JP7215375B2 - thermal analyzer - Google Patents

Description

The present invention relates to thermal analysis equipment such as differential thermal analyzer (DTA), thermogravimetric analyzer (TGA), thermomechanical analyzer (TMA), differential scanning calorimeter (DSC), and the like.

Thermal analysis includes various techniques such as differential thermal analysis, thermogravimetry, thermomechanical analysis, and differential scanning calorimetry. For example, differential thermal analysis is a method of measuring the temperature difference between a sample and a reference substance as a function of temperature while changing the temperatures of the sample and the reference substance according to a certain program. Phenomena that accompany endothermic and exothermic phenomena are the objects of measurement. In addition, thermogravimetry is a method of measuring the change in weight of a sample when the sample is heated or cooled at a constant rate, or when the sample is kept at a constant temperature. A chemical or physical change that accompanies a weight change with temperature, such as adsorption, is the object of measurement. For example, Non-Patent Document 1 discloses an apparatus that has both the functions of differential thermal analysis and thermogravimetry and is capable of performing both measurements simultaneously.

Regardless of the method, in such a thermal analysis apparatus, the sample is stored in a heating furnace and heated to a predetermined temperature (for example, about 1500° C.), or conversely, cooled from a high temperature state, and the sample is cooled. Analyze the heat change that occurs in the sample. In order to perform analysis accompanying such temperature changes, in a conventional thermal analysis apparatus, a user presets a measurement program including a temperature profile showing temperature changes over time using a personal computer connected to the apparatus. Then, when the user gives an instruction to start measurement, heating or cooling is automatically performed according to the set measurement program.

In such a thermal analysis apparatus, when measurements are performed without oxidizing the sample, in order to remove oxidizing gases such as oxygen in the heating furnace, the gas inside the heating furnace is expelled with an inert gas such as nitrogen before starting the measurement. (see Patent Document 1, etc.). As the gas used for this atmosphere replacement, helium, argon, etc. may be used in addition to nitrogen, etc., depending on the purpose of measurement.

JP-A-8-152419 (paragraphs [0014]-[0015])

"DTG-60/60H series TG/DTA simultaneous measurement device", [online], Shimadzu Corporation, [searched on August 13, 2019], Internet <URL: https://www.an.shimadzu.co. jp/ta/dtg60.htm>

In the conventional thermal analysis apparatus, the measurement itself is automatically performed according to the measurement program, but the user has to manually replace the atmosphere before the measurement. Therefore, not only must the operator operate the flow valve to supply the inert gas, but also wait until the atmosphere in the heating furnace is sufficiently replaced with the inert gas before starting measurement. It is necessary to perform an operation for If an operator is involved in such work, the efficiency of measurement will be lowered, and there is a possibility that the operator will make a mistake such as starting the measurement even though the replacement of the atmosphere is insufficient.

The present invention has been made to solve the above problems, and its main purpose is to reduce the burden on the operator (user) during measurement, improve the efficiency of the measurement work, and reduce the inconvenience caused by work mistakes. An object of the present invention is to provide a thermal analysis apparatus capable of preventing the execution of appropriate measurements.

A thermal analysis apparatus according to one aspect of the present invention, which has been made to solve the above problems, includes a heating furnace in which a sample to be measured is accommodated, a heating control unit that controls heating of the heating furnace, and A thermal analysis apparatus comprising a gas supply unit for supplying a predetermined gas to the inside of the heating furnace,
a measurement condition setting unit that allows a user to set measurement conditions including a temperature profile that indicates the relationship between the passage of time and temperature;
an atmosphere replacement condition setting unit that allows a user to set atmosphere replacement conditions including the type of gas to be used, gas flow rate, replacement time, and stabilization waiting time when the atmosphere is replaced prior to measurement;
After receiving a user's instruction and replacing the atmosphere in the heating furnace by controlling the gas supply unit according to the atmosphere replacement conditions set by the atmosphere replacement condition setting unit, subsequently, the measurement condition setting unit a control unit that controls the gas supply unit and the heating control unit according to the measurement conditions set by the
is provided.

