JP2005345333A - Thermal analyzer and thermal analysis method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal analyzer capable of always placing a sample container on a heat-sensitive plate at a constant position, and to provide a thermal analysis method. <P>SOLUTION: The thermal analyzer has the heat-sensitive plate 16 on which the sample container 24 is placed and a fixture 41 equipped with a pair of holes 43 capable of permitting the insertion of the sample container 24 and the positioning of the sample container 24. In this thermal analyzer, the fixture 41 is detachably supported on the heat-sensitive plate 16 at a predetermined position by a cylindrical partition wall 8 being a guide member. The sample container 24 which houses a measuring sample 22 and the sample container 24 which houses a reference substance 23 are respectively inserted in a pair of the holes 43 to be placed on the heat-sensitive plate 16 at a predetermined position. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a thermal analyzer that measures the thermal characteristics of a sample while the sample is placed on a heat sensitive plate. The present invention also relates to a thermal analysis method performed using the thermal analysis apparatus.

  It has been well known that thermal analyzers include DTA (Differential Thermal Analysis) devices, DSC (Differential Scanning Calorimeter) devices, and the like. DTA is a measurement method for measuring a temperature difference generated between a measurement sample and a reference material as a function of temperature or time while changing the temperatures of the measurement sample and the reference material according to a predetermined program. DSC is a measurement method for measuring a difference in energy input between a measurement sample and a reference material as a function of temperature or time while changing the temperatures of the measurement sample and the reference material according to a predetermined program.

  As for DSC, two types of heat compensation type DSC and heat flux type DSC are known due to the difference in measurement method. The thermal compensation type DSC may also be referred to as an input compensation type DSC. A heat flux DSC may also be referred to as a quantitative DTA.

  In the thermal compensation type DSC, the temperature of the measurement sample and the reference material is changed according to a predetermined program, and the temperature difference between the measurement sample and the reference material generated at that time becomes 0 (zero). Is supplied with heat or energy and the energy is measured against temperature or time. On the other hand, in the heat flux type DSC, the surface temperature of the measurement sample and the reference material is measured, and the difference in the heat flux between the measurement sample and the reference material is obtained based on the temperature difference between the surface temperatures.

  Between the heat compensation type DSC and the heat flux type DSC, the heat compensation type DSC directly measures the amount of heat, whereas the heat flux type DSC is based on the surface temperature difference generated between the measurement sample and the reference material. There is a difference in that the amount of heat is indirectly measured. In addition, between a general DTA and a heat flux type DSC (that is, a quantitative DTA), a general DTA inserts a temperature measuring point of a temperature measuring device such as a thermocouple into the sample or the like, and the internal temperature of the sample or the like. However, the quantitative DTA is different in that the surface temperature of the sample or the like is measured by placing a temperature measuring point outside the sample or the like.

  As an apparatus for performing the DSC as described above, for example, a sample chamber was formed and heated and heated to increase the temperature, and a heat sensitive plate disposed in the sample chamber and receiving heat from the partition to increase the temperature. A thermal analyzer is known (see, for example, Patent Document 1). In this apparatus, a sample container containing a measurement sample and a reference material is placed on the heat sensitive plate and heated. And the temperature dependence of a measurement sample is measured based on the temperature difference which arises between a measurement sample and a reference material.

JP-A-8-247777 (4th page, FIG. 6)

  In the measurement of DSC or the like that is widely performed in general, a sample container is placed at a predetermined position on a heat sensitive plate that a measurer recognizes to be approximately the same by visual observation, and measurement is performed on the sample container. However, in some cases, it may be desired to perform measurement in a state where the sample container is accurately placed at a predetermined position on the heat sensitive plate. For example, the case where specific heat measurement is performed or the case where a quality control department checks the quality of many substances of the same type is considered as such a case.

  Here, the specific heat measurement is the following measurement. That is, first, three types of sample containers are prepared: an empty sample container, a sample container containing a substance whose specific heat capacity is known, and a sample container containing a sample whose specific heat is to be measured. Then, each of these sample containers is individually placed on a heat sensitive plate such as a DSC apparatus, and the change in the amount of heat is measured. That is, the measurement is performed three times in total for each of the three types of sample containers. And the specific heat of a sample is calculated | required based on the result obtained by these three measurements. In order to obtain highly reproducible results in such specific heat measurement, when placing the above three types of sample containers individually on the heat sensitive plate, the sample containers are accurately placed at the same position on the heat sensitive plate. There is a need.

  In addition, when performing quality checks using a DSC or the like in the quality control department, in order to increase the reliability of quality control, measurements should be made after accurately placing a large number of samples on the same position on the thermal plate. is required.

