Deep body temperature measuring probe and deep thermometer

Abstract

A probe (1) for measuring deep body temperature is used for measuring the deep body temperature of a subject (9), and comprises: a plate-shaped substrate (10); a pair of first region temperature sensors (21, 22) mounted in a first region (11) of the substrate so as to face each other with the substrate (10) therebetween; and a pair of second region temperature sensors (23, 24) mounted in the second region (12) of the substrate so as to face each other with the substrate (10) therebetween. Wherein, on the substrate 10, a through hole 15 penetrating between the front surface 10a and the back surface 10b of the substrate 10 is formed directly below the first region temperature sensors 21, 22, and the pair of first region temperature sensors 21, 22 are connected through the through hole 15. According to this probe (1) for measuring deep body temperature, even if the substrate constituting the probe is thinned, the deep body temperature of a subject can be measured with high accuracy.

Description

Technical Field

[0001] The present invention relates to a probe for measuring deep body temperature and a deep thermometer, and mainly to a probe for measuring deep body temperature (core body temperature) of a human body and a deep thermometer. Background Art

[0002] For a long time, people have been studying the dual heat flow method for measuring the deep body temperature of the human body by non-invasive methods. The dual heat flow method is a method for calculating the deep body temperature TB by measuring the heat flow passing through two different insulating materials and solving the simultaneous equations related to the heat flow without using the thermal resistance value of the biological skin as an unknown variable (for example, refer to non-patent document 1).

[0003] Non-patent document 1 and patent document 1 disclose a probe for measuring deep body temperature TB using a dual heat flow method (hereinafter sometimes referred to as a "probe"). In order to construct a probe for the total heat flow method, it is important to set a difference between the thermal resistance values ​​of the two heat flow paths (the thermal resistance value of the first heat flow path and the thermal resistance value of the second heat flow path), and these documents also disclose probes that have been improved for this purpose.

[0004] The deep body temperature measurement probe described in Patent Document 1 is configured to generate a difference in thermal resistivity by making the occupancy rate and / or variance of the conductive pattern in the first region of the substrate different from the occupancy rate and / or variance of the conductive pattern in the second region. Figure 1 In the example, a conductive pattern is arranged between the layers of the substrate in the first heat flow path to reduce the overall thermal resistance R. On the other hand, no such conductive pattern is arranged between the layers in the second heat flow path, and the second heat flow path is constituted by the substrate material itself. Overall, there is a difference in the thermal resistance values ​​of the heat flow paths on both sides.

[0005] [Non-patent document 1] Yanai Kazunari, “Development of a non-invasive deep thermometer and verification in basic experiments,” Master’s thesis, Graduate School of Information Science, Nara Institute of Science and Technology, NAIST Digital Library, 2014.

[0006] [Patent Document 1] International Publication No. 2019 / 167707

[0007] It is estimated that there are many cases of high temperatures in the summer recently, and from the perspective of preventing heat stroke, measures to install deep body temperature measurement probes on the body to monitor the deep body temperature TB (especially the deep body temperature of the human body) will increase in the future. As an expected attribute of wearable detectors, "thinness" is also important in order to reduce the resistance during installation and increase the installation rate.

[0008] However, if the thickness of the substrate constituting the probe for measuring deep body temperature is made thinner, the dimension in the thickness direction will become smaller, and therefore the thermal resistance value in the thickness direction will develop in the direction of decreasing. At this time, if the technology of the probe for measuring deep body temperature described in Patent Document 1 is used, even if a conductive pattern is added between layers in order to reduce the thermal resistance value of the first area, the thermal resistance value of the second area will also become smaller due to the thinning of the substrate, so it is difficult to produce a difference in thermal resistance value between the two areas. Therefore, even if a thin wearable probe for measuring deep body temperature is constructed using the technology described in Patent Document 1, it is difficult to maintain a high accuracy of the measurement estimation (hereinafter referred to as "measurement") of the deep body temperature.

[0009] In addition, in the deep body temperature measurement probe described in Patent Document 1, the smaller the size of the substrate is set, the more difficult it is to embed more conductive patterns inside, which lacks feasibility and practicality.

[0010] Therefore, the present invention has been completed in view of the above situation, and its purpose is to provide a deep thermometer measuring probe that can measure the deep body temperature of a subject with high accuracy even if the substrate constituting the probe is thinned. In addition, the present invention also aims to provide a deep thermometer having such a deep thermometer measuring probe. Summary of the invention

[0011] According to one form of the present invention, there is provided a probe for measuring deep body temperature, which is used when measuring the deep body temperature of a subject, and is characterized in that it includes: a substrate; a pair of first-area temperature sensors, which are a pair of temperature sensors installed opposite to each other in a first area of ​​the substrate with the substrate interposed therebetween; and a pair of second-area temperature sensors, which are a pair of temperature sensors installed opposite to each other in a second area of ​​the substrate with the substrate interposed therebetween, wherein a through hole is formed on the substrate directly below the first-area temperature sensor and passes through the surface and back of the substrate, and the pair of first-area temperature sensors are connected via the through hole.

[0012] According to another aspect of the present invention, there is provided a deep body temperature measuring probe similarly used for measuring the deep body temperature of a subject.

[0013] The deep body temperature measurement probe includes: a plate-shaped substrate; a first heat flow measurement system, which has a pair of body temperature sensors installed opposite to each other in a first area of ​​the substrate with the substrate separated therefrom, namely, a "pair of first-area body temperature sensors", and a first heat flow path formed in the substrate in the first area, which is used to measure the first heat flow flowing out of the subject; and a second heat flow measurement system, which has a pair of body temperature sensors installed opposite to each other in a second area of ​​the substrate with the substrate separated therefrom, namely, a "pair of second-area body temperature sensors", and a second heat flow path formed in the substrate in the second area, which is used to measure the second heat flow flowing out of the subject, wherein, on the substrate, a through hole is formed directly below the first-area body temperature sensor, which passes through the surface and the back of the substrate, and the first heat flow path is composed of an air layer arranged inside the through hole.

