Constant temperature source, system and method for verifying magnetic surface temperature sensor

Abstract

The invention belongs to the field of magnetic surface temperature sensor calibration, and provides a constant temperature source, system and method for verifying a magnetic surface temperature sensor. The calibration device comprises a thermostatic bath and a hot plate, a working medium in a set temperature range is arranged in the thermostatic bath, and the working medium is in contact with the bottom surface of the hot plate; the hot plate has a ferromagnetic characteristic, so that the magnetic surface temperature sensor is automatically adsorbed on the upper surface of the hot plate; the hot plate is of a sunken structure and is sealed on the upper surface of the thermostatic bath; a plurality of grooves are formed in the lower surface of the hot plate, and the direction of the grooves is consistent with the flowing direction of the working medium, so that the temperature of the lower surface of the hot plate is consistent with that of the working medium in the thermostatic bath during heat balance. According to the invention, calibration of the magnetic surface temperature sensor in a full temperature range of (-30 DEG C to + 200 DEG C can be realized, and the accuracy of a calibration result of the magnetic surface temperature sensor is improved.

Description

Technical Field

[0001] The invention belongs to the field of calibration of magnetic - adsorption surface temperature sensors, and particularly relates to a constant - temperature source, a system and a method for calibrating a magnetic - adsorption surface temperature sensor. Background Technique

[0002] The statements in this part only provide background technical information related to the present invention and do not necessarily constitute prior art.

[0003] Due to the advantages of easy assembly, easy removal and firm installation, a magnetic - adsorption surface temperature sensor (such as a magnetic - adsorption platinum resistance temperature probe) can measure temperature by being adsorbed on the surface of a magnetic metal through a strong magnet, without punching or pasting on the surface of the object to be measured, protecting the integrity of the surface of the object to be measured. The magnetic - adsorption surface temperature sensor can be widely used in surface temperature tests in industrial fields such as pipe wall temperature monitoring, metal surface temperature monitoring, heating devices, and surface temperature monitoring of industrial equipment.

[0004] On the one hand, the temperature measurement range of the magnetic - adsorption surface temperature sensor is mostly in the range of (-30~+200)°C. At present, in the calibration field, according to JJG684 - 2003 "Surface Platinum Resistance Thermometer" or JJF1409 - 2013 "Surface Thermometer", the low - temperature area of the constant - temperature surface source is limited to the temperature range of (room temperature ≤ t ≤ 100)°C, making it difficult to achieve surface temperature calibration below room temperature, and the calibration process is greatly affected by human factors. On the other hand, the liquid medium in the constant - temperature bath of the existing constant - temperature source for calibrating the magnetic - adsorption surface temperature sensor may generate a vortex phenomenon, resulting in the hot plate of the constant - temperature source not reaching thermal equilibrium and affecting the accuracy of the calibration result of the magnetic - adsorption surface temperature sensor. Summary of the Invention

[0005] In order to solve the technical problems existing in the above - mentioned background technique, the present invention provides a constant - temperature source, a system and a method for calibrating a magnetic - adsorption surface temperature sensor, which can calibrate the magnetic - adsorption surface temperature sensor in the full temperature range of (-30~+200)°C, avoid the occurrence of vortex at the contact surface between the liquid and the flange, and improve the accuracy of the calibration result of the magnetic - adsorption surface temperature sensor.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The first aspect of the present invention provides a constant - temperature source for calibrating a magnetic - adsorption surface temperature sensor.

[0008] A constant - temperature source for calibrating a magnetic - adsorption surface temperature sensor includes: a constant - temperature bath and a hot plate; a working medium within the set temperature range is provided in the constant - temperature bath, and the working medium contacts the bottom surface of the hot plate; the hot plate has ferromagnetic properties so that the magnetic - adsorption surface temperature sensor is automatically adsorbed on the upper surface of the hot plate;

[0009] The hot plate has a sunken structure and is sealed on the upper surface of the constant temperature bath; several grooves are provided on the lower surface of the hot plate, and the direction of the grooves is consistent with the flow direction of the working medium to ensure that the temperature of the lower surface of the hot plate is the same as that of the working medium in the constant temperature bath at thermal equilibrium.

