Ultralow-temperature platinum resistor temperature sensor

Abstract

The utility model provides an ultralow temperature platinum resistor temperature sensor, which comprises a temperature sensing assembly and a data transmission assembly, the temperature sensing assembly comprises a first wrapping layer and a protective tube, a platinum resistor is arranged in the first wrapping layer, a welding spot is arranged on the platinum resistor, and the platinum resistor is welded with the data transmission assembly through the welding spot; the data transmission assembly comprises a cable, a shielding layer and a first insulating layer which are sequentially sleeved from inside to outside, and the protection tube is fixedly connected with the data transmission assembly through the pressing ring, so that the low temperature resistance and the interference resistance of the sensor are further improved, and the measurement precision of the temperature sensor is greatly improved; according to the utility model, the data transmission assembly adopts a three-wire structure, so that the influence of lead resistance on a measurement result can be effectively reduced, and the accuracy, the stability and the reliability of temperature measurement are improved to a great extent.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to an ultra-low temperature platinum resistance temperature sensor. Background Art

[0002] Temperature measurement in ultra-low temperature environments is a critical requirement in numerous scientific research fields and industrial applications, particularly in cryogenics, cryogenic physics, aerospace, biomedical engineering, and materials science. Traditional temperature sensors often fail to maintain stability and accuracy in ultra-low temperature conditions. In particular, sensor performance degrades significantly below -100°C, compromising measurement reliability.

[0003] Platinum resistance temperature sensors are widely used for temperature measurement due to their high precision and stability. However, in ultra-low temperature environments, especially near absolute zero, traditional platinum resistance temperature sensors face several key challenges: First, the sensor's main temperature-sensing component may undergo physical changes at extremely low temperatures, affecting the linearity of its resistance value and measurement accuracy; second, the sensor's connecting wires are prone to breakage or poor contact at extremely low temperatures, affecting signal transmission; third, electromagnetic interference and environmental factors interfere with the signal, reducing the sensor's sensitivity and measurement accuracy; and fourth, the resistance of the sensor's connecting wires affects the resistance value of the platinum resistance, causing errors in temperature measurement.

[0004] Therefore, the existing technology needs to be further developed. Utility Model Content

[0005] The purpose of the present invention is to overcome the above technical deficiencies and provide an ultra-low temperature platinum resistance temperature sensor to solve the problems existing in the prior art.

[0006] To achieve the above technical objectives, the present invention provides an ultra-low temperature platinum resistance temperature sensor, comprising a temperature sensing component and a data transmission component, including:

[0007] The temperature sensing component includes a first wrapping layer and a protective tube, a platinum resistor is provided in the first wrapping layer, a welding point is provided on the platinum resistor, and the platinum resistor is welded to the data transmission component through the welding point;

[0008] The data transmission component includes a cable, a shielding layer and a first insulating layer which are sequentially sleeved from the inside to the outside, and the protective tube is fixedly connected to the data transmission component via a pressure ring.

[0009] Specifically, the welding point includes a first welding point and a second welding point, one end of the platinum resistor is provided with a first welding point, and the other end of the platinum resistor is provided with a second welding point, the cable includes a first cable, a second cable and a third cable, the first cable and the second cable are respectively welded to the first welding point, and the third cable is welded to the second welding point.

[0010] Specifically, the first cable includes a first inner core wire and a second insulation layer, the second cable includes a second inner core wire and a second insulation layer, and the third cable includes a third inner core wire and a second insulation layer. One end of the platinum resistor is welded to the first inner core wire and the second inner core wire respectively through a first welding point, and the other end of the platinum resistor is welded to the third inner core wire through a second welding point.

[0011] Specifically, the data transmission component and the platinum resistor are welded by laser.

[0012] Specifically, any one of the first welding point and the second welding point is wrapped by a Teflon heat shrink tube.

[0013] Specifically, the platinum resistor and the solder joint are wrapped with polyimide tape at the same time to form a first wrapping layer.

[0014] Specifically, the first wrapping layer and part of the data transmission component are encapsulated in a protective tube, and the length of the part of the data transmission component encapsulated in the protective tube is greater than or equal to 10 mm.

[0015] Specifically, the first insulating layer and the second insulating layer are both made of PFA insulating material, and the shielding layer is a copper wire braided shielding layer.

[0016] Specifically, the platinum resistor is a Class A precision PT100 platinum resistor, and the diameter of the Teflon heat shrink tube is 1.5 mm.

[0017] Specifically, the protective tube is a stainless steel protective tube, and the diameter of the stainless steel protective tube is 4 mm ± 0.1 mm.

