JP2012098038A - Temperature measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve accuracy in measuring a temperature at a deep portion.SOLUTION: A temperature measurement device includes a temperature measurement unit 43, an arithmetic logical unit 74, and a control unit 73 for controlling operations of the temperature measurement unit and the arithmetic logical unit. The temperature measurement unit 43 includes: a base material 40 having a first surface which is a surface contacting with an object to be measured, and a second surface which faces the first surface and is a surface on the surroundings side; a first temperature sensor 50; a second temperature sensor 52; a surrounding temperature acquisition unit 53; and a heat flow control unit 61 provided on the second surface which is the surface of the base material 40 on the surroundings side. The heat flow control unit 61 performs heat exchange with the surroundings so as to make a temperature on the second surface of the base material come closer to a temperature of the surroundings, compared with the case where the heat flow control unit is absent. The first temperature sensor 50 and the second temperature sensor 52 perform multiple measurements of a first temperature and a second temperature, respectively, under the conditions that a third temperature is different. The arithmetic logical unit 74 calculates a deep portion temperature Tc in a deep portion of the object to be measured, on the basis of an operation expression for the deep portion temperature.

Description

  The present invention relates to a temperature measurement device and the like.

  For example, biological information such as health status, basal metabolic status, and mental status can be obtained from body temperature, which is basic vital information. When estimating the health state, basal metabolic state, or mental state of a person or animal based on the body temperature of the human body or animal, information on the temperature of the deep part (depth part temperature) is required instead of the temperature of the surface layer part.

  Also, for example, when measuring the temperature inside a furnace, piping, etc., if the internal temperature (that is, deep temperature) can be measured by a temperature measuring device provided outside the furnace, piping, the temperature measuring device is connected to the furnace or piping. The construction for installing the inside of the temperature measuring device becomes unnecessary, and the temperature measuring device is not corroded by the internal material.

  A thermometer that measures the deep temperature is described in Patent Document 1, for example. In Patent Document 1, two temperature measurement units (a first temperature measurement unit and a second temperature measurement unit) are arranged in parallel with a distance L on the human body. A first heat insulating material is provided on the environment (atmosphere) side of the first temperature measuring unit, and a second heat insulating material is also provided on the environment (atmosphere) side of the second temperature measuring unit. By making the material of the heat insulating material different from the material of the first heat insulating material, the thermal resistance values of the two temperature measuring units are made different, thereby generating two different heat fluxes. The first temperature measurement unit measures the first body surface temperature and the first intermediate temperature, and the second temperature measurement unit measures the second body surface temperature and the second intermediate temperature. Then, using these four points of temperature data, the deep temperature is measured by a predetermined arithmetic expression.

  That is, with respect to the first heat flux, attention is paid to the fact that the heat flux flowing through the first temperature measurement unit is equal to the heat flux from the deep part of the human body to the body surface, whereby the deep part temperature and the measured temperature are measured. And the first equation relating thermal resistance is obtained. Similarly, for the second heat flux, a second equation is obtained that relates the depth temperature to the measured temperature and thermal resistance. By solving the simultaneous equations, even if the thermal resistance value of the human body is unknown, the deep temperature can be obtained with high accuracy.

JP 2006-308538 A

  In the technique described in Patent Document 1, the heat balance between the temperature measurement unit and the surrounding environment (atmosphere) is not considered in calculating the deep temperature. That is, the technique described in Patent Document 1 is based on the premise that an ideal system that does not generate a heat balance can be formed.

  However, when further miniaturization of the temperature measurement unit is promoted, for example, the heat balance between the side surface of the temperature measurement unit and the environment (atmosphere) becomes obvious, and the measurement error corresponding to the difference in the heat balance is reduced. It cannot be ignored. In this respect, a slight measurement error cannot be denied.

  According to at least one aspect of the present invention, it is possible to measure the deep temperature more accurately.

  (1) One aspect of the temperature measurement device of the present invention includes a temperature measurement unit, an environmental temperature acquisition unit, a calculation unit, and a control unit that controls operations of the temperature measurement unit and the calculation unit, The temperature measurement unit has a first surface as a contact surface that contacts the object to be measured, and a first temperature sensor that measures the temperature at the first measurement point of the substrate as the first temperature. A second temperature sensor for measuring a temperature at a second measurement point different from the first measurement point of the substrate as a second temperature, and a surface facing the first surface of the substrate, A heat flow control unit provided on a second surface which is a surface on the environment side, the environmental temperature acquisition unit acquires a temperature of the environment around the substrate as a third temperature, The one measurement point and the second measurement point are on the outer surface of the substrate or on the substrate. The heat flow control unit is positioned in a portion so that the temperature on the second surface of the base material is closer to the third temperature, which is the temperature of the environment, than in the case where the heat flow control unit is not provided. The first temperature sensor and the second temperature sensor perform a plurality of the first temperature and the second temperature under the condition that the third temperature value is different. The calculation unit is configured to measure the first temperature and the second temperature obtained by the plurality of measurements, and the third temperature having the different value corresponding to the plurality of measurements. A deep temperature in the deep portion of the measured object, which is away from the first surface, is obtained based on an arithmetic expression for the deep temperature.

  In the conventional example, under the condition that the environmental temperature is constant, two different heat fluxes are generated by different types of heat insulating materials in the two temperature measurement units. However, in this aspect, the environmental temperature is Generate heat flux in at least two different systems. In addition, although the term environment is used in the following description, the environment is, for example, a heat medium such as the atmosphere, and can be restated as an ambient medium or an environmental medium.

  In the heat flow model in the conventional example, the environmental temperature Tout in the two temperature measurement systems has the same value (that is, constant). The heat flow generated between the deep temperature Tc and the environmental temperature Tout in each system is constant, and the conventional example assumes this. The fact that the vertical heat flow from the measured object to the environment, for example, is constant means that there is no heat balance that a part of the vertical heat flow escapes to the environment, for example, via the side of the substrate. It is established on the assumption.

  However, when the downsizing of the temperature measuring device is promoted and the size of the base material is reduced, a heat balance (for example, heat escape from the side surface of the base material) between the measurement object and the environment becomes obvious. In this case, the assumption that the heat flow generated between the deep temperature Tc and the environmental temperature Tout is constant is not satisfied.

  On the other hand, in this aspect, in one of the plurality of heat flow systems, one end of each heat flow is an environment in which temperature fluctuation is allowed. For example, in the first system, the environmental temperature is Tout1 (arbitrary temperature). In the second system, the environmental temperature is Tout2 (any temperature different from Tout1). Therefore, there is no restriction as in the conventional example that the heat flow generated between the environmental temperature (Tout) and the deep temperature (Tc) must be constant among a plurality of heat flow systems. That is, the heat flux of each system inherently includes heat transfer due to the heat balance, and the heat balance between the environmental temperature Tout (arbitrary temperature) and the deep temperature Tc of the measured object. Only a heat flow is generated that also contains the components.

  In such a heat flow system model, the temperature at any two points (first measurement point and second measurement point) on the substrate is expressed by an equation including environmental temperature (Tout) as a variable (parameter). Can do.

  Further, when the deep temperature Tc and the environmental temperature Tout are equal, the heat balance is zero. Therefore, for example, when calculating the deep temperature Tc, the measurement error due to the heat balance can be made zero by giving the condition that the deep temperature Tc and the environmental temperature Tout are equal.

  In addition, as the calculation formula for calculating the deep temperature, the temperature obtained from each system when using a calculation formula that takes the difference (ratio) of the temperature information measured based on two heat fluxes with different systems The components included in the information corresponding to the heat balance are offset and disappear. That is, it does not cause any problem that a heat balance is generated between the substrate and the environment, or that a heat balance is generated between the measured object and the environment.

  By such a measurement principle, the deep temperature of the measurement object can be measured with higher accuracy. In general, the effect of the heat balance on the measurement becomes more obvious as the temperature measuring device is made smaller. However, in this aspect, since the error due to the heat balance can be suppressed, the temperature measuring device can be made smaller and extremely high. It is possible to achieve both accurate measurement.

  Further, in the temperature measurement device of this aspect, by performing temperature measurement (acquisition of temperature information) a plurality of times under different environmental temperatures, and performing calculations using the obtained plurality of temperature data, The temperature can be determined. Therefore, basically, it is sufficient to provide one base material, and there is no need to provide two base materials (two temperature measuring units) as in the conventional example described in Patent Document 1. Therefore, also in this respect, the temperature measuring device can be downsized. Moreover, in the thermometer of patent document 1, in order to make the thermal resistance value of each temperature measurement part different, it was necessary to provide the heat insulating material from which a material differs in the surface layer part of a temperature measurement part. Needs only one base material as a heat transfer medium for transferring heat, and in this respect, the configuration of the temperature measuring device can be simplified. As the base material, for example, a material having a predetermined thermal conductivity (or thermal resistance) (for example, silicon rubber) can be used.

  Further, in this aspect, the heat flow control unit is connected to the environment so that the temperature on the second surface of the substrate is closer to the third temperature, which is the temperature of the environment, as compared with the case where there is no heat flow control unit. Perform heat exchange at. When the temperature of the second surface of the substrate changes, both the first temperature Tb, which is the temperature of the first measurement point, and the second temperature Tp, which is the temperature of the second measurement point, change under the influence. However, if the second measurement point is, for example, the measurement point on the environment side, in principle, the second measurement point is considered to be closer to the second surface of the substrate, and the second temperature Tp is The temperature change amount ΔTp of the second temperature Tp is larger than the change amount ΔTb of the first temperature Tb. Therefore, the temperature difference ΔTbp between the first temperature Tb and the second temperature Tp is increased by (ΔTp−ΔTb). That is, according to this aspect, the temperature difference between the first temperature, which is the temperature of the first measurement point, and the second temperature, which is the temperature of the second measurement point, is expanded as compared with the case where the heat flow control unit is not provided. The As a result, the effect of reducing the influence of the error inherently included in the measurement temperature is obtained, and thus the measurement accuracy can be ensured.

  The greater the difference between the first temperature and the second temperature, the higher the depth temperature can be measured. Conversely, the smaller the difference between the first temperature and the second temperature, the more difficult the measurement accuracy can be guaranteed. However, if the downsizing of the temperature measuring unit is promoted, the thickness of the base material becomes thin, and it becomes difficult to clearly distinguish the first temperature and the second temperature, that is, the temperature resolution inside the base material is reduced. There is a tendency to be unable to secure.

  According to this aspect, the second temperature can be brought closer to the temperature of the environment by heat exchange with the environment by the heat flow control unit, and the difference between the first temperature and the second temperature can be expanded. Can be secured. Therefore, even when the temperature measuring unit is further downsized, it is possible to suppress a decrease in measurement accuracy of the deep temperature.

  (2) In another aspect of the temperature measuring device of the present invention, the heat flow control unit is a material layer made of a material having a thermal conductivity different from that of the base material.

  In this aspect, a material layer formed of a material having a thermal conductivity different from that of the base material (preferably a material having a lower thermal conductivity than the base material) on the second surface (environment side surface) of the base material. The material layer is used as a heat flow control unit. For example, silicon rubber can be used as the base material, and a metal layer such as aluminum can be used as the material layer as the heat flow control unit. The heat flow control unit can be formed simply by providing a material layer on the second surface of the substrate. Therefore, the invention of this aspect is easy to realize.

  (3) In another aspect of the temperature measuring device of the present invention, the heat flow control unit further includes a temperature control unit that variably controls the temperature of the material layer.

  In this aspect, the heat flow control unit includes a temperature control unit in addition to the material layer. As the temperature control unit, for example, electronic components such as Peltier elements, coil heaters, air-cooled or water-cooled radiators, and the like can be used.

  In the above-described aspect (2), the heat transfer between the heat flow control unit and the environment follows a natural providence (that is, natural heat dissipation / natural heat absorption). Since the temperature of the second surface can be controlled to a desired temperature, a temperature difference can be more reliably provided between the first temperature and the second temperature.

  (4) In another aspect of the temperature measuring device of the present invention, the temperature control unit is a Peltier element having a heat absorbing surface and a heat radiating surface, and the heat absorbing surface or the heat radiating surface is located on the environment side in the material layer. Touching the surface.

  In this embodiment, a Peltier element is used as the temperature control unit. The Peltier element is an electronic component that utilizes the Peltier effect. The Peltier effect is an effect in which heat is transferred and heat is absorbed or dissipated when current is passed through a joint surface formed by joining a P-type semiconductor and an N-type semiconductor, or a joint surface of two different types of metals. . For example, when a direct current is passed through a semiconductor NPN structure, for example, an endothermic phenomenon occurs when a current flows from an N-type semiconductor to a P-type semiconductor, and heat dissipation occurs when a current flows from the P-type semiconductor to the N-type semiconductor. A phenomenon occurs. When the direction of the current is reversed, the heat absorption and heat generation are reversed. The performance of the Peltier element can be expressed by the maximum heat absorption amount, the maximum current, and the maximum voltage.

  The Peltier element is a small electronic component, and has an advantage that high-precision temperature control is possible and noise and vibration are not generated. Therefore, the temperature of the material layer, which is a component of the heat flow control unit, can be managed with high accuracy by positively controlling the temperature using the Peltier element.

  In the above-described aspect (2), the heat transfer between the heat flow control unit and the environment follows a natural providence (that is, natural heat dissipation / natural heat absorption). Since the temperature of the second surface can be controlled to a desired temperature, a temperature difference can be surely provided between the first temperature and the second temperature.

  For example, the heat absorption and heat dissipation of the Peltier element can be controlled by the negative feedback control system so that the difference (Tb−Tp) between the first temperature Tb and the second temperature Tp is a certain value (ΔTQ) or more. If such temperature control is performed, the difference between the first temperature and the second temperature is satisfied while satisfying the premise that the first temperature and the second temperature both change under the influence of the environmental temperature (third temperature). Can be maintained above a desired value.

  The negative feedback control system may be operated at all times, or can be operated only when necessary. For example, the negative feedback control system can be operated at all times to control (Tb−Tp) to be a constant value (ΔTQ).

