JP2001183319A - Thermal analyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal analyzer capable of observing a sample in a heating furnace even in the case of thermally analyzing the sample in a low temperature range of the ambient temperature or lower. SOLUTION: At least partial area of the cover 1b of the heating furnace 1 for containing the sample S and a reference sample R and at least partial area 5a of a heating furnace cover 5 directly above the partial area of the cover 1b are formed of transparent materials. The analyzer comprises a heater 8 for heating the vicinity of the furnace 1, and purge gas supply tubes 9a, 9b for supplying purge gases toward the materials 1b, 5a. Thus, even when the sample S in the furnace 1 is set to the low temperature and thermally analyzed, the furnace 1 can be observed therein without dew formation or without frost adhesion to the materials 1b, 5a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermal analyzer such as a differential scanning calorimeter.

[0002]

2. Description of the Related Art In a thermal analyzer such as a differential scanning calorimeter, a sample to be measured and a reference sample are generally accommodated in a heating furnace, and both of them are changed under the same thermal environment. A DSC (differential scanning calorimetry) sensor or the like provided therein detects information on the instantaneous temperature difference between the sample and the reference sample, and measures the thermal properties such as phase transition and melting of the sample. In order to improve the temperature distribution of such a heating furnace for heating a sample, the upper end of the heating furnace is usually closed with a metal lid, and a heating furnace cover is further placed thereon. Can be

[0003] In addition, in order to perform measurement in a temperature range of room temperature or lower, an apparatus of this type having a cooling means for directly or indirectly cooling the vicinity of a heating furnace has been put into practical use. As such a cooling means, those using a refrigerant tank using liquid nitrogen as a refrigerant and those using an electric cooler using a compressor other than liquid nitrogen and a compressor are known.

[0004]

In a thermal analyzer such as a differential scanning calorimeter as described above, the lid for closing the upper end of the heating furnace and the heating furnace cover to be covered from above are made of metal. Therefore, it is not possible to see the situation inside the heating furnace during the measurement.

[0005] Here, the condition of the temperature rise and fall of the sample is determined by DSC.
Although it is clear from the DSC curve output from the sensor, in order to more reliably and objectively evaluate the change in the state such as the phase change of the sample occurring in the heating furnace, the sample is directly observed together with the DSC curve. Is often very effective. To directly observe the sample in the heating furnace, a lid that covers the upper end of the heating furnace and a part of the heating furnace cover that covers the upper part of the heating furnace are made of a transparent body, and the inside can be viewed visually or photographed with a camera. What is necessary is just to make it.

[0006] However, even when the transparent body is provided on the lid of the heating furnace and the heating furnace cover, when measurement is performed in a temperature range of room temperature or lower, water vapor condenses on the transparent body, or The frost will adhere, making it virtually impossible to see the condition of the sample in the heating furnace.

The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a thermal analyzer capable of observing a sample in a heating furnace even when measuring in a low temperature range below room temperature.

[0008]

In order to achieve the above object, a thermal analyzer according to the present invention comprises a heating furnace for receiving and heating a sample and a reference sample, and a heating furnace for covering the heating furnace from above. Furnace cover, placed in the heating furnace,
In a thermal analysis apparatus including a sensor that detects information on an instantaneous temperature difference between a sample and a reference sample, and a cooling unit that cools the heating furnace so as to enable measurement in a temperature region equal to or lower than room temperature, At least a partial region of the lid closing the upper end of the heating furnace, and at least a partial region of the heating furnace cover immediately above the region are formed of transparent bodies, respectively, and the heating furnace and the heating furnace cover A heater for heating the vicinity and a gas supply pipe for supplying a purge gas toward the transparent body of the heating furnace and the heating furnace cover are provided (claim 1).

Here, in the present invention, in addition to the above configuration, the heating furnace and the transparent body of the heating furnace cover are provided above the transparent body.
A configuration in which a microscope and a camera for taking an image of the inside of the heating furnace through the microscope are provided, and image processing means for imaging a video signal from the camera and displaying the image on a display device (claim Item 2) can be adopted.

According to the present invention, by forming at least a part of the heating furnace and the heating furnace cover with a transparent body, visibility inside the heating furnace is imparted, and at the same time, dew condensation and frost adhesion to the respective transparent bodies are prevented. By providing the means, the intended purpose is to be achieved.

That is, by providing a heater for heating the vicinity of the heating furnace and the heating furnace cover, the surface temperatures of the heating furnace and the heating furnace cover are increased, and dew condensation and frost adhesion to the heating furnace and the heating furnace cover are prevented. Can be prevented. Further, by supplying a purge gas such as dry nitrogen gas to the transparent body of the heating furnace and the heating furnace cover, the above-described effect of preventing dew condensation and frost adhesion by the heater is further ensured. Can be.

