JP7393055B2 - Calibration method, calibration program, storage medium and reference sample for thermophysical property measuring equipment - Google Patents

Description

The present invention relates to a calibration method for calibrating a target device, which is a thermophysical property measuring device to be calibrated, against a reference thermophysical property measuring device, a program for executing the calibration method, a storage medium storing the program, and the calibration method. It relates to reference samples used in calibration methods.

Thermophysical properties are physical property values that indicate the ease of heat transfer in a substance, and specifically include thermal conductivity, thermal diffusivity, and thermal effusivity. Thermal conductivity is measured by a steady method or the like. Thermal diffusivity is mainly measured by a periodic heating method or a laser flash method. Furthermore, by measuring the specific heat and density of the sample to be measured, the thermal effusivity can be calculated from the thermal diffusivity and thermal conductivity.

A steady method (JIS A1412-2, ISO 8301) is known as a method for measuring thermal conductivity in the thickness direction of a sample. Further, as methods for measuring thermal diffusivity, a periodic heating method (JIS R7240, Patent Document 1) and a flash method (laser flash method) (JIS R 1611, ISO 18755) are known.

The thermophysical property measuring devices that measure these thermophysical property values are being improved day by day in order to improve the measurement accuracy of each device, and the accuracy and stability of each measurement value is improving.

Japanese Patent Application Publication No. 2011-185852

On the other hand, measurement results obtained by thermophysical property measuring devices have individual differences among a plurality of thermophysical property measuring devices, and even when the same sample is measured, there may be differences in the measurement results. Further, even when determining the same physical property value, for example, thermal diffusivity, there may be a difference in the measurement results between the value determined by the periodic heating method and the value determined by the laser flash method.

As described above, differences in thermophysical property values may occur due to individual differences in measuring devices or differences in measurement methods. In such cases, mutual exchange of measurement results between users of multiple thermophysical property measuring devices or This has the disadvantage that comparative evaluation cannot be performed correctly.

In view of the above-mentioned problems, the present invention aims to improve a method for calibrating thermophysical property measuring devices, etc., and performs calibration so that differences in measurement results do not occur due to individual differences or differences in measurement methods among multiple thermophysical property measuring devices. The purpose is to provide calibration methods, etc.

In order to achieve the above object, the method for calibrating a thermophysical property measuring device according to the first aspect of the present invention uses a reference sample having a reference thermophysical property value at a reference temperature to calibrate a reference device that serves as a reference for the thermophysical property measuring device. This is a method for calibrating a thermophysical property measuring device for calibrating a target device that is a calibration target, the method comprising: adjusting the temperature of the reference sample to the reference temperature; and supplying the reference sample to the target device. a step of measuring a target thermophysical property value, which is a thermophysical property value of the reference sample, using the target device; and a step of measuring a temperature at the time of measurement, which is an ambient temperature of the reference sample, and The method includes the step of calculating a difference between a corrected thermophysical property value at temperature and the target thermophysical property value to obtain a correction value for the target device.

Normally, the target thermophysical property value is measured while keeping the reference sample at the reference temperature, but depending on the state of the target device, the reference sample may not be kept at the reference temperature. In the method for calibrating a thermophysical property measuring device according to the first aspect of the present invention, in the step of measuring the target thermophysical property value, a temperature at the time of measurement, which is the ambient temperature of the reference sample, is measured, and a corrected temperature at the temperature at the time of measurement of the reference sample is measured. A correction value for the target device is obtained by calculating the difference between the physical property value and the target thermophysical property value. Therefore, what is compared with the target thermophysical property value is not the thermophysical property value of the reference sample at the reference temperature, but the thermophysical property value at the measurement temperature, so that the correction value can be calculated accurately. Here, the temperature at the time of measurement, which is the ambient temperature of the reference sample, may be measured before or after the step of measuring the target thermophysical property value.