  However, in the conventional thermal analysis apparatus, when the sample container is placed on the heat sensitive plate, the placement position is confirmed by visual observation, so there is a possibility that the position where the sample container is placed may be displaced. It was. When such a position shift occurs, the reproducibility of the measurement result may be deteriorated.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a thermal analysis apparatus and a thermal analysis method capable of always placing a sample container on a certain position on a heat sensitive plate.

  In order to achieve the above object, a thermal analysis apparatus according to the present invention includes a thermal plate on which a sample container is placed, a jig having a hole into which the sample container can be inserted and the sample container can be positioned. And a guide member that removably supports the jig at a predetermined position with respect to the heat sensitive plate. Here, the above-mentioned hole for inserting the sample container is a size that allows the sample container to be taken in and out, and is larger than the sample container to such an extent that the variation in the reproducibility of the result of the thermal analysis measurement falls within an allowable range. It is a hole. Specifically, it can be a circular hole, a square hole, or the like that is about 0.5 mm to 1.0 mm larger than the outer peripheral surface of the sample container.

  According to the thermal analysis apparatus having the above configuration, the jig that supports the sample container is supported at a predetermined position with respect to the heat sensitive plate of the thermal analysis apparatus by the guide member. If the sample container is inserted into the hole provided in the jig, the sample container can be accurately placed at a predetermined position on the heat sensitive plate of the thermal analyzer. As a result, the reproducibility of the measurement result can be maintained high in the measurement using the thermal analyzer.

  In the thermal analysis apparatus according to the present invention, it is preferable that the thermal analysis apparatus further includes a partition that forms a sample chamber in which the thermal plate is disposed, and the guide member is the partition. In this thermal analyzer, the sample chamber is a space formed by partition walls, and is a place where measurement is actually performed. In the thermal analyzer, a sample is placed on a heat sensitive plate disposed in a sample chamber, and the partition is heated by a heater such as an electric furnace. By doing so, heat is transferred to the sample through the heat sensitive plate in the sample chamber.

  In order to improve the heat transfer to the heat sensitive plate, the partition walls are preferably formed of a material having high thermal conductivity, such as silver. As described above, the partition wall made of a material having high thermal conductivity functions as a heat sink, that is, a heat reservoir, which is an element for absorbing and further dissipating heat. If this partition is used as a guide member, it is not necessary to newly install a guide member, so that the structure of the thermal analyzer can be simplified.

  In the thermal analysis apparatus according to the present invention, it is desirable that the jig has an outer peripheral surface that is fitted to an inner peripheral surface of the guide member. The term “fitting” as used herein refers to a state in which a jig is inserted into the guide member and is in a fitting relationship with no backlash. If the outer peripheral surface of the jig is fitted to the inner peripheral surface of the guide member, the jig can be accurately supported at a predetermined position with respect to the heat sensitive plate.

  In the thermal analysis apparatus according to the present invention, it is preferable that the thermal plate further has a gas hole for allowing gas to pass therethrough, and the jig has a hole for measuring a position with respect to the gas hole. In measurement using a thermal analyzer, an inert gas may be introduced into the sample chamber to replace the gas in the sample chamber, thereby inactivating the sample. In such a case, if a gas hole is provided in the heat sensitive plate, gas can be introduced into the sample chamber through the gas hole.

  In addition, if the jig is provided with a position measurement hole for measuring the position with respect to the gas hole, when the sample container is placed on the thermal plate, the position measurement hole of the jig and the gas hole of the thermal plate By aligning these positions, the jig can be more accurately placed at a predetermined position with respect to the heat sensitive plate. Therefore, the sample container inserted into the hole of the jig can be more accurately placed at a predetermined position with respect to the heat sensitive plate.

  In the thermal analysis apparatus according to the present invention, the thermal analysis apparatus further includes a soaking block protruding above the sample container mounting surface of the thermosensitive plate, and the jig is provided in the soaking block in a portion protruding from the thermosensitive plate. It is desirable to have a stepped portion that fits. In this case, the jig and the soaking block may be loosely fitted. By fitting the stepped portion of the jig into the soaking block, the approximate position of the jig relative to the heat sensitive plate can be determined.

  Next, the thermal analysis method according to the present invention is a thermal analysis method in which measurement is performed in a state where a sample container containing a sample is placed on a heat sensitive plate, and the sample container can be inserted and the sample container can be positioned. A jig provided with a hole is placed at a predetermined position with respect to the heat sensitive plate, the sample container is placed on the heat sensitive plate through the hole, and the jig is removed from the heat sensitive plate while the sample container is placed on the heat sensitive plate. It is characterized by removing. According to this thermal analysis method, since the sample container is accurately placed at a predetermined position on the heat sensitive plate using a jig, it is possible to maintain high reproducibility of the measurement result in the measurement using the thermal analysis apparatus. .

