JPH0251288A - Sample temperature controller - Google Patents

Abstract

PURPOSE:To make it possible to easily exchange a sample without disjointing a heat insulating vacuum vessel by opening one end of a sample chamber to the air side, and installing a sample introduction mechanism to seal this opening part airtightly from the air side and a gas charging mechanism. CONSTITUTION:After removing a cover, and setting a sample 12 to a sample supporter 11, and then wiring a measuring wire, the sample is inserted into a sample chamber 8, which is made air tight by fastening a clamp 9. Next, after exhausting the airinside the sample chamber into vacuum, helium gas is introduced by a gas charging mechanism 23 connected to a valve 23, and then the valve 13 is closed. A small cooler driving source is turned on, and with the temperature drop of the second stage the temperature of a copper block 7 is also lowered. Since noncondensing helium gas is charged into the sample chamber 8, the region at the same height as the copper block 7 is made almost uniform temperature, and the sample 12 is also made almost the same temperature as the copper block 7. For the exchange of the sample 12, in the condition that the temperature of the sample returned to the room temperature, the clamp 9 is removed and the inside of the sample 8 is made the atmospheric pressure, and the sample supporter 11 is pulled out, and the sample is exchanged.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sample temperature control device that uses a compact refrigerator and a heater to lower the temperature of a sample to below room temperature. [Prior Art] Conventional sample temperature control device One type of control device is one using a cryogen as a cold source, the temperature control by changing the sample position as described in Japanese Patent Application Laid-Open No. 151482/1982, and one using a refrigerator as described in Nikkei Mechanical June 15, 1987. There is a device such as that shown in FIG. 1 of the Japanese issue, pages 58 to 60'M.

[Problem to be solved by the invention]

In the above-mentioned conventional technology, liquid helium is used as a cryogen to cool the sample to -200° C. or lower, but a small refrigerator is also used. In the former case, there was a problem that the cryogen was not freely available, and in the latter case, each time a sample was to be replaced, the insulated vacuum chamber containing the sample chamber had to be dismantled, which required time and effort.

An object of the present invention is to easily exchange a sample in a sample temperature control device using a small refrigerator without dismantling the adiabatic vacuum chamber.

[Means to solve the problem]

In order to achieve the above object, one end of the sample chamber is opened to the atmosphere, and a sample introduction mechanism and a gas sealing mechanism are provided to airtightly isolate this opening from the atmosphere.

[Effect]

The sample held in the sample introduction mechanism is set to be introduced to the sample chamber via the above-mentioned interval L1. Further, the inside of the sample chamber is filled with non-condensable gas by a gas filling mechanism, and the temperature inside the sample chamber is made uniform. The sample chamber is controlled to an arbitrary temperature by a small refrigerator and heater attached to the outside.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 1 is the head of a small refrigerator that operates on the Gifford cycle or Solvay cycle, and has a built-in motor and other components.
It is attached to the pedestal 2. 3 and 4 are the cold generation sections of the small refrigerator, and the first section has a temperature of around 70, respectively.
This will be referred to as the second stage, which occurs before and after stage 15.

In the second stage, a copper block 7 with a heater 5 and a temperature sensor 6 is mounted in thermal contact. A sample chamber made of thin stainless steel is inserted into this copper block 7, and its upper end can be opened to the atmosphere by a clamp 9. A sample support 11 is attached to the lid 10, and a sample 12 is set on the copper block 7. 1
3 is a valve on the piping that communicates with the sample chamber, and 14 is a meter led out from the sample chamber. This is the terminal for the 1Ill line. copper block 7
The second stage 4 is substantially surrounded by a radiation shield 15 made of copper. Further, the outside of the first stage 3 and the radiation shield 15 are surrounded by vacuum containers 16a and 16b, which are evacuated by a valve 17 and sealed.

The operation of this embodiment will be explained below. First, vacuum container 16
The inside of a and 16b is a vacuum exhaust system 18 connected to a valve 17.
After exhausting the air, valve 17 is closed. A gas pipe 19 is drawn out from the head 1 of the small refrigerator, and is connected to a small refrigerator drive source 20 mainly consisting of a compressor.

The heater 5 and the temperature sensor 6 are connected to a temperature regulator 22 via a terminal 21. After removing the lid 10, setting the sample 12 on the sample support 11, and wiring the measurement wire, open the sample chamber 8.
, and tighten the clamp 9 to make it airtight. next,
After the sample chamber is evacuated by a gas filling mechanism 23 connected to the valve 13, helium gas is introduced, and the valve 13 is closed. When the small refrigerator drive source 20 is started, the temperature of the second stage decreases, and the temperature of the copper block 7 also decreases accordingly.