[0010] As an implementation manner, the grooves are V-shaped grooves.

[0011] As an implementation manner, the depth and width dimensions of the V-shaped grooves are equal.

[0012] As an implementation manner, the depth and width dimensions of the V-shaped grooves are both 12.5 mm, and the fillet radius at the peak of the V-shaped grooves is less than 25%.

[0013] As an implementation manner, a heat insulation layer is provided inside the constant temperature bath.

[0014] As an implementation manner, the material of the heat insulation layer is ceramic fiber zircon shield blanket.

[0015] The second aspect of the present invention provides a system for calibrating a magnetic adsorption type surface temperature sensor.

[0016] A system for calibrating a magnetic adsorption type surface temperature sensor includes: an industrial personal computer, a standard surface temperature sensor, a thermometer, a thermometer constant temperature box, and a constant temperature source for calibrating the magnetic adsorption type surface temperature sensor as described above;

[0017] The thermometer is arranged inside the thermometer constant temperature box, and the thermometer constant temperature box is used to continuously provide a constant temperature environment for the thermometer;

[0018] The measuring ends of the standard surface temperature sensors are all arranged on the upper surface of the hot plate, and the reference ends of the standard surface temperature sensors are connected to the measuring channels of the thermometer.

[0019] As an implementation manner, the industrial personal computer, the thermometer constant temperature box, and the constant temperature source for calibrating the magnetic adsorption type surface temperature sensor are all fixed on a lifting table frame.

[0020] The third aspect of the present invention provides a method for calibrating a magnetic adsorption type surface temperature sensor.

[0021] A method for calibrating a magnetic adsorption type surface temperature sensor uses the system for calibrating the magnetic adsorption type surface temperature sensor as described above; the method for calibrating the magnetic adsorption type surface temperature sensor includes:

[0022] Before the constant temperature bath is heated up, the magnetic adsorption type surface temperature sensor to be calibrated is adsorbed on the surface of the hot plate;

[0023] Set the constant temperature environment temperature of the thermostatic chamber of the thermometer according to the preset temperature of the reference end of the standard surface temperature sensor.

[0024] Use the measuring end of the standard surface temperature sensor to collect the temperature of the hot plate surface and transmit it to the measuring channel of the thermometer to obtain the measured value of the hot plate surface temperature.

[0025] According to the measured value of the hot plate surface temperature, the working chamber temperature of the thermostat is corrected in real time so that the surface temperature of the hot plate meets the requirements of the calibration specification.

[0026] When the surface temperature of the hot plate meets the requirements of the calibration specification, obtain the temperature value detected by the calibrated magnetic adsorption type surface temperature sensor.

[0027] As an implementation, during the process of correcting the working chamber temperature of the thermostat in real time, preset the threshold value of the difference between the standard surface temperature sensor and the thermostat temperature as the benchmark for determining the correction of the thermostat temperature.

[0028] After the standard surface temperature sensor is stable, automatically calculate the difference between its temperature and the temperature of the thermostat control sensor. If the difference does not meet the preset threshold value, automatically adjust the set temperature of the thermostat until the difference reaches the preset threshold value.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] (1) The hot plate of the present invention adopts a sunken structure and a groove design at the bottom, which can effectively increase the contact area with the liquid medium, so that the temperature of the bottom working surface of the hot plate is more consistent with the temperature of the liquid medium in the thermostat when reaching thermal equilibrium; moreover, the direction of the groove is consistent with the direction of liquid flow, avoiding the occurrence of eddy currents at the contact surface between the liquid and the flange.

[0031] (2) The present invention uses a standard temperature sensor to measure the surface temperature of the constant temperature surface source hot plate in real time, preset the threshold value of the difference between the standard surface temperature sensor and the thermostat temperature as the benchmark for determining the correction of the thermostat temperature; by automatically calculating the comparison between the difference between the temperature measured by the standard surface temperature sensor and the temperature of the thermostat control sensor and the preset threshold value, automatically adjust the set temperature of the thermostat, achieving the purpose of automatically and accurately calibrating the magnetic adsorption type surface temperature sensor.

