JP4233372B2 - Ultra-low temperature calibration method and ultra-low temperature calibration device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a temperature calibration method and a temperature calibration apparatus, and more particularly to an ultra-low temperature calibration method and calibration apparatus using a portable apparatus.
[0002]
[Prior art]
FIG. 3 is a general usage example of a temperature sensor for ultra-low temperature. For example, the temperature sensor 1 for an ultra-low temperature composed of a T-type thermocouple can set the internal temperature to -80 ° C. or less, for example, the temperature sensor of the freezer 2 to measure the internal temperature of the freezer 2 for storing cultured tissue It is attached to the attachment part 3. Then, the measurement signal of the ultra-low temperature sensor 1 is output to the paperless recorder 4, the chart recorder 5, the monitoring recording device 6 using a personal computer, or the like according to the system configuration.
[0003]
In order to guarantee and prove that the measured values of such thermometers and temperature measuring devices maintain the specified accuracy, calibration should be performed periodically to clarify the correspondence between each measured value and the corrected value. I have to leave.
[0004]
Therefore, in general, for example, as shown in FIG. 4, the temperature sensor 1 to be calibrated is inserted into a temperature-controlled comparison thermostat 8 together with a standard temperature sensor 7 made of a platinum resistance thermometer that has been calibrated in advance. The actual temperature in the comparative thermostat 8 is measured, and the measured value of the standard temperature sensor 7 digitally displayed on the digital thermometer 9 used as a display device is digitally displayed on the digital thermometer 10 used as a display device as a standard. The actual temperature calibration for comparing and calibrating the measured value of the calibration temperature sensor 1 is performed. Here, as the standard temperature sensor, a sensor that is calibrated one after another at a higher measurement level and that is guaranteed “traceability” based on JIS 8103, which establishes a route leading to national and international standards, is used.
[0005]
By the way, as the user of the temperature sensor 1 to be calibrated, the calibration of the temperature sensor 1 to be calibrated is the place where the temperature sensor 1 to be calibrated is installed in order to maintain the continuous operation of the temperature measurement target device such as a freezer. Or it is desirable to carry it in the vicinity.
[0006]
However, since the temperature chamber is an air tank type, the temperature setting range cannot be set to −30 ° C. or lower in the conventional portable comparative thermostat. Also, the air tank type temperature tank has a large thermal time constant, and it takes one hour or more to reach the set temperature, so that the working efficiency is poor.
[0007]
At present, devices that are commercialized as comparative thermostats that can be set to −30 ° C. or less have a weight of 100 kg or more and a power source of 200 VAC. Is not suitable.
[0008]
Therefore, at present, actual temperature calibration in the ultra-low temperature range (−80 ° C. or lower) cannot be performed at the place where the temperature sensor 1 to be calibrated is installed.
[0009]
Therefore, as shown in the flowchart of FIG. 5, the calibration operator such as the user or the manufacturer of the temperature sensor to be calibrated removes the temperature sensor to be calibrated from the temperature measurement target device (SP1), and replaces the temperature sensor with the alternative temperature sensor. Install (SP2). Then, after packing the removed temperature sensor to be calibrated (SP3), it is shipped to the calibration company by transportation (SP4). The calibration operator unpacks (SP5) and performs the actual temperature calibration with the temperature sensor itself (SP6).
[0010]
When the calibration company completes the actual temperature calibration, it packs the temperature sensor to be calibrated (SP7), and sends it to the user by transportation (SP8). The user unpacks (SP9), removes the alternative temperature sensor from the temperature measurement target device (SP10), and attaches the temperature sensor to be calibrated to the temperature measurement target device (SP1.1). In addition, about the display apparatus to which a to-be-calibrated temperature sensor is connected, on-site calibration is performed by inputting a simulated electric signal via the signal cable from the site | part which removed the to-be-calibrated temperature sensor.
[0011]
[Patent Document 1]
JP 2000-205973 A
[0012]
Patent Document 1 discloses a method and apparatus for calibrating a thermocouple for temperature measurement of a cryogenic liquid using an actual liquid such as liquid oxygen or liquid nitrogen.
[0013]
However, Patent Document 1 does not suggest that calibration is performed using a portable comparative thermostat as in the present invention.