The setting of the measurement conditions by the measurement condition setting unit and the setting of the atmosphere replacement conditions by the atmosphere replacement condition setting unit may be performed substantially simultaneously (that is, together), or may be performed separately. good too.

In the thermal analysis apparatus of the above-described aspect of the present invention, the user sets the measurement conditions and the atmosphere replacement conditions appropriately in advance. A series of actions can be automatically executed. As a result, the operator does not need to operate the gas flow valve for atmosphere replacement, nor does it need to wait until the atmosphere replacement is completed. According to the thermal analysis apparatus of the above aspect of the present invention, the burden on the operator during measurement can be reduced, the efficiency of the measurement work can be improved, and inappropriate measurement due to work mistakes can be prevented. can.

1 is a configuration diagram of a main part of a differential thermal analysis apparatus that is an embodiment of the present invention; FIG. FIG. 4 is a diagram showing an example of a change in gas flow rate over time in the differential thermal analysis apparatus of the present embodiment;

A differential thermal analysis apparatus according to an embodiment of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a configuration diagram of the main part of the differential thermal analysis apparatus of this embodiment.

The differential thermal analysis apparatus of this embodiment includes a heating section 1, an atmospheric gas supply section 2, a heating control section 3, an analysis control section 4, a control section 5, an input section 6, and a display section 7. The heating unit 1 includes a substantially cylindrical heating furnace 10 containing the sample S and the reference material R, a radiation shield 11 surrounding the heating furnace 10 , and a heat insulating cover 12 surrounding the radiation shield 11 . Furnace 10 is made of a heat-resistant material, typically ceramic. A heater wire 10 a is wound around the heating furnace 10 , and the heating furnace 10 is heated by supplying a heating current to the heater wire 10 a from the heating control section 3 . A gas introduction pipe 14 is connected to the heating furnace 10 for introducing a predetermined gas thereinto.

The weights of the sample S and the reference material R are measured by a weight measuring unit (not shown). A temperature difference between the sample S and the reference material R is also detected by a thermocouple (not shown) or the like.

The atmospheric gas supply unit 2 is prepared by the user and includes two gas supply sources (such as gas cylinders) 20 and 21 connected to two gas supply ports 22 and 23, respectively, and two auto flow devices for adjusting the flow rate of each gas. A controller (AFC) 24, 25 is included. The control unit 5 includes a measurement condition setting unit 50 , an atmosphere replacement condition setting unit 51 , a measurement program storage unit 52 and an atmosphere replacement condition storage unit 53 .

The analysis control unit 4 is integrated with the heating unit 1, the heating control unit 3, etc., and is mainly composed of a microcomputer including a CPU, a ROM, a RAM, a timer, and the like. On the other hand, the substance of the control unit 5 is a general-purpose personal computer (PC), and the functions described above are realized by running control/processing software installed in the PC on the PC. be able to.

Next, the user's operation/work and the operation of the apparatus when performing measurement using the differential thermal analysis apparatus of this embodiment will be described. FIG. 2 is a diagram showing an example of change in gas flow rate over time.
The sample S and the reference material R to be measured are respectively placed on the mounting trays above the detector 13 while the heating furnace 10 is raised by a mechanism (not shown). When the sample S and the reference material R are set, the heating furnace 10 is lowered so that the sample S and the reference material R are contained therein.

When the operator performs a predetermined operation on the input unit 6, the atmosphere replacement condition setting unit 51 first prompts the operator to input the type of gas connected to the two gas supply ports 22 and 23 as initial environment setting. . Usually, the type of gas used for thermal analysis is fixed, not limited to the purpose of atmosphere replacement, so options for selecting the type of gas are prepared, and the gas supply ports 22 and 23 are connected to The operator should be allowed to select the type of gas. If the types of gases connected to the gas supply ports 22 and 23 are not changed, this setting process can be omitted.

When the operator further performs a predetermined operation on the input unit 6, the atmosphere replacement condition setting unit 51 displays an atmosphere replacement condition setting screen in a predetermined format on the display unit 7, and prompts the operator to input atmosphere replacement conditions. The atmosphere replacement conditions include the type of gas used for atmosphere replacement, gas flow rate La, replacement time ta, device stabilization waiting time tb, and the like.