[0032] Advantages of additional aspects of the present invention will be partly given in the following description, partly will become obvious from the following description, or will be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The specification drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0034] Figure 1 It is a schematic diagram of the constant temperature source structure for calibrating the magnetic adsorption type surface temperature sensor according to an embodiment of the present invention;

[0035] Figure 2 It is a schematic diagram of the hot plate structure according to an embodiment of the present invention;

[0036] Figure 3 It is a schematic diagram of the hot plate sealing device according to an embodiment of the present invention;

[0037] Figure 4 It is the overall drawing of the hot plate according to an embodiment of the present invention;

[0038] Figure 5 It is a schematic diagram of the bottom groove of the hot plate according to an embodiment of the present invention;

[0039] Figure 6 It is a schematic diagram of the constant temperature box structure of the thermometer according to an embodiment of the present invention;

[0040] Figure 7 It is the temperature measurement principle diagram of the standard surface temperature sensor according to an embodiment of the present invention;

[0041] Figure 8 It is the operation process of the standard thermometer constant temperature box according to an embodiment of the present invention. Detailed implementation manners

[0042] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0043] It should be noted that the following detailed descriptions are all illustrative and are intended to provide further descriptions of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0044] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0045] Embodiment 1

[0046] In one or more embodiments, as Figure 1 and Figure 2As shown in the figure, a constant temperature source 1 for calibrating a magnetic adsorption type surface temperature sensor includes: a constant temperature bath and a hot plate 12; a working medium (such as low-temperature heat-conducting oil or silicone oil, etc.) within the set temperature range is provided in the constant temperature bath, and the working medium is in contact with the bottom surface of the hot plate; the hot plate has ferromagnetic properties, so that the magnetic adsorption type surface temperature sensor is automatically adsorbed on the upper surface of the hot plate.

[0047] The hot plate 12 has a sunken structure, and the hot plate is sealed on the upper surface of the constant temperature bath; several grooves are provided on the lower surface of the hot plate 12, and the direction of the grooves is consistent with the flow direction of the working medium, so as to ensure that the temperature of the lower surface of the hot plate is the same as that of the working medium in the constant temperature bath when thermal equilibrium is reached.

[0048] In the present invention, the constant temperature bath is used as the heat source of the constant temperature surface source, and low-temperature heat-conducting oil (or silicone oil) is used as the working medium of the constant temperature bath to realize the calibration of the magnetic adsorption type surface temperature sensor in the temperature range of (-30 to 200) °C.

[0049] In the embodiment of the present invention, the hot plate is a key component of the constant temperature surface source. Its structure is a sunken structure (such as an embedded flange), and the bottom is designed with grooves, which can effectively increase the contact area with the liquid medium, so that the temperature of the bottom working surface of the hot plate is more consistent with that of the liquid medium in the constant temperature bath when thermal equilibrium is reached. The direction of the grooves is consistent with the flow direction of the liquid to avoid eddy currents at the contact surface between the liquid and the flange.

[0050] In some alternative embodiments, the working surface of the hot plate is a high-purity nickel plate. Nickel is a transitional metal element that is approximately silver-white, hard and ductile and has ferromagnetic properties. Its thermal conductivity is 90 W / [m×K], and it has good corrosion resistance, which is the optimal choice for the material of the hot plate of the constant temperature surface source. During the calibration process, the magnetic adsorption type surface temperature sensor can be automatically adsorbed on the surface of the hot plate, and the close contact between the sensor and the surface of the hot plate can be achieved without any external force.

[0051] As Figure 3 shown, a sealing device for the hot plate of the constant temperature surface source is made of polytetrafluoroethylene, and polytetrafluoroethylene has excellent chemical corrosion resistance and heat resistance.

[0052] In the embodiment of the present invention, as Figure 4 and Figure 5 shown, the groove is a V-shaped groove. Among them, the depth and width dimensions of the V-shaped groove are equal. In this way, the uniformity and volatility of the temperature field of the constant temperature bath can be stably maintained at ≤0.1 °C for a long time, and a uniform and stable test temperature field can be provided for the surface temperature calibration device.