[0014] According to another aspect of the present invention, there is provided a deep body thermometer comprising: the deep body temperature measuring probe described above; and a deep body temperature estimating unit for estimating the deep body temperature using the body temperatures measured by a pair of first area temperature sensors and a pair of second area temperature sensors of the deep body temperature measuring probe.

[0015] Effects of the Invention

[0016] According to the present invention, a deep thermometer measuring probe can be provided which can measure the deep body temperature of a subject with high accuracy even if the substrate constituting the probe is thinned. In addition, a deep thermometer including such a deep thermometer measuring probe can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a diagram for explaining the deep body temperature measurement probe 1 according to the first embodiment.

[0018] Figure 2 This is a diagram showing the components of the deep body temperature measurement probe 1 according to the first embodiment.

[0019] Figure 3 This is a block diagram showing an example of the hardware structure of the deep thermometer 500 involved in the first embodiment.

[0020] Figure 4 1 is a thermal equivalent circuit diagram showing the deep body temperature measurement probe 1 according to the first embodiment.

[0021] Figure 5 It is a cross-sectional view of an experimental system showing the deep body temperature measurement probe 1 according to the first embodiment.

[0022] Figure 6 1 is a cross-sectional view showing a deep body temperature measurement probe 2 according to the second embodiment.

[0023] Figure 7 1 is a cross-sectional view showing a deep body temperature measurement probe 3 according to a third embodiment.

[0024] Figure 8 This is a diagram for explaining the deep body temperature measurement probe 4 according to the fourth embodiment.

[0025] Fig. 9 1 is a cross-sectional view showing a deep body temperature measurement probe 5 according to Modification 1.

[0026] Fig.10 It is a cross-sectional view of the main parts showing the deep body temperature measurement probes 6 and 7 of Modification 2 and Modification 3.

[0027] Fig.11 It is a diagram for explaining the deep body temperature measurement probes 4 ′, 4 ″ according to the fourth modification. DETAILED DESCRIPTION

[0028] Hereinafter, the probe for measuring deep body temperature and the deep body thermometer of the present invention will be described with reference to the accompanying drawings. In addition, regarding the common symbols of each figure, the contents already described for the symbols can also be cited in the description of other figures, so the description of other figures is omitted.

[0029] [Implementation method 1]

[0030] 1. Structure of the Deep Body Temperature Measurement Probe 1 According to Embodiment 1

[0031] Figure 1 This is a diagram for explaining the deep body temperature measurement probe 1 according to the first embodiment. Figure 1 (a) Yes Figure 1 (b) is a cross-sectional view of the deep body temperature measurement probe 1 at the BB section. Figure 1 (b) is along Figure 1 (a) is a plan view of the deep body temperature measurement probe 1 when viewed from an arrow A. Figure 2 This is a diagram showing components of the deep body temperature measurement probe 1 according to the first embodiment.

[0032] (1) Overview of deep body temperature measurement probe 1

[0033] like Figure 1 As shown, the deep body temperature measurement probe 1 is a probe used when measuring the body temperature of the deep part 9c of the subject 9, which is the deep part of the subject 9. The body temperature (deep body temperature TB) of the deep part 9c of the subject is measured by making the back side directly or indirectly contact the surface 9a of the subject. In the figure, the symbol RS represents the thermal resistance value of the middle part 9b of the subject that cannot be directly measured.

[0034] Typical examples of the subject 9 include living organisms such as humans and animals, but the present embodiment will be described assuming humans.

[0035] The deep body temperature measurement probe 1 includes a substrate 10 and body temperature sensors 21, 22, 23, and 24. In the present specification, the body temperature sensor may be simply referred to as a "sensor".

[0036] (2)Substrate 10

[0037] Figure 2 (a) is a plan view showing the substrate 10, and shows a state when observing the surface of the bare substrate on which the body temperature sensors 21, 22, 23, 24, 25 are not mounted.

[0038] like Figure 2 As shown in (a), the substrate 10 is a printed substrate on which a wiring pattern 13 is formed. For example, an epoxy glass substrate can be used as the substrate 10. The substrate 10 of this embodiment is a so-called double-sided substrate having wiring patterns 13 on both sides of the surface 10a and the back surface 10b. The wiring pattern 13 (wiring pattern in a broad sense) includes terminals 13c, wiring patterns 13a in a narrow sense connecting the terminals 13c, and pads 13b in a narrow sense formed in the shape of pads. In addition, the description of the connection in the middle of the wiring pattern 13a in a narrow sense is omitted in the figure.

[0039] The substrate 10 has a surface 10a and a back surface 10b, and has a plate-like shape. In addition, the definition of the surface 10a and the back surface 10b here is for convenience, and the surface facing the outside world (the atmosphere 8 side) is set as the surface 10a, and the surface of the side that contacts the subject 9 is set as the back surface 10b.

[0040] The substrate 10 has a function as a base for mounting the body temperature sensors 21, 22, 23, and 24, and a part (or the whole) thereof constitutes a heat flow path (heat flow path) for heat flowing from the back surface 10b side to the front surface 10a side (see also Figure 1 ).

[0041] (3) Body temperature sensors 21, 22, 23, 24

[0042] Since the body temperature sensors 21, 22, 23, and 24 measure the body temperature of the contact part (node) and output an output signal corresponding to the measured body temperature, they can be composed of discrete devices such as thermocouples, platinum resistors, and thermistors, or devices that are integrated circuits (ICs) and output digital output signals.

[0043] The body temperature sensors 21, 22, 23, and 24 of the present embodiment are implemented as IC sensors, and may be implemented by a so-called SON package (Small Outline Non-leaded package), for example, as shown in the figure.

[0044] Figure 2(b) is a bottom view showing the bottom surface of the package when the body temperature sensor 21, 22, 23, 24, 25 is implemented by a SON package. The body temperature sensor 21, 22, 23, 24, 25 has a semiconductor chip (not shown) having the function of sensing body temperature and converting it into an electrical signal inside, and the external connection terminal 28 electrically connected to the semiconductor chip is exposed to the bottom surface. In addition, the body temperature sensor 21, 22, 23, 24, 25 also has a thermal pad 29 on the bottom surface for achieving good thermal coupling between the contact portion to be measured (specifically, the node of the heat flow path) and the internal semiconductor chip.