Since the type of gas can only be selected from the two types of gas connected to the gas supply ports 22 and 23, the operator is presented with the two types of gas set in the previous environment setting as choices, and The operator should be allowed to select one of them. The gas flow rate La is the flow rate of the gas introduced into the heating furnace 10 when the atmosphere is replaced, and may be input numerically by the operator. The replacement time ta is the time during which the gas at the gas flow rate La is continuously introduced into the heating furnace 10 during atmosphere replacement, and may be input by the operator as a numerical value. Further, the device stabilization waiting time tb is the time to wait for the device to reach a stable state with the flow rate of the gas introduced into the heating furnace 10 changed to the gas flow rate at the time of measurement after the end of the replacement time ta. , this may also be done by having the operator input numerical values.

Nitrogen is generally widely used as the gas for atmosphere replacement, but other inert gases such as helium and argon may also be used. In addition, numerical values such as the gas flow rate vary depending on the size of the heating furnace 10, etc., but as a typical example of the thermal analysis apparatus described in Non-Patent Document 1, the gas flow rate is 300 mL / min, the replacement time is 30 min, and the device is stable. It is possible to set the waiting time for conversion to about 3 minutes.
When the input setting of the atmosphere replacement condition is confirmed, the atmosphere replacement condition setting unit 51 temporarily stores the set atmosphere value replacement condition as a file in the atmosphere replacement condition storage unit 53 .

When the operator performs another predetermined operation on the input section 6, the measurement condition setting section 50 displays a measurement condition setting screen in a predetermined format on the display section 7 and prompts the operator to input the measurement conversion conditions. The measurement conditions include a temperature profile that shows the relationship between elapsed time and temperature, the type of gas used during measurement (however, the type of gas may be switched during measurement, and the type of gas may be switched during measurement), and the flow rate of gas La and so on. As in the atmosphere replacement, the gas type can be selected only from the two types of gases connected to the gas supply ports 22 and 23, so the two types of gases set in the previous environment setting are selected as options. It suffices to present them to the worker and allow the worker to select one of them. The gas flow rate Lb is the flow rate of the gas introduced into the heating furnace 10 at the time of measurement, and may be input numerically by the operator. For example, when the gas flow rate during atmosphere replacement is 300 mL/min as described above, the gas flow rate during measurement is about 50 mL/min.

When the input setting of the measurement conditions is confirmed, the measurement condition setting unit 50 temporarily stores the set measurement conditions as a file in the measurement program storage unit 52 .
It should be noted that the atmosphere replacement conditions and the measurement conditions may be input and set on the same setting screen. Alternatively, both conditions may be treated as one and stored in one file.

In some cases, measurements are repeated for different samples without changing the measurement conditions and atmosphere replacement conditions. Atmosphere replacement conditions can be called and used. As a result, when the measurement conditions and atmosphere replacement conditions are not changed, or when the measurement conditions and atmosphere replacement conditions that have been used in the past are used again, it is possible to save the trouble of inputting and setting parameters and the like.

When the operator instructs the start of measurement with the input unit 6 in a state in which the measurement conditions and atmosphere replacement conditions to be used have been determined, the control unit 5 receives this instruction, and the determined measurement conditions and atmosphere replacement conditions are sent to the analysis control unit. Send to 4. The analysis control unit 4 first controls the operation of the auto flow controllers 24 and 25 in the atmosphere gas supply unit 2 based on the information on the gas type and gas flow rate La under the atmosphere replacement condition, and the heating furnace through which the gas introduction pipe 14 is passed. Start supplying gas to 10 . That is, either one of the two auto-flow controllers 24 or 25 is selected according to the set gas type, and the gas whose flow rate is adjusted by the selected auto-flow controller 24 or 25 is allowed to flow. As a result, as shown in FIG. 2, a predetermined gas is supplied into the heating furnace 10 at a gas flow rate La from the start of replacement, and the gas (air) remaining in the heating furnace 10 before that time is discharged to the outside. begin to be

The analysis control unit 4 counts time with a timer from the start of replacement, and when the replacement time ta has elapsed, the gas flow rate is reduced to the gas flow rate Lb at the time of measurement set as the measurement condition. The analysis control unit 4 counts time with a timer from the end of the replacement, and when the apparatus stabilization time tb has passed, the measurement according to the measurement program is started. Normally, the residual gas in the heating furnace 10 is completely replaced by the atmosphere gas when the replacement time ta has passed, and the apparatus stabilization time tb is set by keeping the flow rate of the gas in the same state as during the measurement. This is a period for stabilizing the state of the gas flow in 10 and the like.