[0053] When the depth and width dimensions of the V-shaped groove are both 12.5 mm and the fillet radius at the peak of the V-shaped groove is less than 25%, it has a good drag reduction effect, and the maximum drag reduction rate can reach 6.6%. The secondary vortex generated at the peak of the groove is the fundamental reason for the drag reduction of the groove surface, and the smaller the radius of the peak fillet (i.e., the sharper the peak), the greater the intensity of the secondary vortex generated. The stronger secondary vortex is beneficial to increasing the drag reduction effect of the groove surface.

[0054] In one or more embodiments, a heat preservation layer is provided inside the constant temperature bath. Among them, the material of the heat preservation layer is ceramic fiber zircon shield blanket. Ceramic fiber zircon shield blanket is a commonly used high-temperature heat insulation material in industry. The zirconium-containing ceramic fiber zircon shield blanket can withstand a maximum temperature of 1350 °C, and its thermal conductivity is extremely low, having good heat preservation performance, which can effectively reduce the conduction and loss of temperature.

[0055] Embodiment 2

[0056] In one or more embodiments, as Figure 3 shown, a system for calibrating a magnetic adsorption type surface temperature sensor is provided, including: an industrial personal computer 4, a standard surface temperature sensor 2, a thermometer 5, a thermometer constant temperature box 6, and a constant temperature source for calibrating the magnetic adsorption type surface temperature sensor as described above;

[0057] The thermometer is arranged inside the thermometer constant temperature box, and the thermometer constant temperature box is used to continuously provide a constant temperature environment for the thermometer;

[0058] The measuring ends of the standard surface temperature sensor 2 are all arranged on the upper surface of the hot plate, and the reference end of the standard surface temperature sensor is connected to the measuring channel of the thermometer. Among them, 3 is the magnetic adsorption type surface temperature sensor to be calibrated. 8 is a thermometer, such as a high-precision platinum resistance thermometer, which is used to detect the working chamber temperature of the constant temperature bath.

[0059] As Figure 6 shown, the thermometer constant temperature box can continuously provide a constant temperature environment of 23 °C for the collector, minimizing the influence of the ambient temperature on the reference end of the test device.

[0060] The uniformity and volatility of the temperature field of the constant temperature bath in this embodiment can be stably maintained at ≤0.1 °C for a long time, and can provide a stable and uniform temperature field for the constant temperature surface source hot plate. The constant temperature surface source hot plate adopts a sunken flange, and the working surface is made of high-purity nickel plate, which has ferromagnetic properties. During the calibration process, the magnetic adsorption type surface temperature sensor is automatically adsorbed on the surface of the hot plate, avoiding human intervention and eliminating potential safety hazards. The present invention can realize synchronous calibration of multiple magnetic adsorption type surface temperature sensors, improving the calibration efficiency.

[0061] In the embodiments of the present invention, the industrial control all-in-one computer 4, the thermometer constant temperature box 6, and the constant temperature source 1 for calibrating the magnetic adsorption type surface temperature sensor are all fixed on the lifting table frame 7.

[0062] Among them, the lifting table frame can be set in an electric or manual form according to the actual situation. The lifting table frame integrates all components of the constant temperature surface source, is equipped with universal wheels and can be moved freely, and can be automatically lifted through switch control, which is convenient for on-site use.

[0063] The industrial control computer serves as the main control device of the entire calibration system, contains a dedicated customized software, and realizes communication and control with the monitored system to be calibrated, the thermometer, and the portable constant temperature surface source through RS232 communication.

[0064] The electric lifting table frame integrates all components of the calibration system, is equipped with universal wheels and can be moved freely, and can be automatically lifted through switch control, which is convenient for on-site use.

[0065] In some alternative embodiments, the standard surface temperature sensor can be a self-weight type surface temperature sensor with the model WE-14E-GW1-ANP, and the thermometer can be a thermometer with the model PR293A.

[0066] The test wire is connected to the rear measurement channel of the PR293A thermometer, and the measurement data is collected in real time through the thermometer. Up to 5 standards can be connected. According to the surface temperature source calibration specification, the uniformity and stability of the temperature field of the constant temperature surface source are tested. The technical indicators of the sensor are shown in Table 1.