  Further, when (Tb−Tp) is equal to or larger than a certain value ΔTQ, the negative feedback control system is set in a non-operating state (a state of being left unnatural), and when (Tb−Tp) is less than a certain value ΔTQ, the negative feedback control system is It is also possible to operate so that (Tb−Tp) becomes a constant value (ΔTQ). In this example, the negative feedback control system is used to control (Tb−tp) to be equal to or greater than a certain value (ΔTQ). In this example, it is possible to reduce the power consumption as compared with an example in which the negative feedback control system is always operated.

  In addition, when a metal layer is used as the material layer, for example, if the heat absorption surface / heat radiation surface of the Peltier element is brought into contact with only a partial region of the surface of the metal layer, for example, the thermal conductivity of the metal layer is high. Thus, the temperature of the entire surface of the metal layer can be changed substantially uniformly.

  According to this aspect, the temperature difference between the first temperature and the second temperature is surely enlarged as compared with the case where there is no heat flow control unit. Therefore, the resolution of the temperature in the substrate can be ensured. Therefore, even when the temperature measurement unit is further reduced in size, it is possible to reliably suppress a decrease in measurement accuracy of the deep temperature.

  (5) In another aspect of the temperature measuring device of the present invention, when the first temperature is expressed by a function including the second temperature and the third temperature as variables and including a plurality of constants, The unit calculates the plurality of constants based on the measured first temperature, the second temperature, and the third temperature, and uses the calculated constants to calculate the deep part temperature using an arithmetic expression To calculate the deep temperature of the measured object.

  When the temperature of the measured object changes, the first temperature on the measured object side in the base material changes, and the second temperature in environmental measurement on the base material also changes. Conventionally, attention has been focused only on temperature changes at two points on the substrate starting from such a measured object. In contrast, in this aspect, attention is also paid to a change in temperature in the base material starting from the environment.

  That is, if the temperature of the environment (atmosphere or the like) changes, the second temperature on the environment side of the base material changes, and the first temperature of the measured object on the base material also changes. It was found by computer simulation that the temperature change at two points on the substrate starting from this environment has a predetermined regularity.

  That is, the first temperature can be represented by a function including the second temperature and the third temperature as variables and including a plurality of constants. Further, when the deep temperature (Tc) and the environmental temperature (Tout) are equal, paying attention to the point that the heat balance becomes zero, the equation for calculating the deep temperature can be obtained by modifying the above function.

  However, in order to calculate the deep temperature based on the calculation formula, it is necessary to determine the values of a plurality of constants included in the above function. Therefore, the calculation unit first calculates the values of the above-described plurality of constants based on, for example, each temperature data obtained as a result of a plurality of measurements. Next, the calculation unit calculates a deep temperature by executing a calculation according to a calculation formula using the value of each constant. As a result, an ideal deep temperature from which the influence of the heat balance is removed is obtained.

  (6) In another aspect of the temperature measuring apparatus of the present invention, the first temperature is represented by a first linear function having the second temperature as a variable and having a first slope and a first intercept, The first intercept of the first linear function is represented by a second linear function having the third temperature as a variable and having a second slope and a second intercept, and the plurality of constants are: The first inclination, the second inclination, and the second intercept, the first temperature obtained by the first measurement is Tb1, the second temperature is Tp1, and the third temperature Is Tout1, the first temperature obtained in the second measurement is Tb2, the second temperature is Tp2, the third temperature is Tout2, and the first temperature obtained in the third measurement is Tb3. When the second temperature is Tp3 and the third temperature is Tout3, the calculation unit The first temperature Tb1, the second temperature Tp1, and the third temperature Tout1 obtained by one measurement, and the first temperature Tb2, the second temperature Tp2, and the third temperature Tout2 obtained by the second measurement. And the first gradient, the second gradient, and the second gradient based on the first temperature Tb3, the second temperature Tp3, and the third temperature Tout3 obtained in the third measurement. The measured object value is calculated by calculating the deep temperature using the calculated first slope, the second slope, and the second intercept value. The deep temperature is calculated.

  According to the computer simulation, the first temperature (temperature on the measured object side of the substrate) has linearity with respect to the second temperature (temperature on the environment side of the substrate), and therefore the first temperature is the second temperature. Is a variable, and can be expressed by a first linear function having a first slope and a first intercept. That is, (first temperature) = (first slope) · (second temperature) + (first intercept).

  Further, by computer simulation, the first intercept in the first linear function has linearity with respect to the third temperature (environment temperature), and therefore the first intercept of the first linear function is It has been found that the third temperature is a variable and can be represented by a second linear function having a second slope and a second intercept. That is, it can be expressed as (first intercept) = (second slope) · (third temperature) + (second intercept).

  As a result, it can be expressed as (first temperature) = (first slope). (Second temperature) + (second slope). (Third temperature) + (second intercept). This relational expression corresponds to the “function including the second temperature and the third temperature as variables and including a plurality of constants” described in the above-described aspect (5). Therefore, the “plurality of constants” correspond to “first slope”, “second slope”, and “second intercept” in the above formula. That is, it is necessary to obtain three constant values.

  Therefore, for example, at least three temperature measurements (acquisition of temperature information) are executed, and a set of first temperature, second temperature, and third temperature is obtained for each temperature measurement (acquisition of temperature information). The obtained temperature value is expressed by the above-described function, that is, (first temperature) = (first slope) · (second temperature) + (second slope) · (third temperature) + (second intercept) ) To obtain a three-way simultaneous equation including three variables (first slope), (second slope), and (second intercept). By solving this ternary simultaneous equation, the values of “a plurality of constants”, that is, “first slope”, “second slope”, and “second intercept” can be determined ( However, it is not limited to this method).

(7) In another aspect of the temperature measuring device of the present invention, the computing unit is configured such that the first slope is a, the second slope is c, and the second intercept is d. The values of a, c, d are
The calculation unit calculates the deep temperature Tc,
It is calculated by the first calculation formula as the calculation formula of the deep temperature expressed by

  In this aspect, the “first slope”, “second slope”, and “second intercept” as the plurality of constants described in the above aspect (5) are expressed as a plurality of constants a, c, d. Express.

The function of (first temperature) = (first slope) · (second temperature) + (second slope) · (third temperature) + (second intercept) described above is specifically, It can be expressed as “Tb = a · Tp + c · Tout + d”. Tb is the first temperature, Tp is the second temperature, Tout is the environmental temperature (third temperature), and a, c, and d are constants. Therefore, the ternary simultaneous equations described above can be expressed by the following equations.
Therefore, a plurality of constants (a, c, d) can be obtained by an expression including the above inverse matrix.

  Further, by substituting the obtained values of a, c, and d into the first calculation formula and executing the calculation, the depth temperature Tc is almost ideally corrected and is not affected by the heat balance. Is obtained.

(8) In another aspect of the temperature measuring device of the present invention, the first temperature obtained in the first measurement is Tb1, the second temperature is Tp1, the third temperature is Tout1, and the second measurement When the obtained first temperature is Tb2, the second temperature is Tp2, the third temperature is Tout2, and the value of Tout2 is different from Tout1, Calculation of the deep temperature using the first temperature Tb1 and the second temperature Tp1 obtained in the first measurement, and the first temperature Tb2 and the second temperature Tp2 obtained in the second measurement. The calculation by the second calculation formula as a formula is performed to calculate the deep temperature Tc, and the second calculation formula is:
Represented by

  In this aspect, at least two temperature measurements (acquisition of temperature information) are executed, and the value of the third temperature (environment temperature) Tout is varied in each temperature measurement. When two temperature measurements are performed at different environmental temperatures (third temperatures), the first measurement uses the first heat flux with the start end as the deep part of the measured object and the end as the environment (atmosphere, etc.) This system is constructed. In the second measurement, a second heat flux system is configured in which the start end is the deep part of the measured object and the end is the environment (atmosphere or the like). Since the third temperature (environment temperature) Tout is different in each system, the heat flux of each system is different from each other.

  In these heat flux systems, since the termination is the environment, the concept of difference in heat balance, which is a problem in the conventional example, does not occur. That is, the environmental temperature Tout (Tout1, Tout2) is uniquely determined including the heat balance.

In addition, the thermal characteristics (for example, thermal conductivity) of the base material used are the same in the first heat flux system and the second heat flux system (this is done using a common base material). Because it is, it is natural). That is, the distribution of thermal resistance does not change at all between the first system and the second system. Therefore, when the first measurement point and the second measurement are set on the substrate, (the difference between the temperature of the first measurement point and the second measurement point) / (the depth temperature Tc of the measured object and the temperature of the first measurement point) The difference is the same for both the first heat flux system and the second heat flux system. Therefore, the following formula is established.
When this equation is solved for Tc, the above-described second calculation equation is obtained. Since the concept of the error component ΔTc in the conventional example does not occur, according to the second calculation formula, an almost ideal deep temperature Tc can be obtained.

  That is, since the second calculation formula is an arithmetic formula in the form of taking the ratio of the difference between the temperature information measured based on two heat fluxes with different systems, the second balance formula includes the heat balance included in each temperature information. Corresponding components are offset and disappear. That is, it does not cause any problem that a heat balance is generated between the substrate and the environment, or that a heat balance is generated between the measured object and the environment.

  The second calculation formula looks formally the same as the calculation formula in the conventional example, but the second calculation formula is fundamentally different from the calculation formula in the conventional example. That is, the second calculation formula is a calculation formula derived from the viewpoint that the ratio of the thermal resistance in the base material is the same (common) based on data obtained from the system of two heat fluxes that terminate in the environment. Yes, it is fundamentally different.

  In this aspect, the third temperature (environment temperature) Tout is not directly related to the calculation of the deep temperature Tc itself. However, as described above, Tout1 in the first measurement needs to be different from Tout2 in the second measurement. When Tout1 = Tout2, it is not possible to accurately calculate the deep temperature. Therefore, the third temperature Tout measured by the third temperature sensor is used to check whether a computable condition (a condition that the third temperature in the first measurement and the second measurement is different) is satisfied, that is, calculation. It can be used to determine whether or not

FIG. 1A to FIG. 1D are diagrams for explaining a method for measuring a deep temperature in the first embodiment. 2A to 2D are diagrams showing specific examples of the heat flow control unit. FIG. 3A to FIG. 3C are diagrams showing examples of actually measured temperature data for considering the effect of the heat flow control unit. 4A and 4B are diagrams illustrating an example of a temperature measurement method and an example of a configuration of a temperature measurement device for carrying out the temperature measurement method. 5A and 5B are diagrams showing another example of the temperature measuring method and another example of the configuration of the temperature measuring device for carrying out the temperature measuring method. 6A and 6B are diagrams showing another example of the temperature measuring method and another example of the configuration of the temperature measuring device for carrying out the temperature measuring method. 7 (A) to 7 (C), the relationship between the first temperature and the second temperature under the condition that the environmental temperature is constant, and the relationship applied to the calculation formula for the deep temperature. Figure showing the results of the case FIG. 8A to FIG. 8D are diagrams showing the relationship between the first temperature and the second temperature when the environmental temperature is changed. FIG. 9A to FIG. 9D are diagrams showing a method for measuring a deep temperature in the first embodiment. FIG. 10A to FIG. 10C are diagrams showing examples of the entire configuration of the temperature measuring device. FIGS. 11A and 11B are diagrams for explaining an example of using a temperature measurement device using wireless communication. The figure which shows the measurement procedure of the deep temperature in 1st Embodiment. Diagram showing an example of the calculation result of the deep temperature The figure which shows the other example of the calculation result of deep part temperature The figure which shows the other example of the calculation result of deep part temperature The figure which shows the other example of the calculation result of deep part temperature FIGS. 17A and 17B are diagrams showing an example of the relationship between the temperature distribution inside the substrate and the measurement results. 18A and 18B are diagrams showing another example of the relationship between the temperature distribution inside the substrate and the measurement results. The figure for demonstrating the measuring method of the deep temperature in 2nd Embodiment. 20A and 20B are diagrams for explaining the reason why an error component due to the heat balance is generated in the conventional example shown in Patent Document 1. FIG. FIGS. 21A and 21B are diagrams for explaining the reason why an error component due to the heat balance does not occur in the second embodiment of the present invention. 22 (A) and 22 (B) are diagrams showing a procedure for measuring the depth temperature in the second embodiment and an example of a calculation result of the depth temperature in the second embodiment. 23A to 23E are diagrams for explaining an example of a method for providing a temperature sensor on a base material. 24A to 24C are diagrams for explaining an example of the thermometer described in FIG. 7 of Patent Document 1 (Japanese Patent Laid-Open No. 2006-308538). The figure which shows the contact part model of a thermometer when a heat flux is in a steady state, and the calculation formula of deep part temperature Diagram for explaining measurement error due to heat balance in conventional example

  Before describing the embodiment of the present invention, an arithmetic expression for obtaining a deep temperature described in Patent Document 1 will be briefly described.

  24A to 24C are diagrams for explaining an example of the thermometer described in FIG. 7 of Patent Document 1 (Japanese Patent Laid-Open No. 2006-308538). In FIG. 24A, the contents of FIG. 7 of Patent Document 1 are described as they are. 24B and 24C are auxiliary diagrams newly added this time to explain the operation of the example described in FIG. 7 of Patent Document 1. FIG.

  As shown in FIG. 24A, the thermometer main body 3 is provided on the human body 2. The thermometer body 3 includes a first temperature measuring unit 3A and a second temperature measuring unit 3B. The first temperature measuring unit 3A includes a heat insulating material 37 having a contact surface 300A that contacts the body surface 2A of the human body 2 and a first heat temperature adjusting means provided between the heat insulating material 37 and the outside air. And a heat insulating material 38A as a heat insulating material. The temperature measuring unit 3B includes a heat insulating material 37 having a contact surface 300B that contacts the body surface 2A at a position separated from the contact position of the temperature measuring unit 3A by a distance L, and a heat insulating material as a heat flux adjusting unit. The heat insulating material 38B as a 2nd heat insulating material is provided between 37 and external air. That is, the heat insulating material 37 is common to the first temperature measuring unit 3A and the second temperature measuring unit 3B, and has a common thermal resistance value.

