NTC (Negative Temperature Coefficient)-based wide-temperature-range standard-grade thermometer and temperature measurement method

Abstract

The invention relates to the technical field of temperature measurement, and discloses an NTC (Negative Temperature Coefficient)-based wide-temperature-range standard-grade thermometer and a temperature measurement method, which remarkably widens the temperature measurement range by integrating at least two NTC sensors with different temperature measurement ranges. Meanwhile, in a temperature measurement interval in which each NTC sensor is responsible, high-precision temperature measurement can be ensured to be provided, so that the temperature sensor not only has a series of remarkable advantages of wide temperature range, high precision, high stability, high shock resistance and the like, but also shows lower cost and expenditure compared with a traditional platinum resistance thermometer in the aspect of comprehensive use cost, and is suitable for popularization and application. And the structural design of the thermometer is greatly simplified, so that the requirements of industrial and scientific research fields on wide-temperature-range high-precision measurement can be better met, and further development of a temperature measurement technology can be promoted.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature measurement, and in particular to an NTC-based wide-temperature range standard-grade thermometer and a temperature measurement method. Background Art

[0002] With the continuous advancement and innovation of technology in the industrial field and scientific research, researchers have increasingly higher requirements for the accuracy of temperature measurement, and the pursuit of more accurate data results has become an industry consensus.

[0003] In the current measurement transfer system, platinum resistance thermometers have firmly occupied the most important position as measurement standards due to their excellent performance, and are the preferred temperature sensor type in the field of high-precision measurement. This position is due to its long-term reliability and accuracy verification. However, with the continuous development and maturity of negative temperature coefficient thermistor (NTC) technology, its application in high-precision measurement scenarios is becoming increasingly widespread, gradually showing its unique advantages and potential.

[0004] Although the existing thermometer technology has made remarkable achievements, there are still some problems that need to be solved. Specifically:

[0005] (I) When using platinum resistance thermometers as temperature sensors, there are two main challenges. On the one hand, high-precision platinum resistance thermometers usually adopt a structural design in which a bent platinum wire is wrapped around a quartz skeleton. Although this structure achieves sensitive temperature measurement to a certain extent, when the temperature changes, the platinum wire will be affected by stress, which will cause the resistance value to drift, affecting the stability and accuracy of the measurement. In addition, the seismic resistance of this structure is relatively poor, which limits its application scenarios and can usually only be used in relatively stable environments such as laboratories. On the other hand, the resistance-temperature change rate of the platinum resistance thermometer is relatively small. In order to achieve high-precision temperature measurement, it is often necessary to equip it with high-precision secondary instruments such as temperature measuring bridges for use, which undoubtedly increases the cost and technical threshold of use.

[0006] (II) When NTC is used as a high-precision temperature sensor, although it has unique advantages in some aspects, it also has obvious limitations. Since the resistance value of NTC changes exponentially with the increase of temperature, and the range of change is large, its application in precision measurement is limited to a certain extent. At present, NTC is mostly used for measurement in a narrow temperature range, and its measurement range generally does not exceed 100°C. NTC technology is still difficult to meet the needs of high-precision measurement in a wide temperature range, which to a certain extent limits its application and promotion in a wider range of fields.

[0007] Therefore, in view of the problems and deficiencies existing in the existing thermometer technology, it is necessary to conduct in-depth research and exploration, seek more effective technical improvement solutions, so as to improve the accuracy and stability of temperature measurement and meet the ever-developing industrial and scientific research needs.

[0008] The above information is given as background information only to assist in understanding the present disclosure, and does not determine or admit whether any of the above content can be used as the prior art relative to the present disclosure. Summary of the Invention

[0009] The present invention provides a wide-temperature-range standard-level thermometer based on NTC and a temperature measurement method to solve the problems existing in the prior art.

[0010] To achieve the above object, the present invention provides the following technical solutions:

[0011] In a first aspect, the present aspect provides a wide-temperature-range standard-level thermometer based on NTC, including N NTC sensors, a metal housing, leads, and an instrument; wherein,

[0012] The N NTC sensors are encapsulated in the same metal housing;

[0013] Each of the NTC sensors is respectively connected to the instrument through a corresponding one of the leads;

[0014] The base resistance values of each of the NTC sensors are different, so that the temperature measurement ranges of each of the NTC sensors are different, and N is a natural number greater than or equal to 2;

[0015] The NTC sensors are used to measure the temperature information of the object to be measured when the metal housing comes into contact with the object to be measured;

[0016] The leads are used to transmit the measured temperature information of the object to be measured to the instrument;

[0017] The instrument is used to switch and connect to different leads to receive the temperature information measured by different NTC sensors and display it.

[0018] Further, in the wide-temperature-range standard-level thermometer based on NTC, the temperature measurement ranges of the N NTC sensors are continuously overall.

[0019] Further, in the wide-temperature-range standard-level thermometer based on NTC, the metal housing is made of a high thermal conductivity material.