Next, in the method for calibrating a thermophysical property measuring device according to the second aspect of the present invention, a reference sample having a reference thermophysical property value at a reference temperature is used to perform calibration with respect to a reference device that is a reference for the thermophysical property measuring device. A method for calibrating a thermophysical property measuring device that calibrates a target device, the method comprising: adjusting the temperature of the reference sample to the reference temperature; and mounting the reference sample on the target device. When measuring a target thermophysical property value, which is a thermophysical property value of the reference sample, by the target device, a step of measuring a temperature at the time of measurement, which is an ambient temperature of the reference sample, and a difference between the temperature at the time of measurement and the reference temperature. If there is, the step of measuring the target thermophysical property value by adjusting the temperature so that the reference sample has the reference temperature, and calculating the difference between the target thermophysical property value and the reference thermophysical property value. and determining a correction value for the target device.

According to the method for calibrating a thermophysical property measuring device according to the second aspect of the present invention, when there is a difference between the temperature at the time of measurement and the reference temperature, the temperature is adjusted so that the reference sample has the reference temperature, and the target thermophysical property value is adjusted. Because of the measurement, the correction value can be accurately calculated from the reference thermophysical property value and the target thermophysical property value.

Further, in the method for calibrating a thermophysical property measuring device of the present invention, the step of measuring the target thermophysical property value is performed using a plurality of reference samples having different reference thermophysical property values, and the vertical axis is the target thermophysical property value, The method may include the step of setting a value of a straight line obtained by optimizing the points appearing when the horizontal axis is the reference thermophysical property value using an approximate linear function as the target thermophysical property value. According to this configuration, since a correction value is obtained using a plurality of reference thermophysical property values and a plurality of target thermophysical property values, it is possible to bring the characteristics of the target device closer to the characteristics of the reference device.

In addition, in the method for calibrating a thermophysical property measuring device of the present invention, when the measurement method in the reference device and the measurement method in the target device are different, the thermophysical property values that can be measured for the reference sample by all the different measurement methods are provided. Calibration may be performed using a sample that has According to this configuration, it is possible to accurately calibrate errors in thermophysical property values due to differences in measurement methods.

The method for calibrating a thermophysical property measuring device of the present invention may further include the step of performing noise prevention processing on the target device to reduce at least one of dust, electromagnetic waves, and vibrations. When calibrating the target device, if dust or the like adheres to the target device or the reference sample, there is a risk that errors will occur in the thermophysical property values. Therefore, for example, by attaching a dustproof cover to the target device itself, by attaching a dustproof cover to the reference sample, or by performing noise prevention processing to reduce electromagnetic waves and vibrations, accurate thermophysical property values can be obtained in the target device. can be measured.

Further, a calibration program that can execute the method for calibrating a thermophysical property measuring device according to the first aspect of the present invention uses a reference sample having a reference thermophysical property value at a reference temperature, and uses a reference sample that is a reference for the thermophysical property measuring device. A calibration program capable of executing a method for calibrating a thermophysical property measuring device that calibrates a target device that is a calibration target, the program being executable on the target device, the target device having the reference sample attached thereto. to measure the temperature at the time of measurement, which is the ambient temperature of the reference sample, when measuring the thermophysical property value of the reference sample to measure the target thermophysical property value, and correct the temperature at the time of measurement of the reference sample. The calibration program calculates a difference between a thermophysical property value and the target thermophysical property value to obtain a correction value for the target device, and makes the correction value usable in the target device.

Further, a calibration program that can execute the method for calibrating a thermophysical property measuring device according to the second aspect of the present invention uses a reference sample having a reference thermophysical property value at a reference temperature, and uses a reference sample that is a reference for the thermophysical property measuring device. A calibration program capable of executing a method for calibrating a thermophysical property measuring device that calibrates a target device that is a calibration target, the program being executable on the target device, the target device having the reference sample attached thereto. to measure the temperature at the time of measurement, which is the ambient temperature of the reference sample, when measuring the thermophysical property value of the reference sample to measure the target thermophysical property value, and detect the difference between the temperature at the time of measurement and the reference temperature. If so, adjust the temperature of the reference sample to the reference temperature, measure the target thermophysical property value, calculate the difference between the target thermophysical property value and the reference thermophysical property value, and measure the target thermophysical property value. This is a calibration program that calculates a correction value for and makes the correction value usable in the target device.

The first and second calibration programs may be installed in the target device, server, etc., may be transmitted and received over a network, and may be stored in a storage medium such as a CD ROM, DVD ROM, or flash memory. Good too.