[0012] Further, as described in the second aspect of the present invention, the inside of the heating furnace is photographed by a camera through a microscope and displayed on a display through the transparent body in which condensation and frost are prevented from adhering as described above. When the configuration is adopted, it is possible to record the state of the sample in the heating furnace with time, and by collating the record in relation to the DSC signal or the like, the information can be effective information for analysis. Further, when taking an image of the inside of the heating furnace by such a camera, supplying the purge gas such as the dry nitrogen gas to the transparent body described above,
This is extremely effective for sharpening the obtained image.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an embodiment of the present invention, and is a diagram illustrating both a schematic diagram schematically illustrating a mechanical configuration and a block diagram illustrating an electrical configuration.

The heating furnace 1 is heated as a whole by driving a heater 2 disposed below the heating furnace 1 and is in close contact with a heat transfer plate 3 also disposed below. On the heat transfer plate 3, a coolant tank 4 is mounted on the upper surface of the heat transfer plate 3 in close proximity to the contact portion with the heating furnace 1, and the heating furnace 1 and the coolant tank 4 are thermally connected to each other via the heat transfer plate 3. Is joined to.

The heating furnace 1 has a heating furnace body 1 having an open upper part.
a and a lid 1b for closing the opening at the upper end thereof, and a cup-shaped heating furnace cover 5 is further covered from above to cover the entire heating furnace 1.

The heating furnace 1 has a space for accommodating the sample to be measured S and the reference sample R in a thermal environment equivalent to each other, and has a temperature for detecting the temperature in the furnace. A sensor 6 and a DSC sensor 7 for detecting temperature difference information between the sample S to be measured and the reference sample R are arranged. The furnace temperature detection signal from the temperature sensor 6 is taken into a temperature control circuit 11, and the temperature control circuit 11 controls the heating so that the detection result of the furnace temperature rises at a preset speed. The heater 2 is driven and controlled. The output of the DSC sensor 7 is an amplifier and an A-D
After being amplified and digitized by the measuring circuit 12 composed of a converter, the interface 1
3 and is fetched into the personal computer 14 every moment. Note that the personal computer 14 is also configured to supply target data for temperature control to the temperature control circuit 11.

The lid 1b of the heating furnace 1 is a transparent body made of quartz glass.
A transparent window 5a also made of quartz glass is provided on the upper wall of the heating furnace 1 so as to correspond to a portion immediately above the lid 1b of the heating furnace 1. Therefore, the inside of the heating furnace 1 can be visually recognized from the outside via the transparent window 5a and the lid 1b. A sample imaging device including a stereo microscope 21, a CCD camera 22, and an illuminating lamp (not shown) is disposed directly above the transparent window 5 a of the heating furnace cover 5 while being supported by a dedicated stand (not shown). ing.

A video signal from the CCD camera 22 is sent to an image processing board 15 such as a capture board to be converted into an image, and then taken into the personal computer 14. In the personal computer 14, the image information captured via the image processing board 15 is displayed on the attached display device 1.
6 is displayed every moment. In addition, this display device 16 has D
The SC data is also displayed, and the instantaneous image information and the DSC data are stored in the personal computer 14.

A heater 8 for preventing dew condensation is arranged around the heating furnace cover 5, and the heater 8 for preventing dew condensation is driven and controlled by a driver 17 under the control of a personal computer 14. In the space formed between the heating furnace cover 5 and the heating furnace 1 and above the heating furnace cover 5, the tips of the purge gas supply pipes 9a and 9b are opened. Each of these purge gas supply pipes 9a and 9b is
The base end thereof is connected to a cylinder of a purge gas such as a nitrogen gas.
A dry purge gas is supplied to the space between the heating furnace 1 and the heating furnace cover 5 and above the heating furnace cover 5 through a and 9b. Here, one purge gas supply pipe 9a penetrates through the through-hole 5b formed in the side wall of the heating furnace cover 5 and enters the inside of the heating furnace cover 5, and its tip is located in the immediate vicinity of the lid 1b of the heating furnace 1. To open in a substantially horizontal direction, whereby the purge gas is supplied to the upper surface of the lid 1b of the heating furnace 1,
It flows between the lower surfaces of the transparent windows 5a of the heating furnace cover 5. Further, the tip of the other purge gas supply pipe 9b opens substantially horizontally above the heating furnace cover 5 so that the purge gas flows along the upper surface of the transparent window 5a of the heating furnace cover 5.