  The first temperature measurement unit 3A determines the temperature of the interface 301A between the body surface sensor 31A as a first reference temperature measurement unit that measures the temperature of the body surface 2A as the first reference temperature, and the heat insulating material 37 and the heat insulating material 38A. And an intermediate sensor 32A as a first reference temperature measurement unit that measures the first reference temperature.

  Further, the temperature measuring unit 3B determines the temperature of the body surface sensor 31B as a second reference temperature measuring unit that measures the temperature of the body surface 2A as the second reference temperature, and the temperature of the interface 301B between the heat insulating material 37 and the heat insulating material 38B. And an intermediate sensor 32B as a second reference temperature measurement unit that measures the second reference temperature. The material of the heat insulating material 38 is different from the material of the heat insulating material 37. Therefore, the thermal resistance values between the first temperature measurement unit 3A and the second temperature measurement unit 3B are different, and different heat fluxes are generated in each temperature measurement unit.

  FIG. 24 (B) shows a simplified structure of the thermometer main body shown in FIG. 24 (A). In FIG. 24C, the thermal resistance and heat flux in the first temperature measurement unit 3A and the second temperature measurement unit 3B shown in FIG. 24B are described.

  As shown in FIG. 24C, the thermal resistance of the surface layer portion of the human body 2 is Rs, and the contact resistance Rt exists at the contact point between the temperature measuring units 3A and 3B and the human body 2. The value of (Rs + Rt) is unknown. Moreover, the thermal resistance of the common heat insulating material 37 is Ru0 (known). Further, the thermal resistance of the heat insulating material 38A provided on the atmosphere side of the first temperature measuring unit 3A is (Ru1 + RV). RV is the thermal resistance of the surface layer portion close to the atmosphere. Further, the thermal resistance of the heat insulating material 38B provided on the atmosphere side of the first temperature measurement unit 3B is (Ru2 + RV).

  In FIG. 24C, the temperatures measured by the body surface sensors 31A and 31B are Tb1 and Tb3, and the temperatures measured by the intermediate sensors 32A and 32B are Tb2 and Tb4.

  As shown by the thick arrow on the left side of FIG. 24C, the first temperature measurement unit 3A has a heat flux from the deep part of the human body 2 toward the interface 301A where the heat insulating material 37 and the heat insulating material 38A are in contact. Arise. This heat flux can be divided into a heat flux Q (s + t) from the deep part (temperature Tcore) of the human body 2 toward the body surface 2A and a heat flux Qu1 toward the interface 301A from the body surface 2A. Also in the second temperature measurement unit 3B, a heat flux is generated from the deep part of the human body 2 toward the interface 301A where the heat insulating material 37 and the heat insulating material 38A are in contact, and this heat flux is deep in the human body 2 (temperature Tcore). Can be divided into a heat flux Q (s + t) from the body surface 2A toward the body surface 2A and a heat flux Qu2 from the body surface 2A toward the interface 301A.

The heat flux can be obtained by dividing the temperature difference between two points by the thermal resistance value between the two points. Therefore, the heat flux Q (s + t) is represented by the following formula (A), the heat flux Qu1 is represented by the following formula (B), and the heat flux Qu2 is represented by the following formula (C).
Q (s + t) = (Tcore−Tb1) / (Rs + Rt) (A)
Qu1 = (Tb1-Tb2) / Ru0 (B)
Qu2 = (Tb3-Tb4) / Ru0 (C)
Here, the heat flux in the human body 2 is equal to the heat flux in the temperature measuring units 3A and 3B. Therefore, Q (s + t) = Qu1 is established, and similarly, Q (s + t) = Qu2 is established.
Therefore, the following formula (D) is obtained from the formula (A) and the formula (B), and the following formula (E) is obtained from the formula (A) and the formula (C).
Tcore = {(Rs + Rt) / Ru0}. (Tb1-Tb2) + Tb1 (D)
Tcore = {(Rs + Rt) / Ru0}. (Tb3-Tb4) + Tb3 (E)
FIG. 25 is a diagram illustrating a contact part model of the thermometer when the heat flux is in a steady state and a calculation formula for the deep temperature. The figure shown on the upper side of FIG. 25 is a diagram in which the contents of FIG. As shown in the upper diagram of FIG. 22, two different heat fluxes (Q (s + t) and Qu1, Q (s + t) and Qu2) are indicated by straight lines having different inclinations. In each heat flux, as described above, the equations (D) and (E), which are the calculation formulas for the deep temperature Tcore, under the condition that the heat flux in the human body 2 is equal to the heat flux in the temperature measuring units 3A and 3B. Is obtained.

Based on the equations (D) and (E), the term {(Rs + Rt) / Ru0} can be removed. As a result, the following formula (F), which is a calculation formula for the deep temperature Tcore, is obtained.
According to this formula (F), the deep temperature Tcore of the human body 2 can be accurately obtained regardless of the thermal resistance value in the human body 2.

  FIG. 26 shows how measurement errors occur due to the heat balance in the conventional example shown in FIG. In FIG. 26, for convenience of explanation, the measured temperatures of the body surface sensors 31A to 32B are denoted as T1 to T4.

  In FIG. 26, the heat balance (transfer of heat) generated between the human body 2 and the environment (here, the atmosphere) 7 or between the temperature measuring units 3A and 3B and the environment 7 is indicated by a thick dashed arrow. Has been. As described above, a heat flux from the deep part of the human body 2 toward the temperature measuring units 3A and 3B is generated. In actual temperature measurement, a part of the heat flux is, for example, from the temperature measuring units 3A and 3B to the environment (atmosphere) 7. For example, heat flows from the environment (atmosphere) 7 into the temperature measuring units 3A and 3B. Since the technique described in Patent Document 1 described above is based on an ideal heat flux that does not generate a heat balance, a slight measurement error cannot be denied in this respect.

  In the formula (F) shown on the lower side of FIG. 26, the depth temperature Tcore in the conventional example is divided into a true depth temperature Tc and an error component ΔTc due to heat balance. In other words, in the measurement method described in Patent Document 1, there is a slight measurement error associated with the heat balance in the measured deep temperature Tcore. If the error component accompanying this heat balance can be removed by, for example, correction calculation or the like, the measurement accuracy of the deep temperature can be further improved.

  Next, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1A to FIG. 1D are diagrams for explaining a method for measuring a deep temperature in the first embodiment. In FIG. 1, only the principal part (temperature measurement part) of the temperature measurement apparatus in this embodiment is described. An example of the overall configuration of the temperature measuring device will be described later with reference to FIG.

  First, reference is made to FIG. The temperature measuring device in the present embodiment includes a base material 40, a first temperature sensor 50 that measures the temperature at the first measurement point p1 of the base material 40 as a first temperature Tb, and a first measurement point of the base material 40. The second temperature sensor 52 that measures the temperature at the second measurement point p2 different from p1 as the second temperature Tp, and the ambient temperature that acquires the temperature of the environment (here, air) 7 around the substrate 40 as the third temperature. The acquisition unit 53 and the heat flow control unit 61 are included.

  The base material 40 is a first surface SR1 that is a contact surface that contacts the object to be measured 6 and a surface that faces the first surface SR1 and is an environment-side surface (that is, the top surface of the base material 40). Two-sided SR2. The first surface SR1 of the substrate 40 is in contact with the surface of the surface layer portion 5 of the measurement object 6. Further, the heat flow control unit 61 is provided on the second surface SR <b> 2 of the base material 40.

  The second surface SR2 of the base material 40 is, for example, a surface parallel to the first surface SR1. The substrate 40 is a heat medium that transfers heat. As the base material 40, for example, a material having a predetermined thermal conductivity (or thermal resistance) (for example, silicon rubber) can be used. As a material of the base material 40, for example, silicon rubber can be used. The body 6 to be measured may be a human body or may be an inorganic structure such as a furnace or piping.

  As the first temperature sensor 50, the second temperature sensor 52, and the third temperature sensor 54, for example, a temperature sensor of a type that converts a temperature value into a resistance value can be used, and the temperature value is converted into a voltage value. It is possible to use a temperature sensor or the like that converts to a temperature sensor. Note that a chip thermistor, a flexible substrate on which a thermistor pattern is printed, a platinum resistance thermometer, or the like can be employed as a type of temperature sensor that converts a temperature value into a resistance value. A thermocouple element, a PN junction element, a diode, or the like can be employed as a type of temperature sensor that converts a temperature value into a voltage value.

  The deep part temperature of the deep part 4 of the measurement object 6 is Tc, and this deep part temperature Tc is the temperature to be measured. In the example of FIG. 1A, a heat flow (heat flux) Qa from the deep part 4 of the measurement object 6 toward the environment 7 is generated, as indicated by a dashed arrow.

  The environment 7 is, for example, a heat medium such as the atmosphere, and can be restated as an ambient medium or an environmental medium. Even in the case where a gas component that is not a constituent component of the atmosphere is included in the medium around the base material 40, the medium can be referred to as the environment (ambient medium, environmental medium) 7. The medium is not limited to gas.

  The first measurement point p1 and the second measurement point p2 can be provided on the outer surface of the base material 40 or inside the base material 40.

  In addition, the heat flow control unit 61 causes the temperature of the second surface SR2 of the base material 40 to be closer to the third temperature Tout that is the temperature of the environment 7 as compared with the case where the heat flow control unit 61 is not provided. Exchange heat with

  Further, the first temperature sensor 50 and the second temperature sensor 52 set the first temperature Tp and the second temperature Tb a plurality of times (here, three times) under the condition that the value of the third temperature Tout is different. taking measurement.

  The temperature Tp (that is, the first temperature) at the first measurement point p1 and the temperature Tb (that is, the second temperature) at the second measurement point p2 both vary under the influence of the deep temperature Tc as the heat source, and the heat flow Fluctuates under the influence of the temperature Tout (that is, the third temperature) of the environment 7 that is the end of the.

For example, when the first temperature Tp _{= T PA,} can be expressed as the second temperature Tb = _{aT PA} + b. a is the slope of the linear function (first slope), and b is the intercept (first intercept). In addition, the first intercept b changes linearly with the environmental temperature (third temperature) Tout. That is, it can be expressed as b = cTout + d. c is the slope of the linear function (second slope), and d is the intercept (second intercept).

  In the present embodiment, the calculation unit included in the temperature measurement unit (not shown in FIG. 1, reference numeral 74 in FIGS. 4 to 6) includes a first temperature (Tb1 to Tb3) obtained by three measurements, and Based on the second temperature (Tp1 to Tp3) and the third temperature (Tout1 to Tout3) having different values corresponding to the three measurements, the depth temperature in the depth 4 of the measured object 6 away from the first surface SR1. Tc is obtained by calculation using a first calculation formula (formula (1)) that is a calculation formula for the deep temperature. That is, Tc = d / (1-ac).

  The first calculation formula (formula (1)) is derived by paying attention to the fact that the heat balance is zero when the deep temperature (Tc) and the environmental temperature (Tout) are equal (for the detailed derivation process) Will be described later). Determining constants a, c, and d from the temperature data obtained by three measurements and substituting them into equation (1), the deep temperature Tc is obtained. This is the method for calculating the deep temperature Tc in this embodiment.

  In the conventional example, under the condition that the environmental temperature is constant, two different heat fluxes are generated by different types of heat insulating materials in the two temperature measurement units. However, in this aspect, the environmental temperature is Generate heat flux in at least two different systems. In addition, although the term environment is used in the following description, the environment is, for example, a heat medium such as the atmosphere, and can be restated as an ambient medium or an environmental medium.

  In the heat flow model in the conventional example, the environmental temperature Tout in the two temperature measurement systems has the same value (that is, constant). The heat flow generated between the deep temperature Tc and the environmental temperature Tout in each system is constant, and the conventional example assumes this. The fact that the vertical heat flow from the measured object to the environment, for example, is constant means that there is no heat balance that a part of the vertical heat flow escapes to the environment, for example, via the side of the substrate. It is established on the assumption.

  However, when the downsizing of the temperature measuring device is promoted and the size of the base material is reduced, a heat balance (for example, heat escape from the side surface of the base material) between the measurement object and the environment becomes obvious. In this case, the assumption that the heat flow generated between the deep temperature Tc and the environmental temperature Tout is constant is not satisfied.

  In contrast, in the present embodiment, one end of each heat flow in a plurality of heat flow systems is an environment in which temperature fluctuation is allowed. For example, in the first system, the environmental temperature is Tout1 (arbitrary temperature). In the second system, the environmental temperature is Tout2 (any temperature different from Tout1). Therefore, there is no restriction as in the conventional example that the heat flow generated between the environmental temperature (Tout) and the deep temperature (Tc) must be constant among a plurality of heat flow systems. That is, the heat flux of each system inherently includes heat transfer due to the heat balance, and the heat balance between the environmental temperature Tout (arbitrary temperature) and the deep temperature Tc of the measured object. Only a heat flow is generated that also contains the components.

  In such a heat flow system, the temperature at any two points (first measurement point and second measurement point) on the substrate can be expressed by an equation including the environmental temperature (Tout) as a variable (parameter). .

  Further, when the deep temperature Tc and the environmental temperature Tout are equal, the heat balance is zero. Therefore, for example, when the deep part temperature Tc is calculated, by giving the condition that the deep part temperature Tc and the environmental temperature Tout are equal, the measurement error due to the heat balance can be made zero, and the above-described first calculation formula (Formula (1)) is obtained.

  Various variations can be considered for the first measurement point p1 (position where the first temperature sensor 50 is provided) and the second measurement point p2 (position where the second temperature sensor 52 is provided). Here, reference is made to FIG.

  The first measurement point p1 and the second measurement point p2 can be set on the surface or side surface of the substrate 40, that is, on the outer surface of the substrate 40, or can be set inside the substrate 40. it can. Also, either one can be set on the surface or side surface of the base material 40, and the other can be set inside the base material 40. In addition, the result of having measured the deep part temperature by changing the 1st measurement point p1 and the 2nd measurement point p2 variously is later mentioned using FIGS.

  In the present embodiment, the first measurement point p1 is a measurement point on the measured object 6 side, and the second measurement point p2 is a measurement point on the environment (atmosphere) 7 side.

