip of the cantilever and the electrical contact member occurs between the groups, a plurality of groups The contact state between the cantilever and the electrical contact member changes, and the detection circuit can detect the contact (or separation) by voltage fluctuation. Thereby, temperature detection in a wide temperature range can be performed digitally by using a plurality of cantilevers.
Therefore, such a temperature sensor may further include a measurement control circuit that digitally measures the temperature based on signals emitted from a plurality of detection circuits.

By the way, it is preferable that the cantilever is formed of a conductive material at least on the side facing the electric contact member.
When the layer facing the electrical contact member of the cantilever is formed of a non-conductive material, the surface of the cantilever facing the electrical contact member is made of a conductive material and the cantilever is deformed in response to temperature deformation. It is preferable to provide a conducting member such as a wiring conducting to the electrical contact member.

  Further, the voltage application unit can be a capacitor fed from a power source. In such a configuration, it is not necessary to constantly apply a voltage, and the capacitor is discharged when the cantilever comes into contact with the electrical contact member, whereby the voltage change can be detected by the detection circuit. Then, when the capacitor is discharged, the power supply control circuit may perform power supply from the power source to the capacitor.

By the way, the temperature sensor as described above may be used for any purpose, but can be used for the purpose of health management of a living group such as an animal.
Recently, interest in “food safety” has been rapidly increasing due to the occurrence of BSE in Japan and the avian influenza epidemic. However, these problems cannot be fundamentally solved by symptomatic measures against individual infectious diseases from the viewpoint of “safety for human beings”. What is food? There is an urgent need to re-examine the problem from a global perspective, such as how it should be.

  As conventional methods for investigating the ecology of animals, there are known attempts to detect the estrus from the location of migratory birds using a GPS terminal and the walking frequency of cattle. In addition, offline biopsy techniques have mainly been developed for conventional animal health management sensing. However, these methods cannot perform inspection quickly, are expensive, and cannot be widely used in general.

Therefore, the inventors attach a sensor for measuring physical quantities such as acceleration, inclination, temperature, blood flow, blood pressure, and pulse to a living body such as an animal to be managed, and use the measurement result data transmitted from the sensor as data. Based on this, we have developed a technology for determining the health state of a living body by determining the behavioral state of the living body.
In such a technique, a physical sensor, a communication device, and the like can be contained in an ultra-small chip by the MEMS technique. By attaching such a chip to a large number of management organisms, collecting data sequentially, and analyzing the data using a computer, it is possible to manage a large number of management organisms at once.

In the course of further research, the present inventors have found that it is preferable to monitor changes in the body temperature of the living body in order to determine the health state of the living body.
The temperature sensor of the present invention is suitable for use as described above.
The living body health management system for such a use is a system for managing the health of the living body, is mounted on the living body to be managed, measures a physical quantity including at least temperature, and wirelessly transmits the measurement result as data. A sensor and a control device that determines whether or not an abnormality has occurred in the health state of the living body based on data transmitted from the sensor. The sensor includes a bimetallic cantilever formed by laminating two kinds of materials having different linear expansion coefficients, an electric contact member facing the tip of the cantilever with a gap, and a voltage applied to the cantilever or the electric contact member. A plurality of sets of voltage applying units to be applied and detection circuits for detecting voltage fluctuations when the cantilever deformed in response to a temperature change comes into contact with or away from the electrical contact member; The gap between the tip of the cantilever and the electrical contact member is formed to be different from each other.
Here, the sensor preferably includes a remote power storage unit that stores the wirelessly supplied power.