Further, the reference sample used in the method for calibrating the thermophysical property measuring device of the present invention has a point that appears when the vertical axis is the thickness of the reference sample and the horizontal axis is the thermal diffusivity of the reference sample. A material is used that has thermophysical properties such that regions that can be measured by , laser flash method, and periodic heating method overlap with each other. Zirconia ceramic can be used as the material.

According to the reference sample of the present invention, thermophysical property values can be measured using any of the steady method, laser flash method, and periodic heating method. Therefore, in thermophysical property measuring apparatuses that perform measurements using different measuring methods, mutual calibration can be performed.

Furthermore, the reference sample of the present invention can be attached to a thermophysical property measuring device that performs measurements using at least the laser flash method and the periodic heating method, and the thermophysical properties can be measured while being attached to the thermophysical property measuring device. It may be housed in a case equipped with a measurement window. According to this configuration, when performing measurements using at least the laser flash method and the periodic heating method, the measurements can be performed with the reference sample housed in the case.

Further, in the reference sample of the present invention, information including individual identification information of the reference sample may be stored in the case. According to this configuration, since the individual identification information of the reference sample is stored in the case, it is possible to prevent measurement errors when executing the calibration method.

Further, in the reference sample of the present invention, the case may include a positioning section for positioning the reference sample when it is attached to the target device. Some reference samples have different thermophysical property values depending on the direction of the sample, but by providing the positioning section, the reference sample can always be attached to the target device in the correct direction.

FIG. 3 is an explanatory diagram showing a state in which a reference device, a plurality of target devices, and a server are connected to a network. FIG. 2 is an explanatory diagram showing the functional configurations of a reference device and a target device. A graph where the vertical axis is the thickness of the reference sample and the horizontal axis is the thermal diffusivity of the reference sample. An explanatory diagram showing an example of a reference sample and a case. A graph in which the vertical axis is the thermal diffusivity of the target device and the horizontal axis is the thermal diffusivity of the reference device. Explanatory diagram showing a modified example of the case.

Next, with reference to FIGS. 1 to 6, a calibration method, a program, and a reference sample for a thermophysical property measuring device according to an embodiment of the present invention will be described. FIG. 1 shows a state in which a reference device 1 that is a thermophysical property measuring device used in the calibration method of the present invention, target devices 20 (20a to 20d) that are a plurality of calibration targets, and a server 2 are connected to a network 3. FIG. In this embodiment, a program for executing the calibration method of the present invention is stored in the server 2. This program is stored in a storage medium such as a hard disk within the server 2 and can be executed on the server 2 or the target device 20.

Referring to FIG. 1, network 3 includes the Internet, an intranet, a telephone line network, etc., and its format is not particularly limited. One reference device 1 and a plurality of target devices 20 are connected to the network 3. The connection between these devices may be wired or wireless. Further, in this embodiment, a case is described in which the reference device 1 and the target device 20 are connected through the network 3, but each device may not be connected to the network 3 and may be in an independent state.

Referring to FIG. 2, the reference device 1 and target device 20 used in the calibration method of the present invention will be described. In this embodiment, the reference device 1 and the target device 20 are thermophysical property measuring devices having basically the same configuration. Examples of thermophysical property measuring devices include, for example, a thermal diffusivity measuring device that measures thermal diffusivity using a periodic heating method (laser periodic heating method), and a thermal diffusivity measuring device that measures thermal diffusivity using a laser flash method. , or a thermal conductivity measuring device that measures thermal conductivity using a steady method. Here, a thermowave analyzer (manufactured by Bethel Co., Ltd.), which is a thermal diffusivity measurement device that measures thermal diffusivity using a periodic heating method, will be explained as an example.

As shown in FIG. 2, the reference device 1 includes a holder 5 that holds an object to be measured such as a reference sample 4, a heating section 6 that heats the object to be measured, and a thermal sensor 7 that detects the heat of the object to be measured. , a control section 8 that controls the reference device 1. The control unit 8 includes a temperature control unit 9 that controls the temperature of the object to be measured using the heating unit 6, a storage unit 10 that stores various data for controlling the reference device 1, and a signal from the thermal sensor 7. It is equipped with an arithmetic unit 11 that performs arithmetic operations.

