Device for improving thermal resistance measurement precision and manufacturing method thereof

Abstract

The invention discloses a device for improving the measurement precision of a thermal resistor and a manufacturing method thereof, and belongs to the technical field of power equipment, and the device for improving the measurement precision of the thermal resistor comprises a signal line, a temperature measuring sheet, a supporting rod and a heat shrink tube. Wherein one surface of the temperature measuring sheet is a connecting surface, and the other surface is a detection surface; one end of the signal line directly faces the connecting surface and is connected with the connecting surface, and the supporting rod extends in parallel to the signal line and is connected with the connecting surface; the signal line and the supporting rod are jointly arranged in the heat shrink tube in a penetrating mode, and the heat shrink tube can shrink in the radial direction of the heat shrink tube when heated so as to wrap the signal line and the supporting rod. The manufacturing method of the device for improving the measurement precision of the thermal resistor is applied to the device for improving the measurement precision of the thermal resistor. Through cooperation of the signal line, the temperature measuring sheet, the supporting rod and the heat shrink tube, the problem that in the prior art, due to thermal expansion of all layers of materials of a cable, aperture damage and the like, a thermal resistor cannot be in close contact with a temperature measuring point, and consequently measurement errors are generated is effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric power equipment, and in particular to a device for improving the measurement accuracy of thermal resistors and a manufacturing method thereof. Background Art

[0002] In the field of power transmission, the normal operation of cables is crucial to ensuring the stability and safety of power supply. Among them, the temperature of cable conductors is a key indicator reflecting their operating status.

[0003] At present, the detection of cable conductor temperature mainly relies on obtaining the thermal parameters of each layer of the cable and combining it with the IEC standard for temperature inversion. As the cable operation time increases, the parameters of each layer of the cable change dynamically and need to be recalibrated. The recalibration of thermal parameters relies on thermal resistance temperature measurement technology, which measures the temperature based on the characteristic that the resistance value of the temperature measurement chip increases with the increase of temperature. In specific operation, the temperature measurement chip senses the temperature change by contacting a specific part of the cable, and converts the temperature signal into an electrical signal for transmission and processing.

[0004] However, the existing conventional thermal resistor temperature measurement technology has many defects. On the one hand, during the cable temperature rise test, due to the thermal expansion characteristics of the cable materials, the thermal resistor and the temperature measurement point cannot always maintain close contact, resulting in measurement errors. On the other hand, the operation of drilling holes in different cable materials to lay thermal resistors in order to obtain the measured thermal parameters will not only destroy other apertures, but also the thermal resistor itself has a relatively soft structure. When the cable aperture moves slightly due to the presence of the buffer layer, it is difficult for the thermal resistor to reach the specified position, making it difficult for the thermal resistor to accurately and closely contact the temperature measurement point, which will also lead to measurement errors. Summary of the invention

[0005] The purpose of the present invention is to provide a device for improving the measurement accuracy of thermal resistors and a method for making the same, so as to solve the technical problem in the prior art that during the temperature measurement of a cable conductor, due to reasons such as thermal expansion of the material and external force, the thermal resistor and the temperature measuring point cannot always maintain close contact, thereby causing measurement errors.

[0006] As conceived above, the technical solution adopted by the present invention is:

[0007] In one aspect, the present invention provides a device for improving the measurement accuracy of a thermal resistor, comprising:

[0008] Signal line;

[0009] A temperature measuring piece, one side of the temperature measuring piece is a connection surface, and the other side is a detection surface; one end of the signal line is directly facing the connection surface and connected to the connection surface,

[0010] A support rod extending parallel to the signal line and connected to the connection surface;

[0011] A heat shrink tube, wherein the signal line and the support rod are both passed through the heat shrink tube, and the heat shrink tube can shrink along its own radial direction when heated, so as to cover the signal line and the support rod.

[0012] Preferably, the angle between the temperature measuring piece and the signal line is 90 degrees.

[0013] Preferably, the detection surface is coated with silver silicone grease.