[0045] return Figure 1 , continue to explain the substrate installation of the body temperature sensor.

[0046] The body temperature sensors 21 and 22 are mounted in the first area 11 of the substrate 10 so as to face each other across the substrate 10. The body temperature sensor 21 is mounted on the back surface 10b of the substrate 10, and the body temperature sensor 22 is mounted on the front surface 10a of the substrate 10. Similarly, the body temperature sensors 23 and 24 are mounted in the second area 12 of the substrate 10 so as to face each other across the substrate 10. The body temperature sensor 23 is mounted on the back surface 10b of the substrate 10, and the body temperature sensor 24 is mounted on the front surface 10a of the substrate 10.

[0047] In the figure, reference numeral 60 indicates an external connector for connecting to the outside. Reference numeral 25 is a temperature sensor for measuring the temperature of the outside air. As described later, when the thermal resistance ratio K is experimentally determined, the thermal resistance ratio K is corrected using the outside air temperature T5 measured by the temperature sensor 25. In addition, the temperature sensor 25 is arranged adjacent to the areas constituting the first area 11 and the second area 12. The outside air temperature can be measured using one module, and overall, the deep thermometer 500 can be realized in a small, lightweight, and inexpensive manner.

[0048] In this specification, the pair of body temperature sensors 21 and 22 may be referred to as “a pair of first-area body temperature sensors 21 and 22 ”, and the pair of body temperature sensors 23 and 24 may be referred to as “a pair of second-area body temperature sensors 23 and 24 ”, respectively.

[0049] The so-called "first region 11" and "second region 12" are regions where a "first heat flow path 115" and a "second heat flow path 125" are provided to have a difference in thermal resistance R1 and R2, respectively, when performing deep body temperature measurement based on the dual heat flow method (see Figure 1 (b) Figure 2 wait).

[0050] The external connection terminals 28 of the temperature sensors 21, 22, 23, and 24 are connected to the terminals 13c of the substrate 10 via the “solder 51”, thereby electrically connecting both parties, and each sensor is fixed to the substrate 10.

[0051] The thermal pads 29 of the temperature sensors 23 and 24 are connected to the entire overlapping area of ​​the substrate 10 via the "solder 51", thereby achieving good thermal coupling with the pad 13b of the substrate 10 (the node serving as the connection point of the second heat flow path 125), and the distance between the thermal pads 29 and the pads 13b is fixed by the "solder 51", which can prevent dynamic distance changes (assuming that there is no solder 51 but only a gap).

[0052] During welding, the thickness of the "solder 51" is controlled within a predetermined range of deviation, so that the distance between the thermal pad 29 and the pad 13b is substantially constant. Thus, the distance between the pair of second area temperature sensors 23 and 24 can be kept substantially constant, and the thermal resistance value R2 of the second heat flow path 125 can be managed to be substantially constant with good reproducibility even in mass production.

[0053] Next, focusing on the second region 12 of the substrate 10, the second heat flow path 125 is formed by the substrate 10 itself and the "solder 51" inserted between the thermal pad 29 and the pad 13b. Since the second heat flow path 125 is formed while effectively utilizing the substrate 10 itself, the probe can be formed with a simple structure without performing special processing or increasing the number of parts, and is an economical probe.

[0054] The second heat flow 120a flows from the back side to the front side of the deep body temperature measurement probe 1 through the second heat flow path 125 (see Figure 1 Symbol 120a) schematically indicated by a thick arrow in (a).

[0055] (4) Structure of the First Heat Flow Path 115

[0056] On the other hand, focusing on the first region 11 of the substrate 10, a through hole 15 is formed on the substrate 10, which passes through the front surface 10a and the back surface 10b of the substrate 10, just below the body temperature sensors 21 and 22 (first region body temperature sensors 21 and 22). The pair of first region body temperature sensors 21 and 22 are connected by the through hole 15. The "connection" here includes both spatial connection and connection from the perspective of thermal circuit.

[0057] In addition, in the deep body temperature measurement probe 1 according to Embodiment 1, an air layer 30 is disposed inside the through hole 15. Reference numeral 15a denotes an inner wall of the through hole.

[0058] The first heat flow path 115 is formed by the gap (the air layer 30 in the first embodiment) between the through holes 15. In other words, the thermal resistor forming the first heat flow path 115 is realized by the air layer 30 disposed inside the through holes 15 formed in the substrate 10.

[0059] Through the first heat flow path 115, the first heat flow 110a flows from the back side to the front side of the deep body temperature measurement probe 1 (see Figure 1 Symbol 110a) is schematically indicated by a thick arrow in (a).

[0060] In addition, the first area body temperature sensors 21 and 22 are made of semiconductor ICs, and preferably, when viewed from above, the through holes 15 overlap with 50% or more of the area of ​​the IC thermal pad 29 (or the back surface of the bare chip in the later-described modification 3) (see Figure 1 More preferably, the through holes 15 overlap the entire area of ​​the thermal pad 29 .

[0061] (5) First heat flow measurement system 110 and second heat flow measurement system 120

[0062] The first heat flow path 115 formed in the substrate of the first region 11 and the pair of first region body temperature sensors 21, 22 constitute the "first heat flow measurement system 110". Similarly, the second heat flow path 125 formed in the substrate of the second region 12 and the pair of second region body temperature sensors 23, 24 constitute the "second heat flow measurement system 120".

[0063] The deep body temperature measurement probe 1 according to the first embodiment can also be said to have the following structure.

[0064] That is, it includes: a pair of first area temperature sensors 21 and 22 installed opposite to each other in the first area 11 of the substrate 10 with the substrate 10 interposed therebetween, and a first heat flow path 115 formed in the substrate in the first area 11, and a "first heat flow measurement system" for measuring a first heat flow 110a flowing out from the subject 9. Also, it includes: a pair of second area temperature sensors 23 and 24 installed opposite to each other in the second area 12 of the substrate 10 with the substrate 10 interposed therebetween, and a second heat flow path 125 formed in the substrate in the second area 12, and a "second heat flow measurement system 120" for measuring a second heat flow 120a flowing out from the subject 9. Also, on the substrate 10, a through hole 15 penetrating between the front and back surfaces of the substrate 10 is formed directly below the first area temperature sensors 21 and 22, and the first heat flow path 115 is formed of an air layer 30 disposed inside the through hole 15.