In this embodiment, the heating section 6 uses a laser device equipped with a diode laser. The thermal sensor 7 uses infrared thermography, which converts thermal energy radiated from a heated measurement object (reference sample 4, etc.) into temperature, and displays an image as a temperature distribution.

The temperature control section 9 and calculation section 11 in the control section 8 are configured by a computer built into the reference device 1 or connected from the outside, and a program (software) installed in the computer. This computer is composed of a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a hard disk, various interfaces, and the like. The storage unit 10 is composed of storage devices such as RAM, ROM, and hard disk. Note that the server 2 also includes a computer having a CPU, etc., and various communication devices.

The target device 20, like the reference device 1, includes a holder 22, a heating section 23, a thermal sensor 24, a control section 25, a temperature control section 26, a storage section 27, and a calculation section 28. The additional temperature control unit 29 shown in FIG. 2 is a device used during calibration in the calibration method of this embodiment. The additional temperature control unit 29 includes a temperature sensor 30 that detects the temperature of a measurement target attached to the target device 20, and a temperature control unit 31 that controls the temperature around the measurement target. The temperature control unit 31 includes a Peltier cooling element and a heater (not shown), and can control the temperature of the object to be measured by controlling the temperature around the object to be measured.

Further, in this embodiment, the heating section 23, reference sample 4, holder 22, and thermal sensor 24 of the target device 20 are surrounded by a noise prevention panel 32 to perform noise prevention processing. This noise prevention panel 32 has the function of blocking dust and reducing external vibrations and electromagnetic waves.

Next, the reference sample 4 and the reference sample case 40 used in the method for calibrating a thermophysical property measuring device of this embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a graph in which the thickness of the reference sample 4 is plotted on the vertical axis and the thermal diffusivity of the reference sample 4 is plotted on the horizontal axis. FIG. 4 is an explanatory diagram showing the reference sample 4 and a case 40 surrounding the reference sample 4.

Reference sample 4 is a sample having reference thermophysical property values at reference temperature. For example, it is a member whose thermal diffusivity is 1000 mm ² /s at a reference temperature of 25°C. In this embodiment, the reference sample 4 is formed into a square shape when viewed from above, and has a thickness of 30 μm.

In addition, in this embodiment, the reference sample 4 is measured by the steady method, which is expressed in a graph where the vertical axis is the thickness of the reference sample 4 and the horizontal axis is the thermal diffusivity of the reference sample 4, as shown in FIG. A material is used that matches the region where the measurable region A, the measurable region B of the laser flash method, and the measurable region C of the periodic heating method overlap each other (symbol D in FIG. 3). In this embodiment, zirconia ceramic is used as the material for the reference sample 4.

The case 40 that protects the reference sample 4 is a case that can be attached to various thermophysical property measuring devices. In this embodiment, as shown in FIG. 4, the case 40 includes a guard part 41 formed in a lattice shape from a metal wire, and a spacer 42 that holds the guard part 41 and abuts against the reference sample 4. ing. Since the case 40 of this embodiment has the above-mentioned configuration, the measurement window 43 is capable of measuring areas other than the wire rod, and the reference sample 4 can be heated entirely by the heating unit 23. .

Furthermore, in this embodiment, the spacer 42 is provided with a storage section 44 . This storage unit 44 stores information including individual identification information of the reference sample 4, which is the measurement target object held therein. In this embodiment, when the case 40 houses the reference sample 4 and is attached to the holder 22 of the target device 20, the reference sample 4 is connected to the interface (not shown) provided in the holder 22, and the reference sample 4 is attached to the target device 20. 4 individual identification information can be read. The individual identification information of the reference sample 4 includes the material of the reference sample, the thermophysical property value at the reference temperature, and the like.

Next, a method for measuring thermophysical properties in the target device 20 before calibration will be described. When the target device 20 is used in a normal state, the additional temperature control unit 29 shown in FIG. 2 is not attached to the target device 20.

In this state, when measuring the thermophysical property values of the reference sample 4 using the target device 20, the temperature of the reference sample 4 is first adjusted to the reference temperature of 25°C. Next, this reference sample 4 is attached to the holder 22 of the target device 20. Next, the reference sample 4 is heated by the heating unit 23, the thermal signal detected by the thermal sensor 24 is calculated by the calculation unit 28, and the thermal diffusivity is calculated and measured. The specific measurement of thermal diffusivity is described in Patent Document 1, the instruction manual of the device, etc., and is well known, so a detailed explanation will be omitted here.