[0067] Table 1 Technical indicators of the sensor

[0068]

[0069] Figure 7 is the temperature measurement principle diagram of the standard surface temperature sensor. Formula (1) is the thermoelectric potential calculation formula of the high-precision surface thermometer (hereinafter referred to as the thermometer). T is the measurement end of the thermometer, and T0 is the reference end of the thermometer. When testing the temperature field uniformity, T (measurement end) is placed on the surface of the hot plate, and T0 (reference end) is connected to the rear measurement channel of the PR293A thermometer.

[0070] E AB(T,T0) = E AB(T) -E AB(T0) (1)

[0071] In the formula: E AB(T) —The partial thermoelectric potential of the thermocouple nodes A and B at the temperature T, mV;

[0072] E AB(T0) —The partial thermoelectric potential of the thermocouple nodes A and B at the temperature T0, mV.

[0073] As can be seen from the thermoelectric emf calculation formula (1) of the thermometer, the measured value of the surface temperature of the isothermal plane source hot plate is the difference between T and T0. During the measurement process, T (measurement end) is a variable. Only by ensuring that T0 (reference end) is constant can an accurate and reliable measured value of the hot plate surface temperature be obtained.

[0074] The general requirement for the operating ambient temperature of the electrical measurement device (PR293 thermometer) is 23 ± 5°C. Too high or too low ambient temperature will affect the measurement accuracy of the electrical measurement device. The thermometer thermostat can provide a constant temperature environment for the PR293 thermometer, minimizing the interference of the external environment on the high-precision surface thermometer T0 (reference end).

[0075] The operation process of the thermometer thermostat is as Figure 8 shown. The thermostat can correct the temperature control error at the 23°C temperature point by adjusting the offset, and then the thermometer thermostat will use and save the set correction value. For example: when measuring the hot plate surface temperature of the isothermal plane source using a self-weighted surface temperature sensor, if T (measurement end) is 80°C and the temperature of TO (reference end) is not constant, the value of T - TO will change. When the thermometer is placed in the thermostat, the temperature of TO (reference end) will surely be in a stable state (23°C), and T - TO = 80 - 23 = 57°C.

[0076] For example, place the high-precision platinum resistance thermometer into the special jack in the flange to real-time monitor the internal temperature of the working cavity (constant temperature bath) of the portable isothermal plane source; place the standard surface temperature sensor on the surface of the hot plate (sunken flange) of the portable isothermal plane source to real-time monitor the surface temperature of the hot plate of the isothermal plane source. The other wiring terminals of the high-precision platinum resistance thermometer and the standard surface temperature sensor are respectively connected to the rear wiring port of the nano-volt micro-ohm thermometer. Turn on the thermometer thermostat and set it to 23°C, and long press the power-on button for 3 s to turn on the nano-volt micro-ohm thermometer.

[0077] Connect the portable isothermal plane source to the power supply, press the start button to start the portable isothermal plane source, and set the temperature to be detected.

[0078] Use an industrial computer as the main control device of the whole system to automatically control the temperature of the isothermal plane source and read the electrical quantity value of the surface standard device collected by the thermometer, and at the same time realize communication with the monitored system to be calibrated; use a nano-volt micro-ohm thermometer as the measurement device for the high-precision platinum resistance thermometer and the standard surface temperature sensor to respectively real-time monitor the temperature in the constant temperature bath cavity and the surface temperature of the hot plate of the isothermal plane source.

[0079] After the temperature indication of the magnetic adsorption type surface temperature sensor calibration device stabilizes, read the reading value of the standard surface temperature sensor. During the calibration process, according to the temperature test value of the standard surface temperature sensor, the working chamber temperature of the constant temperature bath is corrected in real time, so that the surface temperature of the constant temperature surface source hot plate meets the requirements of the calibration specification.