When the measurement is started, the analysis control unit 4 controls the heating control unit 3. For example, in the case of temperature rising analysis, the heating current is supplied to the heater wire 10a, and the temperature of the heating furnace 10 is adjusted according to the specified temperature profile. to raise A thermal change occurring in the sample S during the temperature rising process is detected as a temperature difference between the sample S and the reference material R. FIG. When the measurement according to the measurement program is completed, the heating is stopped, and the heating furnace 10 is cooled by driving a fan (not shown).

As described above, in the differential thermal analysis apparatus of the present embodiment, after the operator gives an instruction to start measurement, a series of operations from the start of atmosphere replacement to the end of measurement are automatically performed without any operation or work by the operator. executed. In addition, atmosphere replacement is automatically performed in accordance with the contents set in advance as the atmosphere replacement conditions, so if the input settings are made appropriately, problems such as insufficient atmosphere replacement can be prevented from occurring.

In the description of the above embodiment, the control unit 5 sends both the atmosphere replacement conditions and the measurement conditions to the analysis control unit 4 at the start of measurement, and after that, the analysis control unit 4 controls the operation of each unit. The control unit 5 may directly control the operation during atmosphere replacement, that is, the adjustment operation of the gas supply amount in the atmospheric gas supply unit 2 .

In addition, the internal volume of the heating furnace 10 is usually known, and once the gas flow rate at the time of atmosphere replacement is determined, the approximate time required to replace the gas in the heating furnace 10 can be calculated. Therefore, when the operator inputs the replacement time ta, if the entered numerical value is too small compared to the approximate required replacement time that is automatically calculated, a warning is given that there is a possibility of insufficient replacement. You may make it display. Also, the range of numerical values that can be input by the operator may be limited based on the approximate time required for replacement that is automatically calculated. This can prevent erroneous input operations by the operator.

In addition, although the above embodiment is a differential thermal analysis device, the present invention can also be applied to other thermal analysis devices such as a thermogravimetry device, a thermomechanical analysis device, and a differential scanning calorimetry device. is clear.

Moreover, the above-described embodiment is an example of the present invention, and it is obvious that any further modifications, changes, and additions within the scope of the present invention are included in the scope of the claims of the present application.

[Various aspects]
Those skilled in the art will appreciate that the exemplary embodiments described above are specific examples of the following aspects.

(Section 1) One aspect of the thermal analysis apparatus according to the present invention includes a heating furnace in which a sample to be measured is accommodated, a heating control unit that controls heating of the heating furnace, and the heating furnace. A thermal analysis apparatus comprising a gas supply unit that supplies a predetermined gas to the inside,
a measurement condition setting unit that allows a user to set measurement conditions including a temperature profile that indicates the relationship between the passage of time and temperature;
an atmosphere replacement condition setting unit that allows a user to set atmosphere replacement conditions including the type of gas to be used, gas flow rate, replacement time, and stabilization waiting time when the atmosphere is replaced prior to measurement;
After receiving a user's instruction and replacing the atmosphere in the heating furnace by controlling the gas supply unit according to the atmosphere replacement conditions set by the atmosphere replacement condition setting unit, subsequently, the measurement condition setting unit a control unit that controls the gas supply unit and the heating control unit according to the measurement conditions set by the
is provided.

According to the thermal analysis apparatus of item 1, the operation of replacing the atmosphere in the heating furnace and the measurement operation can be automatically performed in a series only by the user giving an instruction to start measurement, for example. As a result, the operator does not need to operate the gas flow valve for atmosphere replacement, nor does it need to wait until the atmosphere replacement is completed. In this way, the burden on the operator during measurement can be reduced, the efficiency of the measurement work can be improved, and inappropriate measurement due to work mistakes can be prevented.

