JPH0273132A - Vacuum vessel for cooler evaluation - Google Patents

Abstract

PURPOSE:To easily quantitatively measure the cooling characteristic and to obtain data of high reliability by providing a temperature measuring means, which measures the ambient temperature of an inner tube, on the outside peripheral side surface of the inner tube. CONSTITUTION:A thermistor 3 is provided on the outside peripheral side surface of an inner tube 10, and its resistance value is measured through a conductor 6 by a terminal 9 to measure the change of the ambient temperature of the inner tube 10. Resistance values of thermistors 1 and 3 to temperature are preliminarily measured to obtain temperature correction data before thermistors 1 and 2 are packaged in a vessel. The DC current flowing from an external power source to a heating body 2 is varied to change the heat load, and the resistance value of the thermistor 1 is measured, and the cooling temperature in a cooling part 13 of the inner tube 10 is measured by this resistance value. Simultaneously, the gradient of the ambient temperature of the inner tube 10 is obtained by the thermistor 3. The change of the quantity of heat transmitted from the outside peripheral surface of the inner tube 11 or terminals 7 to 9 which is obtained from this temperature gradient is taken into consideration of calculation of the measured value of the cooling temperature of the cooling part 13, thereby quantitatively obtaining the characteristic of cooling temperature to heat load for a specific gas flow rate in a cooler 14.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vacuum vessel for evaluating a cooler, and more particularly to a vacuum vessel for evaluating a cooler used to evaluate the cooling capacity of a cooler using the Joule-Thomson effect.

Conventionally, in this type of vacuum container for evaluating coolers, the second
As shown in the figure, an inner tube 10 into which a cooler 14 using the Joule-Thomson effect is inserted is connected to an outer tube 1 by a flange 12.
1, and there is a vacuum between the inner tube 10 and the outer tube 11.

Conductive wires 4 and 5 are provided at the bottom of the outer periphery (cooling section 13) of the inner tube 10, respectively.
A thermistor 1 and a heating element 2 are provided, which are electrically connected to a terminal 7.8 provided on the outer tube 11 via a thermistor 1 and a heating element 2.

When evaluating the cooling capacity of the cooler 14, the cooler 14
The nozzle 15 at the tip is inserted close to one closed end inside the inner tube 10, and high pressure gas is supplied from the high pressure gas cylinder 17 to the cooler 14 through the pipe 16.

The high-pressure gas supplied from the high-pressure gas cylinder 17 and ejected from the nozzle 15 at the tip of the cooler 14 is liquefied by the Joule-Thomson effect (insulated light B) in the cooler 14, and the cooling section 13 of the inner tube 10 liquefies this high-pressure gas. The surrounding heat is absorbed and cooled.

When nitrogen gas is used as a cooling medium, the liquefaction point of nitrogen gas is at an absolute temperature of 77, so the cooling part 13 of the inner tube 10
is cooled to about 77K.

A resistor is used for the heating element 2 provided in the cooling section 13 of the inner tube 10. When direct current is applied to this heating element 2 from an external power source (not shown) through a terminal 8 electrically connected by a conductor 5, Joule heat is generated in the heating element 2. By varying this, the heat load generated from the heating element 2 can be controlled.

Since the thermistor 1 has a characteristic that its resistance value changes over a wide range depending on the temperature, the cooling capacity of the cooler 14 is measured using this characteristic.

That is, when the cooling part 13 of the inner tube 10 is being cooled by the cooler 14, the resistance value of the thermistor 1 is measured by the terminal 7 while varying the heat load generated from the heating element 2, and the inner tube is cooled. The temperature of the cooling unit 13 of the cooling unit 10 is measured to measure the cooling capacity of the cooler 14.

However, in such a conventional vacuum container for cooler evaluation, in addition to the heat load on the heating element 2, there is also a heat load on the outer tube 11.
There is an amount of heat flowing in from the outer peripheral surface of the terminal 7.8,
Since the amount of heat inflow varies depending on the size and shape of the container, as well as the environmental temperature, the amount of Fry Ostara l-(
It is difficult to quantitatively measure cooling characteristics using parameters such as the gas flow rate of the cooler 14), and the reliability of data on cooling characteristics (heat load vs. cooling temperature, heat load vs. gas flow rate, etc.) is low. be.