  According to the thermal analysis apparatus of the present invention, when the sample container is placed on the heat sensitive plate, the jig is supported at a predetermined position with respect to the heat sensitive plate using the guide member, and the sample container is placed in the hole provided in the jig. Inserted. Thereby, a sample container can be correctly mounted in a predetermined position with respect to the heat sensitive plate of a thermal analyzer. As a result, the reproducibility of the measurement result can be maintained high.

  Hereinafter, a case where the thermal analysis apparatus and the thermal analysis method according to the present invention are applied to a heat flux type DSC apparatus and a thermal analysis method using the same will be described as an example. Of course, the present invention is not limited to this embodiment.

  FIG. 1 shows a main part of an embodiment of a thermal analysis apparatus according to the present invention. FIG. 2 shows a DSC device that is part of one embodiment of the thermal analyzer. FIG. 3 shows a jig that is another part of one embodiment of the thermal analyzer. In FIG. 2, the DSC device 40 includes a base block 2 fixed on the upper surface of the housing table 1, a measurement unit 3 fixed on the base block 2, and a heat insulating case 4 that covers the entire measurement unit 3. And have. The heat insulating case 4 is formed in a substantially cylindrical shape, and is formed by evenly filling a cotton-like heat insulating material 10 between the outer frame 5 and the inner frame 6. The heat insulation case 4 is detachably mounted on the upper surface of the base block 2.

  As shown in FIG. 1, the measurement unit 3 includes a cylindrical partition wall 8 around which a heater wire 7 is wound, and a cylindrical cover 9 that covers the outer periphery of the partition wall 8. The partition wall 8 and the cover 9 are fixed to each other by welding or the like at their upper end portions. A sample chamber R that is a cylindrical space is formed inside the partition wall 8, and the bottom wall 8 a of the partition wall 8 is the bottom of the sample chamber R. The partition wall 8 is formed of a material having high thermal conductivity, such as silver, and functions as a heat sink for stably maintaining the temperature in the sample chamber R. Similarly, the cover 9 is formed of a material having high thermal conductivity.

  On the bottom surface of the sample chamber R, that is, the top surface of the bottom wall 8a of the partition wall 8, a table 15 is disposed so as to be in contact with or close to the side wall of the partition wall 8. As shown in FIG. 3, the table 15 is formed as a circular block having a diameter substantially equal to the inner diameter of the sample chamber R, and an elongated hole 11 for inserting an insulator tube and a gas tube at the center thereof. Further, four through holes 14 for inserting set screws 13 are opened at appropriate positions on the outer peripheral edge side.

  A heat sensitive plate 16 is placed on the table 15. A sample placement portion 16 a that rises upward is formed in the approximate center of the heat sensitive plate 16. Two soaking blocks 17 are placed on the heat sensitive plate 16 at positions facing each other across the sample placement portion 16a. The soaking block 17, the heat sensitive plate 16 and the base 15 are fastened and fixed to the bottom wall 8a of the partition wall 8 by a set screw 13 (see FIG. 1). The soaking block 17 is formed of a material having high thermal conductivity, such as silver, and is formed in a partial disk shape having an arc-shaped side surface. The soaking block 17 is provided with a through hole 20 for inserting the set screw 13. The arc shape of the arc-shaped side surface of the soaking block 17 matches the arc surface of the inner peripheral side surface of the sample chamber R.

  The heat sensitive plate 16 is formed of a material having a high thermal conductivity, such as platinum, a platinum rhodium alloy, or the like, or a material having a high electromotive force, such as constantan, and has a generally circular shape as shown in FIG. The outer diameter of the heat sensitive plate 16 is set substantially equal to the inner diameter of the sample chamber R. The heat sensitive plate 16 is configured to have the above-described sample mounting portion 16a that protrudes above the fixing portion 16b and the fixing portion 16b by being bent.

  Note that the bent shapes of the sample mounting portion 16a and the fixing portion 16b are not limited to bending, and can be formed by cutting or other arbitrary processing. A through hole 18 for inserting a set screw 13 is formed in each fixing portion 16 b of the heat sensitive plate 16. The sample placement unit 16a is provided with regions Fa and Fb for placing the measurement sample and the reference material. Further, two gas holes 19a and 19b for allowing the gas filled in the sample chamber R to pass are opened between the two regions.