[0020] Further, in the wide-temperature-range standard-level thermometer based on NTC, each of the leads is respectively wrapped in a corresponding first outer sheath;

[0021] All the leads are wrapped in the same second outer sheath.

[0022] Further, in the wide-temperature-range standard-level thermometer based on NTC, the lead wires are made of heat-resistant and corrosion-resistant conductive materials;

[0023] The first outer coating and the second outer coating are made of heat-resistant, flexible, and wear-resistant insulating materials.

[0024] Further, in the wide-temperature-range standard-level thermometer based on NTC, the lead wires are detachably connected to the instrument through a connector.

[0025] In a second aspect, the present invention provides a temperature measurement method, which uses the wide-temperature-range standard-level thermometer based on NTC provided in the first aspect above. The method includes:

[0026] S1. In the normal mode, when the metal housing contacts the object to be measured, the NTC sensor with the smallest temperature measurement range measures the temperature information of the object to be measured, and transmits the measured temperature information of the object to be measured to the instrument through the lead wires;

[0027] S2. The instrument determines whether the temperature information exceeds the temperature measurement range of the corresponding NTC sensor; if not, S3 is executed; if so, S4 is executed;

[0028] S3. The instrument displays the temperature information;

[0029] S4. The instrument switches to connect to the lead wires corresponding to the NTC sensor with the second smallest temperature measurement range to receive the temperature information measured by the NTC sensor with the second smallest temperature measurement range, and returns to execute S2.

[0030] Further, in the temperature measurement method, after S3, the method further includes:

[0031] S5. During the continuous temperature measurement process, the instrument determines whether the absolute value of the difference between the temperature information measured this time and the temperature information measured last time exceeds a preset range, and the temperature information measured this time is lower than the temperature measurement range of the NTC sensor used for this temperature measurement; if so, S6 is executed; if not, S7 is executed;

[0032] S6. The instrument switches to connect to the lead wires corresponding to the first target NTC sensor to receive the temperature information measured by it; the temperature measurement range of the first target NTC sensor is smaller than the temperature measurement range of the NTC sensor used for this temperature measurement, and it is displayed;

[0033] S7. The instrument determines whether the absolute value of the difference between the temperature information measured this time and the temperature information measured last time exceeds a preset range, and the temperature information measured this time is higher than the temperature measurement range of the NTC sensor used for this temperature measurement; if so, execute S8, if not, execute S9;

[0034] S8. The instrument switches to connect to the lead corresponding to the second target NTC sensor to receive the temperature information measured by it; the temperature measurement range of the second target NTC sensor is larger than the temperature measurement range of the NTC sensor used for this temperature measurement, and display it;

[0035] S9. The instrument displays the temperature information.

[0036] Further, in the temperature measurement method, the method further includes:

[0037] S100. In the self-check mode, when the metal shell touches the object for calibration, the instrument sequentially connects to the leads corresponding to two NTC sensors with continuous temperature measurement ranges to sequentially receive the temperature information measured by the two NTC sensors with continuous temperature measurement ranges; the temperature of the object for calibration is in the cross-section of the temperature measurement ranges of the two NTC sensors with continuous temperature measurement ranges;

[0038] S200. The instrument determines whether the absolute value of the difference between the two received temperature information is greater than a preset threshold; if not, execute S300, if so, execute S400;

[0039] S300. The instrument determines that neither of the two NTC sensors used for this temperature measurement is abnormal;

[0040] S400. The instrument determines that at least one of the two NTC sensors used for this temperature measurement is abnormal.

[0041] Further, in the temperature measurement method, after S400, the method further includes:

[0042] S500. The instrument triggers an alarm mechanism.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] A wide-temperature-range standard-level thermometer based on NTC and a temperature measurement method provided by the present invention integrate at least two NTC sensors with different temperature measurement ranges, achieving a significant broadening of the temperature measurement range. At the same time, within the temperature measurement intervals respectively responsible for each NTC sensor, highly accurate temperature measurement can be ensured. It not only has a series of remarkable advantages such as a wide temperature range, high precision, high stability, and high shock resistance, but also shows lower cost expenditure compared with traditional platinum resistance thermometers in terms of the comprehensive usage cost, and greatly simplifies the structural design of the thermometer, thus better meeting the requirements of the industrial and scientific research fields for wide-temperature-range high-precision measurement and facilitating the further development of temperature measurement technology.

[0045] The present invention has other characteristics and advantages, which will be obvious from the accompanying drawings incorporated herein and the subsequent detailed description, or will be described in detail in the accompanying drawings incorporated herein and the subsequent detailed description. These accompanying drawings and detailed description are used together to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0047] Figure 1 is a (three-dimensional) structural schematic diagram of a wide-temperature-range standard-level thermometer based on NTC provided by Embodiment 1 of the present invention;

[0048] Figure 2 is a schematic structural diagram of a wide-temperature-range standard-level thermometer based on NTC provided by Embodiment 1 of the present invention;

[0049] Figure 3 is one of the flow schematic diagrams of a temperature measurement method provided by Embodiment 2 of the present invention;

[0050] Figure 4 is one of the flow schematic diagrams of a temperature measurement method provided by Embodiment 2 of the present invention;

[0051] Figure 5 is one of the flow schematic diagrams of a temperature measurement method provided by Embodiment 2 of the present invention;

[0052] Figure 6 is one of the flow schematic diagrams of a temperature measurement method provided by Embodiment 2 of the present invention.