The dew condensation preventing heater 8 and the purge gas supply pipes 9a and 9b are used when a refrigerant such as liquid nitrogen is stored in the refrigerant tank 4 and measurement is performed at room temperature or lower. Dew condensation and frost adhesion to the transparent window 5a of the body 1b and the heating furnace cover 5 are prevented.

That is, by driving the dew condensation preventing heater 8, the entire temperature of the heating furnace cover 5 rises, and at the same time, only the surface temperature of the heating furnace 1 passes through the space between the heating furnace cover 5 and the heating furnace 1. Rises, and in parallel with this, heating furnace 1
A purge gas such as dry nitrogen gas is flowed through the purge gas supply pipes 9a and 9b to the upper surface of the lid 1b and the upper and lower surfaces of the transparent window 5a of the heating furnace cover 5, thereby lowering the minimum temperature of the heating furnace 1. The lid 1b of the heating furnace 1 while keeping it low
And dew condensation and frost adhesion to the surface of the transparent window 5a of the heating furnace cover 5 can be reliably prevented.

Therefore, according to the above-described embodiment of the present invention, the state of the measurement sample S in the heating furnace 1 can be photographed by the CCD camera 22 through the stereoscopic microscope 21 even at the time of measurement at room temperature or lower. In addition, the video and the DSC data can be displayed together on the display device 16.

In the above embodiment, the stereoscopic microscope 21 and the CCD are placed just above the transparent window 5a of the heating furnace cover 5.
Although the magnifying imaging means mainly including the camera 22 is arranged,
Other imaging means may be provided instead of the CD camera 22,
In addition to storing the imaging results as digital information,
It can also be configured to record on a video tape.

In the present invention, it is not always necessary to provide the above-mentioned image pickup means, and the transparent window 5a and the lid 1b
May be observed with the naked eye through the camera, or only a stereoscopic microscope may be provided so that an enlarged image can be observed.

[0025]

As described above, according to the present invention, the lid for closing the upper end of the heating furnace of the thermal analyzer and at least a part of the heating furnace cover located above the lid are formed of a transparent material and heated. Obtain visibility inside the furnace, and supply a purge gas such as dry nitrogen gas to each transparent material, and
Since the vicinity of the heating furnace is heated by a heater for preventing dew condensation, even during thermal analysis in a low temperature range below room temperature, it is ensured that condensation and frost adhere to the heating furnace and the transparent body of the heating furnace cover. The state of the sample in the heating furnace can be observed at any time via each transparent body.

Further, if the microscope and the camera are used to obtain an enlarged image of the sample in the heating furnace through the above-mentioned transparent bodies in which measures for preventing the formation of condensation and frost are taken, And thermal analysis data such as DSC signals can be recorded in association with each other, which can be an extremely effective tool for thermal analysis of a sample.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention, in which a schematic diagram showing a schematic mechanical configuration and a block diagram showing an electrical configuration are shown together.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating furnace 1a Heating furnace main body 1b Lid (made of quartz glass) 2 Heating heater 3 Heat transfer plate 4 Refrigerant tank 5 Heating furnace cover 5a Transparent window (made of quartz glass) 5b Through hole 6 Temperature sensor 7 DSC sensor 8 Dew condensation prevention Heater 11 temperature control circuit 12 measurement circuit 13 interface 14 personal computer 15 image processing board 16 display device 17 driver 21 stereo microscope 22 CCD camera

Claims (2)

[Claims] 1. A heating furnace for containing and heating a sample and a reference sample, a heating furnace cover placed over the heating furnace, and a heating furnace cover disposed in the heating furnace, wherein the sample and the reference sample A thermal analysis apparatus comprising a sensor for detecting information relating to a temperature difference, and a cooling means for cooling the heating furnace so as to enable measurement in a temperature range equal to or lower than room temperature, wherein a lid for closing an upper end of the heating furnace At least an area of the body;
At least a part of the heating furnace cover immediately above the area is formed of a transparent body, and a heater for heating the vicinity of the heating furnace and the heating furnace cover, and a heating furnace and a heating furnace cover. A thermal analyzer, comprising a gas supply pipe for supplying a purge gas toward a transparent body. 2. A microscope and a camera for photographing the inside of the heating furnace through the microscope are arranged above the heating furnace and the transparent body of the heating furnace or the bar, and a video signal from the camera is provided. 2. An image processing means for converting an image into an image and displaying the image on a display device.
4. The thermal analyzer according to 1.