Here, if there is an individual difference between the reference device 1 and the target device 20, a difference will occur between the value of the thermal diffusivity measured by the reference device 1 and the value of the thermal diffusivity measured by the target device 20. .

Next, a method for calibrating the thermophysical property measuring device according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 6. In the calibration method of the first embodiment, the difference in thermal diffusivity values caused by individual differences between the reference device 1 and the target device 20 is corrected, and the individual differences between the reference device 1 and the target device 20 are eliminated. Calibration is performed so that the target thermophysical property value, which is the measurement result measured by the target device 20, is the same as the reference thermophysical property value measured by the reference device 1.

The calibration method according to the first embodiment of the present invention is mainly executed by a calibration program installed on the server 2, and is performed in the following steps. First, the temperature of the reference sample 4 is adjusted to the reference temperature of 25° C. (STEP 1). Specifically, the reference sample 4 is housed in the case 40 and kept at the reference temperature using a constant temperature device or the like.

Next, the operator who performs the calibration attaches the reference sample 4 to the target device 20 (STEP 2). In this embodiment, since the measuring instrument measures thermophysical properties using a periodic heating method, the reference sample 4 is attached to the holder 22 while being housed in the case 40 . At this time, the individual identification information of the reference sample 4 stored in the storage unit 44 provided in the case 40 is read into the target device 20.

Next, the operator surrounds the heating unit 23, reference sample 4, holder 22, and thermal sensor 24 of the target device 20 with a noise prevention panel 32, and performs noise prevention processing (STEP 3). This noise prevention process may be performed by surrounding the entire outside of the target device 20 with a noise prevention panel (not shown).

Next, the calibration program of the present invention operates the target device 20 to measure the target thermophysical property value, which is the thermophysical property value of the reference sample 4 (STEP 4). Specifically, the temperature control section 26 activates the diode laser of the heating section 23 to heat the reference sample 4, and the thermal sensor 24 detects thermal energy on the back surface of the reference sample 4. The calculated thermal signal is calculated by the calculation unit 28, and the target thermophysical property value (thermal diffusivity) is calculated and measured.

At this time, the temperature sensor 30 of the additional temperature control section 29 measures the measurement temperature, which is the ambient temperature of the reference sample 4 (STEP 5). In this embodiment, the temperature of the holder 22 is measured as the ambient temperature at the time of measurement. Examples of this ambient temperature include the ambient temperature of the reference sample 4, the temperature of the case 40, and the temperature of other members and spaces around the reference sample 4.

If the temperature at the time of measurement is different from the reference temperature, the thermophysical property value of the reference sample 4 will be different from the reference thermophysical property value at the reference temperature. Here, in the calibration program of the present invention, a corrected thermophysical property value, which is a thermophysical property value of the reference sample 4 at the temperature at the time of measurement, is read out. This corrected thermophysical property value is stored in the server 2 or in the storage unit 44 of the case 40, or is read from a data table of temperature and thermophysical property values measured by the reference device 1. This corrected thermophysical property value may be loaded into the storage unit 27 and used.

Next, the calibration program of the present invention calculates the difference between the target thermophysical property value and the corrected thermophysical property value to obtain a correction value for the target device 20 (STEP 6). The target thermophysical property value is the thermophysical property value at the temperature at the time of measurement, and the corrected thermophysical property value is also the thermophysical property value of the reference sample 4 at the same temperature as the temperature at the time of measurement. Therefore, by calculating the difference between the target thermophysical property value and the corrected thermophysical property value, calculating a correction value (or function) that eliminates this difference, and making it usable in the target device 20, it is possible to accurately target the target thermophysical property value. Calibration of device 20 can be performed.

For example, if the target thermophysical property value is 10% minus the corrected thermophysical property value, a numerical value (or function) to correct this minus 10% value to the same value as the reference thermophysical property value. is the correction value. In this way, by the above calibration method, the target device 20 becomes a device having the same characteristics as the reference device 1. Therefore, even if there are multiple target devices 20 (20a to 20d in FIG. 1), there will be no error in the measured data between the target devices 20a to 20d, making it easy to share and compare the measured data. Become.