[0080] According to the calibration specification of the magnetic adsorption type surface thermometer, use the calibration software to preset the threshold value of the difference between the temperature of the high-precision surface temperature measurement sensor and the temperature of the constant temperature bath as the basis for determining and correcting the temperature of the constant temperature bath. During operation, after the temperature of the high-precision surface temperature measurement sensor stabilizes, automatically calculate the difference between its temperature and the temperature control sensor temperature of the constant temperature bath. If the difference does not meet the preset threshold value, the calibration software automatically feeds back the difference to the temperature control program of the constant temperature bath, and the latter automatically adjusts the set temperature of the constant temperature bath according to the feedback value until the temperature of the high-precision surface temperature measurement sensor approaches the initial calibration point temperature. After stabilization, data sampling is carried out. And so on until all temperature points are calibrated. Among them, the calibration software automatically saves the difference of each temperature point according to the above mechanism and automatically applies this difference during the next operation, which can save time, improve work efficiency, and at the same time improve the calibration accuracy of the magnetic adsorption type surface thermometer.

[0081] When the surface temperature of the constant temperature surface source hot plate meets the requirements of the calibration specification, using the built-in software of the magnetic adsorption type surface temperature sensor calibration device, automatic data collection and analysis of the calibration process of the magnetic adsorption type surface temperature sensor can be realized, and a test report can be formed.

[0082] Taking the self-weight type surface thermometer as the standard, measure the surface temperature of the constant temperature surface source hot plate in real time, compare it with the set value of the temperature source, and adjust the set value in real time through the built-in special test software to reduce the deviation between it and the standard value, so as to realize the precise calibration of the magnetic adsorption type surface temperature sensor.

[0083] In this embodiment, during the calibration process, according to the temperature test value of the standard surface temperature sensor, the working chamber temperature of the constant temperature bath is corrected in real time, so that the surface temperature of the constant temperature surface source hot plate meets the requirements of the calibration specification.

[0084] According to the calibration specification of the magnetic adsorption type surface thermometer, use the calibration software to preset the threshold value of the difference between the temperature of the high-precision surface temperature measurement sensor and the temperature of the constant temperature bath as the basis for determining and correcting the temperature of the constant temperature bath. During operation, after the temperature of the high-precision surface temperature measurement sensor stabilizes, automatically calculate the difference between its temperature and the temperature control sensor temperature of the constant temperature bath. If the difference does not meet the preset threshold value, the calibration software automatically feeds back the difference to the temperature control program of the constant temperature bath, and the latter automatically adjusts the set temperature of the constant temperature bath according to the feedback value until the temperature of the high-precision surface temperature measurement sensor approaches the initial calibration point temperature. After stabilization, data sampling is carried out. And so on until all temperature points are calibrated.

[0085] The calibration software automatically saves the difference at each temperature point according to the above mechanism and automatically applies this difference during the next operation, which can save time, improve work efficiency, and at the same time improve the calibration accuracy of the magnetic adsorption type surface thermometer.

[0086] Embodiment 3

[0087] Adopt the system for calibrating the magnetic adsorption type surface temperature sensor as described above; the method for calibrating the magnetic adsorption type surface temperature sensor includes:

[0088] Before the constant temperature bath heats up, adsorb the magnetic adsorption type surface temperature sensor to be calibrated on the surface of the hot plate;

[0089] According to the preset temperature of the reference end of the standard surface temperature sensor, set the constant temperature environment temperature of the temperature measuring instrument constant temperature box;

[0090] Use the measuring end of the standard surface temperature sensor to collect the temperature on the surface of the hot plate and transmit it to the measuring channel of the temperature measuring instrument to obtain the test value of the hot plate surface temperature;

[0091] According to the test value of the hot plate surface temperature, real-time correct the working chamber temperature of the constant temperature bath so that the surface temperature of the hot plate meets the requirements of the calibration specification;

[0092] When the surface temperature of the hot plate meets the requirements of the calibration specification, obtain the temperature value detected by the corresponding magnetic adsorption type surface temperature sensor to be calibrated.

[0093] Among them, during the process of real-time correcting the working chamber temperature of the constant temperature bath, preset the threshold value of the difference between the standard surface temperature sensor and the constant temperature bath temperature as the benchmark for judging and correcting the constant temperature bath temperature;

[0094] After the standard surface temperature sensor is stable, automatically calculate the difference between its temperature and the temperature of the constant temperature bath control sensor. If the difference does not meet the preset threshold value, automatically adjust the set temperature of the constant temperature bath until the difference reaches the preset threshold value.