According to the temperature sensor of the present invention, it is possible to digitally measure the temperature change by detecting the contact of the plurality of cantilevers provided to the electrical contact member with a signal from the detection circuit. At this time, it is possible to perform temperature measurement in a wide temperature range by appropriately setting the difference in cantilever length between each pair or the difference in gap between the tip of the cantilever and the electrical contact member, Without detecting the temperature with the minimum unit / accuracy more than necessary, the power consumption can be minimized. Further, unless the temperature change amount exceeds a certain level, the cantilever does not come into contact with the electrical contact member and the ON signal is not output, so that the power for outputting the signal can be suppressed. As a result of performing the measurement in this manner, if the temperature change is small, the amount of data transmitted wirelessly can be suppressed, which also leads to power saving.
In addition, voltage fluctuations that occur when the cantilever is brought into contact with or separated from the electrical contact member directly becomes an output signal from the detection circuit, so that a digital signal can be directly output, and an AD converter is not required.
Such a temperature sensor can be formed in a small size by the MEMS technology, and by reducing power consumption, it is possible to eliminate the battery and reduce the weight.
In addition, in a living body health management system equipped with such a temperature sensor, the sensor can be reduced in weight and the life can be increased by suppressing power consumption. Although it is not intended to limit the above, it is particularly suitable for the purpose of performing health care particularly on animals and the like whose behavior is difficult to control.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings. In the present embodiment, an example will be given in which the present invention is used for monitoring the occurrence of avian influenza.
FIG. 1 is a diagram conceptually illustrating a bird flu monitoring system (biological health management system) 100 according to the present invention.
As shown in FIG. 1, one or more avian influenza monitoring systems 100 are installed to cover a sensor 120 attached to a bird (living body) managed in the management area 110 and the management area 110. The relay station 130 includes a relay station controller 140 that centrally controls all the relay stations 130 installed in the management area 110, a transmission / reception device 150, a control device (determination device) 160, and the like.

In this embodiment, the management area 110 is provided for raising birds such as a birdhouse. When the present invention is applied in addition to bird flu monitoring, the management area 110 may be an outdoor area such as a ranch, an indoor area such as a cowshed, or each animal in the zoo. It can be a building or a whole natural park. Furthermore, the configuration of the present invention can be applied even to a human subject.
In the management area 110, the sensor 120 and the relay station 130 communicate with each other wirelessly. Therefore, the management area 110 is an area where the relay station 130 can directly or indirectly acquire the signal from the sensor 120. Therefore, when the management area 110 is widened, the output of the wireless communication of the sensor 120 may be increased or the number of relay stations 130 may be increased. It is preferable that one relay station 130 can cover an area having a radius of several tens of meters. As a communication method between the sensor 120 and the relay station 130, there are standards such as IEEE 802.11x wireless LAN, PHS (registered trademark), Bluetooth (registered trademark), ZigBee (registered trademark), and UWB. Considering the balance between power consumption and communication distance, ZigBee (registered trademark) can be said to be a suitable method at present. Of course, other methods may be used.

The sensor 120 is a system for monitoring the health state of a bird, which is a high-density integration of a sensor group that detects the posture, behavior, vital signs, and the like of a bird and a detection processing circuit, a communication circuit, a power source, and a power management device. It is a package.
Measurement data in the sensor 120 is transmitted wirelessly. The transmitted measurement data is received by the relay station 130 and further transferred to the relay station controller 140.

The relay station 130 and the relay station controller 140 can be connected by wireless or wired Ethernet (registered trademark). The relay station controller 140 controls not only the relay station 130 installed in the management area 110 but also the relay stations in the other management areas 112 and 114, and collects and transmits data of the sensors 120 received by these relay stations. Transfer to device 150. Further, in addition to collecting data from the relay station 130, the relay station controller 140 is assigned an identification mark such as an IP address to all the relay stations 130 installed in the management area 110, or from the control device 160. A function of mediating transmission of a command given to each sensor 120 can be added. In another embodiment, when a mesh network is formed by a plurality of relay stations 130, the relay station controller 140 may be configured to also control handover between the relay stations 130.
The transmission / reception device 150 transmits the measurement data of the sensor 120 to the control device 160 through Ethernet (registered trademark), the Internet, a telephone line, a wireless telephone network, or the like.

The control device 160 is a computer device in terms of hardware, and can be manufactured by installing software having necessary functions in a general-purpose computer. For this reason, many functions of the control device 160 are realized by the cooperation of hardware such as a CPU, memory, network adapter, and modem provided in a general computer and software.
The control device 160 monitors the occurrence of avian influenza by determining the measurement data transmitted from the sensor 120. If it is determined that the measurement data transmitted from the sensor 120 indicates the occurrence of avian influenza, the determination result, that is, information indicating that avian influenza has occurred, is output as an alarm, printed matter It is also possible to output by printing out, sending an e-mail to a destination input in advance, or the like. The control device 160 may be installed in the vicinity of the management area 110, but may be installed in a remote place that is completely separated.