  In FIG. 2, a silver lid 21 is detachably mounted on the upper end of the partition wall 8 so that the sample chamber R is hermetically shielded from the outside. FIG. 4 shows the inside of the sample chamber R with the lid 21 removed. As shown in FIG. 4, the measurement sample 22 and the reference material 23 are placed on the sample placement portion 16 a of the thermal plate 16 in a state of being accommodated in the sample container 24.

  Returning to FIG. 2, an insulator tube 25 is provided at the center of the bottom wall 8 a of the partition wall 8, and a thermocouple bundle 26 is inserted into the insulator tube 25. The thermocouple bundle 26 is constituted by four thermocouple wires as shown in FIG. 5, and the temperature measuring points S1 and S2 of the pair of thermocouples are heat sensitive at positions corresponding to the measurement sample 22 and the reference sample 23, respectively. For example, it is fixed to the lower surface of the plate 16 by spot welding. These thermocouple bundles 26 are led to a temperature difference measuring circuit 29. The output of the temperature difference measuring circuit 29 is guided to a calorific value calculating circuit 30, and the output result of the calorific value calculating circuit 30 is displayed on a video display device 31 such as a CRT or hard-copied by a printer 32.

  Returning to FIG. 2, another insulator tube 27 is provided on the right side surface of the partition wall 8, and a pair of thermocouple wires 28 are inserted into the insulator tube 27. The temperature measuring point S3 of the thermocouple wire 28 is set at an appropriate position on the partition wall 8, particularly the bottom wall 8a, as shown in FIG. The output terminal side of the thermocouple wire 28 is led to the temperature measurement circuit 33, and the output of the temperature measurement circuit 33 is sent to the heater temperature control circuit 34. The output signal of the heater temperature control circuit 34 controls the amount of current supplied to the power supply circuit 37 based on the sent signal. As shown in FIG. 2, the power supply line 35 from the power supply circuit 37 is connected to the heater wire 7 through a tube 36 provided on the left side surface of the partition wall 8.

  A gas pipe 38 is disposed on the right side of the thermocouple insulator pipe 25. The upper end of the gas pipe 38 is fitted into the bottom wall 8 a of the partition wall 8, and the lower end thereof is connected to a gas introduction terminal 39 provided on the right side surface of the base block 2.

  The jig 41 shown in FIG. 3 is shown in a plan view in FIG. 6A and a cross-sectional view in FIG. FIG. 6A is a plan view according to the arrow B in FIG. FIG. 6B is a cross-sectional view taken along the line AA in FIG.

  As shown in these drawings, the jig 41 is formed in a substantially cylindrical shape and includes a flange 41a, a fitting part 41b, and a step part 41c. The outer peripheries of the flange 41a and the fitting part 41b are circular. An opening Q that opens upward is provided at the upper end of the jig 41. As shown in FIG. 6B, the inside of the jig 41 is a space. Further, the thickness T0 of the bottom wall of the stepped portion 41c is smaller than the height Lh of the sample container 24 (see FIG. 3). In FIG. 1, the outer diameter φ0 of the fitting portion 41b is formed to be slightly smaller than the inner diameter φ1 of the partition wall 8, whereby the fitting portion 41b is loosely fitted to the inner peripheral surface of the partition wall 8.

  Here, “loosely fitting” means that when a person picks up the flange 41a to carry the jig 41 to the position just above the sample chamber R and releases the jig from the position to drop the jig 41, the jig 41 is moved. Is so large that it falls to the bottom of the partition wall 8 due to its own weight. However, when the fitting portion 41b fits inside the partition wall 8, there is a large backlash between the jig 41 and the partition wall 8. This is a state in which the dimensional difference is small to the extent that no occurrence occurs.

  As shown in FIG. 3, the outer shape of the stepped portion 41 c provided at the lower portion of the jig 41 is a substantially rectangular shape centered on the diameter of the fitting portion 41 b, and the outer shape of both ends thereof is shown in FIG. As shown, the curved surface has substantially the same curvature as the fitting portion 41. The length L0 in the width direction of the stepped portion 41c is set to be slightly smaller than the distance D0 between the soaking blocks 17, 17 facing each other in FIG.