[0053] Reference numerals:

[0054] NTC sensor 1, metal housing 2, lead 3, instrument 4, second outer sheath 5. Detailed implementation manners

[0055] To describe in detail the possible application scenarios, technical principles, specific implementable solutions, achievable purposes and effects of this application, etc., the following will be described in detail in conjunction with the listed specific embodiments and with reference to the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of this application, so they are only used as examples and cannot be used to limit the protection scope of this application.

[0056] Referring to "embodiments" herein means that the specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of this application. The term "embodiment" that appears in various positions in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or relevance to other embodiments. In principle, in this application, as long as there is no technical contradiction or conflict, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0057] Unless otherwise defined, the meanings of the technical terms used herein are the same as those generally understood by those skilled in the technical field to which this application belongs; the use of the relevant terms herein is only for describing specific embodiments and is not intended to limit this application.

[0058] In the description of this application, the phrase "and / or" is an expression used to describe the logical relationship between objects, indicating that there can be three relationships, for example, A and / or B, which means: there is A, there is B, and there is both A and B at the same time. In addition, the character " / " in this article generally represents an "or" logical relationship between the associated objects before and after.

[0059] In this application, terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual quantity, primary or secondary, or order relationship between these entities or operations.

[0060] Without more limitations, in this application, the expressions such as "including", "comprising", "having" or other similar expressions used in the statements are intended to cover non-exclusive inclusion. These expressions do not exclude that there may be other elements in the process, method or product including the said elements, so that the process, method or product including a series of elements may not only include those defined elements, but also include other elements not explicitly listed, or also include elements inherent to this process, method or product.

[0061] In this application, expressions such as "greater than", "less than", "exceeding", etc. are understood not to include the number itself; expressions such as "above", "below", "within", etc. are understood to include the number itself. In addition, in the description of the embodiments of this application, the meaning of "a plurality of" is two or more (including two). Similar expressions related to "many", such as "multiple groups", "multiple times", etc., are understood in this way unless otherwise specifically and clearly defined.

[0062] In the description of the embodiments of this application, the spatially related expressions used, such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "perpendicular", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the specific embodiment or the drawing. It is only for the convenience of describing the specific embodiments of this application or for the reader to understand, rather than indicating or implying that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, it should not be construed as a limitation to the embodiments of this application.

[0063] Unless otherwise clearly specified or limited, in the description of the embodiments of this application, the terms such as "installed", "connected", "coupled", "fixed", "set", etc. should be understood in a broad sense. For example, the "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be directly connected, or indirectly connected through an intermediate medium; it can be the communication inside two components or the interaction relationship between two components. For those skilled in the art to which this application belongs, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

[0064] Embodiment 1

[0065] In view of the defects existing in the above-mentioned prior art, based on the rich practical experience and professional knowledge in the design and manufacture of this field for many years, and in cooperation with the application of theory, the applicant actively conducts research and innovation in the hope of creating a technology that can solve the defects in the prior art. After continuous research, design, and repeated trial production of samples and improvement, the present invention with practical value is finally created.

[0066] Please refer to Figure 1-2 , the embodiment of the present invention provides a wide-temperature-range standard-level thermometer based on NTC, which mainly consists of N NTC sensors 1, a metal shell 2, leads 3, and an instrument 4. The specific configurations and functions of each part are as follows:

[0067] First, the N NTC sensors 1 are ingeniously encapsulated inside the same metal housing 2. Such a design not only helps protect the sensors from external environmental interference but also achieves structural compactness and integration.

[0068] Secondly, each NTC sensor 1 is connected to the instrument 4 through a dedicated lead 3, ensuring the independence and accuracy of signal transmission. This one-to-one connection method effectively avoids signal interference between each other and guarantees the reliable transmission of temperature information.

[0069] Furthermore, one of the innovative features of the present invention is that the base resistance of each NTC sensor 1 is carefully set so that they each have different temperature measurement ranges. Here, N is a natural number and N≥2, meaning that at least two NTC sensors 1 with different temperature measurement ranges are integrated in the thermometer system. Such a design concept greatly broadens the measurement range of the thermometer, enabling it to adapt to more diverse temperature measurement requirements.

[0070] In specific applications, when the metal housing 2 comes into contact with the object to be measured, the built-in NTC sensors 1 will quickly respond and accurately measure the temperature information of the object to be measured. Subsequently, this information is transmitted in real time to the instrument 4 through the corresponding leads 3.

[0071] As the core processing and display unit of the entire thermometer system, the instrument 4 has an intelligent switching function and can be connected to different leads 3 as needed to receive and display the temperature information from different NTC sensors 1. This feature not only improves the flexibility of use of the thermometer but also provides strong support for it in complex and changing temperature measurement environments.