[0065] 2. Structure of Deep Thermometer 500 According to Embodiment 1

[0066] Figure 3This is a block diagram showing an example of the hardware configuration of the deep thermometer 500 according to Embodiment 1. Reference numeral 200 denotes a temperature measurement unit.

[0067] The structure of the deep body thermometer 500 involved in embodiment 1 can include the deep body temperature measurement probe 1 involved in the above-mentioned embodiment 1; and a deep body temperature estimation unit 210 that estimates the deep body temperature TB using the body temperatures measured by a pair of first area temperature sensors 21, 22 and a pair of second area temperature sensors 23, 24 of the deep body temperature measurement probe 1.

[0068] The deep body temperature estimating unit 210 calculates the deep body temperature TB as an estimated value by the double heat flow method “for example, by calculation of the equation (10) described later”.

[0069] The deep body temperature estimation unit 210 may be composed of either a dedicated circuit or a general-purpose circuit. Figure 3 The information processing device (without symbol) shown is implemented.

[0070] The information processing device constituting the deep body temperature estimating unit 210 includes a processor 211, a memory 212, an input / output interface 214, and a communication interface 215. These are connected to a bus BS.

[0071] The processor 211 operates based on the program stored in the storage unit (memory 212 and storage device (not shown)) to control each component. The storage unit (unsigned) also includes a non-volatile storage device (ROM, etc.), which stores a boot program executed by the processor 211 when the information processing device is started, a program that depends on the hardware of the information processing device, etc. The memory not shown is composed of auxiliary storage devices such as SDD (Solid State Drive) and HDD (Hard Disk Drive). The memory 212 appropriately stores data required when the processor 211 performs various control processes.

[0072] The processor 211 applies the body temperatures T1 to T4 and the like to the equation (10) described later, and calculates the deep body temperature TB as an estimated value. In this case, the deep body temperature estimating unit 210 may also be referred to as a function of a processor that calculates and estimates the deep body temperature TB.

[0073] The input / output interface 214 performs input / output from the input / output devices (especially the body temperature sensors 21, 22, 23, 24, 25). The communication interface 215 receives data from other electronic devices via a network, etc., transmits it to the processor 211, and transmits data generated by the processor 211 to other electronic devices via a network, etc.

[0074] 3. About Experimental

[0075] When estimating the deep body temperature TB, the value of the thermal resistance ratio K of the first heat flow measurement system 110 and the second heat flow measurement system 120 needs to be identified and prepared in the formula (10) described later. If the materials and physical properties constituting the first heat flow path 115 and the second heat flow path 125 are known, the thermal resistance ratio K can also be theoretically calculated. However, the inventors have experimentally calculated the thermal resistance ratio K that conforms to the actual situation in advance in another experimental system, and on this basis, they have also developed a method for applying the thermal resistance ratio K to the formula (10), which is described in detail below.

[0076] (1) Thermal equivalent circuit of deep body temperature measurement probe 1

[0077] Figure 4 1 is a thermal equivalent circuit diagram of the deep body temperature measurement probe 1 according to the first embodiment.

[0078] Figure 4 Ia shown is the heat flow (value) flowing through the first heat flow path 115, and Ib is the heat flow (value) flowing through the second heat flow path 125. Ic is the heat flow (value) flowing through the thermal resistance Rs (thermal resistance value) between the deep part 9c of the subject and the surface 9a (skin) of the subject in the first heat flow measurement system 110, and Id is the heat flow (value) flowing through the thermal resistance Rs (thermal resistance value) between the deep part 9c of the subject and the surface 9a (skin) of the subject in the second heat flow measurement system 120.

[0079] according to Figure 4 In the thermal equivalent circuit shown, for the first heat flow measurement system 110 , the following equation holds true.

[0080] Ia=(T1-T3) / R1···(1)

[0081] Ic=(TB-T1) / RS···(2)

[0082] Ia=Ic=(T1-T3) / R1=(TB-T1) / RS···(3)

[0083] According to formula (3)

[0084] TB=T1+(T1-T3)×(Rs / R1)···(4)

[0085] Similarly, for the second heat flow measurement system 120 , the following equation holds true.

[0086] Ib=(T2-T4) / R2···(5)

[0087] Id=(TB-T2) / RS···(6)

[0088] Ib=Id=(T2-T4) / R2=(TB-T2) / RS···(7)

[0089] According to formula (7)

[0090] TB=T2+(T2-T4)×(Rs / R2)···(8)

[0091] Here, there is a method of obtaining the deep body temperature TB by removing Rs using equations (4) and (8). However, the inventors have found through experiments that it is difficult to obtain an accurate deep body temperature.

[0092] Therefore, the inventors decided to use other methods to obtain the deep body temperature TB.

[0093] First, according to Figure 4 The thermal equivalent circuit of the first heat flow measurement system 110 and the second heat flow measurement system 120 is defined as follows.

[0094] K=[(TB-T2)(T1-T3)] / [(TB-T1)(T2-T4)](9)

[0095] Therefore, the formula (9) can be transformed into the following formula for calculating the deep body temperature TB.

[0096] TB=T1+(T1-T2)(T1-T3) / [K(T2-T4)-(T1-T3)](10)

[0097] The inventors conducted preliminary experiments based on this idea and determined the thermal resistance ratio K using the relationship of formula (9). Then, using the relationship of formula (10), the deep body temperature TB was calculated (estimated) based on the thermal resistance ratio K determined in the preliminary experiment and the body temperatures (T1, T2, T3, T4) measured by the body temperature sensors (15, 16, 17, 18).

[0098] After conducting experimental verification, it was confirmed that the correct deep body temperature can be obtained.