Thermal contact is established between the copper block 7 and the sample chamber 8 using solder, grease, or the like. Since the sample chamber 8 is filled with non-condensable helium gas, due to heat conduction and convection, the area at the same height as the copper block 7 has a temperature of approximately -, and the sample 12 is also approximately at the same height as the copper block. The temperature will be the same as 7. Temperature regulator 22 and small refrigerator drive source 20
can be used to freely set the temperature of the sample 12.

The measurement data is recorded and processed in the data processing device 24.

The sample 12 can be replaced by removing the clamp 9 after the sample temperature has returned to room temperature, making the sample chamber 8 atmospheric pressure, pulling the sample support 11 out, and replacing the sample 12.

Next, another embodiment will be explained with reference to FIG. Figure 2 shows
This is another example of the area around the sample chamber 8 of the apparatus shown in FIG. 1. A flange 16 is further provided on the top of the vacuum container 16a.
Place c, which is a boat: 30 a, 30 b
, 30 c. The sample chamber 8 is inserted into this boat 30a, and vacuum tightness is ensured by a seal 31 using an O-ring. Further, an adapter 33 is attached to the upper end of the sample chamber 8 via a seal 32, and a valve 13 is connected to the adapter 33. A plurality of shield plates 34 and a thermal anchor 35 are attached to the sample support 11 .

The sample 12 and the measurement line are supported by a thermal anchor 35. Boats 30b and 30c have piping 36a and 36b.
is connected and communicates with a tube 37 wound around the copper block 7.

A sliding seal 3 connects the boat 30a and the sample chamber 8.
1, it is easy to assemble, and even if the sample chamber 8 and the copper block 7 are connected by soldering or the like, thermal deformation can be easily absorbed. The tubes 37 carry a heating or cooling medium and are used to achieve temperature levels that cannot be achieved with the second stage 4 and heater 5 of the compact refrigerator. For example, if liquid helium is used as a refrigerant, the temperature can be lowered to around 4.

With such a sample chamber configuration, for example, the superconducting critical temperature of a perovskite superconducting material can be measured by an electrical resistance method or an alternating current magnetic susceptibility measurement method.

Furthermore, if a vacuum container for enclosing a sample is further provided in the sample chamber, thermal measurements such as specific heat and thermal conductivity are also possible.

Furthermore, if the copper block 7 is provided with an airtight window, optical measurement is also possible.

FIG. 3 shows another embodiment of the present invention, which is a sample temperature control device suitable for measuring the coefficient of thermal expansion of a material. Only the vicinity of the sample chamber 8 is shown. Inside the sample chamber 8 is an outer tube 40 made of quartz glass! #4] are inserted concentrically to close the lower end of the outer tube 40, the cylindrical sample 12 is placed inside the copper cylinder 42, and the lower end of the rod 41 is placed. adapter 33
Inside, a displacement sensor 44 is fixed to a column 43 supported at the upper end of the outer tube 40, and the tip of the sensor lightly presses the support 41. Between the copper block 7 and the second stage 4 of the small refrigerator, there are a lower plate 45 and an upper plate 46 having good thermal conductivity and having protrusions.
are separated and engaged, airtightly connected by a cylinder 47 of low thermal conductivity such as stainless steel, and a pipe 48 is drawn out from inside.

According to such a configuration, the temperature of the sample can be raised to above room temperature. That is, by creating a vacuum inside the cylinder 47, the thermal contact between the lower plate 45 and the upper plate 46 is broken, and the temperature can be freely increased by the heater 5. Conversely, in order to obtain thermal contact, if helium gas is injected from the pipe 48 leading to the outside, the cold from the second stage 4 will be transferred to the copper block side by heat conduction and convection of the gas.

If it is desired to examine the influence of the magnetic field, an electromagnet 9 may be installed outside the copper block 7. In particular, in the case of an electromagnet using a superconductor, the vacuum insulation part is the vacuum vessel 16a, 1
Can be used in common with 6b and 16c.

〔Effect of the invention〕

As described above, according to the present invention, since the sample chamber can be directly opened to the atmosphere, the sample can be easily replaced.

[Brief explanation of the drawing]

FIG. 1 is an overall sectional view showing one embodiment of the present invention, FIG. 2 is a partial sectional view showing another embodiment around the sample chamber shown in FIG. 1, and FIG. 3 is the same as that shown in FIG. FIG. 6 is a partial cross-sectional view showing still another embodiment around the sample chamber shown in FIG. 4... Second stage of small refrigerator, 5... Heater,
7... Copper block, 8... Sample chamber, 11... Sample support, 12... Sample, 23... Gas filling mechanism, 3
3...Adapter, 37...Pipe, 44...Displacement sensor, 47...Cylinder.

Claims (1)

[Claims] 1. A sample temperature control device that sets the temperature of a sample using a combination of a small refrigerator and a heater, which includes a sample chamber with one end open to the atmosphere, and a sample introduction mechanism and gas airtightly attached to the opening of the sample chamber. A sample temperature control device comprising: an enclosure mechanism;