[0072] In summary, through the integration of at least two NTC sensors 1 with non-overlapping temperature measurement ranges, the embodiment of the present invention successfully achieves a significant expansion of the temperature measurement range. At the same time, thanks to the high-precision measurement ability of each NTC sensor 1 within its specific temperature measurement range, this thermometer system not only has multiple advantages such as a wide temperature range, high precision, high stability, and high shock resistance but also shows obvious economy in terms of the comprehensive use cost compared with traditional platinum resistance thermometers. In addition, its simplified structural design greatly reduces the manufacturing difficulty and maintenance cost of the thermometer, thus better meeting the urgent needs of the industrial and scientific research fields for wide-temperature-range and high-precision temperature measurement. This innovative achievement undoubtedly injects new vitality and impetus into the further development of temperature measurement technology.

[0073] In a specific implementation manner of this embodiment, the temperature measurement ranges of the N NTC sensors 1 are carefully designed to present a continuous characteristic as a whole. This continuity means that the temperature measurement ranges of multiple NTC sensors 1 are logically connected seamlessly to jointly form a continuous and wide temperature measurement interval, thereby meeting the requirement for temperature measurement in a wider range.

[0074] It should be further clarified that this continuity of the temperature measurement range can be divided into two cases, namely, the overlap of the temperature measurement ranges, and the non - overlap but end - to - end connection of the temperature measurement ranges.

[0075] The first case is the overlap of the temperature measurement ranges. Specifically, there is a certain overlap in the end parts of the temperature measurement ranges of multiple NTC sensors. For example, the temperature measurement range of sensor A is set from - 40°C to 100°C, while the temperature measurement range of sensor B is 80°C to 150°C. In this case, within the temperature range of 80°C to 100°C, the temperature measurement ranges of the two sensors overlap. This design not only improves the redundancy of temperature measurement but also enhances the reliability of the measurement. Because within the overlapping area of the temperature measurement ranges of the two sensors, the accuracy of temperature measurement can be ensured by comparing the measurement results of the two sensors, thereby effectively reducing the measurement deviation caused by the error of the sensor itself or external interference.

[0076] The second case is the non - overlap but end - to - end connection of the temperature measurement ranges. That is, the temperature measurement ranges of multiple NTC sensors are connected tightly in sequence, but there is no overlapping part between them. For example, the temperature measurement range of sensor A is - 40°C to 100°C, the temperature measurement range of sensor B is the subsequent 101°C to 150°C, and the temperature measurement range of sensor C is the following 151°C to 200°C. In this case, each sensor is responsible for a specific, non - overlapping temperature interval, and they cooperate together to cover a wider temperature range from - 40°C to 200°C. However, it should be noted that this completely non - overlapping and end - to - end connection situation is relatively rare in practical applications because, in order to ensure the continuity and accuracy of measurement, a certain degree of overlap is usually left between the temperature measurement ranges of adjacent sensors.

[0077] In summary, in this embodiment, by carefully designing the temperature measurement ranges of the N NTC sensors 1, the continuity of the temperature measurement range is achieved. Whether through the overlap of the temperature measurement ranges or the non - overlap but end - to - end connection method, the measurement range of the thermometer is effectively broadened, the measurement accuracy and reliability are improved, and the requirements for high - precision measurement in a wide temperature range in the industrial and scientific research fields are met.

[0078] In a specific implementation manner of this embodiment, the metal shell 2 is made of a material with high thermal conductivity. This design choice is based on the consideration of the accuracy of temperature measurement and the response speed.

[0079] The high - thermal - conductivity material can quickly and effectively transfer the temperature of the object to be measured to the built - in NTC sensor 1. When the metal housing 2 contacts the object to be measured, if the housing material has good thermal conductivity, the temperature of the object to be measured can be evenly distributed on the surface and inside of the housing in a short time, and then accurately sensed by the NTC sensor 1.

[0080] In addition, the high - thermal - conductivity material helps to improve the response speed of the thermometer. In a measurement environment with rapid temperature changes, if the thermal conductivity of the metal housing 2 is poor, the response of the thermometer may lag, resulting in a deviation between the measurement result and the actual temperature. Using a high - thermal - conductivity material can effectively reduce this lag phenomenon, enabling the thermometer to more timely reflect the temperature change of the object to be measured.

[0081] Therefore, in this embodiment, a high - thermal - conductivity material is selected as the manufacturing material for the metal housing 2, aiming to improve the measurement accuracy and response speed of the thermometer.

[0082] In a specific implementation manner of this embodiment, the structural design of the lead 3 is carefully considered and optimized to ensure the reliability and durability of the thermometer.

[0083] Specifically, each lead 3 is respectively wrapped in a corresponding first outer covering layer. This design can effectively protect the lead 3 from external environmental interference and damage, such as mechanical wear, chemical corrosion, or electrical interference. The first outer covering layer, as the direct protective layer of the lead 3, has its material and thickness carefully selected to ensure good insulation performance and mechanical strength.

