Temperature measuring device

Abstract

This temperature measurement device (102) comprises a sensor unit (1) for measuring the magnitude of a thermal flow transmitted from a living body (100), and an electronic circuit unit (2) for calculating the internal temperature of the living body (100) on the basis of the measured magnitude of the thermal flow. The sensor unit (1) is provided with a hollow-structure heat-transmitting body (10) positioned such that the peripheral edge thereof is in contact with the living body, a cover member (11) positioned so as to fill a space between the living body (100) and the heat-transmitting body (10), a detection unit (18) provided to the cover member (11) so as to measure the magnitude of the thermal flow transmitted from the living body (100), and a cover member (14) positioned so as to cover the heat-transmitting body (10).

Description

[Technical field]

[0001] The present invention relates to a temperature measuring device for measuring the internal temperature of a living body non-invasively and with high accuracy. [Background technology]

[0002] Conventionally, there have been known techniques for non-invasively measuring the deep body temperature of a living body. For example, Non-Patent Document 1 discloses a technique for estimating the deep body temperature of a living body by assuming a pseudo one-dimensional model of the outside air and the living body.

[0003] In the technique disclosed in Non-Patent Document 1, a one-dimensional model of heat transfer between a living body 100 and a sensor 101 is assumed as shown in FIG. body In Figure 1, T air is the outside air temperature, H signal is the heat flux entering the sensor 101, R air is the heat flux H signal Thermal resistance when moving to the outside air, T skin is the temperature of the skin surface of the living body 100 measured by the sensor 101, and T t is the temperature of the top surface of the sensor 101 opposite to the surface in contact with the living body 100. body can be estimated using equation (1). T body =T skin +R sensor ×H signal (1)

[0004] Proportionality coefficient R sensor is the deep temperature T measured using a tympanic thermometer at the start or during the measurement, a rectal temperature measured using a rectal thermometer, or an axillary temperature measured using a clinical thermometer. body By substituting (reference temperature) into equation (1), the following equation can be obtained. R sensor =(T body -T skin ) / (T skin -T t ) ···(2)

[0005] Therefore, the skin surface temperature T skin and the heat flux H flowing into the sensor 101 signal By measuring the temperature, the deep body temperature T body can be estimated. However, when a one-dimensional model is assumed as a heat transfer model for the living body 100 as in the technology disclosed in Non-Patent Document 1, the generation of wind or a change in the outside air temperature causes a heat flux H , which is a heat flux that should flow into the sensor 101, to deviate from the intended flow and move in a lateral direction as shown in FIG. Leak The thermal resistance between the sensor 101 and the outside air changes due to wind and the outside air temperature, and a heat flux H Leak When this occurs, the heat flux that should be measured changes to H signal From H' signal decreases to.

[0006] As described above, when the living body 100 is exposed to wind or the outside air temperature changes, the one-dimensional model of heat transfer is no longer valid. For this reason, in the conventional technology, the deep body temperature T body However, there was a problem that errors could occur in the estimation of the [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] H.-C. Gunga,et al.,“The Double Sensor.A non-invasive device to continuously monitor core temperature in humans on earth and in space”,Respiratory Physiology & Neurobiology,2009 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made to solve the above-mentioned problems, and aims to provide a temperature measuring device that can suppress changes in thermal resistance between the sensor and the outside air and accurately measure the internal temperature of a living body. [Means for solving the problem]

[0009] The temperature measuring device of the present invention comprises a sensor unit configured to measure the magnitude of heat flow transmitted from a living organism, and an electronic circuit unit configured to calculate the internal temperature of the living organism based on the magnitude of the heat flow measured by the sensor unit, and the sensor unit comprises a hollow heat conductor arranged so that its peripheral portion is in contact with the living organism, a first covering material arranged to fill the space between the living organism and the heat conductor, a detection unit provided on the first covering material to measure the magnitude of the heat flow transmitted from the living organism, and a second covering material arranged to cover the heat conductor.

[0010] In one configuration example of the temperature measuring device of the present invention, the electronic circuit section is provided inside the second covering material next to the sensor section. In one configuration example of the temperature measuring device of the present invention, the electronic circuit section is provided inside the second covering material on the sensor section. Moreover, one configuration example of the temperature measuring device of the present invention is characterized in that it further comprises a housing provided so as to cover the second covering material on the outside.