[0095] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A constant temperature source for calibrating a magnetic surface temperature sensor, characterized in that: include: Constant temperature baths and hot plates; A working medium within a set temperature range is arranged in the thermostatic bath, and the working medium contacts the bottom surface of the hot plate; The hot plate has ferromagnetic properties, so that the magnetic surface temperature sensor is automatically adsorbed on the upper surface of the hot plate; The heat plate is a sunken structure, and the heat plate is sealed on the upper surface of the thermostatic bath; a plurality of grooves are arranged on the lower surface of the heat plate, and the direction of the grooves is consistent with the flow direction of the working medium to ensure that when thermal equilibrium is reached, the temperature of the lower surface of the heat plate is consistent with that of the working medium in the thermostatic bath.

2. The constant temperature source for calibrating a magnetic surface temperature sensor according to claim 1, characterized in that: The groove is a V-shaped groove.

3. The constant temperature source for calibrating a magnetic surface temperature sensor according to claim 2, characterized in that: The depth and width of the V-shaped groove are equal.

4. The constant temperature source for calibrating a magnetic surface temperature sensor according to claim 2, characterized in that: The depth and width of the V-shaped groove are both 12.5 mm, and the fillet radius at the peak of the V-shaped groove is less than 25%.

5. The constant temperature source for calibrating a magnetic surface temperature sensor according to claim 1, characterized in that: A heat preservation layer is arranged inside the thermostatic bath.

6. The constant temperature source for calibrating a magnetic surface temperature sensor according to claim 5, characterized in that: The material of the thermal insulation layer is a ceramic fiber zirconium shield blanket.

7. A system for calibrating a magnetic surface temperature sensor, characterized in that: include: An industrial control integrated machine, a standard surface temperature sensor, a thermometer, a thermometer constant temperature box, and a constant temperature source for calibrating a magnetic surface temperature sensor as claimed in any one of claims 1 to 6; The thermometer is arranged in the thermostat box, and the thermostat box is used to continuously provide a constant temperature environment for the thermometer; The measuring ends of the standard surface temperature sensors are all arranged on the upper surface of the hot plate, and the reference ends of the standard surface temperature sensors are connected to the measuring channels of the temperature measuring instrument.

8. The system for calibrating a magnetic surface temperature sensor according to claim 1, characterized in that: The industrial control integrated machine, the thermometer constant temperature box and the constant temperature source for calibrating the magnetic surface temperature sensor are all fixed on the lifting platform.

9. A method for calibrating a magnetic surface temperature sensor, characterized in that: A system for calibrating a magnetic surface temperature sensor as claimed in any one of claims 7 to 8 is used; the method for calibrating a magnetic surface temperature sensor comprises: Before the constant temperature bath is heated up, the calibrated magnetic surface temperature sensor is attached to the surface of the hot plate; According to the preset temperature of the reference end of the standard surface temperature sensor, set the constant temperature environment temperature of the thermostat of the thermometer; The temperature of the hot plate surface is collected by the measuring end of the standard surface temperature sensor and transmitted to the measuring channel of the temperature measuring instrument to obtain the test value of the hot plate surface temperature; According to the test value of the hot plate surface temperature, the working chamber temperature of the thermostatic bath is corrected in real time so that the surface temperature of the hot plate meets the calibration specification requirements; When the surface temperature of the hot plate reaches the calibration specification requirement, the corresponding temperature value detected by the calibrated magnetic surface temperature sensor is obtained.

10. The method for calibrating a magnetic surface temperature sensor according to claim 9, characterized in that: In the process of real-time correction of the working chamber temperature of the thermostatic bath, a threshold value of the difference between the standard surface temperature sensor and the thermostatic bath temperature is preset as a reference for determining the correction of the thermostatic bath temperature; When the standard surface temperature sensor is stable, the difference between it and the temperature of the constant temperature bath temperature control sensor is automatically calculated. If the difference does not meet the preset threshold, the set temperature of the constant temperature bath is automatically adjusted until the difference reaches the preset threshold.

Images