  The soaking blocks 17 and 17 have such a height that their upper surfaces protrude above the sample mounting portion 16 a of the heat sensitive plate 16 when they are fixed on the heat sensitive plate 16 with screws 13. That is, a recess is formed between the soaking blocks 17 and 17 and the sample mounting portion 16a. When the jig 41 is fitted into the partition wall 8 while the fitting portion 41b of the jig 41 is fitted to the inner peripheral surface of the partition wall 8, the stepped portion 41c of the jig 41 has the soaking blocks 17 and 17 and the sample mounting. The whole is inserted into a recess formed by the mounting portion 16a. In this case, the relationship between the stepped portion 41c and the recessed portion is not a fitting state without rattling, such as fitting between the fitting portion 41b of the jig 41 and the inner peripheral surface of the partition wall 8. Therefore, the jig 41 fitted in the inner peripheral surface of the partition wall 8 has an angular range in which the outer peripheral surface of the stepped portion 41c hits the soaking blocks 17 and 17 and its rotational movement is restricted. Rotational movement is possible.

  As shown in FIG. 6A and FIG. 6B, circular holes 43 are provided in the bottom wall of the stepped portion 41c at both ends in the longitudinal direction of the stepped portion 41c. These holes 43 are centered on the sample placement areas Fa and Fb on the sample placement portion 16a of the heat sensitive plate 16 in FIG. 3 when the jig 41 is fitted into the partition wall 8 in FIG. It is formed where it can match the center. The diameter of the holes 43 is such that the sample container 24 can be inserted and the sample container 24 can be positioned, specifically, about 0.5 mm to 1.0 mm from the outer peripheral surface of the sample container 24. Large dimensions are set.

  As shown in FIG. 6A, two position measurement holes 42 are provided between the pair of holes 43. These holes 42 are centered on the gas holes 19a and 19b on the sample mounting portion 16a of the heat sensitive plate 16 of FIG. 3 when the jig 41 is fitted into the partition wall 8 in FIG. It is formed where you can match.

  As is clear from the above, the positional relationship between the hole 43 formed in the bottom wall of the step portion 41 c of the jig 41 and the position measurement hole 42 is determined by the sample placement area Fa in the sample placement portion 16 a of the heat sensitive plate 16. The positional relationship between Fb and the gas holes 19a and 19b is the same. The position measuring hole 42 is a hole for confirming the position with respect to the gas holes 19a and 19b. Therefore, if the position measuring hole 42 is formed to be significantly smaller than the gas holes 19a and 19b, the purpose may not be achieved. The size of the position measurement hole 42 is preferably set to be approximately the same as or slightly larger than the gas holes 19a and 19b.

  The operation of the thermal analyzer having the above configuration will be described below. First, in FIG. 2, the heat insulating case 4 is removed, the lid 21 is further removed, and the measurement sample 22 and the reference stored in the sample container 24 on the heat sensitive plate 16 in the sample chamber R, particularly on the sample mounting portion 16a. The substance 23 is placed. Thereafter, the lid 21 is put on the partition wall 8 and the heat insulating case 4 is put on the measuring unit 3.

  Thereafter, the heater wire 7 is supplied with power according to a predetermined program to generate heat, and the heat is transferred to the partition wall 8 to raise the temperature. When the temperature of the partition wall 8 is increased, heat is transmitted from the bottom wall 8a to the heat sensitive plate 16 through the base 15, and the heat sensitive plate 16 is heated. Then, the heat of the heat sensitive plate 16 is transmitted to the measurement sample 22 and the reference material 23 through the sample container 24. Thereby, the temperature of the measurement sample 22 and the reference material 23 is raised or lowered according to a predetermined program.

  The reference material 23 is formed of a thermally stable material, and physical properties such as melting and evaporation do not change even when the temperature changes. On the other hand, when the measurement sample 22 changes its physical properties in response to the temperature change according to its own characteristics, a temperature difference is generated between the measurement sample 22 and the reference material 23.

  In FIG. 5, the temperature of the measurement sample 22 and the reference material 23, particularly the surface temperature, is detected by the thermocouple 26 and sent to the temperature difference measurement circuit 29 as a temperature signal. The temperature difference measurement circuit 29 calculates a temperature difference ΔT between the measurement sample 22 and the reference material 23 based on the sent temperature signal, and sends the calculation result to the calorific value calculation circuit 30. The calorific value calculation circuit 30 calculates the heat flow rate flowing into the measurement sample 22 based on the temperature difference ΔT, and thus the calorific value. The calculated heat quantity is displayed on the video display device 31 as a function of the measurement time or the temperature in the sample chamber R, or is output by the printer 32. Based on this display, the temperature dependence of the measurement sample 22 can be known.

  By the way, when the measurement is performed using the thermal analysis apparatus as described above, the sample container 24 is accurately placed in the regions Fa and Fb on the sample placement portion 16a as shown in FIG. It may be necessary to make a measurement. For example, this is the case when specific heat measurement is performed.