  As shown in FIG. 1B, considering the distance from the first surface (contact surface) SR1 in the direction perpendicular to the contact surface SR1 of the substrate 40, the distance of the first measurement point p1 is LA, The distance of the second measurement point p2 is LB. The height of the base material 40 (the distance from the first surface SR1 to the second surface SR2) is LC.

  For the distance LA and the distance LB, 0 ≦ LA and LB ≦ LC are satisfied, and LA ≦ LB is satisfied. That is, the distances LA and LB of the first measurement point p1 and the second measurement point p2 from the first surface SR1 of the base material 40 are 0 or more, and the height of the base material 40 (the height at the top) is LC. Is within. Further, when the distance LA of the first measurement point p1 from the first surface SR1 of the substrate 40 and the distance LB of the second measurement point p2 from the first surface of the substrate 40 are compared, LA <LB Or LA = LB.

  When LA <LB, the first measurement point p1 is located closer to the measured object 6 than the second measurement point p2. When LA = LB, the first measurement point p1 and the second measurement point p2 are in a horizontal line, and there is no superiority or inferiority in distance. However, the first measurement point p1 and the second measurement point p2 are not necessarily at the same position in the space, but are always at different positions. Note that the fact that the deep temperature Tc can be accurately measured even when LA = LB will be described later with reference to FIG.

  Next, reference is made to FIG. In the example of FIG. 1C, the point x1 and the point x2 are in a horizontal line position. However, the minimum distance from the point x1 to the side surface of the base material 40 is L1, while the minimum distance from the point x2 to the side surface of the base material 40 is L2, and L1 <L2. The point x1 is easier to exchange heat with the environment (atmosphere). Therefore, for example, the point x1 can be the second measurement point p2 that is the measurement point on the environment side, and the point x2 can be the first measurement point p1 that is the measurement point on the measured object side.

  Next, the effect obtained by providing the heat flow control unit 61 will be described with reference to FIG. The left diagram in FIG. 1D shows a structure without the heat flow control unit 61, and the right diagram shows a structure in which the heat flow control unit 61 is provided on the substrate 40. In addition, in the center of FIG. 1D, the temperature level of each part is surrounded by a broken line. In the example of FIG. 1D, it is assumed that the deep temperature Tc and the environmental temperature (third temperature) Tout are constant.

  The heat flow control unit 61 makes the temperature of the second surface SR2 of the base material 40 closer to the third temperature (Tout) that is the temperature of the environment 7 as compared with the case where the heat flow control unit 61 is not provided. Exchange heat with

  When the temperature of the second surface SR2 of the base material 40 changes, both the first temperature Tb that is the temperature of the first measurement point p1 and the second temperature Tp that is the temperature of the second measurement point p2 are affected. Change. However, when the second measurement point p2 is the measurement point on the environment 7 side, the second measurement point p2 is considered to be in a position closer to the second surface SR2 of the base material 40 in principle. Therefore, the second temperature Tp is more affected by the temperature change of the second surface SR2 of the base material 40. Therefore, the temperature change amount ΔTp of the second temperature Tp is larger than the change ΔTb of the first temperature Tb. Become. Therefore, the temperature difference ΔTbp between the first temperature Tb and the second temperature Tp is increased by (ΔTp−ΔTb). By such an action, the temperature difference between the first temperature Tb, which is the temperature of the first measurement point p1, and the second temperature Tb, which is the temperature of the second measurement point p2, is larger than when the heat flow control unit 61 is not provided. Is done.

  In the left diagram of FIG. 1D, the first temperature that is the temperature of the first measurement point p1 is Tb1, and the second temperature that is the temperature of the second measurement point Tp1 is Tp1. Let (Tb1-Tp1) be Tx. 1D, the first temperature that is the temperature of the first measurement point p1 is Tb2, and the second temperature that is the temperature of the second measurement point Tp1 is Tp2. Let (Tb2-Tp2) be Ty. At this time, Tx> Ty.

  The larger the difference between the first temperature Tb and the second temperature Tp, the smaller the influence of the error that is inherently included in the measured temperature, and thus the deeper temperature Tc can be measured with higher accuracy. Conversely, as the difference between the first temperature Tb and the second temperature Tp decreases, the measurement accuracy cannot be guaranteed.

  However, when the downsizing of the temperature measuring unit is promoted, the thickness of the base material 40 becomes thin, and it becomes difficult to clearly distinguish the first temperature Tb and the second temperature Tp. There is a tendency that the temperature resolution cannot be secured.

  According to the present embodiment, the heat exchange with the environment 7 by the heat flow control unit 61 causes the temperature of the second surface SR2 of the base material 40 to change closer to the environmental temperature (third temperature) Tout. Since the difference between the first temperature Tb and the second temperature Tp can be increased, the resolution of the temperature in the substrate 40 can be ensured. Therefore, even when the temperature measurement unit is further downsized, it is possible to suppress a decrease in measurement accuracy of the deep temperature Tc.

  Next, a specific example of the heat flow control unit 61 will be described with reference to FIG. 2A to 2D are diagrams showing specific examples of the heat flow control unit 61. FIG. The type of the heat flow control unit 61 is roughly classified into a passive type and an active type.

  An example of a passive type is shown in FIG. In the example of FIG. 2A, the heat flow control unit 61 is a material layer 63 made of a material having a thermal conductivity different from that of the base material 40. That is, the second surface (environment-side surface) SR2 of the base material 40 is made of a material having a thermal conductivity different from that of the base material 40 (preferably a material having a lower thermal conductivity than the base material 40). The material layer 63 is provided, and this material layer 63 is used as the heat flow control unit 61. For example, silicon rubber can be used as the material of the base material 40, and a material having a higher thermal conductivity than silicon rubber, for example, a metal layer such as aluminum, can be used as the material layer as the heat flow control unit 61. The thickness Tz of the metal layer 63 is preferably thin. The thickness Tz of the metal layer 63 can be set to, for example, about 0.1 mm to 2 mm.

  An example of the active type is shown in FIG. In the example of FIG. 2B, a Peltier element 510 as a temperature control unit is added as a component of the heat flow control unit 61. That is, the heat flow control unit 61 is configured by the material layer 63 made of metal or the like and the Peltier element 510 as the temperature control unit.

  In the passive type, the heat exchange between the heat flow control unit and the environment follows a natural providence. However, in the active type, the temperature of the second surface SR2 of the substrate 40 can be positively determined to a desired temperature. Therefore, a temperature difference can be more reliably provided between the first temperature Tb and the second temperature Tp.

  In the active type, the temperature control unit can control the temperature of the second surface SR2 of the base material 40 to a desired temperature, so that a temperature difference between the first temperature Tb and the second temperature Tp is ensured. Can be provided. The temperature control unit is not limited to the Peltier element 510. For example, an air-cooled or water-cooled heater or radiator can be used. Hereinafter, an example in which the Peltier element 510 is used as the temperature control unit will be described.

  The Peltier element 510 is an electronic component using the Peltier effect, and has a heat absorption surface and a heat dissipation surface (see FIG. 2C).

  The Peltier effect is an effect in which heat is transferred and heat is absorbed or dissipated when current is passed through a joint surface formed by joining a P-type semiconductor and an N-type semiconductor, or a joint surface of two different types of metals. . For example, when a direct current is passed through a semiconductor NPN structure, for example, an endothermic phenomenon occurs when a current flows from an N-type semiconductor to a P-type semiconductor, and heat dissipation occurs when a current flows from the P-type semiconductor to the N-type semiconductor. A phenomenon occurs. When the direction of the current is reversed, the heat absorption and heat generation are reversed. The performance of the Peltier element can be expressed by the maximum heat absorption amount, the maximum current, and the maximum voltage.

  The Peltier element is a small electronic component, and has an advantage that high-precision temperature control is possible and noise and vibration are not generated. Therefore, the temperature of the material layer 63 that is a constituent element of the heat flow control unit can be managed with high accuracy by positively controlling the temperature using the Peltier element.

  In the example of FIG. 2B, the heat absorption surface or heat dissipation surface of the Peltier element 510 is in contact with the surface on the environment 7 side in the material layer 63. The temperature of the material layer 63 can be positively controlled by the Peltier element 510. For example, when a metal layer is used as the material layer 63, the heat absorption surface / heat dissipation surface of the Peltier element 510 is, for example, a part of the surface of the metal layer 63 (for example, the second surface that has little influence on temperature measurement). If contact is made only with the region near the periphery of SR2, the thermal conductivity of the metal layer 63 is high, so that the temperature of the entire surface of the metal layer 63 can be changed substantially uniformly.

  In the example of FIG. 2B, the heat absorption of the Peltier element 510 is reduced by the negative feedback control system so that the difference (Tb−Tp) between the first temperature Tb and the second temperature Tp becomes a certain value (ΔTQ) or more. Heat dissipation can be controlled.

  As described above, both the first temperature Tb and the second temperature Tp vary under the influence of the environmental temperature (third temperature Tout), and the temperature is adjusted by the negative feedback control system following the variation. Will be. That is, the difference between the first temperature Tb and the second temperature Tp is desired while satisfying the premise that the first temperature Tb and the second temperature Tp both change under the influence of the environmental temperature (third temperature Tout). It can be maintained above the value of.

  For example, the heat absorption and heat dissipation of the Peltier element can be controlled by the negative feedback control system so that the difference (Tb−Tp) between the first temperature Tb and the second temperature Tp is a certain value (ΔTQ) or more. If such temperature control is performed, the first temperature Tb and the second temperature Tp are satisfied while satisfying the premise that the first temperature and the second temperature both change under the influence of the environmental temperature (third temperature). Can be maintained above a desired value.

  The negative feedback control circuit 560 constituting the negative feedback control system includes a difference calculation unit 520, a comparison unit 530, an error integration unit 540, and a drive current generation unit 550. The difference calculation unit 520 calculates a difference (Tb−Tp) between the first temperature Tb of the base material 40 and the second temperature Tp. The comparison unit 530 compares the difference (Tb−Tp) with the target value (ΔTQ). The error integration unit 540 integrates an error between the difference (Tb−Tp) and the target value (ΔTQ) on the time axis. The drive current generator 550 generates the drive current of the Peltier element 510 so that the difference (Tb−Tp) and the target value (ΔTQ) are equal. The generated drive current is supplied to the Peltier element 510, and thereby heat absorption and heat dissipation in the Peltier element 510 are controlled.

  The negative feedback control circuit 560 may be operated at all times, or can be operated only when necessary. For example, the negative feedback control circuit 560 can be operated at all times to control (Tb−Tp) to be a constant value (ΔTQ).

  Further, when (Tb−Tp) is equal to or greater than a certain value ΔTQ, the negative feedback control circuit 560 is inactivated, and when (Tb−Tp) is less than the certain value ΔTQ, the negative feedback control circuit 560 is operated. , (Tb−Tp) can be controlled to be a constant value (ΔTQ). In the case of adopting such a configuration in which the negative feedback control circuit 560 is operated only when necessary, for example, an operation availability determination unit 561 (a functional block indicated by a broken line in FIG. 2B) is provided. The operation availability determination unit 561 can determine whether the negative feedback control circuit 560 can operate.

  The operation availability determination unit 561 determines whether (Tb−Tp) is less than a certain value (ΔTQ) (that is, whether (Tb−Tp) <ΔTQ). When (Tb−Tp) is less than a certain value (ΔTQ), the operation availability determination unit 561 changes the on / off control signal SS from the inactive level to the active level. As a result, the negative feedback control circuit 560 enters an operating state. As described above, the negative feedback control circuit 560 controls the heat absorption and heat dissipation of the Peltier element 510 so that (Tb−Tp) becomes a constant value (ΔTQ). When (Tb−Tp) is equal to or greater than a certain value (ΔTQ), the operation availability determination unit 561 sets the on / off control signal SS to an inactive level. As a result, the negative feedback control circuit 560 enters a non-operating state. The material layer (metal layer) 63, which is a component of the heat flow control unit 61, is left in a natural state, and the temperature of the material layer (metal layer) 63 naturally changes according to the natural providence.

  In this way, control that maintains (Tb−tp) at a certain value (ΔTQ) or more can be realized by cooperation between the operation availability determination unit 561 and the negative feedback control circuit 560. In this example, an effect that power consumption can be reduced is obtained as compared with an example in which the negative feedback control circuit 560 is always operated.

  In the example shown in FIG. 2B, when the environmental temperature (third temperature) Tout varies, the first temperature Tb and the second temperature Tp of the base material 40 also change corresponding to Tout, and negative feedback. By the negative feedback control by the control circuit 560, the temperature of the second surface SR2 of the substrate 40 is controlled so that the difference between the first temperature Tb and the second temperature Tp becomes a predetermined value ΔTQ.

  Therefore, even when the temperature resolution between the first measurement point p1 and the second measurement point p2 on the base material 40 is small (that is, when there is not much difference in temperature in the natural state), the second temperature Tp is set to the second temperature Tp. It can be forcibly separated from one temperature Tb. Therefore, it can suppress that the temperature difference between 1st temperature Tb and 2nd temperature Tp becomes extremely small.

  An example of the configuration of the Peltier element 510 is shown in FIG. The upper view of FIG. 2C is a plan view, and the lower view is a side view.

  The Peltier element 510 includes a first metal plate 511, a second metal plate 512, P-type semiconductor layers 514a and 514c, and an N-type semiconductor layer provided between the first metal plate 511 and the second metal plate 512. 514b and 514d and terminals 513a and 513b. As described above, when a current flows from the N-type semiconductor to the P-type semiconductor, an endothermic phenomenon occurs at the junction, and when a current flows from the P-type semiconductor to the N-type semiconductor, a heat dissipation phenomenon occurs at the junction. To do. The heat absorption amount / heat radiation amount can be changed by adjusting the drive current amount. Further, by changing the direction (polarity) of the drive current, heat absorption and heat dissipation can be reversed.

  FIG. 2C shows another configuration example of the temperature control unit. In the example shown in FIG. 2C, the negative feedback control circuit 560 shown in the example of FIG. 2B is not used. That is, on / off (operation / non-operation) of the drive current generation unit 550 is directly controlled by the on / off control signal SS output from the operation availability determination unit 561.