Next, a calibration method according to a second embodiment of the present invention will be described. The calibration method of the second embodiment is different from the first embodiment in that, when the temperature at the time of measurement and the reference temperature are different, the temperature of the reference sample 4 is controlled so that the temperature at the time of measurement is the same as the reference temperature. It's different.

In the calibration method of the second embodiment, as in the first embodiment, the temperature of the reference sample 4 is adjusted to the reference temperature of 25° C. (STEP 1), and the reference sample is placed in the target device 20. 4 (STEP 2), performs noise prevention processing (STEP 3), operates the target device 20 to measure the target thermophysical property value, which is the thermophysical property value of the reference sample 4 (STEP 4), and performs additional temperature control. The temperature at the time of measurement, which is the ambient temperature of the reference sample 4, is measured by the temperature sensor 30 of the section 29 (STEP 5).

In the calibration method of the second embodiment, if the temperature at the time of measurement is different from the reference temperature, control is performed so that the temperature at the time of measurement is the same as the reference temperature (STEP 7). Specifically, when the temperature at the time of measurement is lower than the reference temperature, the temperature control section 31 warms the area around the reference sample 4 so that the temperature around the reference sample 4 reaches the reference temperature of 25°C. Control. Conversely, if the temperature of the reference sample 4 at the time of measurement is higher than the reference temperature, the temperature control section 31 cools the area around the reference sample 4.

After the temperature detected by the temperature sensor 30 becomes the same as the reference temperature and stabilizes in STEP 7, the calibration program calculates the difference between the target thermophysical property value and the reference thermophysical property value, and Find a correction value for (STEP 8). In this case, since both the target thermophysical property value and the reference thermophysical property value are thermophysical property values at the reference temperature, the difference between the two becomes the individual difference between the reference device 1 and the target device 20.

The calibration program determines a correction value that makes the target thermophysical property value the same as the reference thermophysical property value, and stores this correction value in the storage unit 27. This allows the correction value to be used by the target device 20. For example, if the target thermophysical property value is 10% minus the reference thermophysical property value, a numerical value (or function) to correct this minus 10% value to the same value as the reference thermophysical property value. is the correction value.

Further, according to the calibration methods of the first and second embodiments, even if the measurement methods of the reference device 1 and the target device 20 are different, the reference sample 4 is compatible with any of the different measurement methods. Since this is possible, calibration can be performed in the target device 20 of each measurement method in the same manner as in the above embodiment.

In addition, in the calibration methods of the first and second embodiments, the amount of heating energy of the heating unit 23 of the target device 20 and the amount of heating energy of the heating unit 6 of the reference device 1 are compared, and if there is a difference between the two, , the amount of heating energy of the heating unit 23 of the target device 20 may be controlled in the same way as the reference device 1. Thereby, the temperature change characteristics of the reference sample 4 during calibration can be controlled in the same manner as the reference device 1, and the individual differences between the reference device 1 and the target device 20 can be further reduced.

Furthermore, in the calibration method of each of the embodiments described above, the step of obtaining the correction value may be performed multiple times, and the obtained correction values may be averaged. This makes it possible to obtain more accurate correction values.

At this time, an appropriate range may be determined in advance for the obtained target thermophysical property value or correction value, and when a value exceeding this appropriate range is detected, that value may be removed as noise. When measuring with a thermophysical property measuring device, inappropriate values may be obtained due to disturbance factors, but by setting the appropriate range for each value in this way, it is possible to eliminate noise caused by external factors. can.

Next, the case where the calibration method of each of the above embodiments is performed using a plurality of reference samples 4 having different reference thermophysical property values will be described. For example, the material of the reference sample 4 is a graphite sheet, and three reference samples 4 having reference thermophysical property values of thermal diffusivities of 800, 900, and 1000 mm ² /s, respectively, are used.

The target thermophysical property values are determined using these three reference samples 4, and the vertical axis is the target thermophysical property value (thermal diffusivity determined by the target device 20), and the horizontal axis is the reference thermophysical property value (the thermal diffusivity determined by the target device 1). When expressed in a graph as the thermal diffusivity (thermal diffusivity determined by Here, when a straight line optimized by an approximate straight line function is drawn using the three points appearing in FIG. 5, a straight line with symbol L is obtained. By deriving the target thermophysical property value from the value of the straight line represented by the symbol L, the characteristics of the target device 20 can be brought closer to the characteristics of the reference device 1. Note that the optimization using the approximate linear function can be performed by a well-known method such as linear regression using the least squares method.