[0014]
[Problems to be solved by the invention]
About the temperature sensor to be calibrated In the conventional method of sending the temperature sensor to be calibrated to the calibration company's factory each time calibration at -30 ° C or lower, the cost of having an alternative temperature sensor, the temperature of the temperature sensor The number of man-hours for removing and installing the device to be measured, the temperature sensor packing, shipping and unpacking, and the man-hours for management are increased, increasing the user's cost burden and installing the calibrated temperature sensor to be installed by the user. It is not uncommon for it to take almost a month to return to the site.
[0015]
In the method of sending the temperature sensor to be calibrated to the factory of the calibration company, the actual temperature cannot be calibrated as a whole ultra low temperature measuring device including the temperature sensor to be calibrated, the signal cable, and the display device. Can not prove.
[0016]
The present invention pays attention to these problems, and the purpose thereof is the actual temperature of the entire ultra-low temperature measuring device including the temperature sensor to be calibrated, the signal cable, and the display device at or near the installation location of the temperature sensor to be calibrated. An object of the present invention is to provide an ultra-low temperature calibration method and an ultra-low temperature calibration apparatus capable of performing calibration.
[0017]
[Means for Solving the Problems]
The invention of claim 1 which achieves such an object,
A cryogenic calibration device that is configured to be movable at or near the place where the temperature sensor to be calibrated connected to the display device via the signal cable is installed, and is connected to the display device connected via the signal cable. By inserting the calibration temperature sensor together with the standard temperature sensor into the ultra-low temperature calibration device ,
As the ultra-low temperature calibration device,
At least two refrigerators that can be individually controlled, and at least two that are individually cooled by the refrigerator and into which coolant is injected and the temperature sensor to be calibrated and the standard temperature sensor are inserted to the same depth according to the guide A tubular liquid tank, at least two temperature controllers that individually control the refrigerator so that the inside of the tubular liquid tank has a desired ultra-low temperature, and an opening of the tubular liquid tank. The lid includes a lid integrated with the guide for positioning the insertion depth of the temperature sensor to be calibrated and the standard temperature sensor, and a moving wheel attached to the bottom of the apparatus .
[0018]
The invention of claim 2 is the ultra-low temperature calibration method according to claim 1,
The actual temperature calibration of the temperature sensor to be calibrated is performed in one tubular liquid tank of the ultra-low temperature calibration apparatus, and the temperature sensor is pre-cooled in the other tubular liquid tank .
[0019]
The invention of claim 3 is the ultra-low temperature calibration method of claim 1 ,
Two-point calibration of the temperature sensor to be calibrated is performed by setting one tubular liquid tank and the other tubular liquid tank of the ultra-low temperature calibration apparatus to different calibration temperatures .
[0020]
The invention of claim 4 is the ultra-low temperature calibration method according to any one of claims 1 to 3 , wherein the solution bottle to be injected into the tubular liquid tank of the ultra-low temperature calibration device is pre-cooled in advance. To do.
[0021]
The invention of claim 5
At least two refrigerators that can be controlled individually;
At least two tubular liquid tanks that are individually cooled by the refrigerator and into which the coolant is injected and into which the temperature sensor to be calibrated and the standard temperature sensor are inserted to the same depth according to the guide;
At least two systems of temperature controllers that individually control the refrigerator so that the inside of these tubular liquid tanks has a desired ultra-low temperature;
A lid in which the guide for positioning the insertion depth of the temperature sensor to be calibrated and the standard temperature sensor is integrated with the lid;
Moving wheels attached to the bottom of the device,
It is an ultra-low temperature calibration device characterized by comprising:
[0022]
The invention of claim 6 is the ultra-low temperature calibration apparatus according to claim 5,
A cooling liquid outlet is provided at the bottom of the tubular liquid tank.
[0026]
As a result, it is possible to realize an ultra-low temperature calibration method and an ultra-low temperature calibration device that can perform actual temperature calibration as the entire ultra-low temperature measuring device including the temperature sensor to be calibrated, the signal cable, and the display device at or near the place where the temperature sensor is calibrated. it can.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on exemplary embodiments of the present invention with reference to the drawings. FIG. 1 is a structural conceptual diagram showing an embodiment of the present invention, and the same reference numerals are given to the parts common to FIGS. In FIG. 1, an ultra-low temperature calibration apparatus 100 is configured to be movable as shown in FIG. 2, and is transported to or near the place where the temperature sensor 1 to be calibrated is installed to perform ultra-low temperature calibration.