Next, the configuration of the sensor 120 will be described with reference to FIG.
FIG. 2 is a diagram illustrating the configuration of the sensor 120.
As shown in FIG. 2, the sensor 120 includes, for example, a physical quantity sensor 210 that measures a predetermined physical quantity on a thin film substrate, and a circuit that controls each unit so as to perform a predetermined operation as the sensor 120. Communication control for transmitting and receiving radio waves between the configured sensor control unit (power supply control circuit, measurement control circuit) 220, the capacitor unit 230 that stores power necessary for the operation of the sensor 120, and the relay station 130 is performed. This is an ultra-small network sensor chip in which a communication control unit 240 and an antenna 250 are mounted on a thin-band (film-like) substrate.
Such a sensor 120 is miniaturized by making full use of the latest ultra-high density mounting technology and MEMS processing technology and narrowing down the sensor function. In one example, an ultra-small sensor chip is manufactured by a system-in-package in which a three-dimensional laminated chip (5 mm or less) is mounted in the middle 1 cm square region on a 3 cm square antenna FPC.

  The physical quantity sensor 210 is a physical quantity sensing chip that measures at least temperature. In the present embodiment, as the physical quantity sensor 210, an acceleration sensor 210A and a temperature sensor 210T are provided.

  In the sensor 120 of the present embodiment, sensor information including acceleration information and temperature information detected by the acceleration sensor 210A and the temperature sensor 210T is not sequentially transmitted to the relay station 130, but the transmission frequency and the amount of transmission data are suppressed. Thus, the power consumption can be reduced.

Specifically, the sensor control unit 220 includes an IC and a memory, and includes an event-driven circuit that performs predetermined processing when a signal is received from the physical quantity sensor 210. Here, as the predetermined processing, there is a method of storing the contents of the signal received from the physical quantity sensor 210 in a memory.
Further, in the present embodiment, sensor 120 receives electric waves transmitted from relay station 130 by antenna 250, generates electric power by induced electromotive force, and stores this electric power in capacitor unit 230. . Therefore, the sensor control unit 220 includes an RF-DC conversion circuit that converts radio waves received by the antenna 250 into direct current, a charging circuit that stores electric power in the capacitor unit 230 by direct current converted by the RF-DC conversion circuit, It has. As described above, since the sensor 120 is an active sensor that is equipped with a power source and communicates with its own power, scanning by a reader is not required unlike RF-ID, and it is never easy to control its behavior. Suitable for bird management.

  The communication control unit 240 responsible for communication control functions as an ultra-small wireless communication device for transmitting measurement data from the physical quantity sensor 210, and transmits and receives radio waves to and from a control chip having a communication control circuit. And an impedance matching circuit for matching the impedances of the two. Here, the control chip is configured to have a unique identifier. When transmitting sensor information from the physical quantity sensor 210, the control chip is configured to transmit the identifier together.

FIG. 3 is a diagram showing a configuration of a temperature sensor 210T for detecting the temperature in the physical quantity sensor 210. As shown in FIG.
As shown in FIG. 3, the temperature sensor 210 </ b> T includes a plurality of bimetal cantilever sensors 211.
In the bimetal cantilever sensor 211, a lever (cantilever) 212 made of a bimetal material in which a high linear expansion coefficient material 212a and a low linear expansion coefficient material 212b are joined or laminated is fixed to the base 213 only at the base end 212c. Thus, the structure is supported in a cantilever shape. An electric contact member 214 made of a conductive material is disposed with a predetermined gap so as to face the lever 212.

Examples of the high linear expansion coefficient material 212a constituting the lever 212 include Al (α = 23.1E-6 / ° C.), Au (α = 14.2E-6 / ° C.), Ni (α = 13.4E−). 6 / ° C.) can be used. As the low linear expansion coefficient material 212b, for example, W (α = 4.5E-6 / ° C.), Mo (α = 5.5E-6 / ° C.), Invar alloy (α = 0.1E-6 / ° C.) Silicon (α = 2.5E-6 / ° C.), silicon oxide (α = 0.5E-6 / ° C.), silicon nitride (α = 3E-6 / ° C.), or the like can be used.
The lever 212 made of such a bimetal material is bent and deformed around the base end portion 212c according to a change in temperature due to the difference in linear expansion coefficient between the high linear expansion coefficient material 212a and the low linear expansion coefficient material 212b. When the tip end 212d moves in a direction approaching / separating from the electrical contact member 214 and reaches a predetermined temperature, the tip end 212d comes into contact with the electrical contact member 214.
Here, in the measurement at a temperature higher than room temperature, the low linear expansion coefficient material 212b is usually provided so as to face the electric contact member 214, and constitutes an electric contact with respect to the electric contact member 214. For this reason, the low linear expansion coefficient material 212b needs to be formed of a conductive material. When a material other than metal is used as the low linear expansion coefficient material 212b, it is necessary to add a conductive member such as a wiring made of a conductive material to the surface of the lever 212 on the low linear expansion coefficient material 212b side.