The present invention was made in order to eliminate the drawbacks of the conventional ones as described above, and it is possible to easily perform quantitative measurement of cooling characteristics and obtain highly reliable data on cooling characteristics. The purpose is to provide a vacuum container for evaluating coolers.

1. The vacuum container for evaluating a cooler according to the present invention is a vacuum container for evaluating a cooler that measures the cooling capacity of a cooler inserted into an inner tube, and the temperature at which the ambient temperature of the inner tube is measured. A measuring means is provided on the outer circumferential side of the inner tube.

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a configuration diagram showing the configuration of an embodiment of the present invention.
In the figure, the vacuum container for evaluating a cooler according to an embodiment of the present invention has the same structure as the conventional vacuum container for evaluating a cooler shown in FIG. Identical parts are given the same reference numerals. Further, the operations of these same parts are also the same.

The thermistor 3 is provided on the outer peripheral side of the inner tube 10,
By measuring the resistance value of the thermistor 3 from the terminal 9 via the conductor 6, changes in the ambient temperature of the inner tube 10 are measured.

In addition, before mounting thermistor 1 and thermistor 3 in the container, the thermistor resistance value with respect to temperature is measured in advance,
Obtain temperature calibration data.

The resistance value of the thermistor 1 is measured by varying the direct current flowing through the heating element 2 from an external power source (not shown) to change the heat load.
The cooling temperature in the cooling section 13 of the inner tube 10 is measured from the resistance value of the thermistor 1.

At the same time, by measuring the resistance value of the thermistor 3, changes in the ambient temperature of the inner tube 10 are measured, and the temperature gradient around the inner tube 10 is determined.

The change in the amount of heat flowing from the outer peripheral surface of the outer tube 11 or the terminals 7 to 9 obtained from this temperature gradient is reflected in the cooling section 1 of the inner tube 10.
By taking into account the measurements of the cooling temperature at 3, the characteristic of heat load versus cooling temperature for a particular gas flow rate in the cooler 14 is obtained in a formulaic manner.

In this way, the thermistor 3 for measuring the amount of heat flowing from the outer peripheral surface of the outer tube 11 or the terminals 7 to 9 is connected to the inner tube 10.
By installing it on the outer peripheral side of the container, quantitative measurements of cooling characteristics, which have been difficult to measure due to the instability of the amount of heat inflow due to the dimensions and shape of the container and the environmental temperature, can be easily performed. Can be done.

Furthermore, the temperature gradient obtained by measuring the resistance value of the thermistor 3 can be used to calibrate the measured value of the cooling temperature in the cooling section 13 of the inner tube 10 obtained by measuring the resistance value of the thermistor 1. Data on cooling characteristics can be obtained.

Incidentally, in one embodiment of the present invention, the inner tube 10 is
Although the change in the ambient temperature of the inner tube 10 is measured, the change in the ambient temperature of the inner tube 10 may be measured using other temperature measuring instruments, and the present invention is not limited thereto.

As explained above, the present invention enables quantitative measurement of cooling characteristics by measuring the outer peripheral temperature of the inner tube into which the cooler is inserted in order to measure the cooling capacity of the cooler. This has the advantage that it is possible to easily carry out the process, and to obtain highly reliable data on cooling characteristics.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the structure of an embodiment of the present invention, and FIG. 2 is a block diagram showing the structure of a conventional example. Explanation of symbols of main parts 13...Thermistor 2...Heating elements 4-6...Conductors 7-9...Terminal 10... Inner pipe 11...Outer pipe 14...Cooler

Claims (1)

[Claims] (1) A vacuum container for evaluating a cooler that measures the cooling capacity of a cooler inserted into an inner tube, wherein temperature measuring means for measuring the ambient temperature of the inner tube is provided on the outer peripheral side of the inner tube. A vacuum container for evaluating coolers.