[0011] In addition, in one configuration example of the temperature measuring device of the present invention, the detection unit is composed of a first temperature sensor provided on a surface of the first covering material facing the living body and configured to measure the temperature of the surface of the living body, and a second temperature sensor configured to measure the temperature inside the first covering material directly above the first temperature sensor, and the electronic circuit unit calculates the internal temperature of the living body based on the measurement results of the first and second temperature sensors. In addition, in one configuration example of the temperature measuring device of the present invention, the detection unit is composed of a temperature sensor provided on the surface of the first covering material facing the living organism and configured to measure the temperature of the surface of the living organism, and a heat flux sensor provided on the surface of the first covering material facing the living organism and configured to measure the heat flux flowing from the living organism into the sensor unit, and the electronic circuit unit calculates the internal temperature of the living organism based on the measurement results of the temperature sensor and the heat flux sensor. Effect of the Invention

[0012] According to the present invention, by providing a thermal conductor away from the detection unit, heat from the living body can be transported via the thermal conductor and the temperature of the upper part of the detection unit can be raised, thereby suppressing the lateral heat flow rate that deviates from the pseudo-one-dimensional model between the outside air and the living body. Therefore, even if the temperature around the sensor unit changes or wind is blowing, the internal temperature of the living body can be measured accurately. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing the configuration of a temperature measuring device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is an external view of the temperature measuring device according to the first embodiment of the present invention. [Diagram 3] FIG. 3 is a partially cutaway perspective cross-sectional view of a thermal conductor according to a first embodiment of the present invention. [Figure 4] FIG. 4 is a flowchart illustrating the operation of the temperature measuring device according to the first embodiment of the present invention. [Figure 5A-5D] 5A to 5D are diagrams showing examples of how the temperature measuring device according to the first embodiment of the present invention is attached to a living body. [Figure 6A-6C] 6A to 6C are diagrams showing examples of how the temperature measuring device according to the first embodiment of the present invention is attached to a living body. [Figure 7] FIG. 7 is a graph showing the deep body temperature estimated by the temperature measuring device according to the first embodiment of the present invention and the tympanic membrane temperature measured by a tympanic membrane thermometer. [Figure 8] FIG. 8 is a diagram showing changes over time in the deep body temperature estimated by the temperature measuring device according to the first embodiment of the present invention and the tympanic membrane temperature measured by a tympanic membrane thermometer. [Figure 9] FIG. 9 is a diagram showing the configuration of a temperature measuring device according to a second embodiment of the present invention. [Figure 10] FIG. 10 is an external view of a temperature measuring device according to a second embodiment of the present invention. [Figure 11] FIG. 11 is a flowchart illustrating the operation of the temperature measuring device according to the second embodiment of the present invention. [Figure 12] FIG. 12 is a diagram showing the configuration of a temperature measuring device according to a third embodiment of the present invention. [Figure 13] FIG. 13 is an external view of a temperature measuring device according to a third embodiment of the present invention. [Figure 14] FIG. 14 is a diagram showing the configuration of a temperature measuring device according to a fourth embodiment of the present invention. [Figure 15] FIG. 15 is an external view of a temperature measuring device according to a fourth embodiment of the present invention. [Figure 16] FIG. 16 is a block diagram showing an example of the configuration of a computer that realizes the temperature measuring device according to the first to fourth embodiments of the present invention. [Figure 17] FIG. 17 is a diagram showing a thermal equivalent circuit model of a living body and a sensor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] [First Example] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a diagram showing the configuration of a temperature measuring device according to a first embodiment of the present invention, and Fig. 2 is an external view of the temperature measuring device. The temperature measuring device 102 includes a sensor unit 1 that measures the magnitude of heat flow transmitted from a living body 100, and a deep body temperature T body and an electronic circuit section 2 that calculates the internal temperature.