[0018] Beneficial effects:

[0019] The utility model includes a temperature sensing component and a data transmission component. The temperature sensing component includes a first wrapping layer and a protective tube. A platinum resistor is arranged in the first wrapping layer. The platinum resistor is welded to the data transmission component through welding points. The data transmission component includes a cable, a first insulating layer, a shielding layer and a second insulating layer sequentially arranged from the inside to the outside, which further improves the low-temperature resistance and anti-interference performance of the sensor and greatly improves the measurement accuracy of the temperature sensor. At the same time, the data transmission component in the utility model adopts a three-wire structure, which can effectively reduce the influence of the wire resistance on the measurement results, and greatly improves the accuracy, stability and reliability of the temperature measurement of the utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a structure schematic view of the outside of the super-low-temperature platinum resistance temperature sensor provided in the embodiment of the utility model;

[0021] Figure 2 is a structure schematic view of the temperature sensing assembly of the super-low-temperature platinum resistance temperature sensor provided in the embodiment of the utility model;

[0022] Among them, the above-mentioned drawing includes the following figure marks:

[0023] 2, temperature sensing assembly; 3, data transmission assembly; 4, compression ring; 5, second cable; 6, first wrapping layer; 7, first cable; 8, third cable; 9, second welding point; 10, first welding point; 11, platinum resistance; 12, Teflon heat shrink tube; 13, polyimide adhesive tape; 14, protective tube; 15, first inner core wire; 16, second inner core wire; 17, third inner core wire. DETAILED DESCRIPTION

[0024] In order to make the personnel in the art better understand the technical scheme of the utility model, the technical scheme of the utility model is described clearly and completely below in combination with the drawings of the utility model, based on the embodiments in the present application, other similar embodiments obtained by the person skilled in the art without making creative labor should belong to the protection scope of the present application.In addition, the direction words mentioned in the following embodiments, such as "up", "down", "left", "right" and the like are only the direction of the drawing, therefore, the direction words used are used to explain but not limit the utility model creation.

[0025] The utility model is further described below in combination with the drawings and preferred embodiments.

[0026] Please refer to Figure 1 and Figure 2 , the embodiment provides a kind of super-low-temperature platinum resistance temperature sensor, including temperature sensing assembly 2 and data transmission assembly 3, including:

[0027] The temperature sensing assembly 2 includes first wrapping layer 6 and protective tube 14, the first wrapping layer 6 is provided with platinum resistance 11, the platinum resistance 11 is provided with welding point, and the platinum resistance 11 is welded with data transmission assembly 3 by welding point;

[0028] The data transmission assembly 3 includes cable, shielding layer and first insulating layer sequentially sleeved from inside to outside, and the protective tube 14 is fixedly connected with data transmission assembly 3 by compression ring 4.

[0029] It can be understood that the temperature sensing component 2 of the present invention is the core component for directly sensing and measuring temperature, and the data transmission component 3 is used to transmit the measured temperature information to the data processing system or display device. Among them, the temperature coefficient of the platinum resistor 11 in the temperature sensing component 2 is close to linear growth, and its resistance changes significantly with the change of temperature. It has the characteristics of corrosion resistance and non-oxidation. Therefore, it is not easily affected by the external environment during use and causes short circuit or open circuit, which greatly improves the stability of temperature measurement. The data transmission component 3 is a data transmission connecting line, which adopts a sheathed wire with two layers of insulation inside and outside. The inner layer of the sheathed wire is also provided with a copper wire braided shielding layer, which further improves the anti-interference ability of data transmission and greatly improves the measurement accuracy of the sensor.

[0030] Specifically, the welding point includes a first welding point 10 and a second welding point 9, one end of the platinum resistor 11 is provided with a first welding point 10, and the other end of the platinum resistor 11 is provided with a second welding point 9, the cable includes a first cable 7, a second cable 5 and a third cable 8, the first cable 7 and the second cable 5 are respectively welded to the first welding point 10, and the third cable 8 is welded to the second welding point 9.

[0031] It is understandable that because the platinum resistor 11 is extremely sensitive to temperature feedback, the conductor resistance of the data transmission cable itself will also affect its resistance value. The data transmission assembly 3 of the platinum resistance temperature sensor in the present invention uses a three-wire structure, in which two cables, namely the first cable 7, the second cable 5, and one pin of the platinum resistor 11, are welded together to form a bridge with another cable, namely the third cable 8. During measurement, the third cable is used to read the resistance value and forms part of the bridge circuit with the two parallel leads. Because the resistance of the third cable 8 is not in parallel with the measured resistor, its resistance change does not directly affect the measured resistance value. This three-wire structure can effectively compensate and correct for the uncertainty of the data transmission cable resistance. Especially in long-distance signal transmission or in applications with high precision requirements, this design can significantly improve the accuracy and stability of temperature measurement, greatly enhancing the test accuracy of the temperature sensor. It should be noted that the present invention does not impose any further restrictions on the colors of the first cable 7, the second cable 5, and the third cable 8. It only needs to ensure that the first cable 7, the second cable 5, and the third cable 8 are distinguishable.

[0032] Specifically, the first cable 7 includes a first inner core wire 15 and a second insulation layer, the second cable 5 includes a second inner core wire 16 and a second insulation layer, the third cable 8 includes a third inner core wire 17 and a second insulation layer, one end of the platinum resistor 11 is welded to the first inner core wire 15 and the second inner core wire 16 through a first welding point 10, and the other end of the platinum resistor 11 is welded to the third inner core wire 17 through a second welding point 9.

[0033] It should be further explained that all three cables include a second insulation layer, that is, the inner insulation of the data transmission component 3, which is directly wrapped around the outer layer of the inner core wire to provide the first layer of insulation protection, ensuring that the inner core wire is isolated from the external dielectric, thereby preventing current leakage, protecting the conductor from environmental influences, and further improving the security and stability of data transmission.

[0034] Specifically, the data transmission component 3 and the platinum resistor 11 are welded by laser.

[0035] It can be understood that the data transmission component 3 extends into the inside of the protective tube 14 and is laser welded to the platinum resistor 11. Laser welding is a high-energy-density welding technology that uses a laser beam to heat and melt the workpiece, and then forms a connection in the molten pool. Compared with traditional welding methods, laser welding has a high energy density and can directly melt the weld metal, so that the platinum resistor and the wire are tightly and firmly welded together.

[0036] Specifically, any one of the first welding point 10 and the second welding point 9 is wrapped by a Teflon heat shrink tube 12 .

[0037] It should be noted that the Teflon heat shrink tube 12 wraps one of the welding points to separate it from the other welding point, thereby playing an insulating role.

[0038] Specifically, the platinum resistor 11 and the solder joint are wrapped with the polyimide tape 13 at the same time, thereby forming the first wrapping layer 6 .

[0039] It can be understood that the platinum resistor 11, the solder joints, the cables not wrapped by the shielding layer and the first insulating layer, and part of the data transmission component 3 are wrapped together with the polyimide tape 13 to form the first wrapping layer 6. The polyimide tape 13 is one of the organic polymer materials with the best comprehensive performance. It is resistant to high temperatures of more than 400°C and has a long-term operating temperature range of -200 to 300°C. Wrapping all the platinum resistor leads and solder joints is to insulate the solder joints from the outside world. It has good stability and greatly improves the insulation and electrical performance of the product.

[0040] Specifically, the first wrapping layer 6 and part of the data transmission component 3 are encapsulated in a protective tube 14 , and the length of the part of the data transmission component 3 encapsulated in the protective tube 14 is greater than or equal to 10 mm.

[0041] It should be noted here that the first wrapping layer 6 and the data transmission component 3 partially extended to the protective tube are encapsulated in the protective tube 14. The protective tube 14 is used to extrude the transmission connecting line to play a sealing and fixing role. The length of the data transmission component 3 extended to the protective tube is greater than or equal to 10 mm to ensure that in an extremely low temperature environment, the connecting line has sufficient mechanical strength and flexibility to avoid embrittlement and breakage caused by temperature changes. In addition, the longer connecting line can provide a certain space, which helps to reduce the measurement error caused by the temperature gradient and ensure the response speed and accuracy of the sensor.

[0042] Specifically, the first insulating layer and the second insulating layer are both made of PFA insulating material, and the shielding layer is a copper wire braided shielding layer.

[0043] Furthermore, the insulation layer is made of PFA insulation material, which has good low-temperature resistance and can still bend without breaking in an ultra-low temperature environment of -100°C. The shielding layer is a copper wire braided shielding layer with strong anti-interference ability. The sensor can filter out the surrounding electromagnetic interference, thereby making the sensor temperature measurement more accurate.

[0044] Specifically, the platinum resistor 11 is a PT100 platinum resistor with Class A precision, and the diameter of the Teflon heat shrink tube 12 is 1.5 mm.

[0045] Furthermore, the Class A precision PT100 platinum resistor has a resistance of 100 ohms at 0°C and approximately 138.5 ohms at 100°C. Its resistance increases uniformly with rising temperature, with measurement accuracy to ±0.15°C, further improving temperature measurement stability. The diameter of the Teflon heat shrink tubing 12 is 1.5mm, ensuring it tightly wraps around the solder joints of the platinum resistor 11, providing excellent electrical insulation and mechanical protection. Teflon tubing can withstand temperatures as low as -200°C and has excellent chemical stability and corrosion resistance, making it one of the most corrosion-resistant materials in the world.

[0046] Specifically, the protection tube 14 is a stainless steel protection tube, and the diameter of the stainless steel protection tube is 4 mm ± 0.1 mm.

[0047] It can be understood that the stainless steel protective tube with a diameter of 4mm±0.1mm has the characteristics of strong corrosion resistance and good thermal conductivity, is easy to process, has high dimensional control precision, and is convenient to install and use. The stainless steel tube undergoes an annealing heat treatment process, which heats the stainless steel to a certain temperature, maintains it for a certain period of time, and then slowly cools it to change its internal structure and improve its mechanical and physical properties. After annealing, the internal stress generated during the processing is eliminated, the plasticity and toughness of the material are improved, and the stainless steel tube is ensured not to break during the ring pressing process. It can fully extrude the wires and fit tightly to the wires to play a sealing and fixing role.

[0048] It should be noted here that the present invention includes a temperature sensing component and a data transmission component. The temperature sensing component includes a first wrapping layer and a protective tube. A platinum resistor is arranged in the first wrapping layer. The platinum resistor is welded to the data transmission component through welding points. The data transmission component includes a cable, a first insulation layer, a shielding layer and a second insulation layer arranged in sequence from the inside to the outside, which further improves the sensor's low-temperature resistance and anti-interference performance, and greatly improves the measurement accuracy of the temperature sensor. At the same time, the data transmission component in the present invention adopts a three-wire structure, which can effectively reduce the influence of wire resistance on the measurement results, and greatly improves the accuracy, stability and reliability of the temperature measurement of the present invention.

[0049] The various technical features described above can be combined arbitrarily. Although not all possible combinations of these technical features are described, any combination of these technical features should be considered to be covered by this specification as long as such combination does not conflict.

[0050] The specific embodiments of the present invention described above do not limit the scope of protection of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. An ultra-low temperature platinum resistance temperature sensor, comprising a temperature sensing component (2) and a data transmission component (3), characterized in that: include: The temperature sensing component (2) comprises a first wrapping layer (6) and a protective tube (14); a platinum resistor (11) is provided in the first wrapping layer (6); a welding point is provided on the platinum resistor (11); and the platinum resistor (11) is welded to the data transmission component (3) via the welding point; The data transmission component (3) comprises a cable, a shielding layer and a first insulating layer which are sequentially sleeved from the inside out, and the protective tube (14) is fixedly connected to the data transmission component (3) via a pressure ring (4); The welding point includes a first welding point (10) and a second welding point (9), one end of the platinum resistor (11) is provided with the first welding point (10), and the other end of the platinum resistor (11) is provided with the second welding point (9), the cables include a first cable (7), a second cable (5) and a third cable (8), the first cable (7) and the second cable (5) are respectively welded to the first welding point (10), and the third cable (8) is welded to the second welding point (9); The data transmission component (3) and the platinum resistor (11) are welded by laser.

2. The ultra-low temperature platinum resistance temperature sensor according to claim 1, characterized in that: The first cable (7) includes a first inner core wire (15) and a second insulating layer, the second cable (5) includes a second inner core wire (16) and a second insulating layer, the third cable (8) includes a third inner core wire (17) and a second insulating layer, one end of the platinum resistor (11) is welded to the first inner core wire (15) and the second inner core wire (16) via a first welding point (10), and the other end of the platinum resistor (11) is welded to the third inner core wire (17) via a second welding point (9).

3. The ultra-low temperature platinum resistance temperature sensor according to claim 2, characterized in that: Any one of the first welding point (10) and the second welding point (9) is wrapped by a Teflon heat shrink tube (12).

4. The ultra-low temperature platinum resistance temperature sensor according to claim 1, characterized in that: The platinum resistor (11) and the solder joint are simultaneously wrapped with a polyimide tape (13) to form a first wrapping layer (6).

5. The ultra-low temperature platinum resistance temperature sensor according to claim 4, characterized in that: The first wrapping layer (6) and a portion of the data transmission component (3) are encapsulated in a protective tube (14), and the length of the portion of the data transmission component (3) encapsulated in the protective tube (14) is greater than or equal to 10 mm.

6. The ultra-low temperature platinum resistance temperature sensor according to claim 1, characterized in that: The first insulating layer and the second insulating layer are both made of PFA insulating material, and the shielding layer is a copper wire braided shielding layer.

7. The ultra-low temperature platinum resistance temperature sensor according to claim 3, characterized in that: The platinum resistor (11) is a Class A precision PT100 platinum resistor, and the diameter of the Teflon heat shrink tube (12) is 1.5 mm.

8. The ultra-low temperature platinum resistance temperature sensor according to claim 1, characterized in that: The protective tube (14) is a stainless steel protective tube, and the diameter of the stainless steel protective tube is 4 mm ± 0.1 mm.

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