[0014] Preferably, the outer periphery of the signal line is covered with an insulating layer.

[0015] Preferably, the support rod is made of insulating material.

[0016] Preferably, the support rod is a plastic rod.

[0017] On the other hand, the present invention also provides a method for manufacturing a device for improving the measurement accuracy of a thermal resistor, which is applied to the above-mentioned device for improving the measurement accuracy of a thermal resistor, comprising:

[0018] Bend a portion of the temperature measuring sheet and make the connecting surface face one end of the signal line;

[0019] Connecting one end of the signal line to the connection surface, and connecting one end of the support rod to the connection surface;

[0020] The heat shrink tube is axially sleeved on the signal line and the support rod;

[0021] The outer periphery of the heat shrink tube is uniformly heated so that the heat shrink tube shrinks along its own radial direction and covers the signal line and the support rod.

[0022] Preferably, the support rod and the connecting surface are bonded by a fixing colloid.

[0023] Preferably, after the support rod is bonded, the resistance of the detection surface is measured and recorded as the first resistance; the resistance of the connection surface is measured and recorded as the second resistance. If the difference between the first resistance and the second resistance is greater than the rated resistance, the fixed colloidal impurities on the connection surface are removed.

[0024] Preferably, when heating the heat shrink tube, heating is performed from the middle to both ends of the heat shrink tube.

[0025] Beneficial effects of the present invention:

[0026] The device for improving the measurement accuracy of thermal resistors proposed by the present invention ensures the stability and accuracy of signal transmission by making the signal line face the connection surface. Secondly, by setting the support rod to be connected to the connection surface, on the one hand, the rigidity of the support rod can limit the displacement of the temperature measuring plate, so that it is not easy to deviate from the temperature measuring point under the condition of thermal expansion, etc., and maintain a relatively stable position. On the other hand, the stress applied by the support rod can make the metal sheet fit the measurement point more closely, even if the material of each layer of the cable undergoes thermal expansion or slight displacement, it can ensure that the metal sheet and the measurement point maintain good contact, increase the contact area between the temperature measuring plate and the temperature measuring point, thereby improving the accuracy and stability of the measurement. In addition, by utilizing the characteristics of the low melting point and high adhesion of the inner layer of the heat shrink tube, the heat shrink tube is heated to shrink it, thereby integrating the support rod and the signal line, enhancing the stability and integrity of the overall structure, avoiding the thermal expansion of the material during the temperature rise of the cable and the slight displacement of the aperture when the cable is drilled, which affects the temperature measurement accuracy, and improving the measurement accuracy of the thermal resistor. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of a device for improving the measurement accuracy of thermal resistance provided by the first embodiment of the present invention;

[0028] Figure 2 It is a front view of a device for improving the measurement accuracy of thermal resistance provided by the first embodiment of the present invention;

[0029] Figure 3 It is a side view of a device for improving the measurement accuracy of thermal resistance provided by the first embodiment of the present invention;

[0030] Figure 4 It is a top view of a device for improving the measurement accuracy of thermal resistors provided in Embodiment 1 of the present invention.

[0031] In the figure:

[0032] 1. Signal line; 2. Temperature measuring piece; 21. Connection surface; 22. Detection surface; 3. Support rod; 4. Heat shrink tube; 5. Fixing colloid. DETAILED DESCRIPTION

[0033] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0034] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0036] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0037] Embodiment 1

[0038] See also Figures 1 to 4 The device for improving the measurement accuracy of thermal resistors provided by the embodiment of the present invention comprises a signal line 1, a temperature measuring piece 2, a support rod 3 and a heat shrink tube 4. Among them, one side of the temperature measuring piece 2 is a connection surface 21, and the other side is a detection surface 22; one end of the signal line 1 is directly opposite to the connection surface 21 and connected to the connection surface 21, and the support rod 3 extends parallel to the signal line 1 and is connected to the connection surface 21; the signal line 1 and the support rod 3 are jointly arranged in the heat shrink tube 4, and the heat shrink tube 4 can shrink along its own radial direction when heated, so as to cover the signal line 1 and the support rod 3.