[0084] In addition, after all the leads 3 are wrapped by their respective first outer covering layers, they are also jointly wrapped in the same second outer covering layer 5. The second outer covering layer 5, as an overall protective layer, tightly bundles all the leads 3 together, forming a neat and strong cable bundle. This design can not only further enhance the anti - interference ability of the leads 3 but also improve the overall aesthetics and manageability of the thermometer.

[0085] In practical applications, this multi - layer - wrapped lead design can significantly improve the reliability and stability of the thermometer. Especially in industrial environments, the thermometer may be tested under various harsh conditions, such as high temperature, humidity, vibration, and electromagnetic interference. By adopting this multi - layer - wrapped lead design, the influence of these external factors on the performance of the thermometer can be effectively reduced, ensuring the accuracy and reliability of temperature measurement.

[0086] Therefore, this embodiment selects this multi - layer - wrapped lead design to improve the durability and reliability of the thermometer, enabling it to better adapt to various complex and changeable measurement environments.

[0087] In a specific implementation manner of this embodiment, strict considerations and optimizations have been carried out on the material selection of the lead wire 3 and its outer sheath to ensure the stability and reliability of the thermometer in harsh environments such as high temperature and corrosion.

[0088] First of all, the lead wire 3 is made of a conductive material that is resistant to high temperature and corrosion. This material can maintain stable electrical conductivity in a high-temperature environment and will not undergo significant resistance changes due to temperature increase, thus ensuring the accuracy of temperature measurement. At the same time, this material also has good corrosion resistance and can resist the erosion of various chemical substances, extending the service life of the lead wire 3.

[0089] Secondly, both the first outer sheath and the second outer sheath 5 are made of an insulating material that is resistant to high temperature, flexible, and wear-resistant. This insulating material can maintain stable physical and chemical properties in a high-temperature environment and will not soften, deform, or decompose due to temperature increase, thus effectively protecting the lead wire 3 from external environmental interference and damage. At the same time, this material also has good flexibility and wear resistance, can adapt to the bending and friction of the thermometer during use, and reduce damage caused by mechanical stress.

[0090] By using this conductive material that is resistant to high temperature and corrosion and this insulating material that is resistant to high temperature, flexible, and wear-resistant, the thermometer of this embodiment can maintain stable performance and long life in various harsh environments. Especially in industrial environments such as high temperature and corrosion, this material selection can significantly improve the reliability and durability of the thermometer and ensure the accuracy and stability of temperature measurement.

[0091] In a specific implementation manner of this embodiment, the connection method between the lead wire 3 and the instrument 4 adopts a detachable design, that is, the two are connected through a connector. This design method brings many advantages and conveniences.

[0092] First of all, the detachable connection method makes the connection between the lead wire 3 and the instrument 4 more flexible. In practical applications, it may be necessary to adjust the connection method of the lead wire 3 according to different measurement requirements or replace different NTC sensors 1. By adopting the connector design, the lead wire 3 can be easily disassembled and reconnected without complex modifications or replacements to the entire thermometer system, greatly improving the flexibility and convenience of use.

[0093] Secondly, the detachable connection method also facilitates the maintenance and repair of the thermometer. If the lead wire 3 or the instrument 4 fails or needs to be calibrated, the connection can be quickly disconnected through the connector, the faulty component can be replaced or repaired, and then reconnected, greatly shortening the maintenance time and reducing the maintenance cost.

[0094] In addition, using a connector for connection can also improve the scalability of the thermometer system. In the future, if more NTC sensors 1 or leads 3 need to be added, new components can be connected to the system simply by means of additional connectors, without the need for large-scale modification of the existing system, making it easier for the thermometer system to adapt to future expansion and upgrade requirements.

[0095] To sum up, in this embodiment, a detachable connection between the lead 3 and the instrument 4 is achieved by using a connector, which not only improves the flexibility and convenience of the thermometer, but also facilitates maintenance and repair, and enhances the scalability of the system, providing more possibilities and conveniences for the wide application of the thermometer.

[0096] Although terms such as NTC sensors and instruments are used more frequently in this application, the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional limitation is contrary to the spirit of the present invention.

[0097] A wide-temperature-range standard-level thermometer based on NTC provided by an embodiment of the present invention significantly broadens the temperature measurement range by integrating at least two NTC sensors with different temperature measurement ranges. At the same time, within the temperature measurement intervals respectively responsible for each NTC sensor, highly accurate temperature measurement can be ensured, making it not only have a series of remarkable advantages such as wide temperature range, high precision, high stability, and high shock resistance, but also show lower cost expenditure in terms of the comprehensive use cost compared with traditional platinum resistance thermometers, and greatly simplifies the structural design of the thermometer, thus being able to better meet the needs of industrial and scientific research fields for wide-temperature-range high-precision measurement and being conducive to promoting the further development of temperature measurement technology.