In the plurality of bimetal cantilever sensors 211 provided, the lengths of the levers 212 are different from each other. If the high linear expansion coefficient material 212a and the low linear expansion coefficient material 212b constituting the lever 212 are common between the bimetal cantilever sensors 211, the lever 212 should be at the same distance from the base end portion 212c. For example, it bends and deforms with the same radius of curvature according to the temperature change. At this time, since the lengths of the levers 212 are different between the bimetal cantilever sensors 211, the longer the lever 212, the greater the displacement of the tip end portion 212d. Therefore, as the bimetal cantilever sensor 211 having the longer lever 212, the tip end portion 212d contacts the electrical contact member 214 at an earlier timing. That is, in each bimetal cantilever sensor 211, the timing, that is, the temperature at which the tip 212 d contacts the electrical contact member 214 is determined according to the length of the lever 212.
Here, as will be described in detail later, the difference in the length of the lever 212 between the bimetal cantilever sensors 211 is determined by the measurement pitch when the temperature is measured digitally, in other words, the minimum unit of measurement. Accordingly, the length of the lever 212 between the bimetal cantilever sensors 211 is preferably provided at a constant pitch. Here, the length of the lever 212 may be constant, and the gap between the lever 212 and the electrical contact member 214 may be different among the plurality of bimetal cantilever sensors 211.

In each bimetal cantilever sensor 211, a voltage is applied to the electrical contact member 214, and the lever 212 side is grounded.
A signal processing circuit 215 is connected to each bimetal cantilever sensor 211. In the signal processing circuit 215, the voltage stored in the capacitor (voltage application unit) 215 a is applied to the electrical contact member 214. In the bimetal cantilever sensor 211, when the lever 212 is deformed due to a temperature change and is brought into contact with the electrical contact member 214 to be conductive, the voltage changes. This is detected by a detection circuit 215b composed of an F / F (Flip Flop) circuit. Detect with. When the voltage detected by the detection circuit 215b fluctuates, the output signal from the detection circuit 215b switches from OFF to ON, or from ON to OFF.
In the sensor control unit 220, when it is detected that the output signal from the detection circuit 215b has switched from OFF to ON, after a certain waiting time has elapsed, the lever 212 and the electrical contact member 214 are discharged due to conduction. A power supply control signal for performing power supply from the power source for a predetermined time is output to the power source to the capacitor 215a.
Such a signal processing circuit 215 can be formed in an IC constituting the sensor control unit 220.

In the temperature sensor 210T having such a configuration, a plurality of sets of bimetal cantilever sensors 211 are provided, and the lengths of the levers 212 are different in a plurality of stages. Thus, for example, when the temperature rises and reaches a predetermined temperature determined by the length of the lever 212 of each bimetal cantilever sensor 211, the lever 212 contacts the electric contact member 214 and the signal processing circuit 215 detects from the detection circuit 215b. Output signal is turned ON. Thereby, in the sensor control unit 220, for example, when the temperature rises continuously, an ON output signal is sequentially output from each pair of signal processing circuits 215 in the order of the length of the lever 212. Conversely, if the temperature decreases, the lever 212 that has been in contact with the electrical contact member 214 is separated from the electrical contact member 214, and the output signal from the detection circuit 215b is turned off. For this reason, in the sensor control unit 220, for example, when the temperature continuously decreases, output signals of OFF are sequentially output from the signal processing circuits 215 of each set in the shortest order of the lever 212.
Here, in the sensor control unit 220, when the signal from the detection circuit 215b is switched from OFF to ON, or from ON to OFF, the fact that the signal has been switched from OFF to ON or from ON to OFF and the time information is stored in the memory. The stored information is transmitted to the control device 160 via the relay station 130 at a predetermined timing.