[0039] The device for improving the measurement accuracy of thermal resistor proposed by the present invention increases the contact area between the two by making the signal line 1 face the connection surface 21, thereby ensuring the stability and accuracy of signal transmission. Secondly, by setting the support rod 3 to be connected with the connection surface 21, on the one hand, the rigidity of the support rod 3 can limit the displacement of the temperature measuring plate 2, so that it is not easy to deviate from the temperature measuring point under the condition of thermal expansion, etc., and maintain a relatively stable position. On the other hand, the stress applied by the support rod 3 can make the metal sheet fit the measuring point more closely, and even in the case of thermal expansion or slight displacement of the materials in each layer of the cable, it can ensure that the metal sheet and the measuring point maintain good contact, thereby improving the accuracy and stability of the measurement. In addition, by utilizing the low melting point and high adhesiveness of the inner layer of the heat shrink tube 4, the heat shrink tube 4 is heated to shrink it, thereby integrating the support rod 3 and the signal line 1, enhancing the stability and integrity of the overall structure, and avoiding the thermal expansion of the material during the temperature rise of the cable and the slight displacement of the aperture when the cable is drilled.

[0040] The specific structure of the device for improving the measurement accuracy of thermal resistance is described below.

[0041] The outer periphery of the signal line 1 is coated with an insulating layer, which can effectively prevent the signal line 1 from being interfered with by external electromagnetic interference during the signal transmission process, and ensure the stability and accuracy of signal transmission. At the same time, the insulating layer can prevent the signal line 1 from short-circuiting with other surrounding components or external conductors, thereby improving the electrical safety of the entire device. In addition, the insulating layer can also play a certain protective role on the signal line 1, reduce the damage to the signal line 1 caused by wear, scratches, etc., and extend the service life of the signal line 1, thereby enhancing the reliability and durability of the entire device.

[0042] In this embodiment, two signal lines 1 are provided, and the signal line 1 adopts a multi-strand twisted copper core wire, and the diameter of each copper core wire is 0.1 mm. The copper core wires are coated with a polyvinyl chloride (PVC) insulation layer with a thickness of 0.2 mm. The multi-strand twisted structure increases the flexibility of the signal line 1, so that it can better adapt to the complex environment and possible bending conditions inside the cable.

[0043] The temperature measuring piece 2 acts as a thermal resistor in the device, which is used to sense temperature changes and convert them into electrical signals for transmission and measurement. In this embodiment, the temperature measuring piece 2 uses a thin film resistor, and both sides of the temperature measuring piece 2 can detect temperature. For the convenience of the following description, one side of the temperature measuring piece 2 is defined as a connection surface 21 for connecting other devices; the other side is defined as a detection surface 22 for measuring temperature.

[0044] Specifically, the angle between the temperature measuring piece 2 and the signal line 1 is 90 degrees. Setting the angle between the temperature measuring piece 2 and the signal line 1 to 90 degrees can make the connection between the signal line 1 and the temperature measuring piece 2 more stable, and reduce the loose connection or unstable signal transmission caused by improper angles. The right-angle connection method is conducive to maintaining the regularity of the structure, which is more convenient during installation and use, and reduces the difficulty of installation and the possibility of errors.

[0045] More specifically, the detection surface 22 is coated with silver silicone grease. Silver silicone grease has good thermal conductivity and can accelerate heat transfer between the detection surface 22 and the temperature measuring point, thereby sensing temperature changes more quickly and accurately and improving the response speed and accuracy of temperature measurement. Secondly, silver silicone grease can fill the tiny gap between the detection surface 22 and the temperature measuring point, further enhancing the tightness of the contact, reducing thermal resistance, and ensuring the accuracy and stability of temperature measurement. In addition, silver silicone grease also has a certain lubricating effect, which helps to reduce the friction between the detection surface 22 and the temperature measuring point during installation and use, reduce wear, and extend the service life of the device.

[0046] The support rod 3 is used to limit the displacement of the temperature measuring piece 2 and at the same time apply stress to the temperature measuring piece 2 so that it is not easy to deviate from the temperature measuring point and maintain a relatively stable position when the cable temperature rises and causes thermal expansion or there are other external forces.

[0047] Specifically, the support rod 3 is made of insulating material. This can effectively prevent the current from being conducted through the support rod 3, avoid possible leakage or short circuit, and improve the electrical safety of the device. Secondly, the insulating material can reduce the interference of the support rod 3 on the signal transmitted by the signal line 1, ensuring the stability and accurate transmission of the signal. Furthermore, the insulated support rod 3 will not generate additional heat or electromagnetic effects due to conduction during the operation of the cable, which helps to maintain the stability of the internal temperature of the cable and reduce heat loss.

[0048] In this embodiment, the support rod 3 is a plastic rod. Plastic has good insulation properties and can reliably avoid current conduction and signal interference. Secondly, plastic materials are usually light in weight, which helps to reduce the weight of the entire device and facilitates installation and transportation. In addition, plastic costs are relatively low and are easy to process and shape, which can reduce the cost of production and improve production efficiency.

[0049] In other embodiments, the support rod 3 may also be a ceramic rod, a fiberglass rod, a wooden rod, etc., which is not limited here.

[0050] It is worth noting that when selecting the support rod 3, the diameter of the support rod 3 needs to be adaptively selected according to the effective area of ​​the temperature measuring piece 2, so as to reduce the influence of the thermal expansion of the material on the contact area between the thermal resistor and the temperature measuring point. In addition, the length of the support rod 3 needs to be adjusted according to the requirements of the temperature measuring point depth of each layer of the cable material, so as to ensure that the temperature measuring piece 2 is in close contact with the temperature measuring point.

[0051] Embodiment 2

[0052] The embodiment of the present invention further provides a method for manufacturing a device for improving the measurement accuracy of a thermal resistor, which is applied to the above-mentioned device for improving the measurement accuracy of a thermal resistor, and the specific steps include:

[0053] Bend part of the temperature measuring piece 2 so that the connecting surface 21 faces one end of the signal line 1;

[0054] In this step, tweezers are used to bend part of the temperature measuring piece 2 so that the angle between part of the temperature measuring piece 2 and the signal line 1 is 90 degrees.

[0055] Connect one end of the signal line 1 to the connection surface 21, and connect one end of the support rod 3 to the connection surface 21;

[0056] The heat shrink tube 4 is axially sleeved on the signal line 1 and the support rod 3;

[0057] The outer circumference of the heat shrink tube 4 is uniformly heated, so that the heat shrink tube 4 shrinks along its own radial direction and covers the signal line 1 and the support rod 3 .

[0058] Specifically, the support rod 3 and the connection surface 21 are bonded by the fixing colloid 5. The fixing colloid 5 can achieve uniform and comprehensive bonding, ensure that the connection between the support rod 3 and the connection surface 21 is tight and stable, avoid loosening or separation during use, and thus enhance the overall stability of the device. Moreover, compared with other connection methods, such as welding or mechanical connection, the bonding method is simpler to operate and easy to implement, which can improve production efficiency and reduce production costs.

[0059] The fixing colloid 5 may be made of existing epoxy resin glue, silicone glue or polyurethane glue, etc., which is not limited here.

[0060] More specifically, in order to ensure that there are no impurities of the fixed colloid 5 on the detection surface 22 and the temperature measurement point of the temperature measuring piece 2, after the support rod 3 is bonded, the resistance of the detection surface 22 is measured and recorded as the first resistance; the resistance of the connection surface 21 is measured and recorded as the second resistance. If the difference between the first resistance and the second resistance is greater than the rated resistance, the impurities of the fixed colloid 5 on the connection surface 21 are removed. When the difference between the first resistance and the second resistance is less than or equal to the rated resistance, it indicates that there are no impurities of the fixed colloid 5 at the detection surface 22 and the temperature measurement point.

[0061] In addition, when heating the heat shrink tube 4, the heat is heated from the middle to both ends of the heat shrink tube 4, thereby ensuring that the heat shrink tube 4 shrinks more evenly. Starting from the middle, the heat is transferred to both ends, so that the shrinkage degree of each part of the heat shrink tube 4 during the shrinkage process is more consistent, avoiding the situation of excessive or insufficient local shrinkage, thereby improving the wrapping quality and tightness of the heat shrink tube 4 on the signal line 1 and the support rod 3. The uniform heat distribution can make the air inside the heat shrink tube 4 discharge more smoothly, reduce the possibility of bubble formation, and enhance the protective performance and sealing effect of the heat shrink tube 4.

[0062] In this embodiment, the heat shrink tube 4 is heated by an operator holding a hot air gun. In other embodiments, the heat may also be heated by an industrial oven, an infrared heating lamp or other equipment, which is not limited here.

[0063] The above embodiments are only to illustrate the basic principles and characteristics of the present invention. The present invention is not limited by the above embodiments. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and modifications, which are within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A device for improving the measurement accuracy of thermal resistance, characterized in that: include: Signal line (1); A temperature measuring piece (2), one side of the temperature measuring piece (2) being a connection surface (21) and the other side being a detection surface (22); one end of the signal line (1) facing the connection surface (21) and being connected to the connection surface (21); A support rod (3) extending parallel to the signal line (1) and connected to the connection surface (21); A heat shrink tube (4), wherein the signal line (1) and the support rod (3) are inserted into the heat shrink tube (4) together, and the heat shrink tube (4) can shrink along its own radial direction when heated, thereby covering the signal line (1) and the support rod (3).

2. The device for improving the measurement accuracy of thermal resistance according to claim 1, characterized in that: The angle between the temperature measuring piece (2) and the signal line (1) is 90 degrees.

3. The device for improving the measurement accuracy of thermal resistance according to claim 1, characterized in that: The detection surface (22) is coated with silver silicone grease.

4. The device for improving the measurement accuracy of thermal resistance according to claim 1, characterized in that: The outer periphery of the signal line (1) is covered with an insulating layer.

5. The device for improving the measurement accuracy of thermal resistance according to claim 1, characterized in that: The support rod (3) is made of insulating material.

6. The device for improving the measurement accuracy of thermal resistance according to claim 5, characterized in that: The support rod (3) is a plastic rod.

7. A method for manufacturing a device for improving the measurement accuracy of thermal resistance, characterized in that: The device for improving the measurement accuracy of thermal resistance as claimed in any one of claims 1 to 6 comprises: Bend a portion of the temperature measuring sheet (2) so that the connecting surface (21) faces one end of the signal line (1); Connecting one end of the signal line (1) to the connection surface (21), and connecting one end of the support rod (3) to the connection surface (21); The heat shrink tube (4) is sleeved on the signal line (1) and the support rod (3) along the axial direction; The outer periphery of the heat shrink tube (4) is uniformly heated, so that the heat shrink tube (4) shrinks along its own radial direction and covers the signal line (1) and the support rod (3).

8. The method for manufacturing a device for improving the measurement accuracy of thermal resistance according to claim 7, characterized in that: The support rod (3) and the connection surface (21) are bonded together via a fixing colloid (5).

9. The method for manufacturing a device for improving the measurement accuracy of thermal resistance according to claim 8, characterized in that: After the support rod (3) is bonded, the resistance value of the detection surface (22) is measured and recorded as the first resistance value; the resistance value of the connection surface (21) is measured and recorded as the second resistance value; if the difference between the first resistance value and the second resistance value is greater than the rated resistance value, the impurities of the fixed colloid (5) on the connection surface (21) are removed.

10. The method for manufacturing a device for improving thermal resistance measurement accuracy according to claim 7, characterized in that: When the heat shrink tube (4) is heated, the heat is applied from the middle portion to both ends of the heat shrink tube (4).

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