[0015] The sensor unit 1 is arranged so that the peripheral portion thereof is in contact with the living body 100, and includes a hollow heat conductor 10 that transports the heat flux from the living body 100 to the upper portion of the sensor unit 1, a covering material 11 that is arranged so as to fill the space between the living body 100 and the heat conductor 10, and a skin surface temperature T skin and a temperature sensor 12 measuring the temperature T t The device is equipped with a temperature sensor 13 that measures the heat flow, a covering material 14 that is arranged to cover the thermal conductor 10, and a housing 15 that houses the thermal conductor 10, the covering materials 11 and 14, and the temperature sensors 12 and 13. The temperature sensors 12 and 13 constitute a detection unit 18 that measures the magnitude of the heat flow.

[0016] The electronic circuit unit 2 includes a memory unit 20 for storing data, and a temperature sensor 12 for detecting the deep body temperature T body A calculation unit 21 for calculating the deep body temperature T body The device is equipped with a communication unit 22 that transmits the data to an external terminal, a control unit 23 that controls reading and writing of data to the memory unit 20 and communication, a power supply unit 24 that supplies power to the memory unit 20, the calculation unit 21, the communication unit 22, and the control unit 23, and a housing 25 that houses the memory unit 20, the calculation unit 21, the communication unit 22, the control unit 23, and the power supply unit 24.

[0017] The sensor unit 1 is attached so that the covering material 11 and the thermal conductor 10 are in contact with the skin of the living body 100. For example, it is preferable to attach the sensor unit 1 to the living body 100 using double-sided tape or silicone rubber that has excellent biocompatibility. As the temperature sensors 12 and 13, for example, a thermistor, a thermocouple, a platinum resistor, an IC (Integrated Circuit) temperature sensor, etc. can be used.

[0018] The temperature sensor 13 is disposed directly above the temperature sensor 12. If the distance between the temperature sensors 12 and 13 changes during measurement, the proportionality coefficient R sensor changes, and the deep body temperature T bodySince an error occurs in the estimation of the temperature, the temperature sensors 12 and 13 are supported by a covering material 11. Considering the leakage of heat, it is necessary to use a material for the covering material 11 that has a smaller thermal conductivity than the thermal conductor 10. The thermal conductivity of the living body 100 (0.2 to 0.5 W / m 2 It is preferable to use a material with a thermal conductivity similar to that of the

[0019] Furthermore, the covering material 11 maintains the relative positional relationship between the thermal conductor 10 and the temperature sensors 12, 13. Fig. 3 is a partially cutaway perspective cross-sectional view of the thermal conductor 10. The thermal conductor 10 has a truncated cone shape with an area of ​​the top surface away from the living body 100 smaller than the area of ​​the bottom surface on the living body 100 side. The material constituting the thermal conductor 10 is preferably one with high thermal conductivity to efficiently transport heat flux. For example, the thermal conductor 10 can be made of a metal such as aluminum.

[0020] In addition to metal, the material of the thermal conductor 10 may be a resin containing metal, graphite, carbon nanotubes, or the like, or a material in which metal fibers are woven into a predetermined shape. By orienting graphite or carbon nanotubes in the plane of a sheet-like resin, the thermal conductor 10 can be realized with thermal conductivity anisotropy, in which the thermal conductivity in the in-plane direction perpendicular to the thickness direction is higher than the thermal conductivity in the thickness direction, and with flexibility. A liquid such as grease containing graphite, carbon nanotubes, or metal may be used as the thermal conductor 10. As illustrated in Figs. 1 and 3, a through hole 16 may be formed in the top surface of the thermal conductor 10.

[0021] When the thermal conductor 10 is sufficiently large relative to the temperature sensors 12 and 13, the peripheral portion of the thermal conductor 10 in contact with the living body 100 is disposed at a position sufficiently distant from the temperature sensors 12 and 13, so that the heat flux from the living body 100 is collected by the thermal conductor 10 outside the temperature sensors 12 and 13 and transported to the top surface of the thermal conductor 10. In this manner, the thermal conductor 10 efficiently transports the heat flux from the living body 100 upward outside the temperature sensors 12 and 13, thereby suppressing the heat flux that deviates from the temperature sensors 12 and 13 and flows out to the outside air. The effect of the thermal conductor 10 in suppressing the heat flux that deviates from the temperature sensors 12 and 13 and flows out to the outside air is highest at a position near the center line (L in FIG. 3). Therefore, it is desirable to place the temperature sensors 12 and 13 near the center line L of the thermal conductor 10.