[0099] That is, for the thermal resistance ratio K of the first heat flow path 115 between the pair of first area temperature sensors 21 and 22 and the second heat flow path 125 between the pair of second area temperature sensors 23 and 24 in the deep body temperature estimating unit 210 according to the first embodiment,

[0100] It is confirmed that the thermal resistance ratio K predetermined by the relationship K=[(TB-T2)(T1-T3)] / [(TB-T1)(T2-T4)] and the body temperatures T1, T2, T3 and T4 measured by the detection of the subject 9 are used.

[0101] The deep body temperature TB may be estimated from the relationship of TB=T1+(T1-T2)(T1-T3) / [K(T2-T4)-(T1-T3)].

[0102] Among them, the deep body temperature is set to TB, and the body temperatures measured by sensor 21 of a pair of first area temperature sensors arranged on the side of the subject 9, sensor 22 of a pair of second area temperature sensors arranged on the side of the subject 9, sensor 23 of a pair of first area temperature sensors arranged on the opposite side of the subject 9, and sensor 24 of a pair of second area temperature sensors arranged on the opposite side of the subject 9 are set to T1, T2, T3 and T4 respectively.

[0103] In addition, formula (2.6) of non-patent document 1 is considered to correspond to formula (10) of this specification. However, after the inventors tested formula (2.6) of non-patent document 1, it should be noted that formula (2.6) of non-patent document 1 may contain errors.

[0104] (2) Composition of the experimental system

[0105] Figure 5 1 is a cross-sectional view schematically showing an “experimental system” for experimentally obtaining and determining the thermal resistance ratio K of the deep body temperature measurement probe 1.

[0106] like Figure 5 As shown, a water bath 130 with a large heat capacity is used instead of the deep part 9c of the specimen, and it is arranged in a constant temperature and humidity chamber (not shown). The body temperature (ambient body temperature) in the constant temperature and humidity chamber is set to a specified body temperature between 10°C and 30°C. The water temperature (deep body temperature TB) is set to be approximately constant (about 37°C). In addition, symbol 109 represents a substitute specimen, and the surface 109a of the substitute specimen is composed of a substitute skin made of a natural rubber sheet that imitates the skin of a biological body. Symbol 109b is a part corresponding to the middle part of the substitute specimen, and symbol 109c is a part corresponding to the deep part of the substitute specimen. Symbol 131a is a support rod that supports the body temperature sensor 131 (thermistor, etc.).

[0107] The deep body temperature measurement probe 1 is placed on the aluminum barrel 133 so that the aluminum barrel 133 floats in the water in the water bath 130 .

[0108] By using such an experimental system, by measuring the body temperature with the body temperature sensor 131, (i) the actual deep water temperature (deep body temperature TBr) in the water bath 130 can be obtained. Furthermore, the body temperature sensed by the body temperature sensors 21 to 24 of the deep body temperature measurement probe 1 is measured by the body temperature measurement unit 200 and output to the deep body temperature estimation unit 210, and the deep body temperature estimation unit 210 performs calculations based on the body temperature, thereby also obtaining (ii) the estimated deep water temperature (deep body temperature TBp).

[0109] (3) Determination of thermal resistance ratio K

[0110] Using equation (9), the thermal resistance ratio K can be determined by conducting an experiment (preliminary experiment) as follows.

[0111] (A) A preliminary experiment is conducted to measure the actual deep water temperature (deep body temperature TBr), and the body temperatures T1 to T4 are measured using the body temperature sensors 21 to 24. The deep body temperature measurement probe 1 (in Figure 5 The thermal resistance ratio K in the experimental system shown in the figure (in the state of thermal equilibrium) is calculated using the relationship in formula (9).

[0112] (B) The average value of the thermal resistance ratio K obtained by multiple experiments is calculated.

[0113] (C) The measured value of the water temperature (deep body temperature TBr) is compared with the estimated deep body temperature TBp (water temperature) calculated by applying the average value of the thermal resistance ratio K and the body temperatures T1 to T4 to the relationship of formula (10), and it is checked whether the difference (error) between the two has become smaller. If the error is large, the above operations (A) to (C) are repeated again to determine the thermal resistance ratio K with a smaller error.

[0114] (4) Estimation of deep body temperature TB

[0115] The value of the thermal resistance ratio K determined as above is stored in the memory 212 (refer to Figure 3 The body temperature is measured using the body temperature sensors 21 to 24 and the body temperature measurement unit 200, and the deep body temperature estimation unit 210 performs the operation of equation (10), thereby being able to calculate (estimate) the deep body temperature TB.

[0116] (5) Reference to Prior Application

[0117] In addition, the contents of the prior application (Japanese Patent Application No. 2022-53593) which describes the contents of the invention by the inventors of the present application (for example, Figure 4 , paragraphs

[0038] to

[0046] , etc.) are directly introduced into this specification and cited as a method for experimentally determining the thermal resistance ratio K of the present invention in advance. Detailed description on the determination of the experimental thermal resistance ratio K is omitted below.

[0118] 4. Effects of the Deep Body Thermometer Probe 1 and Deep Body Thermometer 500 According to Embodiment 1

[0119] (1) On the substrate of the deep body temperature measurement probe 1 involved in Embodiment 1, a through hole 15 is formed directly below the first area body temperature sensors 21 and 22, penetrating between the front and back surfaces of the substrate 10, and the pair of first area body temperature sensors 21 and 22 are connected via the through hole 15.

[0120] That is, in the probe 1 for measuring deep body temperature, since a pair of first area body temperature sensors 21 and 22 are connected by a through hole 15 formed directly below the sensor, if, for example, the structure is only a hole and no special treatment is performed, there is only an air layer 30 in the through hole 15, which can significantly increase the thermal resistance value R1 between the pair of first area temperature sensors 21 and 22.

[0121] Therefore, even if the substrate 10 constituting the probe is thinned and the overall thermal resistance value of the substrate 10 in the thickness direction becomes smaller, it is easy to set the difference between the thermal resistance value R1 of the first heat flow path 115 (between a pair of first area temperature sensors 21 and 22) and the thermal resistance value R2 of the second heat flow path 125 (between a pair of second area temperature sensors 23 and 24).

[0122] Therefore, even if the substrate 10 constituting the probe is thinned, the body temperature of the deep portion 9 c of the subject (deep body temperature TB) can be measured with high accuracy.