[0028]
In FIG. 2, two individually controllable refrigerators 1 and 10 are provided inside the ultra-low temperature calibration apparatus 100, and the tubular liquid tanks 121 and 122 are individually set to, for example, a temperature lower limit value of about −150 ° C. Cooling. The tube-shaped liquid tanks 121 and 122 are provided so as to open at the top of the ultra-low temperature calibration apparatus 100, and a commercially available alcohol-based coolant is injected therein, and the opening is configured to be detachable. Covered lids 131 and 132 are attached. Note that the opening diameter of the tubular liquid tanks 121 and 122 is, for example, 30 mm, and the depth is 340 mm.
[0029]
Guide bodies 141 and 142 for inserting the temperature sensor 1 to be calibrated and the standard temperature sensor 7 to the same depth in the tubular liquid tanks 121 and 122 are integrated with the lids 131 and 132, respectively. At the bottom of the tubular liquid tanks 121 and 122, there are provided outlets 151 and 152 for collecting the coolant.
[0030]
The temperature controllers 161 and 162 that perform temperature display and ON / OFF control or PID control with an accuracy of, for example, an error of 0.1 ° C. for the refrigerant circulation valves of the refrigerators 1 and 10 according to the setting are the ultra-low temperature calibration device 100. It is provided so that setting operation can be performed on the front side. The display lamps 171 and 172 and the power switches 181 and 182 are provided in the vicinity of the temperature controllers 161 and 162.
[0031]
In the vicinity of the four corners of the bottom surface of the ultra-low temperature calibration apparatus 100, moving wheels 190 are provided, and handles 200 are provided on both side surfaces. The ultra-low temperature calibration apparatus 100 is configured to be driven with AC 100V. The ultra-low temperature calibration apparatus 100 configured as described above has a weight of about 45 kg and can be transported and moved by two people. The overall size of the ultra-low temperature calibration apparatus 100 is, for example, 550 mm wide, 500 mm high, and 470 mm deep.
[0032]
In FIG. 1 again, the ultra-low temperature calibration of the temperature sensor 1 to be calibrated is performed by using the temperature sensor 1 to be calibrated connected to the display device via a signal cable together with the standard temperature sensor 7 in the tubular liquid tanks 121 and 122 of the ultra-low temperature calibration device 100. Insert it into either one and perform the actual temperature calibration. In the example of FIG. 1, the temperature sensor 1 to be calibrated inserted into the freezer 2 so as to measure the internal temperature of the freezer 2 is inserted into the tubular liquid tank 121 in a state where it is connected to the chart recorder 5 used as a display device. ing.
[0033]
With such a system configuration, the temperature in the ultra-low temperature calibration apparatus 100 has been proven to be traceable by the combination of the standard temperature sensor 1 and the standard digital thermometer 9 used as a display device. By comparing the temperature indication value of the above and the temperature indication value of the chart recorder 5, it is possible to prove the traceability of the entire ultra-low temperature measuring apparatus including the temperature sensor 1 to be calibrated, the signal cable, and the chart recorder 5 as a display device. .
[0034]
Here, since the ultra-low temperature calibration apparatus 100 is provided with two tubular liquid tanks 121 and 122, the other tubular liquid tank 122 is used for pre-cooling a plurality of temperature sensors or performing two-point calibration. By setting the calibration temperature at the other point, a more efficient calibration operation can be performed.
[0035]
By using the ultra-low temperature calibration device 100 that can be moved and transported in this way, the traceability of the entire ultra-low temperature measurement device including the temperature sensor, signal cable, and display device, which could not be performed in the field by the conventional method, is proved in a short time. it can. Specifically, in the case of the conventional calibration company factory taking over, what took one month can be implemented in one day in the present invention.
[0036]
Since the temperature tank of the ultra-low temperature calibration apparatus 100 is changed from the air tank to the tubular liquid tanks 121 and 122, the solution bottle to be injected into the tubular liquid tanks 121 and 122 can be precooled with dry ice or the like in advance. And the temperature ON / OFF control by the temperature controllers 161 and 162, the target temperature arrival time is about 15 minutes, which is less than 1/5 that of the conventional air tank, and further by PID control. By realizing temperature stabilization, work efficiency is dramatically improved.
[0037]
In order to operate the refrigeration equipment during the conventional calibration company factory take-off calibration period, an alternative temperature sensor is required. However, in the present invention, there is no need for the purchase maintenance maintenance cost, the alternative product installation / removal cost, etc. The cost will be greatly reduced.
As described above, the work efficiency is improved by 5 times or more, so that the cost is greatly reduced in terms of work man-hours.