  Here, the specific heat measurement is the following measurement. That is, first, as shown in FIG. 5, there are three types of samples: an empty sample container 24a, a sample container 24b containing a substance 22b whose specific heat capacity is known, and a sample container 24c containing a sample 22c whose specific heat is to be measured. Prepare the container. Then, each of the sample containers 24a, 24b, and 24c is individually placed on the heat sensitive plate 16, and the change in the amount of heat is measured. That is, the measurement is performed three times in total, once for each of the three types of sample containers 24a, 24b, and 24c. The specific heat of the measurement sample 22c is obtained based on the results obtained by these three measurements.

  Normally, when performing measurement using a thermal analyzer, the measurer has visually determined the position where the sample container 24 is placed. That is, the areas Fa and Fb on the sample placement unit 16a are visually determined. In this case, the position where the sample container 24 is placed may change every time the sample container 24 is replaced. In a measurement that is normally performed, a change in the placement position of the sample container 24 that occurs by visual judgment is in a range that does not cause a problem. However, in the specific heat measurement, since the measurement result depends on the position where the sample container 24 is placed, the measurement result needs to be reproducible. Therefore, there is a possibility that accurate measurement cannot be performed by visual judgment. According to the thermal analysis apparatus of the present embodiment using the jig 41 of FIG. 3, the thermal analysis measurement with high reproducibility is possible, which is very advantageous when performing the specific heat measurement as described above.

  Below, one Embodiment in the case of performing a specific heat measurement using the thermal analyzer of this embodiment is described. FIG. 7 shows a specific heat measurement method using a thermal analyzer in the order of steps. FIG. 8 shows in detail the step of placing the reference substance and the sample in the step of FIG. In this specific heat measurement, a total of three DSC processes are executed: the first DSC process P2, the second DSC process P5, and the third DSC process P8.

  First, in the process P1, the sample mounting process is executed for the empty sample container 24a in FIG. Specifically, in step P11 of FIG. 8, the heat insulating case 4 shown in FIG. 2 is removed, the lid 21 is further removed, and the sample chamber R of the measurement unit 3 is opened.

  Next, in step P12, the jig 41 shown in FIG. Specifically, the jig 41 is inserted into the opened sample chamber R. At this time, the inner peripheral surface of the partition wall 8 and the outer peripheral surface of the fitting portion 41b of the jig 41 are fitted. At the same time, both side surfaces G0 of the stepped portion 41c of the jig 41 and the side surfaces G1 of the two soaking blocks 17 facing the sample mounting portion 16a face each other. From this state, the jig 41 is further rotated so that the two position measurement holes 42 provided in the jig 41 and the gas holes 19a and 19b provided in the heat sensitive plate 16 coincide with a predetermined positional relationship. Adjust its position. With this adjustment, the positional relationship between the holes 43 and 43 of the jig 41 and the sample placement areas Fa and Fb of the heat sensitive plate 16 is set to a fixed positional relationship in FIG.

  Next, in step P13 of FIG. 8, the sample container 24d containing the reference material 23 of FIG. 5 and the empty sample container 24a are placed on the sample placement unit 16a. Specifically, in FIG. 3, the sample container 24d containing the reference material 23 is inserted into one of the two holes 43 provided in the jig 41 and placed on one of the placement areas Fa and Fb. Further, an empty sample container 24a is inserted into the other hole 43 and placed on the other of the placement areas Fa and Fb. Since the hole 43 is sized so that the sample containers 24a and 24d can be fitted without any backlash, the sample containers 24a and 24d placed on the sample placement part 16a of the heat sensitive plate 16 through these holes 43 are always placed in the placement region Fa. , Fb are accurately placed at predetermined positions.

  Next, in step P14 of FIG. 8, the jig 41 is removed from the sample chamber R while the sample container 24a and the sample container 24d are placed on the heat sensitive plate 16. Then, as shown in FIG. 4, the sample container 24d containing the reference material 23 and the empty sample container 24a are located on the sample mounting portion 16a of the heat sensitive plate 16 on the opposite sides of the gas holes 19a and 19b. Remain. Furthermore, in step P15 of FIG. 8, the lid 21 is put on the sample chamber R to close the sample chamber R as shown in FIG. 2, and the work of placing the sample by putting the heat insulating case 4 on the measuring unit 3 is finished. To do.

  Next, in the process P2 of FIG. 7, the first DSC is performed by the operation of the above-described thermal analyzer, and the amount of heat related to the empty sample container 24a is measured. After the completion of the first DSC, in step P3, the heat insulating case 4 shown in FIG. 2 is removed, the lid 21 is further removed, and the sample chamber R is opened. And the empty sample container 24a is removed from the heat sensitive plate 16, and the measurement with respect to the empty sample container 24a is complete | finished.