[0123] (2) The thermal conductivity of air is 0.0241 [W / (mK)] (at 0 [°C]), while the thermal conductivity of a member constituting the substrate 10, such as polyimide (PI), is 0.28 to 0.34 [W / (mK)].

[0124] In the deep body temperature measurement probe 1 according to the first embodiment, an air layer 30 is arranged inside the through hole 15. Therefore, when the deep body temperature measurement probe 1 is viewed from the viewpoint of thermal resistance, the air layer 30 can have a relatively large thermal resistance value compared with the components constituting the substrate 10 and the like. Therefore, since the thermal resistance value R1 of the first heat flow path 115 constituted by the air layer 30 can be significantly increased, as a structure for setting the difference between the thermal resistance value R1 of the first heat flow path 115 and the thermal resistance value R2 of the second heat flow path 125, this can be achieved with a very simple structure.

[0125] (3) The deep body thermometer 500 according to Embodiment 1 includes: the deep body temperature measuring probe 1 according to Embodiment 1; and a deep body temperature estimating unit 210 for estimating the deep body temperature using the body temperatures measured by the pair of first area body temperature sensors 21, 22 and the pair of second area body temperature sensors 23, 24 of the deep body temperature measuring probe 1.

[0126] The deep thermometer 500 is a small and highly accurate deep thermometer because it includes the deep thermometer measurement probe 1 that can measure the body temperature (deep body temperature TB) of the deep part 9 c of the subject with high accuracy even on a thin substrate 10 .

[0127] (4) The deep thermometer 500 involved in embodiment 1 calculates the deep temperature TB by applying the thermal resistance ratio K predetermined using the relationship shown in the above formula (9) for calculating the thermal resistance ratio K, and the temperatures T1, T2, T3 and T4 measured by detecting the subject 9 to the relationship shown in the above formula (10).

[0128] In reality, considering that the heat flux in the diffusion mode is affected in addition to the linear heat flux, the thermal resistance ratio K theoretically obtained based on the known thermal conductivity of the material constituting each heat flow path may be different from the actual correct thermal resistance ratio K. Therefore, by predetermining the thermal resistance ratio K using the relationship represented by the above formula (9) in another experimental system, the deep body temperature TB can be estimated based on the thermal resistance ratio K with high accuracy close to that of the actual probe. Therefore, the deep body temperature can be measured with higher accuracy.

[0129] [Implementation method 2]

[0130] Figure 6 2 is a cross-sectional view of the deep body temperature measurement probe 2 according to Embodiment 2. The deep body temperature measurement probe 2 according to Embodiment 2 basically has the same structure as the deep body temperature measurement probe 1 according to Embodiment 1, but differs from the deep body temperature measurement probe 1 according to Embodiment 1 in the structure of the first heat flow path 115.

[0131] like Figure 6 As shown, in the deep body temperature measurement probe 2 according to the second embodiment, a heat insulating paper 31 is further arranged inside the through hole 15 .

[0132] The thermal insulation paper 31 is a paper having a thermal conductivity substantially equal to that of air. For example, a sheet into which porous particles composed of silica gel containing foamed air (so-called silica gel) are kneaded can be cited. When the thermal insulation paper 31 is placed in the air layer 30 provided in the through hole 15, the total thermal resistance value R1 of the internal space of the through hole 15 is almost the same as the thermal resistance value of air. The thermal insulation paper 31 can also be alternately folded into a wave shape, folded into a repeating shape of valleys, randomly curled, etc., to appropriately form the thermal insulation paper 31 in three dimensions and fill it in the internal space of the through hole 15.

[0133] By disposing the heat insulating paper 31 inside the through hole 15 constituting the first heat flow path 115, the heat insulating paper 31 can hinder the movement of air inside the through hole 15, and can suppress the convection inside the through hole 15. As a result, the heat transfer caused by "convection" in the first heat flow path 115 is suppressed, and the direct heat transfer caused by "conduction" through the air layer 30 and the heat insulating paper 31 is mainly performed. Therefore, it also becomes a more ideal state in the heat circuit, and the deep body temperature can be measured with higher accuracy.

[0134] The deep body temperature measurement probe 2 according to the second embodiment has a structure that is substantially the same as the deep body temperature measurement probe 1 according to the first embodiment except for the structure of the first heat flow path 115. Therefore, the deep body temperature measurement probe 2 also has corresponding effects among the effects of the deep body temperature measurement probe 1.

[0135] [Implementation method 3]

[0136] Figure 7 1 is a cross-sectional view of the deep body temperature measurement probe 3 according to Embodiment 3. The deep body temperature measurement probe 3 according to Embodiment 3 has basically the same structure as the deep body temperature measurement probe 1 according to Embodiment 1, but differs from the deep body temperature measurement probe 1 according to Embodiment 1 in the structure of the substrate 10 and the structural method of the first heat flow path 115.

[0137] like Figure 7 As shown, in the deep body temperature measurement probe 3 according to the third embodiment, the substrate 10 is formed of a glass substrate, and the interior of the through hole 15 is formed in a vacuum or near-vacuum state 32 .

[0138] By making the interior of the through hole 15 constituting the first heat flow path 115 a vacuum or near-vacuum state 32 , the thermal conductivity can be further reduced compared to the case of the air layer 30 , that is, the thermal resistance value R1 between the pair of first area temperature sensors 21 , 22 can be further increased.

[0139] The deep body temperature measurement probe 3 according to the third embodiment has a structure that is substantially the same as the deep body temperature measurement probe 1 according to the first embodiment except for the structure of the substrate 10 and the structure of the first heat flow path 115. Therefore, the deep body temperature measurement probe 2 also has the corresponding effects of the deep body temperature measurement probe 1.

[0140] [Implementation method 4]

[0141] Figure 8 This is a diagram for explaining the deep body temperature measurement probe 4 according to the fourth embodiment. Figure 8 (a) is shown Figure 8 (b) is a cross-sectional view of the deep body temperature measurement probe 4 at the cross section DD. Figure 8 (b) is along Figure 8 (a) is a plan view of the deep body temperature measurement probe 4 as viewed from an arrow C.