[0098] Embodiment 2

[0099] Please refer to Figure 3 , Figure 3 which is a schematic flowchart of a temperature measurement method provided by Embodiment 2 of the present invention. This method is implemented by using the wide-temperature-range standard-level thermometer based on NTC provided in the above Embodiment 1 and is applicable to the scenario of measuring the temperature of an object to be measured. The method specifically includes the following steps:

[0100] S1. In the normal mode, when the metal housing comes into contact with the object to be measured, the NTC sensor with the smallest temperature measurement range measures the temperature information of the object to be measured and transmits the measured temperature information of the object to be measured to the instrument through the lead.

[0101] It should be noted that the instrument has at least two modes. When the temperature of the object to be measured needs to be measured normally, the instrument is in the normal mode.

[0102] Among multiple NTC sensors, select the sensor with the smallest temperature measurement range as the initial measurement device. This is because usually the measurement starts from the smallest measurement range to gradually obtain the most accurate temperature data.

[0103] The temperature information measured by the NTC sensor is transmitted to the instrument through the lead wire for further processing and display.

[0104] S2. The instrument determines whether the temperature information exceeds the temperature measurement range of the corresponding NTC sensor; if not, execute S3, if so, execute S4.

[0105] It should be noted that after receiving the temperature information, the instrument will determine whether this information is within the temperature measurement range of the currently used NTC sensor.

[0106] If the temperature information is within the temperature measurement range (not exceeding), then execute S3.

[0107] If the temperature information exceeds the temperature measurement range, then execute S4.

[0108] S3. The instrument displays the temperature information.

[0109] It should be noted that when the temperature information is within the temperature measurement range, the instrument will display this information to the user. This is usually achieved through a digital display screen or an analog pointer.

[0110] S4. The instrument switches and connects to the lead wire corresponding to the NTC sensor with the second smallest temperature measurement range to receive the temperature information measured by the NTC sensor with the second smallest temperature measurement range, and returns to execute S2.

[0111] It should be noted that if the temperature measurement range of the current NTC sensor is not sufficient to cover the actual temperature of the object to be measured, the instrument will automatically switch to the NTC sensor with the second smallest temperature measurement range. This is achieved by changing the connection between the instrument and the lead wire corresponding to the sensor, usually by switching the internal circuit or relay.

[0112] After switching to the new NTC sensor, the instrument will execute the measurement process again, starting from S2, that is, determining whether the new temperature information is within the temperature measurement range of the new sensor.

[0113] This process will repeat continuously until an NTC sensor that can accurately measure the temperature of the object to be measured is found. Although each NTC sensor has its nominal temperature measurement range, it can actually still work slightly beyond this range, but the accuracy will decrease. Therefore, when the measured temperature exceeds the nominal range of the current sensor, it indicates that the temperature of the object to be measured exceeds the temperature measurement range of the NTC sensor used for this measurement, and the NTC sensor used for this measurement is not suitable. At this time, the instrument knows that it needs to switch to the next sensor with a larger temperature measurement range.

[0114] In summary, this method ensures accurate temperature measurement values under different temperature conditions by automatically switching NTC sensors with different temperature measurement ranges.

[0115] Please refer to Figure 4 , on the basis of Figure 3 , after S3, the method may further include the following steps:

[0116] S5. During the continuous temperature measurement process, the instrument determines whether the absolute value of the difference between the temperature information measured this time and the temperature information measured last time exceeds a preset range, and the temperature information measured this time is lower than the temperature measurement range of the NTC sensor used for this temperature measurement; if so, execute S6, if not, execute S7.

[0117] It should be noted that during the continuous temperature measurement process, the instrument not only focuses on the current temperature value but also compares the temperature change between this measurement and the previous measurement.

[0118] The instrument calculates the absolute value of the difference between the temperature information measured this time and the temperature information measured last time and determines whether this difference exceeds the preset range. At the same time, the instrument also checks whether the temperature information measured this time is lower than the lower limit of the temperature measurement range of the currently used NTC sensor. If the difference exceeds the preset range and the temperature is lower than the temperature measurement range, execute S6. Otherwise, execute S7. The purpose of this design is to avoid frequent switching of different NTC sensors for temperature measurement.

[0119] S6. The instrument switches to connect to the lead corresponding to the first target NTC sensor to receive the temperature information measured by it; the temperature measurement range of the first target NTC sensor is smaller than the temperature measurement range of the NTC sensor used for this temperature measurement, and it is displayed.

[0120] It should be noted that when the temperature of the object to be measured suddenly drops and the change range exceeds the expectation, the instrument may consider that the current sensor is no longer suitable for measurement, so it switches to the first target NTC sensor with a smaller temperature measurement range.

[0121] After switching, the meter receives and displays the temperature information measured by the first target sensor.

[0122] S7. The meter determines whether the absolute value of the difference between the temperature information measured this time and the temperature information measured last time exceeds a preset range, and the temperature information measured this time is higher than the temperature measurement range of the NTC sensor used for this temperature measurement; if so, execute S8, if not, execute S9.