With such a configuration, the temperature change can be measured digitally by detecting the contact of the plurality of bimetallic levers 212 having different lengths to the electrical contact member 214 with a signal from the detection circuit 215b. It becomes possible. At this time, by appropriately setting the difference in the length of the lever 212 among the plurality of levers 212, the temperature is not detected with a minimum unit / accuracy more than necessary, and the power consumption is minimized. It can be. As long as the temperature change amount does not exceed a certain level, the lever 212 does not contact the electrical contact member 214 and no ON signal is output. Thereby, naturally, the power for outputting the signal can also be suppressed. Further, the data obtained as a result of the measurement in this way is the temperature and time information when the temperature change occurs. That is, if the temperature change is small, the amount of data transmitted wirelessly can be suppressed, which also leads to power saving.
Even during standby, power is stored in the capacitor 215a, and power is supplied to the capacitor 215a when the lever 212 comes into contact with the electrical contact member 214 and discharges. Can be suppressed. Furthermore, since the voltage fluctuation generated when the lever 212 contacts / separates from the electric contact member 214 becomes the output signal from the detection circuit 215b as it is, a digital signal can be directly output, and an AD converter is unnecessary. .

Such a temperature sensor 210T can be formed by MEMS technology.
As shown in FIG. 4, a silicon oxide film 261 serving as a sacrificial layer is deposited on a silicon substrate 260, and Ni (Young's modulus 200 GPa) having a thickness of 0.5 μm is formed thereon as a high linear expansion coefficient material 222a. , Linear expansion coefficient 13.4E-6 / ° C.) The film 262 is formed by sputtering or vapor deposition. Further, a W (Young's modulus: 345 GPa, linear expansion coefficient: 4.5E-6 / ° C.) film 263 having a thickness of 0.5 μm is formed as a low linear expansion coefficient material 222b by sputtering or vapor deposition. Form. These films can be processed with an accuracy of μm level using photolithography and etching. 21 levers 222 having a length of 195 μm to 215 μm are manufactured by changing the length by 1 μm. By using photolithography and etching, a plurality of levers 222 having different lengths can be manufactured simultaneously.
Next, etching is performed with an HF aqueous solution to remove the silicon oxide film 261 at a lower portion of the lever 222 having the bimetal structure, so that the lever 222 can be freely operated. Since W and Ni do not dissolve in HF, the lever 222 can be left selectively.
A glass plate 264 having a recess 264a having a depth of 5 μm is joined to the upper surface of the lever 222, and an electrical contact member 224 is joined to the inside thereof. The glass plate 264 and the electrical contact member 224 may be obtained by joining two layers of an insulating spacer having a thickness of 5 μm and a substrate on which an electrode is formed.
The bimetal lever 222 is bent toward the electrical contact member 224 when the temperature rises because the W film 263 made of the low linear expansion coefficient material 222b faces the electrical contact member 224. Here, one end of a bimetal prepared by superposing two layers of material A (thickness ta, Young's modulus Ea, linear expansion coefficient αa) and material B (thickness tb, Young's modulus Eb, linear expansion coefficient αb) is fixed. When the cantilever structure has a length L, the displacement y due to the temperature change ΔT at the other end is expressed by the following equation. From this equation, the temperature difference that produces a displacement of 5 μm at the tip 222 d of the lever 222 can be calculated.

FIG. 5 shows a calculation result when the lever 212 has a length of 195 to 215 μm in the temperature sensor 210T configured as described above using Equation 1.
When the lever 212 without bending at room temperature (20 ° C.) is manufactured, when the temperature difference shown in FIG. 5 occurs, the lever 212 and the electrical contact member 214 come into contact with each other and the switch is turned on. For example, the lever 212 having a length of 215 μm is turned on at a temperature difference of 16.51 ° C. (actual temperature 36.51 ° C.) with respect to room temperature. The 21 levers 21 having different lengths can cover the actual temperature range of 36.51 ° C to 40.07 ° C at intervals of about 0.2 ° C. By using this temperature sensor 210T, the body temperature can be measured with an accuracy (measurement pitch) of 0.2 ° C.
When the sensor 120 is used for another living body, the same design may be performed in the measurement temperature range corresponding to the type of the living body.

  Thus, the temperature sensor 210T can be reduced in size and weight by forming the temperature sensor 210T by the MEMS technology. Moreover, since the levers 212 and the like having different lengths can be formed in a lump, they can be mass-produced at low cost. The sensor 120 provided with such a temperature sensor 210T can be reduced in size and weight, and can save power.