[0038]
Furthermore, it is a technology that can meet the demands of ultra-low temperature control in recent pharmaceutical business related (biotechnology, GMP, GLP) and food business related (HACCP). It is.
[0039]
The ultra-low temperature calibration device 100 can also be used as a sample constant temperature cooling device. That is, since the internal temperature of the tubular liquid tanks 121 and 122 can be controlled at ± 0.1 ° C., for example, a test tube containing a sample is simply placed in the tubular liquid tanks 121 and 122 with the lids 131 and 132 opened. Thus, it can be cooled easily and accurately to the lower temperature limit of about -150 ° C.
[0040]
【The invention's effect】
As described above, according to the present invention, an ultra-low temperature calibration method capable of performing actual temperature calibration of the entire ultra-low temperature measuring device including the temperature sensor to be calibrated, the signal cable, and the display device at or near the installation location of the temperature sensor to be calibrated. In addition, it is possible to realize an ultra-low temperature calibration device and meet various ultra-low temperature control requirements represented by the pharmaceutical business and food business field.
[Brief description of the drawings]
FIG. 1 is a configuration conceptual diagram showing an embodiment of the present invention.
FIG. 2 is a diagram illustrating the configuration of an ultra-low temperature calibration apparatus 100 used in FIG.
FIG. 3 is a general usage example of a temperature sensor for ultra-low temperature.
FIG. 4 is an explanatory diagram showing a conventional temperature calibration example.
FIG. 5 is a flowchart showing a procedure of a conventional temperature calibration example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Temperature sensor to be calibrated 2 Freezer 3 Temperature sensor attachment part 4 Paperless recorder 5 Clock phase detection 6 Monitoring recording device 7 Standard temperature sensor 9 Digital thermometer 100 Cryogenic calibration device 1 · 10 Refrigerator 121 · 122 Tube type liquid tank 131 · 132 Lids 141 and 142 Guide bodies 151 and 152 Extraction ports 161 and 162 Temperature controllers 171 and 172 Indicator lamps 181 and 182 Power switch 190 Moving wheel 200 Handle

Claims (6)

A cryogenic calibration device that is configured to be movable at or near the place where the temperature sensor to be calibrated connected to the display device via the signal cable is installed, and is connected to the display device connected via the signal cable. By inserting the calibration temperature sensor together with the standard temperature sensor into the ultra-low temperature calibration device ,
As the ultra-low temperature calibration device,
At least two refrigerators that can be individually controlled, and at least two that are individually cooled by the refrigerator and into which coolant is injected and the temperature sensor to be calibrated and the standard temperature sensor are inserted to the same depth according to the guide A tubular liquid tank, at least two temperature controllers that individually control the refrigerator so that the inside of the tubular liquid tank has a desired ultra-low temperature, and an opening of the tubular liquid tank. An ultra-low temperature characterized by using a lid integrated with the guide for positioning the insertion depth of the temperature sensor to be calibrated and the standard temperature sensor, and a moving wheel attached to the bottom of the apparatus. Calibration method. 2. The cryogenic calibration method according to claim 1, wherein an actual temperature calibration of the temperature sensor to be calibrated is performed in one tubular liquid tank of the ultra-low temperature calibration apparatus, and the temperature sensor is pre-cooled in the other tubular liquid tank. . 2. The ultra-low temperature calibration method according to claim 1, wherein the temperature sensor to be calibrated is subjected to two-point calibration by setting one tubular liquid tank and the other tubular liquid tank of the ultra-low temperature calibration apparatus to different calibration temperatures . The ultra-low temperature calibration method according to any one of claims 1 to 3, wherein a solution bottle to be injected into a tubular liquid tank of the ultra-low temperature calibration device is pre-cooled in advance . At least two refrigerators that can be controlled individually;
At least two tubular liquid tanks that are individually cooled by the refrigerator and into which the coolant is injected and into which the temperature sensor to be calibrated and the standard temperature sensor are inserted to the same depth according to the guide;
At least two systems of temperature controllers for individually controlling the refrigerators so that the inside of these tubular liquid tanks has a desired ultra-low temperature;
A lid in which the guide for positioning the insertion depth of the temperature sensor to be calibrated and the standard temperature sensor is integrated with the lid;
Moving wheels attached to the bottom of the device,
An ultra-low temperature calibration device characterized by comprising 6. The cryogenic calibration apparatus according to claim 5, wherein a cooling liquid outlet is provided at the bottom of the tubular liquid tank.

Images