[0123] It should be noted that this step is similar to S5, but this time it focuses on whether the temperature suddenly rises and exceeds the upper limit of the temperature measurement range of the current sensor. If the difference exceeds the preset range and the temperature is higher than the temperature measurement range, execute S8. Otherwise, execute S9.

[0124] S8. The meter switches to connect to the lead corresponding to the second target NTC sensor to receive the temperature information measured by it; the temperature measurement range of the second target NTC sensor is larger than the temperature measurement range of the NTC sensor used for this temperature measurement, and displays it.

[0125] It should be noted that when the temperature suddenly rises and the change range exceeds the expectation, the meter switches to the second target NTC sensor with a larger temperature measurement range.

[0126] After switching, the meter receives and displays the temperature information measured by the second target sensor.

[0127] S9. The meter displays the temperature information.

[0128] It should be noted that if the temperature change does not exceed the preset range, or although it exceeds but is still within the temperature measurement range of the current sensor, the meter normally displays the currently measured temperature information.

[0129] Through these steps, the meter can avoid frequent switching of different NTC sensors, and more intelligently respond to sudden changes during the temperature measurement process, automatically select the appropriate NTC sensor to ensure the accuracy and reliability of the measurement.

[0130] Please refer to Figure 5 , a temperature measurement method provided by an embodiment of the present invention also has a self-checking function. Specifically, the method further includes:

[0131] S100. In the self-checking mode, when the metal shell touches the object for calibration, the meter sequentially connects to the leads corresponding to two NTC sensors with continuous temperature measurement ranges to sequentially receive the temperature information measured by the two NTC sensors with continuous temperature measurement ranges; the temperature of the object for calibration is in the intersection segment of the temperature measurement ranges of the two NTC sensors with continuous temperature measurement ranges.

[0132] It should be noted that the instrument has multiple working modes, one of which is the self-check mode. In this mode, the instrument can verify the performance of its internal NTC sensor.

[0133] To perform the check, a calibration object with a known temperature is required. The temperature of this object is selected within the intersection section of the NTC sensors in two consecutive temperature measurement ranges, that is, this temperature value can be measured by both sensors.

[0134] The instrument will sequentially connect two NTC sensors with consecutive temperature measurement ranges and receive the temperature information measured by them. This is done to compare the measurement accuracy of the two sensors under the same conditions.

[0135] S200. The instrument determines whether the absolute value of the difference between the two received temperature information is greater than a preset threshold; if not, it executes S300, and if so, it executes S400.

[0136] It should be noted that the instrument calculates the absolute value of the difference between the temperature information measured by the two NTC sensors and compares this difference with the preset threshold.

[0137] If the difference is less than or equal to the preset threshold, it indicates that the measurement results of the two sensors are similar and may both be accurate, and S300 is executed. If the difference is greater than the preset threshold, it indicates that there are significant differences in the measurement results of the two sensors, and at least one sensor may be abnormal, and S400 is executed.

[0138] S300. The instrument determines that neither of the two NTC sensors used for this temperature measurement is abnormal.

[0139] It should be noted that when the measurement results of the two sensors are similar, the instrument determines that both sensors are normal and there is no abnormality.

[0140] S400. The instrument determines that at least one of the two NTC sensors used for this temperature measurement is abnormal.

[0141] It should be noted that when there are significant differences in the measurement results of the two sensors, the instrument determines that at least one sensor is abnormal. This may be due to sensor aging, damage, or other reasons resulting in inaccurate measurement.

[0142] Through this self-check function, the instrument can periodically or as needed verify the performance of its internal NTC sensors to ensure the accuracy and reliability of the measurement. This is very important for a temperature measurement system that needs to operate stably for a long time, because it can help detect and handle sensor abnormalities in a timely manner and avoid measurement errors caused by sensor problems.

[0143] Please refer to Figure 6, after S400, the method further includes:

[0144] S500, the instrument triggers an alarm mechanism.

[0145] It should be noted that in step S400, the instrument has determined that at least one of the two NTC sensors used for this temperature measurement is abnormal. In order to notify the user or operator in a timely manner, the instrument will trigger an alarm mechanism.

[0146] The alarm mechanism can be implemented in various ways, such as emitting an audible alarm, displaying an alarm message on the screen of the instrument, sending an alarm signal to a remote monitoring system, etc. The specific method depends on the design of the instrument and the needs of the user.

[0147] The purpose of triggering the alarm mechanism is to attract the attention of the user and let them know that there may be a problem with the temperature measurement function of the instrument, and it needs to be checked and repaired in a timely manner. This can avoid measurement errors caused by sensor abnormalities and ensure the accuracy and reliability of temperature measurement.

[0148] In summary, step S500 is an important response measure after the instrument discovers sensor abnormalities during the self-check process. By triggering the alarm mechanism, it notifies the user in a timely manner to ensure the normal operation of the temperature measurement system.