  In the example of FIG. 2C, the drive current generation unit 550 is, for example, a constant current source (but is not limited to this). Generate. The operation availability determination unit 561 changes the on / off control signal SS from the inactive level to the active level when (Tb−Tp) is less than a certain value (ΔTQ). As a result, the drive current generator 550 is activated, and a drive current (for example, a constant current) is supplied to the Peltier element 540. Further, when (Tb−Tp) is equal to or greater than a certain value (ΔTQ), the operation availability determination unit 561 changes the on / off control signal SS from the active level to the inactive level. As a result, the drive current generation unit 550 enters a non-operating state. By such a circuit operation, it is possible to realize control for keeping (Tb−tp) at a certain value (ΔTQ) or more.

  In the example shown in FIG. 2C, since the circuit configuration is simpler than that in the example shown in FIG. 2B, the exclusive area and power consumption of the control circuit can be further reduced.

  The external dimensions of the Peltier element 510 shown in FIG. 2D are determined by the parameters Lc, Wc, Lh, Wh, and H. Lc is, for example, 2.8 mm, Wc is, for example, 2.5 mm, Lh is, for example, 3.6 mm, and H is, for example, 0.8 mm.

  Next, the effect of the heat flow control unit will be considered using the actually measured temperature data example shown in FIG. FIGS. 3A to 3C are diagrams showing examples of actually measured temperature data for considering the effect of the heat flow control unit. FIG. 3A shows an example of temperature data in an example of the base material 40 alone (in the case of no heat flow control unit). FIG. 3B shows an example of temperature data in an example in which a heat insulating material 61 a as a heat flow control unit is provided on the base material 40. FIG. 3C shows an example of temperature data in an example in which a metal layer (aluminum layer) 61 b as a heat flow control unit is provided on the base material 40. In each example shown in FIG. 3, a human body is assumed as the measured body 6, and the temperature Tc of the deep portion 4 is set to 37 ° C. In this experiment, polyvinyl chloride (PVC) is used as the material of the structure corresponding to the surface layer portion 5. The thermal conductivity of polyvinyl chloride is 0.144283 (W / m · K).

  The thickness of the PVC structure (a rectangular parallelepiped) corresponding to the surface layer portion 5 is set to 20 mm. In addition, a base material 40 made of silicon rubber and having a cylindrical shape is provided at the center of the upper surface of the PVC structure. The thermal conductivity of silicon rubber is 0.05 (W / m · K).

  Moreover, the cross section of the base material 40 is circular, and the diameter of the circle is 20 mm. Moreover, the height of the base material 40 is 2 mm. The first temperature sensor 50 and the second temperature sensor 52 are provided at two positions (first measurement point and second measurement point) on the perpendicular L1 perpendicular to the bottom surface (that is, the contact surface) SR1 of the base material 40. ing. The distance between the first temperature sensor 50 and the second temperature sensor 52 is 2 mm. That is, the first measurement point is set on the bottom surface (contact surface) SR1 of the base material 40, and the second measurement point is set on the top surface SR2 of the base material 40.

In the example of FIG. 3B, a heat insulating material (the same material as the base material 40: silicon rubber) 61a is provided as a heat flow control unit. The heat insulating material 61a as the heat flow control unit has a thickness of 2 mm. In the example of FIG. 3C, an aluminum layer 61b as a heat flow control unit is provided.
The aluminum layer 61b as the heat flow control unit has a thickness of 2 mm. The thermal conductivity of the aluminum layer 61b is 192.163 (W / m · K).

  The first temperature Tb and the second temperature Tp are measured n times under the condition that the environmental temperature (third temperature) Tout is different. Here, three temperature measurements are performed. The first measurement data is Tout1, Tb1, Tp1, the second measurement data is Tout2, Tb2, Tp2, and the third measurement data is Tout3, Tb3, Tp3.

  In the example of FIG. 3A, Tout1 is 23 ° C., Tout2 is 30 ° C., and Tout3 is 35 ° C. Tb1 is 29.2884 ° C., Tb2 is 33.1442 ° C., and Tb3 is 35.8983 ° C. Tp1 is 27.4605 ° C., Tp2 is 32.2303 ° C., and Tb3 is 35.6327 ° C.

  The difference between Tb1 and Tp1 (ΔTbp1) is 1.8279, the difference between Tb2 and Tp2 (ΔTbp2) is 0.9139, and the difference between Tb3 and Tp3 (ΔTbp3) is 0.2611. .

  In the example of FIG. 3B, Tout1 is 23 ° C., Tout2 is 30 ° C., and Tout3 is 35 ° C. Tb1 is 29.2884 ° C., Tb2 is 33.1442 ° C., and Tb3 is 35.8983 ° C. Tp1 is 27.8947 ° C., Tp2 is 32.4473 ° C., and Tb3 is 35.6992 ° C.

  The difference between Tb1 and Tp1 (ΔTbp1) is 1.575, the difference between Tb2 and Tp2 (ΔTbp2) is 0.7875, and the difference between Tb3 and Tp3 (ΔTbp3) is 0.225. .

  Comparing ΔTbp in the examples of FIGS. 3A and 3B, in the example of FIG. 3B (an example in which a heat insulating material 61a as a heat flow control unit is provided), the first temperature Tb and the second temperature The difference (ΔTbp) from Tp is smaller than ΔTbp in the example of FIG. In other words, the result is opposite to the desired result.

  In the example of FIG. 3C, Tout1 is 23 ° C., Tout2 is 30 ° C., and Tout3 is 35 ° C. Tb1 is 28.7742 ° C, Tb2 is 32.8871 ° C, and Tb3 is 35.8249 ° C. Tp1 is 26.4583 ° C, Tp2 is 31.7292 ° C, and Tb3 is 35.494 ° C.

  The difference between Tb1 and Tp1 (ΔTbp1) is 2.3159, the difference between Tb2 and Tp2 (ΔTbp2) is 1.1579, and the difference between Tb3 and Tp3 (ΔTbp3) is 0.3309. .

  On the right side of the table shown on the lower side of FIG. 3C, the expansion ratio (%) of the temperature difference Tbp with respect to the example of FIG. 3A and the example of FIG. 3B is shown. Compared with the example of FIG. 3A, ΔTbp1 is enlarged 26.70%, ΔTbp2 is enlarged 26.70%, and ΔTbp3 is enlarged 26.73%.

  3B, ΔTbp1 is enlarged by 47.04%, ΔTbp2 is enlarged by 47.03%, and ΔTbp3 is enlarged by 47.07%.

  From the measured data shown in FIG. 3 (C), when the metal layer is used as the heat flow control unit, the temperature difference between the first temperature Tb and the second temperature Tp in the base material 40 is remarkably enlarged. I understand.

  Next, using FIG. 4 to FIG. 6, it is guaranteed that “the first temperature Tb and the second temperature Tp are measured multiple times under the condition that the value of the third temperature (environment temperature Tout) is different”. An example of a measurement method for doing this will be described.

  4A and 4B are diagrams illustrating an example of a temperature measurement method and an example of a configuration of a temperature measurement device for implementing the temperature measurement method.

The temperature measurement device shown in FIG. 4A includes a temperature measurement unit 43, an environmental temperature acquisition unit 53, a calculation unit 74, and a control unit 73 that controls the operation of the temperature measurement unit 43 and the calculation unit 74. Including.
In the example of FIG. 4A, the environmental temperature acquisition unit 53 includes a wireless communication unit CB. Therefore, information on the environmental temperature (third temperature) can be acquired from the external air conditioner 57 by wireless communication. The environmental temperature acquisition unit 53 can measure the environmental temperature (third temperature) by the environmental temperature sensor (third temperature sensor) 54 by itself.

  The air conditioner 57 includes an atmospheric temperature sensor 55 and a wireless communication unit CA. The control unit 73 includes a calculation unit 74 and a measurement timing control unit 75. The measurement timing control unit 75 outputs a timing control signal ST1, and by this timing control signal ST1, the measurement timing of the first temperature Tb and the second temperature Tp by the first temperature sensor 50 and the second temperature sensor 52, and the environment The acquisition timing of the third temperature Tout by the temperature acquisition unit 53 is controlled.

  As shown in FIG. 4B, for the measurement of the first temperature and the second temperature and the acquisition of the environmental temperature information, the first measurement period (first time zone) to the third measurement period (third time). Obi) is provided. The control unit 73 executes temperature measurement or temperature information acquisition a plurality of times for each measurement period, and executes a calculation according to the first calculation formula (formula (1)) based on the obtained data. The deep temperature Tc is obtained.

  As a method for “changing the value of the third temperature (environment temperature Tout)”, paying attention to an active method using an air conditioner and the like, and fluctuation (small fluctuation) of the environment temperature on the time axis, There is a passive method of adjusting the measurement timing, but in the example of FIG. 4, the latter passive method is adopted.

  For example, when measuring the first temperature Tb at the first measurement point p1 of the substrate 40 and the second temperature Tp at the second measurement point p2 of the substrate 40 three times, if the time interval between the measurements is too short, There may be a case where the condition of “measuring three times under different environmental temperatures (third temperature)” cannot be satisfied. Therefore, in this example, the first time period for the first measurement (that is, the first measurement period), the second time period for the second measurement (that is, the second measurement period), and the third time period. And a third time period for measurement (that is, a third measurement period).

  Each time zone (measurement period) can be, for example, 1 minute (a total of 3 time zones is 3 minutes). The first time period (first measurement period) is a period from time t1 to time t4. For example, temperature measurement is performed every 20th. That is, at time t1, time t2, and time t3, three temperature measurements are executed, and nine pieces of data as illustrated are obtained. Then, the first temperature measurement values (Tb1, Tp1, Tout1) are determined by averaging these data (a simple addition average or a weighted average).

  The second time zone (second measurement period) is the time zone from time t4 to time t7. Also in the second time zone, three temperature measurements are performed, and the second temperature measurement value (Tb2, Tp2, Tout2) is calculated by averaging each measurement result (a simple addition average or a weighted average may be used). ) Is determined.

  The third time zone (third measurement period) is a time zone from time t7 to t10. Also in the third time zone, three temperature measurements are performed, and the second temperature measurement values (Tb3, Tp3, Tout3) are calculated by averaging the measurement results (which may be a simple addition average or a weighted average). ) Is determined. The above process is the process of the first step ST1. The term average operation is to be interpreted in the broadest sense.

  Next, in step S2, constants a, c, and d shown in FIG. 1A are calculated based on the obtained data. Next, in step S3, the deep temperature Tc is measured based on the first calculation formula (formula (1)).

  In the example shown in FIG. 4, a plurality of measured values at different environmental temperatures with respect to the first temperature and the second temperature (and the third temperature) without actively changing the temperature of the environment using an air conditioner or the like. The temperature data can be obtained relatively easily.

  FIG. 5A and FIG. 5B are diagrams showing another example of the temperature measuring method and another example of the configuration of the temperature measuring device for carrying out the temperature measuring method. The temperature measuring device shown in FIG. 5A is provided with a timing control information input unit 83 for inputting timing control information for determining the timing for executing a plurality of temperature measurements. The control unit 73, for example, every time the timing control information (here, the measurement instruction trigger TG) is input from the timing control information input unit 83, for example, the first temperature sensor 50, the second temperature sensor 52, and the third The temperature sensor 54 is caused to perform one temperature measurement.

  In the example of FIG. 5, “measuring the first temperature Tb and the second temperature Tp multiple times under the condition that the value of the third temperature (environment temperature Tout) is different” is guaranteed by the user's own action. Is done.

  For example, when the user performs the first measurement, the temperature of the external air conditioner 57 provided outside the temperature measuring device is set to the first temperature, and when a predetermined time elapses from the setting, the timing control information A measurement instruction trigger TG) as timing control information is input via the input unit. As described above, the control unit 73 measures the temperature at the first temperature sensor 50, the second temperature sensor 52, and the third temperature sensor 54, for example, every time the timing control information is input from the timing control information input unit 83. Let it run. The measurement timing is controlled by the measurement timing control unit 75.

  The temperature measurement can be performed, for example, once for each input of timing control information (measurement instruction trigger TG), and a measured value obtained by performing a plurality of temperature measurements for each input of timing control information. You may obtain | require a measured value by averaging. Thereafter, the user inputs the timing control information after setting the temperature of the air conditioner 57 to the second temperature, and then inputs the timing control information after setting the temperature of the air conditioner 57 to the third temperature. To do. For example, the user inputs three times of timing control information.

  When the temperature information for three times is acquired, the calculation unit 74 automatically executes a calculation (calculation based on the calculation formula) for obtaining the deep temperature Tc based on the acquired temperature information. A temperature Tc is determined. The obtained deep temperature Tc is notified (including display, notification by voice, etc.) to the user, for example. In the example of FIG. 5, since the user himself / herself changes the environmental temperature for each measurement, the temperature measuring device itself does not bear the burden of managing the environmental temperature.

  The measurement procedure is as shown in steps S4 to S6 in FIG. The above example is an example.

  FIG. 6A and FIG. 6B are diagrams showing another example of the temperature measuring method and another example of the configuration of the temperature measuring device for carrying out the temperature measuring method. In the example of FIG. 6, the temperature measurement unit includes an environmental temperature adjustment unit CD that can change the temperature of the environment (third temperature). The control unit 73 changes the environmental temperature (third temperature) by the environmental temperature adjustment unit CD every time one temperature measurement is completed.

  The environmental temperature adjusting unit CD has a function of changing the environmental temperature (third temperature Tout). In the example of FIG. 6A, as the environmental temperature adjustment unit CD, for example, the adjuster CC1 having a function of adjusting the set temperature of the external air conditioner 57 provided outside the temperature measuring device by remote control is used. be able to. The operation of the adjuster CC1 is controlled by a control signal ST2 from the measurement timing control unit 75.