(Section 2) The thermal analysis apparatus described in Section 1 further includes a measurement condition storage unit that stores the measurement conditions set by the measurement condition setting unit, and the measurement condition setting unit provides the user with the measurement conditions. is set, the measurement conditions already stored in the measurement condition storage unit can be presented so that the measurement conditions can be used as they are as the next measurement conditions.

According to the thermal analysis apparatus described in paragraph 2, when performing analysis again using the previously used measurement conditions, the user does not need to input and set the measurement conditions, improving the efficiency of the measurement work. can be done.

(Item 3) The thermal analysis apparatus according to item 1 or 2 further includes a gas type setting unit that allows a user to set the type of one or more gases prepared in the gas supply unit, wherein the atmosphere The replacement condition setting unit and/or the measurement condition setting unit may present the type of gas set by the gas type setting unit to the user as the type of usable gas.

According to the thermal analysis apparatus of the third aspect, only usable gas types can be presented to the user, so it is possible to prevent the user from setting an inappropriate gas type.

(Item 4) In the thermal analysis apparatus according to any one of items 1 to 3, the control unit controls the type of gas, gas flow rate, and replacement time set as the atmosphere replacement conditions. Accordingly, after replacing the atmosphere in the heating furnace with a predetermined gas, the gas flow rate is changed to the gas flow rate set as the measurement condition, and then the stabilization waiting time set as the atmosphere replacement condition Waiting may be followed by subsequent measurements.

According to the thermal analysis apparatus described in item 4, since the measurement can be performed after the gas flow in the heating furnace becomes stable, the influence of the unstable gas flow during the measurement can be eliminated, and highly accurate measurement can be performed.

DESCRIPTION OF SYMBOLS 1... Heating part 10... Heating furnace 10a... Heater wire 11... Radiation shield 12... Heat insulation cover 14... Gas introduction pipe 2... Atmospheric gas supply part 3... Heating control part 4... Analysis control part 5... Control part 50... Measurement condition setting Part 51... Atmosphere replacement condition setting part 52... Measurement program storage part 53... Atmosphere replacement condition storage part 6... Input part 7... Display part

Claims (4)

Heater comprising a heating furnace in which a sample to be measured is accommodated, a heating control section for controlling heating of the heating furnace, and a gas supply section for supplying a predetermined gas to the interior of the heating furnace. an analytical device,
a measurement condition setting unit that allows a user to set measurement conditions including a temperature profile that indicates the relationship between the passage of time and temperature;
an atmosphere replacement condition setting unit that allows a user to set atmosphere replacement conditions including the type of gas to be used, gas flow rate, replacement time, and stabilization waiting time when the atmosphere is replaced prior to measurement;
After receiving a user's instruction and replacing the atmosphere in the heating furnace by controlling the gas supply unit according to the atmosphere replacement conditions set by the atmosphere replacement condition setting unit, subsequently, the measurement condition setting unit a control unit that controls the gas supply unit and the heating control unit according to the measurement conditions set by the
A thermal analysis device comprising a A measurement condition storage unit for storing the measurement conditions set by the measurement condition setting unit is further provided , and the measurement condition setting unit stores the measurement conditions already stored in the measurement condition storage unit when allowing the user to set the measurement conditions. 2. The thermal analysis apparatus according to claim 1, wherein a current measurement condition is presented, and the measurement condition can be used as the next measurement condition as it is.
a gas type setting unit that allows a user to set the type of one or more gases prepared in the gas supply unit; The thermal analysis apparatus according to claim 1 or 2, wherein the set gas type is presented to the user as a usable gas type. The control unit replaces the atmosphere in the heating furnace with a predetermined gas according to the type of gas, gas flow rate, and replacement time set as the atmosphere replacement conditions, and then sets the gas flow rate as the measurement condition. The heat according to any one of claims 1 to 3, wherein after changing to the set gas flow rate, waiting for the stabilization waiting time set as the atmosphere replacement condition, and subsequently performing the measurement. Analysis equipment.

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