  Subsequently, in step P4 of FIG. 7, the sample container 24b containing the substance 22b having a known specific heat capacity shown in FIG. 5 is placed on the sample placement portion 16a. This sample placement process P4 is performed in the same procedure as the placement process P1 related to the empty sample container 24a. However, in the process P4, the sample container 24d that already contains the reference substance 23 is placed at a predetermined position. Therefore, the jig 41 fits one of the holes 43 and 43 in FIG. It is inserted into the partition wall 8.

  Next, in the process P5, the second DSC is executed. In the first DSC, the measurement was performed on the empty sample container 24a. In the second DSC, a substance 22b having a known specific heat capacity is accommodated in the sample container 24b, and measurement is performed on the substance 22b. That is, the temperature detected by the thermocouple 26 is the temperature of the material 22b and the reference material 23 whose specific heat capacities are known, and the same operation as the first DSC is performed for these materials. Then, in step P6 of FIG. 7, the heat insulating case 4 and the lid 21 are removed to open the sample chamber R, the sample container 24b is removed from the heat sensitive plate 16, and the measurement is finished.

  Next, in step P7, in the same manner as in steps P1 and P4, the sample container 24c containing the sample 22c whose specific heat is to be measured is placed on the sample placing portion 16a. In step P8, the third DSC is executed. In the third DSC, the sample 22c whose specific heat is to be measured is accommodated in the sample container 24c, and measurement is performed on the sample 22c. That is, the temperature detected by the thermocouple 26 is the temperature of the sample 22c and the reference material 23 whose specific heat is to be measured, and the same operation as the first DSC and the second DSC is performed for these materials. Thereafter, the specific heat of the measurement sample 22c is obtained based on the three measurement results, and the process ends.

  In this embodiment, when the jig 41 is installed in the sample chamber R in FIG. 1, the outer peripheral surface of the fitting portion 41 b of the jig 41 and the inner peripheral surface of the sample chamber R, that is, the inner peripheral surface of the partition wall 8. And the partition wall 8 serves as a guide member when the jig 41 is installed in the sample chamber R. Thereby, the jig 41 can be accurately installed at a predetermined position with respect to the heat sensitive plate 16. Further, since the partition wall 8 is used as a guide member, it is not necessary to newly install a guide member, and the structure of the measurement unit 3 can be simplified.

  Further, in the present embodiment, in the sample chamber R, the step portion 41a of the jig 41 is fitted into the heat equalizing block 17 protruding upward from the sample mounting portion 16 of the heat sensitive plate 16. At this time, the side surface G0 of the stepped portion 41c of the jig 41 and the surface G1 of the soaking block 17 on the side of the sample mounting portion 16a face each other, but do not need to contact each other. In other words, the fitting here may have a backlash. By fitting the step portion 41 a and the heat equalizing block 17, the approximate position of the jig 41 with respect to the heat sensitive plate 16 can be determined.

  In the present embodiment, two holes 43 and two position measurement holes 42 are provided on the bottom surface of the stepped portion 41a. As described above, the positions of the holes 43 and the position measurement holes 42 are in the same relationship as the positions of the sample placement areas Fa and Fb (see FIG. 3) and the gas holes 19a and 19b in the sample placement portion 16a. is there. In other words, if the jig 41 is installed in the sample chamber R so that the positions of the two position measurement holes 42 are aligned with the gas holes 19a and 19b, the two holes 43 are located above the placement areas Fa and Fb, respectively. Located in. Therefore, if the sample container 24c containing the measurement sample 22c of FIG. 5 and the sample container 24d containing the reference material 23 are inserted into the holes 43 and 43 of FIG. It can be accurately placed on the placement areas Fa and Fb. As a result, it is possible to maintain high reproducibility of measurement results in measurement using a thermal analyzer.

(Other embodiments)
The present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the embodiments, and various modifications can be made within the scope of the invention described in the claims.

  For example, in the embodiment described above, the heat flux type DSC apparatus is exemplified. However, the present invention can also be applied to other thermal analysis apparatuses that perform measurement by placing a sample on a heat sensitive plate, for example, a DTA apparatus.

  Moreover, in the above-described embodiment, a case where specific heat measurement is performed using a DSC apparatus has been exemplified. However, the present invention can also be applied to other measurements that require measurement in a state where the sample container is accurately placed at a predetermined position on the heat sensitive plate. For example, the present invention can also be applied to a case where a quality control department performs a quality check on many substances of the same type. Of course, the sample container placing method using the jig 41 may be performed on a general DSC in which there is only one kind of substance to be measured.