[0142] The deep body temperature measurement probe 4 involved in embodiment 4 has a structure basically the same as the deep body temperature measurement probe 1, 2, 3 of embodiments 1, 2, 3, but differs from the deep body temperature measurement probe 1, 2, 3 of embodiments 1, 2, 3 in suppressing thermal interference between the first heat flow path 115 and the second heat flow path 125.

[0143] like Figure 8 As shown, in the deep body temperature measurement probe 4 according to the fourth embodiment, an air layer 40 is arranged between the first region 11 and the second region 12 in the substrate 10. Figure 8 As shown, the air layer 40 may be composed of, for example, air that is formed through a through hole between the surface 10a and the back surface 10b of the substrate 10 and is disposed in the through hole. Figure 8 As shown, the through-hole may also be formed as an elongated hole that passes through most of the lateral region of the body temperature sensor.

[0144] Since the deep body temperature measurement probe 4 according to the fourth embodiment has such a structure, the air layer 40, also called a heat insulator, can block the heat conduction between the first region 11 provided with the first heat flow path 115 and the second region 12 provided with the second heat flow path 125. Thus, the thermal interference between the first heat flow path 115 and the second heat flow path 125 can be reduced, and the independence of the heat flow paths of both parties can be improved, so that the deep body temperature can be measured with higher accuracy.

[0145] The deep body temperature measurement probe 4 according to the fourth embodiment has a structure that is basically the same as the deep body temperature measurement probes 1, 2, and 3 according to the first, second, and third embodiments, except that the structure is configured to suppress the thermal interference between the first heat flow path 115 and the second heat flow path 125. Therefore, the deep body temperature measurement probe 4 also has the corresponding effects among the effects of the deep body temperature measurement probes 1, 2, and 3.

[0146] As mentioned above, although the present invention has been described based on the above-mentioned embodiment, the present invention is not limited to the above-mentioned embodiment. It can be implemented in various forms within the scope of the concept, and for example, the following modifications are also possible.

[0147] (1) In each embodiment, the second heat flow path 125 is formed by using the substrate 10 itself. However, the present invention is not limited thereto. Fig. 9 As shown, on the substrate 10, another through hole 17 is formed directly below the second area temperature sensors 23, 24, penetrating the surface 10a and the back surface 10b of the substrate 10, and metal 37 can be buried in the other through hole 17, and a pair of second area temperature sensors 23, 24 are connected via the metal 37 (variant example 1).

[0148] in addition, Fig. 91 is a cross-sectional view showing the deep body temperature measurement probe 5 according to Modification 1.

[0149] For example, copper can be used as the metal 37. The thermal conductivity of copper is 403 [W / (mK)] (but at 0 [°C]), which is significantly different from that of components constituting the substrate 10, etc. From the perspective of thermal resistance, the metal 37 can have a thermal resistance value that is slightly different from that of components constituting the substrate 10, etc. Therefore, the thermal resistance value R2 of the second heat flow path 125 constituted by the metal 37 can be significantly reduced, and the difference from the thermal resistance value R1 of the first heat flow path 115 can be easily ensured.

[0150] (2) In each embodiment, an example is shown in which the thermal pad 29 of the body temperature sensors 23 and 24 is connected to the pad 13b of the wiring pattern 13 by the solder 51. However, the present invention is not limited to this. For example, a structure (not shown) may be adopted in which the "solder 51" is not inserted between the thermal pad 29 and the pad 13b of the wiring pattern 13, and only a gap (air layer) is used without electrical connection. Even with this structure, thermal coupling between the pair of second area body temperature sensors 23 and 24 can be achieved.

[0151] (3) In each embodiment, the temperature sensors 21 to 24 are described as being implemented by using an IC packaged as a SON. However, the present invention is not limited thereto. Fig.10 As shown in (a), the body temperature sensors 21 to 24 can also be formed by WL-CSP (wafer level chip size package) ICs (variant 2). Fig.10 As shown in (b), the body temperature sensors 21 to 24 may be configured by directly mounting bare chips on the substrate 10 (variation 3). Although not shown, the body temperature sensor may be configured by a body temperature sensor other than an IC, such as a thermocouple.

[0152] (4) In the deep body temperature measuring probe 4 according to the fourth embodiment, the first region 11 and the second region 12 are thermally separated to form a through hole having a "long hole shape (in top view)" penetrating between the front surface 10a and the back surface 10b of the substrate 10 (see FIG. Figure 8 ) is described. However, the present invention is not limited thereto. For example, Fig.11 (a) and Fig.11 As shown in (b), a structure in which a plurality of dot-shaped through holes penetrating the substrate 10 are arranged in parallel in a "perfect circle shape (in plan view)" instead of a "long hole" may be adopted (variation 4).

[0153] In addition, for example Fig.11 (c) and Fig.11As shown in (d), the air layer 40 may be formed by forming a cavity inside the substrate 10 in the thickness direction and placing air in the cavity (modification 5).

[0154] In addition, if Fig.11 As shown, an air layer 41 may be disposed between the region constituting the first region 11 and the second region 12 and the body temperature sensor 25. The air layer 41 may be formed of a long hole penetrating most of the lateral region of the body temperature sensor 25 as shown in the figure.

[0155] From the second region 12, in the top view of the drawing, an air layer 40 is arranged on the left, an air layer 41 is arranged on the right, and the atmosphere 8 (air layer) is arranged on the upper and lower sides. Similarly, when viewed from the first region 11, in the plan view, the air layer 40 is arranged on the right, and the atmosphere 8 (air layer) is arranged on the left, upper and lower sides. That is, the air layer is arranged around the first region 11 and / or the second region 12.

[0156] If the above structure is adopted, the heat flux between a pair of body temperature sensors arranged on the front and back of the substrate 10 is covered / surrounded by an air layer with low thermal conductivity, so the heat flow cannot be lateral on the plane, but only becomes an ideal longitudinal heat flux, and the accuracy of the deep body temperature that can be measured is further improved. In addition, if a long hole is formed to cover / seamlessly surround the area around the body temperature sensor as much as possible (if possible, on four sides), it becomes a more ideal longitudinal heat flux only, and the accuracy of the deep body temperature that can be measured is further improved. In addition, a heat insulating paper 31 with a thermal conductivity roughly equal to that of air can also be arranged on each air layer 40, 41.