  In the example of FIG. 6B, for example, an air flow generation unit (for example, having a function of changing the temperature of the air flow) CC2 provided inside the temperature measurement device is used as the environmental temperature adjustment unit CD. . The airflow generation unit CC2 can be configured by a fan (electric fan), a minute nozzle that ejects an airflow, or the like. The operation of the airflow generation unit CC2 is controlled by a control signal ST3 from the measurement timing control unit 75.

  By using the environmental temperature adjusting unit CD, the environmental temperature Tout can be reliably varied for each measurement. Further, the environmental temperature Tout can be set to an accurate temperature. Further, for example, the difference between the environmental temperature Tout1 during the first measurement and the environmental temperature Tout2 during the second measurement can be set large. The above example is an example.

  Next, the first calculation formula (calculation of the deep temperature Tc using the formula (1) in FIG. 1A) will be specifically described with reference to FIGS.

  7 (A) to 7 (C), the relationship between the first temperature and the second temperature under the condition that the environmental temperature is constant, and the relationship applied to the calculation formula for the deep temperature. It is a figure which shows the result of a case.

  In FIG. 7A, the base material 40, the first temperature sensor 50, and the second temperature sensor 52 constitute a temperature measurement unit 43. The substrate 40 has a first surface (contact surface) SR1 and a second surface (upper surface of the substrate 40) SR2. The temperature measuring unit 43 is, for example, affixed to a measured object 6 (for example, a human body) 6. The first temperature measured by the first temperature sensor 50 is expressed as Tb. The second temperature measured by the second temperature sensor 52 is expressed as Tp.

  FIG. 7B is a diagram showing the relationship between the second temperature Tp and the first temperature Tb. In FIG. 7B, the horizontal axis is Tp, and the vertical axis is the temperature T of the second temperature Tp and the first temperature Tb. When the first temperature Tp changes linearly in a state where the environmental temperature (third temperature Tout) is constant, the second temperature Tb also changes linearly. That is, the first temperature Tb has linearity with respect to the second temperature Tp.

As shown in FIG. 7B, the first temperature Tb is represented by a linear function with the second temperature Tp as a variable. That is, the following formula (2) is established.
Here, a is the first slope and b is the first intercept (or the first offset value), both of which are constants. When Tp is T _PA , Tb = aT _PA + b, and when Tp is T _PB , Tb = aT _PB + b.

FIG. 7C is a diagram showing the results when the temperature data T1 to T4 obtained by the two temperature measurements are applied to the deep temperature calculation formula described above. It is assumed that the first temperature T1 and the second temperature T2 are obtained by the temperature measurement at time t1. Further, it is assumed that the first temperature T3 and the second temperature T4 are obtained by the temperature measurement at the time t2. T1 to T4 are represented by the following formula (3).
Here, each value of Expression (3) is substituted into Expression (4). Expression (4) is a calculation expression for obtaining the deep temperature Tcore, but as described above, includes an error ΔTc due to the heat balance.
As a result, Expression (5) is obtained.
Next, the relationship between the first temperature Tb and the second temperature Tp when the environmental temperature Tout is changed will be considered with reference to FIG. FIGS. 8A to 8D show the relationship between the first temperature and the second temperature when the environmental temperature is changed, and the case where the relationship is applied to the calculation formula for the deep temperature. It is a figure which shows a result.

As shown in FIG. 8A, the fluctuating environmental temperature (third temperature) Tout is measured by a third temperature sensor 54 included in the environmental temperature acquisition unit 53. As described above, when the second temperature Tp is T _PA , it can be expressed as Tb = aT _PA + b. The constant b is a first intercept (first offset value), and the first intercept b has linearity with respect to the environmental temperature (third temperature) Tout.

That is, as shown in FIG. 8B, when Tout varies, the value of the first intercept b changes linearly according to the environmental temperature (third temperature) Tout. Therefore, the relationship of the following formula (6) is established.
Here, c and d are both constants. c is the second slope, and d is the second intercept. When the environmental temperature (third temperature) Tout is Tout1, the first intercept b is b1 (= cTout1 + d), and when the environmental temperature (third temperature) Tout is Tout2, the first intercept b is b2 (= CTout2 + d).

  FIG. 8C shows the relationship between the second temperature Tp and the first temperature Tb (= Tb1) at Tout1, and the relationship between the second temperature Tp and the first temperature Tb (= Tb2) at Tout2. ing. When Tout changes from Tout1 to Tout2, the slope of the linear function (first slope a) does not change, but since the value of the first intercept b changes from b1 to b2, Tp and The linear function indicating the relationship with Tb is shifted in parallel by the difference between b1 and b2.

Thus, the first temperature Tb shows a linear relationship not only with the second temperature Tp but also with the environmental temperature (third temperature) Tout. Substituting the above equation (6) into the equation Tb = aTp + b shown in the above equation (3), the following equation (7) is obtained.
This equation (7) is a function that includes the second temperature Tp and the third temperature Tout as variables and includes a plurality of constants a, b, and c. By this function, the first temperature Tb is related to the second temperature Tp and the third temperature Tout.

Further, when the above formula (6) is substituted into formula (5), formula (8) is obtained.
Here, since heat transfer occurs due to a temperature difference, the error ΔTc due to the heat balance does not occur when the values of the environmental temperature (third temperature) Tout and the deep body temperature Tc are equal. Therefore, in Expression (8), Tout = ΔTc and ΔTc = 0. Then, equation (8) is transformed into equation (1).
This equation (1) indicates the deep temperature Tc that does not include an error due to the heat balance. However, in order to solve equation (1), it is necessary to determine each value of a plurality of constants a, c, d. The plurality of constants a, c, d are associated with each other by the function represented by the above formula (7). In order to obtain the values of the three constants, a ternary simultaneous equation may be solved. Therefore, at least three temperature measurements are performed at different times.

  Here, during the first measurement, Tb1 as the first temperature, Tp1 as the second temperature, and Tout1 as the third temperature are obtained. During the second measurement, Tb2 as the first temperature, second It is assumed that Tp2 as the temperature and Tout2 as the third temperature are obtained, and Tb3 as the first temperature, Tp3 as the second temperature, and Tout3 as the third temperature are obtained in the third measurement.

These nine measurement data can be expressed by the determinant of Equation (9).
Therefore, a plurality of constants a, c, and d can be obtained by Expression (10) including an inverse matrix.
When each value of the plurality of constants a, c, d is determined, each value is substituted into equation (1). Thereby, the deep temperature Tc is obtained.

  FIG. 9 (A) to FIG. 9 (D) are diagrams illustrating a method for measuring a deep temperature in the first embodiment. As shown in FIG. 9A, three temperatures, ie, the first temperature Tb, the second temperature Tp, and the third temperature Tout are measured at least three times. The obtained nine measurement data (Tb1, Tp1, Tout1, Tb2, Tp2, Tout2, Tb3, Tp3, Tout3) can be related by the determinant (9) shown in FIG. 9B. Therefore, the plurality of constants a, c, d can be obtained by the determinant (10) shown in FIG. And the deep part temperature Tc is computable by Formula (1) shown by FIG.9 (D).

  Next, the overall configuration of the temperature measuring device will be described. FIG. 10A to FIG. 10C are diagrams illustrating an example of the entire configuration of the temperature measuring device.

  In the example of FIG. 10A, the first temperature sensor 50 and the second temperature sensor 52 are embedded in the substrate 40. Moreover, the 3rd temperature sensor 54 as the environmental temperature acquisition part 53 is provided on the heat insulating material 20a. The first temperature sensor 50, the second temperature sensor 52, the base material 40, and the third temperature sensor 54 as the environmental temperature acquisition unit 53 constitute the first unit 100.

  The second unit 200 is provided on the heat insulating material 20b. The second unit 200 includes a control unit 73 and a calculation unit 74. In addition, the calculating part 74 can contain a constant calculation part and a deep part temperature calculation part as a functional block. In addition, although not shown, the second unit 200 may be provided with a notification unit (for example, a display unit) that notifies a calculation result.

  10A has a pasting structure 10 for pasting the first surface (contact surface) SR1 of the base material 40 to the surface of the measurement object 6. The affixing structure 10 can be composed of, for example, an adhesive tape. The pressure-sensitive adhesive tape can have a release paper 8 and a support layer (pressure-sensitive adhesive layer) 9.

  The first unit 100 can be affixed to the surface of the measurement object 6 by the affixing structure 10. Therefore, the operability and portability of the temperature measuring device are improved. In addition, for example, when the temperature measuring device is used to measure body temperature of an infant or an infant, since the infant frequently moves the body, the contact between the temperature measuring device and the body surface is determined for a predetermined time, It is difficult to hold well. However, even in such a case, since the entire temperature measuring device can be applied to the surface of the body 6 to be measured using the attachment structure 10, even if an infant or an infant moves the body, Good contact with the temperature measuring device can be maintained. Therefore, accurate and stable temperature measurement is possible.

  In the example of FIG. 10B, the environmental temperature acquisition unit 53 receives environmental temperature information from the atmospheric temperature sensor 55. As the atmospheric temperature sensor 55, for example, a temperature sensor provided in an air conditioner that controls the temperature of the environment can be used (see FIGS. 4 to 6).

  In the example of FIG. 10C, a separate configuration in which the first unit 100 and the second unit 200 are separated is employed. The first unit 100 includes a first wireless communication unit CA, and the second unit 200 includes a second wireless communication unit CB.

  Information on the first temperature (Tb) and information on the second temperature (Tp), or information on the first temperature (Tb), information on the second temperature (Tp), and information on the third temperature (Tout) It is transmitted from the wireless communication unit CA to the second wireless communication unit CB. The computing unit 74 provided in the second unit receives the information on the first temperature (Tb) and the information on the second temperature (Tp) received by the second wireless communication unit CB, or the first temperature (Tb). The calculation is performed based on the information of the second temperature (Tp) and the information of the third temperature (Tout) to obtain the deep temperature Tc of the DUT 6.

  10C, the number of components of the first unit 100 (for example, the main body of the temperature measuring device) can be minimized, and the weight of the first unit 100 can be reduced. . Therefore, for example, even when the first unit 100 is brought into contact with the body surface of the subject as the subject to be measured 6 for a long time, a large burden is not given to the subject. Therefore, for example, it becomes possible to monitor temperature continuously over a long period of time.

  In addition, since the temperature data can be transmitted and received by wireless communication between the first unit 100 and the second unit 200, the second unit 200 can be set apart from the first unit 100 to some extent. It becomes. Further, since wireless communication is used, no communication wiring is required. Therefore, the handleability of the first unit is improved. Further, since the first unit 100 can be completely separated from the second unit 200, the weight reduction of the first unit 100 can be further promoted.

  FIG. 11A and FIG. 11B are diagrams for explaining an example of use of a temperature measurement device using wireless communication. In FIG. 11A, the first unit 100 is attached (attached) to the body surface 6 </ b> A of the infant's chest as the body to be measured 6. The second unit 200 is attached to the left wrist of a guardian (user of the temperature measuring device) MA holding an infant as the body to be measured 6. Here, the 2nd unit 200 shall function also as a display part.

  As shown in FIG. 11B, the first unit 100 includes a first temperature sensor 50, a second temperature sensor 52, a third temperature sensor 54 as an environmental temperature acquisition unit 53, and an A / D conversion unit. 56, a wireless communication unit CA, and an antenna AN1. The second unit 200 includes a wireless communication unit CB, a control unit 73, a calculation unit 74, a display unit 77, an operation unit 79, and a storage unit 81. The operation unit 79 can also serve as the timing control information input unit 83 shown in FIG.

  The calculation unit 74 stores a calculation formula for calculating the above-described plurality of constants a, c, d and a calculation formula for calculating the deep body temperature Tc. The storage unit 81 stores the received first temperature Tb, second temperature Tp, and environmental temperature Tout, and also stores calculated values of a plurality of constants a, c, and d. The obtained deep body temperature Tc is also stored.

  The storage unit 81 is configured to be able to store temperature information related to a plurality of objects to be measured (here, subjects). Therefore, data such as the deep body temperature Tc can be stored for each infant as the subject. In addition to the temperature information, the storage unit 81 may store measurement information such as the name, age, and measurement date and time of the measurement object 6 (here, the infant who is the subject). In this case, the guardian (user of the temperature measurement device) MA can input these measurement information by operating the operation unit 79.

  For example, the temperature measuring device operates as follows. When the parent MA operates the operation unit 79 of the second unit 200, the power of the second unit 200 is turned on. Then, radio waves are transmitted from the wireless communication unit CB. The electromagnetic induction by the radio wave generates an electromotive force in the antenna AN1, and the power (battery) in the first unit 100 is charged by the electromotive force. Then, the first unit 100 is activated, and the first temperature sensor 50, the second temperature sensor 52, and the environmental temperature sensor (third temperature sensor) 54 are activated. Then, the first unit 100 transmits a standby signal toward the second unit 200.

  Next, when receiving the standby signal, the control unit 73 in the first unit 100 instructs the wireless communication unit CB to transmit a temperature measurement start signal. When receiving the temperature measurement start signal, the first unit 100 starts temperature measurement by the first temperature sensor 50, the second temperature sensor 52, and the environmental temperature sensor (third temperature sensor) 54. Note that the measurement of the first temperature Tb and the second temperature Tp is preferably performed in a state where heat transfer from the deep portion of the subject 6 to the body surface 6A is in a steady state (equilibrium state). Therefore, it is preferable to start the temperature measurement at the timing when the time necessary for realizing the equilibrium state has elapsed from the reception timing of the temperature measurement start signal.

  The measured temperature information (the first temperature Tb, the second temperature Tp, and the third temperature Tout) is converted from an analog signal to a digital signal by the A / D conversion unit 56, and is transmitted to the second unit 200 by the wireless communication unit CA. Sent. Temperature measurement is performed a plurality of times, and measurement data is transmitted for each measurement. The execution interval of each measurement can be appropriately adjusted in consideration of the environment (atmosphere, etc.) and trends.

  The computing unit 74 in the second unit 200 temporarily stores a set of data of the first temperature Tb, the second temperature Tp, and the third temperature Tout sent at predetermined intervals in the storage unit 81. When all the necessary temperature data is obtained, a predetermined calculation is executed according to the procedure described above, and the deep temperature Tc of the subject (infant) 6 is measured. The measured deep temperature Tc is displayed on the display unit 77, for example.