By implementing the calibration method of the above embodiment on a plurality of target devices 20a to 20d shown in FIG. 1, data such as correction values for each target device 20 can be stored in the server 2. Further, the calibration method of the embodiment described above can be periodically performed on each of the target devices 20a to 20d. By periodically performing the calibration method in this way, the administrator can also grasp changes in the characteristics of each of the target devices 20a to 20d over time. Therefore, in the event that a failure is likely to occur in any one of the target devices 20a to 20d, repairs or other measures can be taken in advance.

Next, a modification of the case 40 will be described with reference to FIG. 6. As shown in FIG. 6, the case 45 has a metal body that covers almost the entire surface of the reference sample 4, and has a shape in which a circular measurement window 46 is provided in a part of the center. Although FIG. 6 shows the front surface of the case 45, a measurement window 46 is similarly formed on the back surface.

When the thermophysical property measuring device performs measurements using a periodic heating method, the heating point and measurement point of the reference sample 4 are points, so a case having such a shape is suitable for protecting the reference sample 4. Further, a two-dimensional code 47 in which individual identification information of the reference sample 4 is recorded may be provided on the surface of the case 45. Furthermore, individual identification information may be acquired wirelessly using an RFID tag or the like.

Further, as shown in FIG. 6, the case 45 is provided with a positioning recess 48 (positioning part) that positions the case 45 with respect to the holder 22, corresponding to a positioning protrusion (not shown) provided on the holder 22 of the target device 20. It's okay. When the object to be measured for thermophysical properties is a material such as a graphite sheet, the properties often differ between the longitudinal and lateral directions of the sample. In such a case, when mounting the reference sample 4 on the holder 22, it is necessary to always keep the length and width of the reference sample 4 constant.

In this embodiment, by providing such a positioning recess 48 in the case 45, the reference sample 4 can always be attached to the holder 22 in the correct direction. Therefore, it is particularly suitable for a thermophysical property measuring device that measures thermophysical property values using a periodic heating method. This positioning recess 48 may be a protrusion, and in the case of the case 40 in FIG. 4, the guard portion 41 may be used for positioning.

Although the calibration program in each of the above embodiments is installed in the server 2, the present invention is not limited to this, and the calibration program may be stored in a storage medium such as a flash memory and installed directly in the target device 20 to be calibrated. good. Further, in each of the above embodiments, noise prevention processing is performed, but if the target device 20 is installed in an environment where dust and the like are not a problem, such as a clean room, noise prevention processing is not necessary.

DESCRIPTION OF SYMBOLS 1... Reference device, 2... Server, 3... Network, 4... Reference sample, 5... Holder, 6... Heating part, 7... Thermal sensor, 8... Control part, 9... Temperature control part, 10... Storage part, 11... Arithmetic unit, 20... Target device, 22... Holder, 23... Heating unit, 24... Heat sensor, 25... Control unit, 26... Temperature control unit, 27... Storage unit, 28... Arithmetic unit, 29... Additional temperature control unit, 30...Temperature sensor, 31...Temperature control section, 32...Noise prevention panel, 40...Case, 41...Guard section, 42...Spacer, 43...Measurement window, 44...Storage section, 45...Case, 46...Measurement window, 47 ...Two-dimensional code, 48...Positioning recess.

Claims (13)