[0157] in addition, Fig.10 1 and 2 are cross-sectional views showing main parts of the deep body temperature measurement probes 6 and 7 according to Modification 2 and Modification 3. Fig.11 It is a diagram for explaining the deep body temperature measurement probes 4 ′ and 4 ″ according to the fourth and fifth modified examples. Fig.11 (a) is a top view of the deep body temperature measurement probe 4'. Fig.11 (b) means Fig.11 (a) is a cross-sectional view of the deep body temperature measurement probe 4' at the EE section. Fig.11 (c) is a top view of the deep body temperature measurement probe 4", Fig.11 (d) means Fig.11 (c) is a cross-sectional view of the deep body temperature measurement probe 4" at the FF cross section.

[0158] Explanation of symbols

[0159] 1, 2, 3, 4, 4', 4", 5, 6, 7...probe for measuring deep body temperature; 8...atmosphere; 9...substrate; 9a...surface of the subject; 9b...middle part of the subject; 9c...deep part of the subject; 10...substrate; 10a...surface (of the substrate); 10b...back side (of the substrate); 11...first area; 12...second area; 13...wiring pattern (in a broad sense); 13a...wiring pattern (in a narrow sense); 13b...pad; 13c...terminal; 15...through hole; 17...another through hole; 21, 22...body temperature sensor for the first area; 23, 24...body temperature sensor for the second area; 25...body temperature sensor; 28...external connection terminal; 29... Hot pad; 30…air layer; 31…insulating paper; 32…vacuum or near-vacuum state; 37…metal; 40, 41…air layer; 51…solder; 109a…surface of substitute object; 110…first heat flow measurement system; 110a…first heat flow; 115…first heat flow path; 120…second heat flow measurement system; 120a…second heat flow; 125…second heat flow path, 130…water bath; 131…temperature sensor; 133…aluminum barrel; 200…temperature measurement unit; 210…deep temperature estimation unit; 211…processor; 212…memory; 214…input / output interface; 215…communication interface; 500…deep thermometer.

Claims

1. A probe for measuring deep body temperature, used when measuring the deep body temperature of a subject, characterized in that: include: substrate; a pair of first region temperature sensors, which are a pair of temperature sensors installed facing each other in the first region of the substrate with the substrate interposed therebetween; as well as a pair of second region temperature sensors, which are a pair of temperature sensors installed facing each other in the second region of the substrate with the substrate interposed therebetween, A through hole is formed on the substrate directly below the first region temperature sensor and passes through the front surface and the back surface of the substrate, and the pair of first region temperature sensors are connected via the through hole.

2. The deep body temperature measuring probe according to claim 1, characterized in that: An air layer is arranged inside the through hole.

3. The deep body temperature measuring probe according to claim 2, characterized in that: Heat insulation paper is further arranged inside the through hole.

4. The deep body temperature measuring probe according to claim 1, characterized in that: The substrate is composed of a glass substrate. The interior of the through hole is in a vacuum state or a state close to a vacuum state.

5. The deep body temperature measuring probe according to any one of claims 1 to 4, characterized in that: On the substrate, another through hole is formed directly below the second area temperature sensor, penetrating between the front and back surfaces of the substrate, and metal is buried in the other through hole. The pair of second area temperature sensors are connected via the metal.

6. The deep body temperature measuring probe according to any one of claims 1 to 5, characterized in that: In the substrate, an air layer is arranged between the first region and the second region.

7. The deep body temperature measuring probe according to any one of claims 1 to 6, characterized in that: In the substrate, an air layer is arranged around the first region and / or the second region.

8. The deep body temperature measuring probe according to any one of claims 1 to 7, characterized in that: In the substrate, a temperature sensor for measuring an outside air temperature is arranged adjacent to regions constituting the first region and the second region.

9. A probe for measuring deep body temperature, used when measuring the deep body temperature of a subject, characterized in that: include: plate-like substrate; A first heat flow measurement system comprising a pair of temperature sensors mounted opposite to each other in a first region of the substrate across the substrate, namely, a "pair of first region temperature sensors", and a first heat flow path formed in the substrate in the first region for a first heat flow out of the object; as well as a second heat flow measurement system comprising a pair of temperature sensors (i.e., a pair of second region temperature sensors) mounted opposite to each other in a second region of the substrate across the substrate, and a second heat flow path formed in the substrate in the second region for measuring a second heat flow from the object to be tested, A through hole is formed on the substrate directly below the first area temperature sensor and passes through the front and back surfaces of the substrate, and the first heat flow path is composed of an air layer arranged inside the through hole.

10. The deep body temperature measuring probe according to claim 9, characterized in that: Heat insulation paper is further arranged inside the through hole.

11. A deep body thermometer, characterized in that: include: The deep body temperature measuring probe according to any one of claims 1 to 10; as well as The deep body temperature estimating unit estimates the deep body temperature using the temperatures measured by the pair of first area temperature sensors and the pair of second area temperature sensors of the deep body temperature measuring probe.

12. The deep body thermometer according to claim 11, characterized in that: When the deep body temperature is set to TB, and the temperature measured by the sensor of the pair of first-region temperature sensors disposed on the side of the subject, the sensor of the pair of second-region temperature sensors disposed on the side of the subject, and the temperature measured by the sensor of the pair of first-region temperature sensors disposed on the opposite side of the subject and the sensor of the pair of second-region temperature sensors disposed on the opposite side of the subject are respectively set to T1, T2, T3, and T4, The deep body temperature estimation unit The thermal resistance ratio K of the first heat flow path between the pair of first area temperature sensors and the second heat flow path between the pair of second area temperature sensors is predetermined by the relationship K=[(TB-T2)(T1-T3)] / [(TB-T1)(T2-T4)], and The temperatures T1, T2, T3 and T4 measured by detecting the object to be tested, The deep body temperature TB is estimated by applying the relationship of TB=T1+(T1-T2)(T1-T3) / [K(T2-T4)-(T1-T3)].

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