  FIG. 12 is a diagram showing a procedure for measuring the deep temperature in the first embodiment. First, temperature data is acquired (step S10). The temperature data includes the first temperature Tb1, the second temperature Tp1, and the third temperature Tout1 obtained by the first measurement, and the first temperature Tb2, the second temperature Tp2, and the third temperature Tout2 obtained by the second measurement. The first temperature Tb3, the second temperature Tp3, and the third temperature Tout3 obtained in the third measurement are included.

  Next, a plurality of constants a, c, d are calculated (step S20). Next, the deep temperature is calculated using the first calculation formula described above (step 30).

(Example of measurement result of deep temperature)
Next, as an example, a data example of the first temperature Tb and the second temperature Tp when the environmental temperature Tout is changed in three stages, and an example of a deep temperature calculated based on the data example (example of calculation result) ) Will be described with reference to FIGS. In the following description, an example in which the heat flow control unit 61 is not used will be described, but the same result can be obtained even when the heat flow control unit 61 is provided.

(Example of FIG. 13)
FIG. 13 is a diagram illustrating an example of a calculation result of the deep temperature. In FIG. 13, a human body is assumed as the body to be measured 6, and the temperature Tc of the deep part 4 is set to 37 ° C. In this experiment, polyvinyl chloride (PVC) is used as the material of the structure corresponding to the surface layer portion 5. The thermal conductivity of polyvinyl chloride is 0.144283.

  The thickness of the PVC structure (a rectangular parallelepiped) corresponding to the surface layer portion 5 is set to 20 mm. In addition, a base material 40 made of silicon rubber and having a cylindrical shape is provided at the center of the upper surface of the PVC structure. The thermal conductivity of silicon rubber is 0.05.

  Moreover, the cross section of the base material 40 is circular, and the diameter of the circle is 20 mm. Moreover, the height of the base material 40 is 2 mm. The first temperature sensor 50 and the second temperature sensor 52 are provided at two positions (first measurement point and second measurement point) on the perpendicular L1 perpendicular to the bottom surface (that is, the contact surface) SR1 of the base material 40. ing. The distance between the first temperature sensor 50 and the second temperature sensor 52 is 2 mm. That is, the first measurement point is set on the bottom surface (contact surface) SR1 of the base material 40, and the second measurement point is set on the top surface SR2 of the base material 40.

In the example of FIG. 13, the heat transfer coefficient in the environment (atmosphere) 7 (a constant proportional to the mobility of heat in the atmosphere) is set to 0.01 W / m ² · K. The environmental temperature (third temperature) Tout, the first temperature Tb, and the second temperature Tp are measured n times. In this example, three temperature measurements are performed. Therefore, n is either 1, 2, or 3.

  Tout1 is 23 ° C., Tout2 is 30 ° C., and Tout3 is 35 ° C. Tb1 is 29.2884 ° C., Tb2 is 33.1442 ° C., and Tb3 is 35.8983 ° C. Tp1 is 27.4605 ° C., Tp2 is 32.2303 ° C., and Tb3 is 35.6327 ° C.

  The measured (calculated) depth temperature is 36.99986 ° C., and includes a slight error compared to the actual depth temperature Tc (= 37 ° C.). That is, it was found that the deep part temperature can be measured with extremely high accuracy using the downsized base material 40.

(Example of FIG. 14)
FIG. 14 is a diagram illustrating another example of the calculation result of the deep temperature. The measurement environment and measurement conditions in the example of FIG. 14 are basically the same as in the example of FIG. However, in the example of FIG. 14, the 1st temperature sensor 50 and the 2nd temperature sensor 52 are provided on the side surface of the base material 40, and the perpendicular L2. The distance between the first temperature sensor 50 and the second temperature sensor 52 is 2 mm.

  Tout1 is 23 ° C., Tout2 is 30 ° C., and Tout3 is 35 ° C. Tb1 is 28.7516 ° C., Tb2 is 32.8758 ° C., and Tb3 is 35.8217 ° C. Tp1 is 26.4822 ° C, Tp2 is 31.6241 ° C, and Tb3 is 35.464 ° C.

  The measured (calculated) depth temperature was 37.00000 ° C., and no error was observed compared to the actual depth temperature Tc (= 37 ° C.). That is, it was found that the deep part temperature can be measured with extremely high accuracy using the downsized base material 40.

(Example of FIG. 15)
FIG. 15 is a diagram illustrating another example of the calculation result of the deep temperature. The measurement environment and measurement conditions in the example of FIG. 15 are basically the same as in the above example. However, in the example of FIG. 15, the first temperature sensor 50 is provided near the center of the contact surface SR <b> 1 of the base material 40, and the second temperature sensor 52 is provided on the side surface of the base material 40.

  Tout1 is 23 ° C., Tout2 is 30 ° C., and Tout3 is 35 ° C. Tb1 is 29.2884 ° C., Tb2 is 33.1442 ° C., and Tb3 is 35.8983 ° C. Tp1 is 26.4822 ° C, Tp2 is 31.6241 ° C, and Tb3 is 35.464 ° C.

  The measured (calculated) depth temperature was 37.00000 ° C., and no error was observed compared to the actual depth temperature Tc (= 37 ° C.). That is, it was found that the deep part temperature can be measured with extremely high accuracy using the downsized base material 40.

(Example of FIG. 16)
FIG. 16 is a diagram illustrating another example of the calculation result of the deep temperature. The measurement environment and measurement conditions in the example of FIG. 16 are basically the same as in the above example. However, in the example of FIG. 16, the first temperature sensor 50 is provided on the upper surface SR <b> 2 of the base material 40. The second temperature sensor 52 is provided on the side surface of the substrate 40. The second temperature sensor 52 is provided on a straight line L3 that passes through the first temperature sensor 50 and is parallel to the contact surface SR2. That is, the first temperature sensor 50 and the second temperature sensor 52 are in a horizontal line position.

  Tout1 is 23 ° C., Tout2 is 30 ° C., and Tout3 is 35 ° C. Tb1 is 28.7516 ° C., Tb2 is 32.8758 ° C., and Tb3 is 35.8217 ° C. Tp1 is 26.4822 ° C, Tp2 is 31.6241 ° C, and Tb3 is 35.464 ° C.

  The measured (calculated) depth temperature was 37.00000 ° C., and no error was observed compared to the actual depth temperature Tc (= 37 ° C.). That is, it was found that the deep part temperature can be measured with extremely high accuracy using the downsized base material 40.

  From the above experimental results, it can be seen that the relative positional relationship between the first temperature sensor 50 and the second temperature sensor 52 is not particularly problematic. That is, the first temperature sensor 50 and the second temperature sensor 52 may be on a vertical line passing through the heat source (the deep portion of the measured object), and the first temperature sensor 50 and the second temperature sensor 52 are aligned horizontally. It may be in the position.

  That is, the first measurement point where the first temperature sensor 50 is provided and the second measurement point where the second temperature sensor 52 is provided are the outer surface of the base material 40 (the contact surface SR1 which is the bottom surface in the above example). , Any one of the upper surface SR2 and the side surface) or the inside of the base material 40. However, in order to calculate the deep temperature using the determinant, at least one set of Tb and Tp corresponding to any one of the environmental temperatures (third temperatures) Tout1, Tout2, and Tout3 is not the same value (Tb ≠ Tp) must be satisfied. That is, it is necessary that at least one set of Tb and Tp has a temperature difference among the three sets of the first temperature Tb and the second temperature Tp. Therefore, the first unit 100 is designed so as to satisfy this condition.

  Next, the relationship between the temperature distribution inside the substrate 40 and the measurement results will be considered. FIG. 17A and FIG. 17B are diagrams showing an example of the relationship between the temperature distribution inside the substrate and the measurement result. The data example shown in FIG. 17A is the same as the data example shown in FIG. FIG. 17B is a diagram showing the temperature distribution in the perpendicular direction of the substrate 40 at Tout1 (= 23 ° C.). In FIG. 17B, the horizontal axis is the distance in the direction of the perpendicular L1 with respect to the contact surface SR1, and the vertical axis is the temperature of the substrate 40. As shown in FIG. 17 (B), the temperature of the base material 40 decreases linearly with distance from the heat source (the deep portion 4 of the measured object 6).

  The data example of FIG. 17 (A) is a result of calculating the deep temperature under the heat distribution of the base material 40 as shown in FIG. 17 (B), and as described above, measurement with extremely high accuracy is performed. The result is obtained.

  18A and 18B are diagrams showing another example of the relationship between the temperature distribution inside the base material and the measurement result. The measurement environment and measurement conditions in the example of FIG. 18A are basically the same as those in the example of FIG. However, in the example of FIG. 18A, the height of the substrate 40 is 20 mm, which is 10 times the height (2 mm) of the substrate 40 in the example of FIG. As described above, when the height of the base material 40 is increased, the area of the side surface of the cylinder increases, so that heat radiation from the side surface of the cylindrical base material 40 increases. The amount of heat released from the side surface changes in accordance with the distance from the heat source (the deep portion 4 of the measured object 6).

  FIG. 18B is a diagram showing a temperature distribution in the perpendicular direction of the substrate 40 at Tout1 (= 23 ° C.). In FIG. 18B, the horizontal axis is the distance in the direction of the perpendicular L1 with respect to the contact surface SR1, and the vertical axis is the temperature of the substrate 40. As shown in FIG. 18 (B), the temperature of the base material 40 decreases with distance from the heat source (the deep portion 4 of the measured object 6), but the characteristic line indicating the temperature distribution is not a straight line, but a curved line. Become. As described above, when the height of the base material 40 is increased, the area of the side surface of the cylinder is increased, the heat radiation from the side surface of the cylindrical base material 40 is increased, and the amount of heat radiation from the side surface is increased. This is because it changes in accordance with the distance from the heat source (the deep portion 4 of the measured object 6).

  The data example of FIG. 18A is a result of calculating the deep temperature under the heat distribution of the base material 40 as shown in FIG. Tout1 is 23 ° C., Tout2 is 30 ° C., and Tout3 is 35 ° C. Tb1 is 29.62274 ° C., Tb2 is 33.311 ° C., and Tb3 is 35.94611 ° C. Tp1 is 23.29526 ° C., Tp2 is 30.14763 ° C., and Tb3 is 35.04218 ° C. The measured (calculated) depth temperature was 37.00000 ° C., and no error was observed compared to the actual depth temperature Tc (= 37 ° C.). That is, it was found that even when the temperature distribution inside the substrate 40 is represented by a curve, the deep temperature can be measured with extremely high accuracy by using the temperature measurement method of the present embodiment. Therefore, there is no restriction on the height of the base material 40, and there is no restriction on the ratio between the area of the contact surface and the height of the base material 40. Therefore, the first unit 100 can be configured quite freely.

(Second Embodiment)
In the present embodiment, a second calculation formula different from the above-described embodiment is used as the deep temperature calculation formula. In this embodiment, temperature measurement (acquisition of temperature information) is performed at least twice.

  FIG. 19 is a diagram for explaining a method for measuring a deep temperature in the second embodiment. As shown in FIG. 19, in the present embodiment, the first measurement and the second measurement are performed, and the environmental temperature (third temperature) Tout1 in the first measurement, and the environmental temperature (third temperature) Tout2 in the second measurement. Make them different.

  The first temperature obtained in the first measurement is Tb1, the second temperature is Tp1, the third temperature is Tout1, the first temperature obtained in the second measurement is Tb2, the second temperature is Tp2, 3 Temperature is Tout2.

The calculation unit 74 uses the first temperature Tb1 and the second temperature Tp1 obtained by the first measurement, and the first temperature Tb2 and the second temperature Tp2 obtained by the second measurement, according to the second calculation formula. An operation is performed to calculate the deep temperature Tc. The second calculation formula is represented by the following formula (11).
When the second calculation formula according to Formula (11) is used, as described above, the value of the environmental temperature (third temperature) Tout2 in the second measurement is different from the environmental temperature (third temperature) Tout1 in the first measurement. Must be a value.

  The reason why the deep temperature can be measured without causing an error component due to the heat balance will be described with reference to FIG. 20 and FIG.

  20A and 20B are diagrams for explaining the reason why an error component due to the heat balance occurs in the conventional example shown in Patent Document 1. FIG. FIG. 20A shows the states of six temperatures (T1, T2, Tt1, T2, T4, Tt2) and thermal resistance in the conventional temperature measurement unit. FIG. 20B shows the state of thermal resistance and heat flux between the environmental temperature (third temperature) Tout and the deep temperature Tc in the temperature measurement unit shown in FIG.

  In the conventional example, two heat flow systems are formed using two temperature measurement units arranged in parallel. In addition, the environmental temperature (third temperature) Tout is constant, and the first heat insulating material 38A and the second heat insulating material 38B provided on the upper surface of the base member 37 allow the temperature measuring unit to Thermally shut off. The heat transfer coefficient in the environment (atmosphere) (a constant proportional to the mobility of heat in the gas) is n. Further, the thermal resistance of the surface layer portion of the measured object is Rb, the thermal resistance of the base material 37 is R1, the thermal resistance of the first heat insulating material 38A is R2, and the thermal resistance of the second heat insulating material 38B is R3.

In the conventional example, two different heat fluxes are formed by differentiating the heat insulating material 38A and the heat insulating material 38B under the assumption that the environmental temperature (third temperature) Tout is constant.
That is, in the conventional example, the relationship of Qb1 = Q11 = Q12 is established between the heat flux Qb1, the heat flux Q11, and the heat flux Q12, and the heat flux Qb2, the heat flux Q21, and the heat flux Q22. And Qb2 = Q21 = Q22.

  However, when the miniaturization of the temperature measuring unit is promoted, the three temperatures (T1, T2, Tt1) of the first system and the three temperatures (T2, T4, Tt2) of the second system are The temperature (third temperature) Tout is affected. Therefore, the premise that Qb1 = Q11 = Q12 and Qb2 = Q21 = Q22 is not satisfied. In this case, the left side of the formula (F) which is the calculation formula of the conventional example is Tc + ΔTc, and a measurement error ΔTc corresponding to the difference in heat balance occurs.