[0149] Finally, it should be noted that although the above embodiments have been described in the text and drawings of the specification of this application, the patent protection scope of this application cannot be limited thereby. Any technical solutions obtained by equivalent structure or equivalent process substitution or modification based on the essential concept of this application and using the content recorded in the text and drawings of the specification of this application, as well as those directly or indirectly implementing the technical solutions of the above embodiments in other related technical fields, are all included in the patent protection scope of this application.

Claims

1. A wide temperature range standard grade thermometer based on NTC, characterized in that: It comprises N NTC sensors (1), a metal housing (2), leads (3) and a meter (4); wherein: N NTC sensors (1) are packaged in the same metal housing (2); Each of the NTC sensors (1) is connected to the instrument (4) via a corresponding lead wire (3); The basic resistance value of each NTC sensor (1) is different, so that the temperature measurement range of each NTC sensor (1) is different, and N is a natural number greater than or equal to 2; The NTC sensor (1) is used to measure temperature information of the object to be measured when the metal housing (2) contacts the object to be measured; The lead wire (3) is used to transmit the measured temperature information of the measured object to the instrument (4); The instrument (4) is used to switch to connect to different leads (3) to receive and display temperature information measured by different NTC sensors (1).

2. The NTC-based wide temperature range standard-grade thermometer according to claim 1, characterized in that: The temperature measurement ranges of the N NTC sensors (1) are continuous as a whole.

3. The NTC-based wide temperature range standard-grade thermometer according to claim 1, characterized in that: The metal shell (2) is made of a material with high thermal conductivity.

4. The NTC-based wide temperature range standard-grade thermometer according to claim 1, characterized in that: Each of the lead wires (3) is respectively wrapped in a corresponding first outer layer; All the leads (3) are wrapped in the same second outer layer (5).

5. The NTC-based wide temperature range standard-grade thermometer according to claim 4, characterized in that: The lead wire (3) is made of a high temperature resistant and corrosion resistant conductive material; The first outer layer and the second outer layer (5) are made of high temperature resistant, flexible and wear-resistant insulating material.

6. The NTC-based wide temperature range standard-grade thermometer according to claim 1, characterized in that: The lead wire (3) is detachably connected to the meter (4) via a connector.

7. A temperature measurement method, using the NTC-based wide temperature range standard-grade thermometer according to any one of claims 1 to 6, characterized in that: The method comprises: S1. In normal mode, when the metal housing contacts the object to be measured, the NTC sensor with the smallest temperature measurement range measures the temperature information of the object to be measured, and transmits the measured temperature information of the object to be measured to the instrument through the lead wire; S2, the instrument determines whether the temperature information exceeds the temperature measurement range of the corresponding NTC sensor; if not, execute S3, if yes, execute S4; S3, the instrument displays the temperature information; S4. The instrument switches to connect to the lead corresponding to the NTC sensor with the next largest temperature measurement range to receive the temperature information measured by the NTC sensor with the next largest temperature measurement range, and returns to execute S2.

8. The temperature measurement method according to claim 7, characterized in that: After S3, the method further includes: S5. During the continuous temperature measurement process, the instrument determines whether the absolute value of the difference between the temperature information measured this time and the temperature information measured last time exceeds a preset range, and the temperature information measured this time is lower than the temperature measurement range of the NTC sensor used for this temperature measurement; if so, execute S6; if not, execute S7; S6, the instrument switches to the lead corresponding to the first target NTC sensor to receive the temperature information measured by it; the temperature measurement range of the first target NTC sensor is smaller than the temperature measurement range of the NTC sensor used for this temperature measurement, and displays it; S7, the instrument determines whether the absolute value of the difference between the temperature information measured this time and the temperature information measured last time exceeds a preset range, and the temperature information measured this time is higher than the temperature measurement range of the NTC sensor used for this temperature measurement; if so, execute S8, if not, execute S9; S8, the instrument switches to the lead corresponding to the second target NTC sensor to receive the temperature information measured by it; the temperature measurement range of the second target NTC sensor is greater than the temperature measurement range of the NTC sensor used for this temperature measurement, and is displayed; S9. The instrument displays the temperature information.

9. The temperature measurement method according to claim 8, characterized in that: The method further comprises: S100, in the self-calibration mode, when the metal housing contacts the calibration object, the instrument sequentially connects the leads corresponding to the two NTC sensors with continuous temperature measurement ranges to sequentially receive the temperature information measured by the two NTC sensors with continuous temperature measurement ranges; the temperature of the calibration object is in the intersection of the temperature measurement ranges of the two NTC sensors with continuous temperature measurement ranges; S200, the instrument determines whether the absolute value of the difference between the two received temperature information is greater than a preset threshold; if not, execute S300, if yes, execute S400; S300, the instrument determines that there is no abnormality in the two NTC sensors used for this temperature measurement; S400: The instrument determines that at least one of the two NTC sensors used for this temperature measurement is abnormal.

10. The temperature measurement method according to claim 9, characterized in that: After S400, the method further includes: S500: The instrument triggers an alarm mechanism.

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