[0022] As described above, the through-hole 16 may be formed in the top surface of the thermal conductor 10. By appropriately adjusting the size of the through-hole 16, the deep body temperature T body It is possible to adjust the measurement depth when measuring the temperature of the thermal conductor 10. However, providing the through hole 16 in the thermal conductor 10 is not an essential component of the present invention.

[0023] The material of the covering material 14 may be the same as that of the covering material 11. The material of the housings 15 and 25 may be the same as that of the covering materials 11 and 14. The covering materials 11 and 14 and the housings 15 and 25 may be made of almost any resin material.

[0024] If flexible materials are used for the covering materials 11 and 14, the thermal conductor 10, and the housing 15, they can be deformed to fit the complex shape of the living body 100. Similarly, if the electronic circuit unit 2 is mounted on a flexible substrate such as polyimide and a flexible material is used for the housing 25, they can be deformed to fit the shape of the living body 100. This makes it easy to attach the sensor unit 1 and the electronic circuit unit 2 to the living body 100. In addition, the feeling of wearing the sensor unit 1 and the electronic circuit unit 2 on the living body 100 can be improved.

[0025] The temperature sensors 12 and 13 are connected to the electronic circuit unit 2 by wiring 3. FIG. 4 is a flow chart for explaining the operation of the temperature measuring device 102 of this embodiment. The temperature sensor 12 detects the temperature T skin The temperature sensor 13 measures the temperature T t The measurement data of the temperature sensors 12 and 13 is temporarily stored in the storage unit 20.

[0026] The memory unit 20 stores a proportionality coefficient R sensor is stored in advance. The calculation unit 21 calculates the temperature T skin ,T t and the proportionality coefficient R sensor Based on this, the deep body temperature T of the living body 100 body is calculated, for example, by equation (3) (step S101 in FIG. 4). T body =T skin +R sensor ×(T skin -T t ) ···(3)

[0027] As shown in equation (3), T Skin -T t Calculating the heat flux H in Eq. signal This is equivalent to calculating The communication unit 22 detects the deep body temperature T body The data is transmitted to an external terminal such as a PC (Personal Computer) or a smartphone (FIG. 4, step S102). body Display the value of .

[0028] The temperature measuring device 102 performs the above-mentioned processes of steps S100 to S102 at regular time intervals, for example, until an instruction to end the measurement is received from the user (YES in step S103 in FIG. 4).

[0029] As shown in Figures 5A to 5D and 6A to 6C, the temperature measuring device 102 can be attached to various parts of the living body 100, but in any case, it is desirable for the temperature measuring device 102 to be in direct contact with the skin of the living body 100.

[0030] In the example of Fig. 5A, the temperature measuring device 102 is attached to the forehead of the living body 100 using double-sided tape for living bodies. In the example of Fig. 5B, the temperature measuring device 102 is attached to the clavicle of the living body 100.

[0031] In the examples of Fig. 5C and Fig. 5D, the temperature measuring device 102 is attached to the armpit of the living body 100 using an elastic band 103. In the example of Fig. 6A, the temperature measuring device 102 is attached to the thigh of the living body 100. In the example of Fig. 6B, the temperature measuring device 102 is attached to the upper arm of the living body 100. In the example of Fig. 6C, the temperature measuring device 102 is attached to the wrist of the living body 100. In the examples of Fig. 5C, Fig. 5D, and Fig. 6A to Fig. 6C, the band 103 is used, but the temperature measuring device 102 may be attached to the living body 100 by pressure from compression wear worn by the living body 100.

[0032] Proportional coefficient R used to estimate core body temperature sensor As mentioned above, the proportionality coefficient R can be calculated in advance by measuring the eardrum temperature, rectal temperature, armpit temperature, etc. with other sensors. sensor When using the armpit temperature as a reference temperature for determining the temperature T, a commercially available thermometer is attached to the armpit of the living body 100 for a few minutes, and the temperature T skin and T t The temperature at which the temperature becomes approximately the same as the reference temperature can be used.