  That is, in the thermometer described in Patent Document 1, the temperature measurement unit is configured to be shielded from the environment (atmosphere) by the heat insulating material provided on the surface layer, and thus the heat flux is the top of the temperature measurement unit. It is designed under the design concept that it can be ignored with little heat balance with the environment (atmosphere). However, if the miniaturization of the thermometer is further promoted, for example, the heat balance between the side surface of the temperature measurement unit and the environment (atmosphere) becomes obvious, and the measurement error corresponding to the difference in the heat balance is ignored. become unable.

  FIGS. 21A and 21B are diagrams for explaining the reason why an error component due to the heat balance does not occur in the second embodiment of the present invention. FIG. 21A shows the state of temperature and thermal resistance in the temperature measurement unit according to the second embodiment. FIG. 21B shows the state of thermal resistance and heat flux between the environmental temperature (third temperature) Tout1, Tout2 and the deep temperature Tc in the temperature measurement unit shown in FIG. .

  In the present embodiment, temperature measurement (acquisition of temperature information) is performed at least twice, and the value of the third temperature (environment temperature) Tout is varied in each temperature measurement (Tout1 ≠ Tout2). When two temperature measurements are performed with different environmental temperatures (third temperatures), the first measurement is the first heat flow in which the start end is the deep part 4 of the measured object and the end is the environment (atmosphere etc.) A bundle system is constructed. In the second measurement, a second heat flux system is configured in which the start end is the deep part of the measured object and the end is the environment (atmosphere or the like). Since the third temperature (environment temperature) Tout is different in each system, the heat flux of each system is different from each other.

  The heat transfer coefficient in the environment (atmosphere) 7 (a constant proportional to the heat mobility in the gas) is n. The first temperature is Tb1 (or T1), Tb2 (or T3). The second temperature is Tp1 (or T2) or Tp2 (or T4). The thermal resistance in the surface layer portion 5 of the measurement object 6 is Rb, and the thermal resistance of the base material 40 is R1. In addition, as shown in FIG. 21B, in the first system, a heat flux Qb1, a heat flux Q11, and a heat flux Qa1 are generated. In the second system, a heat flux Qb2, a heat flux Q21, and a heat flux Qa2 are generated.

  In these two heat flux systems, since the end of the heat flux is the environment 7 in which temperature fluctuation is allowed, the concept of difference in heat balance, which is a problem in the conventional example, does not occur. That is, the environmental temperature Tout (Tout1, Tout2) including the heat balance is simply determined (varies as appropriate).

In addition, the thermal conductivity (that is, thermal resistance) of the base material 40 used is the same in the first heat flux system and the second heat flux system. That is, the distribution of thermal resistance does not change at all between the first system and the second system. Therefore, when the first measurement point and the second measurement are set on the substrate, (the difference between the temperature of the first measurement point and the second measurement point) / (the depth temperature Tc of the measured object and the temperature of the first measurement point) The difference is the same for both the first heat flux system and the second heat flux system. Therefore, the following formula is established.
When this equation (12) is solved for Tc, the above-described second calculation equation (the above equation (11)) is obtained. Since the concept of the error component ΔTc in the conventional example does not occur, according to the second calculation formula, an almost ideal deep temperature Tc can be obtained.

  The second calculation formula (Formula (11)) looks formally the same as the calculation formula (Formula (F)) in the conventional example, but the second calculation formula (Formula (11)) is the calculation of the conventional example. The formula (formula (F)) is a fundamentally different calculation formula. That is, the second calculation formula (formula (11)) is derived from the viewpoint that the ratio of the thermal resistance in the substrate is the same based on the data obtained from the system of two heat fluxes that terminate in the environment. This is a calculation formula and is fundamentally different.

  In the present embodiment, the third temperature (environment temperature) Tout is not directly related to the calculation of the deep temperature Tc itself. However, as described above, Tout1 in the first measurement needs to be different from Tout2 in the second measurement. When Tout1 = Tout2, it is not possible to accurately calculate the deep temperature.

  Therefore, the third temperature Tout3 measured by the third temperature sensor 54 (or the third temperature Tout3 acquired by the environmental temperature acquisition unit 53) is calculated according to the condition that can be calculated (the third temperature in the first measurement and the second measurement). It can be used to check whether or not the calculation is possible.

  FIG. 22A and FIG. 22B are diagrams illustrating a measurement procedure of the depth temperature in the second embodiment and an example of a calculation result of the depth temperature in the second embodiment. First, temperature data is acquired (step S40). The temperature data includes a first temperature Tb1, a second temperature Tp1, and a third temperature Tout1 obtained by the first measurement, and a first temperature Tb2, a second temperature Tp2, and a third temperature Tout2 ( ≠ Tout1). Next, the deep temperature is calculated using the second calculation formula (step S50).

  FIG. 22B is a diagram illustrating an example of the calculation result of the deep temperature in the second embodiment. Here, the measurement environment shown in FIG. 13 is used. When the environmental temperature (third temperature) Tout1 in the first measurement is 23 ° C., the first temperature Tb1 is 28.371 ° C., and the second temperature Tp1 is 26.2482 ° C. When the environmental temperature (third temperature) Tout2 in the second measurement is 30 ° C., the first temperature Tb2 is 32.6855 ° C., and the second temperature Tp2 is 31.6241 ° C. The deep temperature Tc serving as a heat source is set to 37 ° C. The calculation result for this deep temperature was 37.00000, and no error occurred. Therefore, according to the present embodiment, it has been found that the deep temperature can be measured with extremely high accuracy.

(Third embodiment)
Next, an example of a method for providing the temperature sensor on the substrate 40 will be described. FIG. 23A to FIG. 23E are diagrams for explaining an example of a method of providing a temperature sensor on a base material. Here, the first temperature sensor 50 (for example, composed of a thermocouple element) will be described as an example. The method described below can be similarly applied to the second temperature sensor 52 and the third temperature sensor 55.

  FIG. 23A shows a plan view and a cross-sectional view of the substrate 40 (including the first temperature sensor 50). As shown in the plan view, the base material 40 has a square shape in plan view, and both the vertical Y1 and the horizontal X1 are, for example, 50 mm. Moreover, as shown in the sectional view, the height Y3 of the base material is, for example, 5 mm. The first temperature sensor 50 is embedded in the base material 40. The horizontal X2 of the first temperature sensor 50 is, for example, 0.5 mm, and the vertical (height) Y2 is, for example, 0.5 mm. As the base material 40, for example, foam rubber (for example, natural latex rubber) or foamed resin (for example, foam urethane) can be used.

  FIG. 23B and FIG. 23C show an example of a method of embedding the first temperature sensor 50 in the base material 40. In FIG. 23B, a lateral hole 47a is formed from the side surface of the base material 40 toward the center, and the first temperature sensor 50 is conveyed into the base material 40 through the lateral hole 47a. The sensor 50 is installed at approximately the center of the base material 40.

  In the example of FIG. 23C, a vertical hole 47b is formed instead of the horizontal hole 47a in FIG.

  FIG. 23D and FIG. 23E show another example of a method of embedding the first temperature sensor 50 in the base material 40. In the example of FIGS. 23D and 23E, the base material 40 is divided into a lower portion 40a and an upper portion 40b. When the lower portion 40a and the upper portion 40b are bonded together, the first temperature sensor 50 is sandwiched between both portions 40a and 40b, and as a result, the first temperature sensor 50 is positioned inside the substrate 40. Can be made.

  In the first step of the example of FIG. 23D, the recess 39 is formed in a part of the upper portion 40b of the base material 40. In the second step, the first temperature sensor 50 is embedded in the recess 39 formed in the upper portion 40b of the base material 40, and on the surface of the lower portion 40a of the base material 40 that faces the upper portion 40b. The adhesive material 41 is formed. In the third step, the lower portion 40a and the upper portion 40b of the base material 40 are bonded together. However, since foamed rubber and foamed resin are flexible, the first temperature sensor 50 can be directly sandwiched between the lower portion 40a and the upper portion 40b of the base member 40 without providing the recess 39. An example of this is shown in FIG.

  In the first step of the example of FIG. 23E, no concave portion is formed in the lower portion 40a of the base material 40. In the second step, the adhesive 41 is formed on the surface of the lower portion 40 a of the base material 40 that faces the upper portion 40 b, and the first temperature sensor 50 is placed on the adhesive 41. . In the third step, the lower portion 40a and the upper portion 40b of the base material 40 are bonded together. The base material 40 is made of a soft material. Therefore, at the time of bonding, the central portion of the upper portion 40 b of the base material 40 is deformed so as to wrap the first temperature sensor 50. In addition, the above example is an example and is not limited to these methods.

  As described above, according to at least one embodiment of the present invention, it is possible to measure the deep temperature more accurately. In addition, it is possible to achieve both miniaturization of the temperature measurement unit and high-accuracy measurement.

  Although several embodiments have been described above, it is easily understood by those skilled in the art that many modifications can be made without substantially departing from the novel matters and effects of the present invention. Accordingly, all such modifications are intended to be included in the scope of the present invention. For example, a term described at least once together with a different term having a broader meaning or the same meaning in the specification or the drawings can be replaced with the different term in any part of the specification or the drawings.

4 deep part, 5 surface part, 6 body to be measured (human body, etc.), 7 environment (ambient medium, environmental medium),
8 peeling tape, 9 adhesive layer, 10 affixing structure (adhesive tape),
20a, 20b heat insulating material, 40 base material, 43 temperature measuring unit, 50 first temperature sensor,
52 second temperature sensor, 53 environmental temperature acquisition unit,
54, a third temperature sensor that is a component of the environmental temperature acquisition unit,
55 Air temperature sensor, 100 1st unit, 200 2nd unit

Claims (8)

A temperature measurement unit, an environmental temperature acquisition unit, a calculation unit, and a control unit that controls the operation of the temperature measurement unit and the calculation unit,
The temperature measuring unit is
A substrate as a heat medium having a first surface as a contact surface in contact with a measurement object;
A first temperature sensor that measures the temperature at the first measurement point of the substrate as the first temperature;
A second temperature sensor for measuring a temperature at a second measurement point different from the first measurement point of the substrate as a second temperature;
A heat flow control unit provided on a second surface that is a surface facing the first surface of the substrate and that is the surface on the environment side, and
The environmental temperature acquisition unit acquires the temperature of the environment around the base material as a third temperature,
The first measurement point and the second measurement point are located on the outer surface of the base material or inside the base material,
The heat flow control unit is configured so that the temperature on the second surface of the base material is closer to the third temperature, which is the temperature of the environment, compared to the case where the heat flow control unit is not provided. Heat exchange between
The first temperature sensor and the second temperature sensor measure the first temperature and the second temperature multiple times under the condition that the value of the third temperature is different,
The computing unit is
Based on the first temperature and the second temperature obtained by the plurality of measurements, and the third temperature having the different values corresponding to the plurality of measurements, the object to be separated from the first surface. A temperature measuring device, characterized in that a deep temperature in a deep part of a measuring object is obtained based on an arithmetic expression for the deep temperature. The temperature measuring device according to claim 1,
The temperature measurement device, wherein the heat flow control unit is a material layer made of a material having a thermal conductivity different from that of the base material. The temperature measuring device according to claim 2,
The temperature measurement device, wherein the heat flow control unit includes a temperature control unit that variably controls the temperature of the material layer. The temperature measuring device according to claim 3,
The temperature control device is a Peltier element having a heat absorption surface and a heat dissipation surface, and the heat absorption surface or the heat dissipation surface is in contact with the surface on the environment side of the material layer. The temperature measuring device according to any one of claims 1 to 4,
When the first temperature is represented by a function including the second temperature and the third temperature as variables and including a plurality of constants, the calculation unit may measure the first temperature and the second temperature. And calculating the plurality of constants based on the third temperature, and calculating the depth temperature of the measured object by calculation using the calculation formula of the depth temperature using the calculated plurality of constants. A temperature measuring device. The temperature measuring device according to claim 5,
The first temperature is represented by a first linear function having a first slope and a first intercept, with the second temperature as a variable,
The first intercept of the first linear function is represented by a second linear function having the third temperature as a variable and having a second slope and a second intercept,
The plurality of constants correspond to the first slope, the second slope, and the second intercept,
The first temperature obtained in the first measurement is Tb1, the second temperature is Tp1, the third temperature is Tout1,
The first temperature obtained in the second measurement is Tb2, the second temperature is Tp2, the third temperature is Tout2,
When the first temperature obtained in the third measurement is Tb3, the second temperature is Tp3, and the third temperature is Tout3,
The calculation unit includes the first temperature Tb1, the second temperature Tp1, and the third temperature Tout1 obtained by the first measurement, the first temperature Tb2 obtained by the second measurement, and the second temperature. Based on Tp2 and the third temperature Tout2, and the first temperature Tb3, the second temperature Tp3, and the third temperature Tout3 obtained in the third measurement, the first slope and the second temperature And the value of the second intercept, and the calculation of the deep temperature using the calculated first slope, the second slope, and the value of the second intercept. A temperature measuring device that calculates a deep temperature of the object to be measured by calculation. The temperature measuring device according to claim 6,
The computing unit is
When the first slope is a, the second slope is c, and the second intercept is d,
The values of a, c and d are
Calculated by
The computing unit is
The deep temperature Tc is
The temperature measurement device is calculated by a first calculation formula represented by the first calculation formula as the calculation formula of the deep temperature. The temperature measuring device according to any one of claims 1 to 4,
The first temperature obtained in the first measurement is Tb1, the second temperature is Tp1, the third temperature is Tout1,
When the first temperature obtained in the second measurement is Tb2, the second temperature is Tp2, the third temperature is Tout2, and the value of Tout2 is different from Tout1,
The calculation unit uses the first temperature Tb1 and the second temperature Tp1 obtained by the first measurement, and the first temperature Tb2 and the second temperature Tp2 obtained by the second measurement. , Calculating the deep temperature Tc by performing a calculation according to a second calculation formula as a calculation formula of the deep temperature,
The second calculation formula is:
A temperature measuring device represented by: