Temperature sensing assembly precision debugging method based on superfine resistance wire

Abstract

The invention relates to the technical field of temperature sensing assemblies, and discloses a temperature sensing assembly precision debugging method based on a superfine resistance wire, and the method comprises the steps: taking two strands of resistance wires as a temperature sensing assembly, winding the temperature sensing assembly on a skeleton, dispensing conductive slurry between the two strands of resistance wires, and sintering and solidifying the conductive slurry to form a stable short-circuit debugging point; and carrying out precision test on the temperature sensing assembly in an environment of 0 DEG C, and judging whether the resistance of the resistance wire at the temperature sensing end meets the resistance value requirement of the corresponding division value or not at 0 DEG C. Compared with an original process method that the length of the resistance wire is gradually trimmed and then debugging nodes are formed in a welding mode, the process method that the resistance wire is in short circuit connection with the conductive slurry so as to reduce the resistance value output in a loop is adopted, and the controllability of the resistance value of the temperature sensing assembly in the debugging process and the debugging operability are greatly improved; especially in the case of debugging the superfine resistance wire, the debugging qualification rate and the debugging efficiency can also be greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of temperature sensing components and discloses a temperature sensing component precision debugging method based on ultra-fine resistance wires. Background Art

[0002] The working principle of thermistor sensor is to measure temperature based on the property that the resistance of metal conductor increases with the increase of temperature. Among them, platinum thermistor has the highest measurement accuracy. In addition to platinum wire, other metal thermistor materials used for industrial measurement include copper, nickel, etc.

[0003] With the vigorous development of the thermal resistor sensor industry, new models of various structural forms have been applied, and they are gradually developing towards miniaturization and micro-miniaturization, which will inevitably lead to the gradual increase in the difficulty of assembly and debugging. The output characteristics of each thermal resistor sensor must meet a specific graduation value, such as PT100 graduation, PT1000 graduation, etc. In order to make the temperature sensing component of the sensor meet the specific graduation value, it must be achieved through precision debugging of the processing and manufacturing process. The essence of precision debugging is to continuously and accurately adjust the length of the resistance wire in the circuit. The process of adjusting the length of the resistance wire is the key link of precision debugging.

[0004] The traditional precision debugging methods of thermistor sensor temperature sensing components mainly include two types of process methods: trimming the resistance wire through specific instruments and melting the resistance wire through high heat, so as to achieve the ultimate goal of adjusting the length of the resistance wire connected to the loop. This makes the precision debugging process of the traditional process method irreversible, which directly affects the precision debugging pass rate of the component. Summary of the invention

[0005] The purpose of the present invention is to provide a method for precision debugging of a temperature sensing component based on an ultra-fine resistance wire, which has strong controllability and operability during the debugging process, and has the advantages of a wide range of applications and a high pass rate.

[0006] In order to achieve the above technical effects, the technical solution adopted by the present invention is:

[0007] A method for adjusting the accuracy of a temperature sensing component based on an ultra-fine resistance wire, comprising:

[0008] The two strands of resistance wire are electrically connected to the lead wires respectively, and the two strands of resistance wire are wound around the frame as temperature sensing components;

[0009] The conductive slurry is dotted between two strands of resistance wire, and the temperature sensing component with the conductive slurry is placed in a high-temperature furnace. According to the sintering temperature characteristics of the conductive slurry, the conductive slurry is sintered and solidified to form a stable short-circuit debugging point;

[0010] After the conductive paste is sintered, the temperature sensing component is tested for accuracy in a 0°C environment. If the resistance of the temperature sensing end resistor wire at 0 degrees Celsius meets the resistance value requirement of the corresponding graduation value, the debugging is completed; otherwise, the spot coating position is changed, and the conductive paste is sintered and solidified to form a new short-circuit debugging point until the resistance of the temperature sensing end resistor wire at 0 degrees Celsius meets the resistance value requirement of the corresponding graduation value.

[0011] Furthermore, the skeleton is made of ceramic material.

[0012] Further, the method of applying the conductive slurry between the two resistance wires includes:

[0013] A stainless steel thin rod with a diameter of Ф0.5mm was selected as a tool for spot coating of the conductive slurry. Under a 50x television microscope, the stainless steel thin rod was used as a reference for the resistance wire debugging length. The spot coating length required for the resistance wire precision debugging was controlled under the television microscope.

[0014] Furthermore, the conductive paste is conductive silver paste.

[0015] Furthermore, during the process of sintering and curing the conductive paste to form a stable short-circuit debugging point, the sintering temperature is controlled to be 670±10° C. and the heat preservation time is greater than 5 minutes.

[0016] Furthermore, the method of performing accuracy testing on the temperature sensing component in a 0°C environment includes:

[0017] Place the temperature sensing component after the conductive paste is sintered in a constant temperature alcohol bath at 0°C, and test the resistance value of the temperature sensing end of the temperature sensing component at 0°C to determine whether the resistance of the temperature sensing end resistance wire at 0°C meets the resistance value requirement of the corresponding graduation value.

[0018] Furthermore, the resistance wire is a platinum wire, and the corresponding graduation values ​​include PT100 and PT1000.

[0019] Furthermore, after the two resistance wires are wound around the frame as temperature sensing components and before the conductive slurry is applied, a sealing glass sleeve is used to seal the frame wound with the resistance wires, and the ends of the two resistance wires away from the leads are exposed outside the sealing glass.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention adopts a process method of short-circuiting the resistance wire with a conductive paste to reduce the output size of the resistance value in the loop. Compared with the original process method of gradually trimming the length of the resistance wire and then forming a debugging node by welding, the controllability of the resistance value of the temperature sensing component and the operability of the debugging during the debugging process are greatly enhanced; especially in the case of debugging ultra-fine resistance wires, the debugging pass rate and debugging efficiency can also be greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flow chart of the precision debugging method of the temperature sensing component based on the ultra-fine resistance wire in Example 1 or 2;

[0022] Figure 2 This is a schematic diagram of the short-circuit debugging point structure of the temperature sensing component of the ultra-fine resistance wire in Example 1 or 2;

[0023] Among them, 1. resistance wire; 2. lead wire; 3. frame; 4. short-circuit debugging point; 5. sealing glass. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below in conjunction with the embodiments and drawings. However, it should not be understood that the scope of the above subject matter of the present invention is limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0025] Example 1

[0026] See also Figure 1 and Figure 2 , a method for adjusting the accuracy of a temperature sensing component based on an ultra-fine resistance wire, comprising:

[0027] The two strands of resistance wire 1 are electrically connected to the lead wire 2 respectively, and the two strands of resistance wire 1 are wound around the frame 3 as temperature sensing components;

[0028] Apply the conductive slurry between the two resistance wires 1, place the temperature sensing component after the conductive slurry is applied in a high-temperature furnace, and sinter and solidify the conductive slurry to form a stable short-circuit debugging point 4 according to the sintering temperature characteristics of the conductive slurry;

[0029] After the conductive paste is sintered, the temperature sensing component is tested for accuracy in a 0°C environment. If the resistance of the temperature sensing end resistor wire 1 at 0 degrees Celsius meets the resistance value requirement of the corresponding graduation value, the debugging is completed; otherwise, the dot coating position is changed, and the conductive paste is sintered and solidified to form a new short-circuit debugging point 4 until the resistance of the temperature sensing end resistor wire 1 at 0 degrees Celsius meets the resistance value requirement of the corresponding graduation value.

[0030] In this embodiment, the process method of using conductive paste to short-circuit the resistor wire 1 to reduce the output resistance value in the loop is compared with the original process method of gradually trimming the length of the resistor wire 1 and then forming a debugging node by welding. The controllability of the resistance value of the temperature sensing component and the operability of the debugging during the debugging process are greatly enhanced; especially in the case of debugging ultra-fine resistor wire 1, the debugging pass rate and debugging efficiency can also be greatly improved.

[0031] Example 2

[0032] See also Figure 1 and Figure 2This embodiment takes a 0.02mm Ф platinum wire as an example to explain in detail the process of the precision debugging method of the temperature sensing component based on the ultra-fine resistance wire of the present invention. In this embodiment, the precision adjustable range of the 0.02mm Ф platinum wire is only about 0.3Ω / mm. According to the PT100 A-level precision conversion, the adjustable length is about 0.2mm. The specific debugging steps are as follows:

[0033] Step 1: electrically connect the two resistance wires 1 to the lead wires 2 respectively, and wind the two resistance wires 1 around the frame 3 as temperature sensing components;

[0034] In this embodiment, the two platinum wires can be formed by folding one platinum wire in half, or by merging two platinum wires. During the winding process, it is necessary to ensure that there is no contact between the two platinum wires. The skeleton 3 in this embodiment is made of ceramic material, and other high temperature resistant and non-conductive materials are also applicable to the present invention.

[0035] Step 2: Use sealing glass 5 to cover the frame 3 wrapped with the resistance wire 1 for sealing, and make the ends of the two resistance wires 1 away from the lead wire 2 exposed outside the sealing glass 5;

[0036] In this embodiment, the portion exposed from the sealing glass 5 is used for spot coating of the conductive paste to ensure that the portion covered by the sealing glass 5 can be stable and undisturbed, which is conducive to achieving precision adjustment of the resistance wire 1.

[0037] Step 3: Apply the conductive slurry between the two resistance wires 1, place the temperature sensing component after the conductive slurry is applied in a high-temperature furnace, and sinter and solidify the conductive slurry to form a stable short-circuit debugging point 4 according to the sintering temperature characteristics of the conductive slurry;

[0038] In this embodiment, since the object to be debugged is a resistance wire 1 with a wire diameter of only 0.02mm, the adjustable range of precision is only about 0.3Ω / mm. According to the PT100 graduation A-level precision conversion, the adjustable length is about 0.2mm; since the resistance wire 1 is ultra-thin and the adjustable length is extremely small, in order to enhance operability, the temperature sensing component is placed under a 50x TV microscope for operation. During the spot coating process, a stainless steel thin rod with a diameter of 0.5mm is selected as a tool for spot coating the conductive paste. The size of 0.5mm can be used as a reference for the debugging length of the resistance wire 1 under a 50x TV microscope in the subsequent debugging process, which is convenient for controlling the debugging length of the resistance wire 1 under the microscope.

[0039] In this embodiment, conductive silver paste is taken as an example. According to the sintering temperature characteristics of the conductive silver paste, 670° C. is selected as the sintering point, and the holding time is 10 minutes, so as to sinter and solidify the conductive paste to form a stable short-circuit debugging point 4.

[0040] Step 4: After the conductive paste is sintered, the temperature sensing component is tested for accuracy in a 0°C environment. If the resistance of the temperature sensing end resistor wire 1 at 0°C meets the resistance value requirement of the corresponding scale value, the debugging is completed; otherwise, the dot coating position is changed, and the conductive paste is sintered and solidified to form a new short-circuit debugging point 4, until the resistance of the temperature sensing end resistor wire 1 at 0°C meets the resistance value requirement of the corresponding scale value;

[0041] In this embodiment, the temperature sensing component after the conductive paste is sintered is placed in a constant temperature alcohol tank at 0°C, and the resistance value of the temperature sensing end of the temperature sensing component at 0°C is tested to determine whether the resistance of the temperature sensing end resistance wire 1 at 0°C meets the resistance value requirement of the corresponding graduation value. According to the PT100 graduation conversion, the resistance at 0°C should meet 100±0.5Ω, and the debugging is completed.

[0042] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for adjusting the accuracy of a temperature sensing component based on ultra-fine resistance wire, characterized in that: include: The two strands of resistance wire (1) are electrically connected to the lead wire (2) respectively, and the two strands of resistance wire (1) are wound around the frame (3) as temperature sensing components; Applying a conductive slurry between two resistance wires (1), placing the temperature sensing component after the conductive slurry is applied in a high-temperature furnace, and sintering and curing the conductive slurry to form a stable short-circuit debugging point (4) according to the sintering temperature characteristics of the conductive slurry; After the conductive paste is sintered, the temperature sensing component is tested for accuracy in a 0°C environment. If the resistance of the temperature sensing end resistor wire (1) at 0°C meets the resistance value requirement of the corresponding graduation value, the debugging is completed. Otherwise, the dot coating position is changed, and the conductive paste is sintered and solidified to form a new short-circuit debugging point (4), until the resistance of the temperature sensing end resistance wire (1) at 0 degrees Celsius meets the resistance value requirement of the corresponding graduation value.

2. The method for adjusting the precision of a temperature sensing component based on ultra-fine resistance wire according to claim 1 is characterized in that: The skeleton (3) is made of ceramic material.

3. The method for adjusting the precision of a temperature sensing component based on ultra-fine resistance wire according to claim 1 is characterized in that: The method of applying a conductive slurry between two resistance wires (1) comprises: A stainless steel thin rod with a diameter of 0.5 mm is selected as a tool for spot coating of the conductive paste. Under a 50x television microscope, the stainless steel thin rod is used as a reference for adjusting the length of the resistance wire (1). The spot coating length required for the precision adjustment of the resistance wire (1) is controlled under the television microscope.

4. The method for adjusting the precision of a temperature sensing component based on ultra-fine resistance wire according to claim 1, characterized in that: The conductive paste is conductive silver paste.

5. The method for adjusting the precision of a temperature sensing component based on ultra-fine resistance wire according to claim 4 is characterized in that: During the process of sintering and curing the conductive paste to form a stable short-circuit debugging point (4), the sintering temperature is controlled to be 670±10° C. and the heat preservation time is greater than 5 minutes.

6. The method for adjusting the precision of a temperature sensing component based on ultra-fine resistance wire according to claim 1, characterized in that: Methods for testing the accuracy of temperature sensing components in a 0°C environment include: The temperature sensing component after sintering the conductive paste is placed in a constant temperature alcohol bath at 0°C, and the resistance value of the temperature sensing end of the temperature sensing component at 0°C is tested to determine whether the resistance of the temperature sensing end resistance wire (1) at 0°C meets the resistance value requirement of the corresponding graduation value.

7. The method for adjusting the precision of a temperature sensing component based on ultra-fine resistance wire according to claim 1, characterized in that: The resistance wire (1) is a platinum wire, and the corresponding graduation values ​​include PT100 and PT1000.

8. The method for adjusting the precision of a temperature sensing component based on ultra-fine resistance wire according to claim 1, characterized in that: After two strands of resistance wire (1) are wound around a frame (3) as a temperature sensing component and before the conductive slurry is applied, a sealing glass (5) is used to cover the frame (3) wound with the resistance wire (1) for sealing, and the end portions of the two strands of resistance wire (1) away from the lead wire (2) are exposed outside the sealing glass (5).

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