[0033] In this embodiment, when the sensor unit 1 is cylindrical with a diameter D of 30 mm and a thickness t of 4 mm, the thermal conductor 10 has a thermal conductivity of 1 W / m 2 The thermal conductor 10 may be made of the above-mentioned materials. The thermal conductor 10 may be made in a truncated cone shape, the diameter d1 of the through hole 16 may be about 8 mm, the diameter d2 of the outer edge of the thermal conductor 10 may be about 16 mm to 30 mm, the thickness t2 of the thermal conductor 10 may be 1 mm or more, and the coating materials 11 and 14 may be made of a material having a thermal conductivity of 0.2 W / m2 The thickness of the housing 15 is about 0.5 mm, and the distance between the temperature sensors 12 and 13 is about 2 mm. Then, the deep body temperature T body In addition, when the diameter D of the sensor part 1 is set to 26 mm or less, the thermal conductivity of the thermal conductor 10 is set to 10 W / m 2 It needs to be more than that.

[0034] FIG. 7 shows a deep body temperature T estimated by attaching the temperature measuring device 102 of this embodiment to the forehead of a living body 100. body For comparison, the deep temperature (tympanic membrane temperature) T measured by a tympanic membrane thermometer e 7, 70, 71, and 72 show the results for different living bodies 100. FIG. 8 shows the deep body temperature T body and tympanic membrane temperature T e 7 and 8 show the time change of the tympanic membrane temperature T e It can be seen that the present embodiment provides an estimation result close to the above.

[0035] [Second Example] Next, a second embodiment of the present invention will be described. Fig. 9 is a diagram showing the configuration of a temperature measuring device according to the second embodiment of the present invention, and Fig. 10 is an external view of the temperature measuring device. A temperature measuring device 102a of this embodiment is composed of a sensor unit 1a and an electronic circuit unit 2a.

[0036] In this embodiment, instead of the temperature sensor 13 of the sensor unit 1 of the first embodiment, a heat flux sensor 17 is provided on the surface of the covering material 11 of the sensor unit 1a facing the living body 100. The temperature sensor 12 and the heat flux sensor 17 constitute a detection unit 18a that measures the magnitude of the heat flow. The other configuration of the sensor unit 1a is the same as that of the sensor unit 1. The electronic circuit unit 2 a includes a storage unit 20 , a calculation unit 21 a , a communication unit 22 , a control unit 23 , a power supply unit 24 , and a housing 25 .

[0037] 11 is a flow chart for explaining the operation of the temperature measuring device 102a of this embodiment. As in the first embodiment, the temperature sensor 12 detects the temperature T skin is measured (FIG. 11, Step S100a).

[0038] The heat flux sensor 17 detects the heat flux H signal The measurement data of the temperature sensor 12 and the heat flux sensor 17 are temporarily stored in the storage unit 20.

[0039] As in the first embodiment, the storage unit 20 stores a proportionality coefficient R sensor The calculation unit 21a stores the temperature T skin and heat flux H signal and the proportionality coefficient R sensor Based on this, the deep body temperature T of the living body 100 body is calculated, for example, by equation (1) (FIG. 11, step S101a). The communication unit 22 detects the deep body temperature T body The data is transmitted to the external terminal (FIG. 11, step S102).

[0040] The temperature measuring device 102a performs the above steps S100a, S104, S101a, and S102 at regular time intervals until, for example, a command to end the measurement is received from the user (YES in step S103 in FIG. 11). Thus, in this embodiment, the same effects as in the first embodiment can be obtained.

[0041] [Third Example] Next, a third embodiment of the present invention will be described. Fig. 12 is a diagram showing the configuration of a temperature measuring device according to the third embodiment of the present invention, and Fig. 13 is an external view of the temperature measuring device. A temperature measuring device 102b of this embodiment has a sensor unit 1 and an electronic circuit unit 2 housed in the same housing 15b. In this embodiment, the electronic circuit unit 2 is provided inside a covering material 14 that covers the thermal conductor 10 of the sensor unit 1.

[0042] Note that the sensor unit 1a of the second embodiment may be provided instead of the sensor unit 1, and the electronic circuit unit 2a of the second embodiment may be provided instead of the electronic circuit unit 2. The operation of the temperature measuring device 102b is the same as that of the first or second embodiment.