  In the above embodiment, the hole 43 of the jig 41 for placing the measurement sample on the heat sensitive plate 16 of FIG. 3 is a circular hole slightly larger than the outer diameter of the sample container 24. However, the shape of the hole 43 is large enough to allow the sample container 24 to be taken in and out, and is larger than the sample container 24 to such an extent that variations in the reproducibility of the measurement results using the thermal analyzer fall within an allowable range. If so, it does not have to be circular. For example, it can be a square hole.

  Further, in the above embodiment, two holes 43 of the jig 41 for placing the measurement sample on the heat sensitive plate 16 of FIG. 3 are provided in the bottom wall of the step portion 41 c of the jig 41. However, only one hole 43 may be provided. In this case, the hole 43 is not limited to the end portion in the longitudinal direction of the bottom wall of the step portion 41c, and is provided at an appropriate position according to the position where the sample is placed.

  INDUSTRIAL APPLICABILITY The present invention is suitably used in a thermal analyzer that performs measurement by placing a sample on a heat sensitive plate, for example, a DSC device, when it is necessary to always place a sample container containing the sample at a certain position on the heat sensitive plate. It is done.

It is sectional drawing which shows the principal part of the thermal analyzer which concerns on this invention. It is sectional drawing which shows the DSC apparatus which is a part of one Embodiment of the thermal analyzer which concerns on this invention. It is a perspective view which shows the jig | tool which is another part of one Embodiment of the thermal analyzer which concerns on this invention. It is a top view which shows the principal part of the thermal analyzer of FIG. 2, especially a measurement part unit. FIG. 3 is a block diagram showing an electrical control system of the thermal analysis apparatus of FIG. 2. It is a figure which shows the jig | tool of FIG. 3, (a) shows the top view, (b) has shown sectional drawing according to the AA line of (a). It is process drawing which shows one Embodiment of the thermal-analysis method based on this invention. It is process drawing which shows an example of the content of the main processes of FIG.

Explanation of symbols

1. 1. Housing table, 2. base block; Measuring unit,
4). 6. heat insulation case; 7. Heater wire Partition wall (guide member), 8a. 10. Bottom wall of the partition wall Set screw, 15. Stand, 16. Heat sensitive plate, 16a. Sample mounting section,
16b. Fixing part, 17. Soaking block, 18. Through holes, 19a, 19b. Gas hole, 20. Through hole, 21. Lid, 22. Measurement sample, 23. Reference material, 24. Sample container, 25. Isogo tube, 26. Thermocouple bundle, 28. Thermocouple wires, 31. Video display device,
35. Feeding line, 37. Feeding circuit, 38, gas pipe, 39. Gas introduction terminal,
40. DSC apparatus (thermal analysis apparatus), 41. Jig (thermal analysis device), 41a. Flange, 41b. Fitting part, 41c. Step part, 42. Position measurement hole, 43. hole,
R. Sample chamber, G0. Side surface of step, G1. Soaking block side

Claims (6)

A thermal plate on which a sample container is placed;
A jig provided with a hole into which the sample container can be inserted and the sample container can be positioned;
A thermal analysis apparatus comprising: a guide member that removably supports the jig at a predetermined position with respect to the heat sensitive plate.   2. The thermal analyzer according to claim 1, further comprising a partition wall forming a sample chamber in which the heat sensitive plate is disposed, and the guide member is the partition wall.   3. The thermal analysis apparatus according to claim 1, wherein the jig has an outer peripheral surface that is fitted to an inner peripheral surface of the guide member.   4. The thermal analysis apparatus according to claim 1, wherein the thermal plate further includes a gas hole for allowing a gas to pass therethrough, and the jig is used for measuring a position with respect to the gas hole. 5. A thermal analyzer having a position measurement hole.   5. The thermal analysis apparatus according to claim 1, further comprising a soaking block that protrudes above a sample container mounting surface of the thermal plate, wherein the jig includes the thermal plate. A thermal analyzer having a stepped portion that fits into the soaking block at a portion protruding from the heat sink. In the thermal analysis method for measuring in a state where the sample container containing the sample is placed on the heat sensitive plate,
Place a jig with a hole into which the sample container can be inserted and the sample container can be positioned at a predetermined position with respect to the heat sensitive plate,
Place the sample container on the heat sensitive plate through the hole,
A thermal analysis method, wherein the jig is removed from the heat sensitive plate while the sample container is placed on the heat sensitive plate.

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