A method for calibrating a thermophysical property measuring device, in which a target device to be calibrated is calibrated with respect to a reference device serving as a reference for the thermophysical property measuring device, using a reference sample having a reference thermophysical property value at a reference temperature, the method comprising:
adjusting the temperature of the reference sample to the reference temperature;
mounting the reference sample on the target device;
measuring a target thermophysical property value that is a thermophysical property value of the reference sample using the target device;
A temperature at the time of measurement, which is an ambient temperature of the reference sample, is measured, and a difference between a corrected thermophysical property value of the reference sample at the temperature at the time of measurement and the target thermophysical property value is calculated to obtain a correction value for the target device. A method for calibrating a thermophysical property measuring device, comprising the steps of: A method for calibrating a thermophysical property measuring device, in which a target device to be calibrated is calibrated with respect to a reference device serving as a reference for the thermophysical property measuring device, using a reference sample having a reference thermophysical property value at a reference temperature, the method comprising:
adjusting the temperature of the reference sample to the reference temperature;
mounting the reference sample on the target device;
when measuring a target thermophysical property value, which is a thermophysical property value of the reference sample, with the target device, measuring a temperature at the time of measurement, which is an ambient temperature of the reference sample;
If there is a difference between the temperature at the time of measurement and the reference temperature, adjusting the temperature so that the reference sample reaches the reference temperature and measuring the target thermophysical property value;
A method for calibrating a thermophysical property measuring device, comprising the step of calculating a difference between the target thermophysical property value and the reference thermophysical property value to obtain a correction value for the target device. A method for calibrating a thermophysical property measuring device according to claim 1 or 2, comprising:
performing the step of measuring the target thermophysical property value with a plurality of reference samples having different reference thermophysical property values;
A thermophysical property measuring device comprising the step of setting the value of a straight line obtained by optimizing the points appearing when the vertical axis is the target thermophysical property value and the horizontal axis is the reference thermophysical property value as the target thermophysical property value. Calibration method. A method for calibrating a thermophysical property measuring device according to any one of claims 1 to 3, comprising:
When the measurement method in the reference device and the measurement method in the target device are different,
A method for calibrating a thermophysical property measuring device, in which the reference sample is calibrated using a sample having thermophysical property values that can be measured by all different measurement methods. A method for calibrating a thermophysical property measuring device according to any one of claims 1 to 4, comprising:
A method for calibrating a thermophysical property measuring device, further comprising the step of performing noise prevention processing on the target device to reduce at least one of dust, electromagnetic waves, and vibrations. A method for calibrating a thermophysical property measuring device that calibrates a target device to be calibrated can be executed against a reference device that is a reference for the thermophysical property measuring device using a reference sample having a reference thermophysical property value at a reference temperature. A calibration program,
executable on the target device;
Activating the target device to which the reference sample is attached, and measuring the temperature at the time of measurement, which is the ambient temperature of the reference sample when measuring the thermophysical property value of the reference sample and measuring the target thermophysical property value;
A calibration program that calculates a difference between a corrected thermophysical property value of the reference sample at the measurement temperature and the target thermophysical property value to obtain a correction value in the target device, and makes the correction value usable in the target device. . A method for calibrating a thermophysical property measuring device that calibrates a target device to be calibrated can be executed against a reference device that is a reference for the thermophysical property measuring device using a reference sample having a reference thermophysical property value at a reference temperature. A calibration program,
executable on the target device;
Activating the target device to which the reference sample is attached, and measuring the temperature at the time of measurement, which is the ambient temperature of the reference sample when measuring the thermophysical property value of the reference sample and measuring the target thermophysical property value;
If there is a difference between the temperature at the time of measurement and the reference temperature, adjusting the temperature so that the reference sample reaches the reference temperature and measuring the target thermophysical property value;
A calibration program that calculates a difference between the target thermophysical property value and the reference thermophysical property value to obtain a correction value for the target device, and makes the correction value usable in the target device. A storage medium storing the calibration program according to claim 6 or 7. A reference sample used in the method for calibrating a thermophysical property measuring device according to any one of claims 1 to 5,
When the vertical axis is the thickness of the reference sample and the horizontal axis is the thermal diffusivity of the reference sample, the point that appears is the area where the areas measurable by the steady method, laser flash method, and periodic heating method overlap with each other. A reference sample that is a material with thermophysical properties. The reference sample according to claim 9, wherein the material is zirconia ceramic. The reference sample according to any one of claims 9 or 10,
It can be attached to a thermophysical property measuring device that performs measurements using at least the laser flash method and the periodic heating method, and is housed in a case equipped with a measurement window that allows measurement of thermophysical properties while being attached to the thermophysical property measuring device. Standard sample. The reference sample according to claim 11, wherein information including individual identification information of the reference sample is stored in the case. The reference sample according to claim 11 or 12, wherein the case includes a positioning section that performs positioning when the case is mounted on the target device.

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