The preferred embodiments of the present invention have been described above by way of examples. However, the present invention can take various embodiments in addition to the embodiments described herein without departing from the scope thereof. Needless to say.
For example, the sensor 120 may be designed exclusively for size, type of sensor, output of the communication device, etc., depending on the application, such as for bird farming, pastoral use, and wild animals.
The sensor 120 can also be used for purposes other than monitoring the occurrence of avian influenza. In addition, if the animal is not an animal whose operation is difficult to control and is used for other purposes, the sensor 120 may be provided with a battery instead of supplying power by radio waves. Of course, the battery can be charged at an appropriate timing.
The present invention can be applied not only to the aquaculture industry, but also to other livestock farming and health monitoring of wild animals, and prevents large-scale transmission of infectious diseases via wild animals. It can also be used to construct a simple network.
In addition to this, as long as it does not depart from the gist of the present invention, the configuration described in the above embodiment can be selected or changed to another configuration as appropriate.

It is a conceptual diagram of the bird flu monitoring system in this Embodiment. It is a figure which shows the structure of a sensor. It is a figure which shows the specific structure of a temperature sensor. It is an example of a structure in the case of manufacturing a temperature sensor by MEMS technology. It is a figure which shows the relationship between the length of a cantilever and an operating temperature difference.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Bird flu monitoring system (biological health management system), 120 ... Sensor, 130 ... Relay station, 150 ... Transmission / reception device, 160 ... Control device (determination device), 210 ... Physical quantity sensor, 210A ... Acceleration sensor, 210T ... Temperature Sensors 211... Bimetal cantilever sensor 212... Lever (cantilever) 212 a. High linear expansion coefficient material 212 b. Low linear expansion coefficient material 212 c. Base end section 212 d. Signal processing circuit, 215a ... capacitor (voltage application unit), 215b ... detection circuit, 220 ... sensor control unit (power feeding control circuit, measurement control circuit), 240 ... communication control unit, 250 ... antenna

Claims (8)

A bimetallic cantilever formed by laminating two kinds of materials having different linear expansion coefficients;
An electrical contact member facing the tip of the cantilever with a gap therebetween,
A voltage application unit that applies a voltage to the cantilever or the electrical contact member;
A plurality of detection circuits that detect voltage fluctuations when the cantilever deformed in response to a temperature change comes into contact with or separates from the electrical contact member;
A temperature sensor characterized in that a plurality of sets of cantilevers have different lengths or gaps between the cantilever tips and the electrical contact members.   2. The temperature sensor according to claim 1, wherein the cantilever has at least a layer facing the electric contact member formed of a conductive material.   The cantilever is formed of a conductive material on a surface facing the electric contact member, and a conductive member that conducts to the electric contact member when the cantilever is deformed in response to temperature deformation is provided. The temperature sensor according to claim 1. The voltage application unit is a capacitor fed from a power source,
4. The power supply control circuit according to claim 1, further comprising a power supply control circuit configured to supply power from the power source to the capacitor when the cantilever comes into contact with the electrical contact member and the capacitor is discharged. 5. The temperature sensor described in 1.   The temperature sensor according to any one of claims 1 to 4, further comprising a measurement control circuit that digitally measures the temperature based on signals emitted from the plurality of detection circuits.   The detection circuit detects a voltage variation when the cantilever is in contact with or separated from the electrical contact member, so that the length of the cantilever between the pairs or the tip of the cantilever and the electrical contact member 6. The temperature sensor according to claim 5, wherein a signal is output only when a temperature change corresponding to a temperature pitch determined by a gap between and a temperature pitch occurs. A system for managing the health of a living body,
A sensor that is mounted on the living body and measures a physical quantity including at least temperature, and wirelessly transmits a result of the measurement as data;
A determination device that determines whether an abnormality has occurred in the health condition of the living body based on the data transmitted from the sensor;
The sensor is
A bimetallic cantilever formed by laminating two kinds of materials having different linear expansion coefficients;
An electrical contact member facing the tip of the cantilever with a gap therebetween,
A voltage application unit that applies a voltage to the cantilever or the electrical contact member;
A plurality of detection circuits that detect voltage fluctuations when the cantilever deformed in response to a temperature change comes into contact with or separates from the electrical contact member;
A living body health management system, wherein a plurality of sets of the cantilevers have different lengths or gaps between the cantilever tips and the electrical contact members.   The living body health management system according to claim 7, wherein the sensor includes a remote power storage unit that stores wirelessly supplied power.

Images