[0043] [Fourth Example] Next, a fourth embodiment of the present invention will be described. Fig. 14 is a diagram showing the configuration of a temperature measuring device according to the fourth embodiment of the present invention, and Fig. 15 is an external view of the temperature measuring device. A temperature measuring device 102c of this embodiment has an electronic circuit section 2 provided on a sensor section 1, and the sensor section 1 and the electronic circuit section 2 are stored in the same housing 15c. In this embodiment, the electronic circuit section 2 is provided inside a covering material 14 that covers the thermal conductor 10 of the sensor section 1.

[0044] According to this embodiment, the installation area of ​​the temperature measuring device 102c can be reduced. The sensor unit 1a of the second embodiment may be provided instead of the sensor unit 1, and the electronic circuit unit 2a of the second embodiment may be provided instead of the electronic circuit unit 2. The operation of the temperature measuring device 102c is the same as that of the first or second embodiment.

[0045] The storage unit 20, the calculation units 21, 21a, the communication unit 22, and the control unit 23 described in the first to fourth embodiments can be realized by a computer equipped with a CPU (Central Processing Unit), a storage device, and an interface, and a program that controls these hardware resources. An example of the configuration of this computer is shown in FIG.

[0046] The computer includes a CPU 200, a storage device 201, and an interface device (I / F) 202. Hardware such as temperature sensors 12 and 13, heat flux sensor 17, and communication unit 22 are connected to the I / F 202. In such a computer, a program for implementing the temperature measurement method of the present invention is stored in the storage device 201. The CPU 200 executes the processes described in the first to fourth embodiments in accordance with the program stored in the storage device 201. [Industrial Applicability]

[0047] The present invention can be applied to a technique for non-invasively measuring the internal temperature of a living body. [Explanation of symbols]

[0048] 1,1a...sensor section, 2,2a...electronic circuit section, 10...thermal conductor, 11,14...coating material, 12,13...temperature sensor, 15,15b,15c,25...housing, 17...heat flux sensor, 18,18a...detection section, 20...memory section, 21,21a...calculation section, 22...communication section, 23...control section, 24...power supply section, 102,102a-102c...temperature measuring device.

Claims

1. A sensor unit configured to measure the magnitude of heat flow transmitted from a living body; and an electronic circuit unit configured to calculate an internal temperature of the living body based on the magnitude of the heat flow measured by the sensor unit, The sensor unit includes: A hollow heat conductor arranged so that a peripheral portion thereof comes into contact with the living body; a first covering material disposed to fill a space between the living body and the thermal conductor; A detector provided in the first covering material to measure a magnitude of a heat flow transmitted from the living body; and a second covering material disposed to cover the thermal conductor.

2. 2. The temperature measuring device according to claim 1, A temperature measuring device, characterized in that the electronic circuit unit is provided inside the second covering material next to the sensor unit.

3. 2. The temperature measuring device according to claim 1, A temperature measuring device, characterized in that the electronic circuit portion is provided inside the second covering material on the sensor portion.

4. The temperature measuring device according to any one of claims 1 to 3, A temperature measuring device further comprising a housing provided to cover the second outer covering material.

5. The temperature measuring device according to any one of claims 1 to 4, The detection unit is a first temperature sensor provided on a surface of the first covering material facing the living body and configured to measure a temperature of a surface of the living body; a second temperature sensor configured to measure a temperature inside the first coating immediately above the first temperature sensor; The temperature measuring device according to claim 1, wherein the electronic circuit unit calculates an internal temperature of the living body based on the measurement results of the first and second temperature sensors.

6. The temperature measuring device according to any one of claims 1 to 4, The detection unit is a temperature sensor provided on a surface of the first covering material facing the living body and configured to measure a temperature of a surface of the living body; a heat flux sensor provided on a surface of the first covering material facing the living body and configured to measure a heat flux flowing from the living body into the sensor unit; The temperature measuring device is characterized in that the electronic circuit unit calculates the internal temperature of the living body based on the measurement results of the temperature sensor and the heat flux sensor.

Images