A wire tension measurement sensor and method of manufacture

Abstract

The application relates to the technical field of wire tension measurement, and discloses a wire tension measurement sensor and a manufacturing method, which comprise an elastic body; a mounting hole is arranged at the center of the elastic body; four symmetrical single-axis silicon piezoresistance MEMS chips are arranged on the upper surface of the elastic body along the length direction of the elastic body, and the four single-axis silicon piezoresistance MEMS chips are located on the two sides of the mounting hole in pairs to form a Wheatstone bridge; each single-axis silicon piezoresistance MEMS chip is connected with the elastic body through a glass layer; when in use, the wire tension measurement sensor is provided with the single-axis silicon piezoresistance MEMS chips on the surface of the elastic body, and the single-axis silicon piezoresistance MEMS chips are connected with the elastic body through the glass layer, so that the organic material aging problem can be avoided on one hand, and the service life is long; on the other hand, the single-axis piezoresistance type MEMS force sensitive chip can reduce the non-sensitive axis cross interference, improve the measurement precision, and the detection speed is fast.

Description

Technical Field

[0001] This invention relates to the field of line tension measurement technology, specifically to a line tension measurement sensor and its manufacturing method. Background Technology

[0002] In the textile weaving industry, the tension control of warp and weft yarns is one of the key factors affecting fabric quality and production efficiency. Excessive tension can easily lead to yarn breakage, causing downtime and material waste; insufficient tension will result in loose fabrics and uneven density, affecting product quality. Especially in high-speed looms (speed > 1000 rpm), high-precision real-time measurement of yarn tension is a prerequisite for achieving closed-loop control. Furthermore, as textile machinery develops towards higher speeds and greater intelligence, higher requirements are placed on tension measurement sensors: high precision, fast response, small size, low cost, and strong environmental adaptability.

[0003] In addition, existing tension measurements are mainly achieved through the following two methods:

[0004] Method 1: Manual experience method. Operators adjust the tension device based on their experience. This method relies entirely on the operator's experience, without real-time measurement data support, and cannot achieve quantitative control, resulting in poor product consistency and high scrap rate. Method 2: Measurement using a mechanical tensioner, which provides constant resistance through a spring and friction plate structure. However, this method has the following drawbacks: it cannot measure tension values ​​in real time, it cannot achieve closed-loop feedback control, tension drift is caused by mechanical wear, and it cannot adapt to rapid switching between different yarn specifications. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the present invention provides a line tension measuring sensor that can measure in real time and with high precision, and a method for manufacturing it.

[0006] To solve the above technical problems, in a first aspect, the present invention provides the following technical solution: a line tension measuring sensor, comprising an elastic body; The elastomer has a mounting hole at its center; Four symmetrical uniaxial silicon piezoresistive MEMS chips are arranged along the length of the elastic body on the upper surface of the elastic body, and the four uniaxial silicon piezoresistive MEMS chips are located in pairs on both sides of the mounting hole to form a Wheatstone bridge. Each uniaxial silicon piezoresistive MEMS chip is connected to an elastomer via a glass layer.

[0007] In one embodiment of the first aspect, signal transmission wires are respectively provided on both sides of the mounting hole on the upper surface of the elastomer between the two MEMS chips.

[0008] In one embodiment of the first aspect, the material of the elastomer is 17-4PH stainless steel, the length, width and height of the elastomer are 80mm, 5mm and 0.7mm respectively, and the shear strength of the uniaxial silicon piezoresistive MEMS chip after being connected to the elastomer is ≥50Mpa.

[0009] In one embodiment of the first aspect, the present invention further includes a fixing box, the fixing box including a box body and a box cover located on the top surface of the box body, the upper surface of the box body is provided with a first recess, and the bottom surface of the first recess is provided with a second recess facing downward; The bottom surface of the first recess has first fixing holes on the left and right sides of the second recess, and the two ends of the elastic body are respectively installed in the first fixing holes; The bottom surface of the first recess has second fixing holes on the left and right sides of the second recess, respectively. The second fixing holes are below the first fixing holes, and circuit boards are fixed in the two second fixing holes. The circuit board includes a signal processing circuit, an MCU control circuit, a voltage regulator circuit, a serial port circuit, and a communication interface. The communication interface includes two communication terminals, a power supply terminal, and a ground terminal. The two communication terminals are electrically connected to the serial port circuit. The power supply terminal provides the power supply voltage, and the ground terminal is used for grounding. The voltage regulator circuit is electrically connected to the power supply terminal of the communication interface, and the power supply voltage of the communication interface provides the operating voltage for the signal processing circuit, the MCU control circuit and the serial port circuit. The signal processing circuit is used to convert the analog signal output by the Wheatstone bridge into a digital signal. The MCU control circuit processes the digital signal to obtain the line tension detection value, and outputs it through the serial port circuit. The second recessed bottom surface is provided with a shock-absorbing block integrally formed with the upper wall of the second recessed surface. The shock-absorbing block is provided with a slidable pull rod. The pull rod passes through the box body and has a through hole at one end located outside the box body. The bottom surface of the pull rod has an inward groove. A pull rod is installed in the groove. The pull rod passes through the mounting hole and the end passing through the mounting hole abuts against the lower surface of the elastic body.

[0010] In one embodiment of the first aspect, the bottom surface of the second recess is provided with two upper limit blocks above the elastic body, and the two upper limit blocks are on both sides of the pull rod; the bottom surface of the second recess is provided with a lower limit block corresponding to the upper limit blocks below the elastic body.

[0011] In one embodiment of the first aspect, a communication groove is provided on the lower wall of the housing, and the communication interface is located in the communication groove; The upper and lower outer walls of the box are respectively equipped with fixing seats, and the fixing seats are provided with a third fixing hole.

[0012] In one embodiment of the first aspect, the MCU control circuit performs temperature compensation on the digital signal and outputs a line tension detection value. The temperature compensation model is as follows: F_compensated = F_raw × S(T) + Z(T). Among them: S(T)=1+α•ΔT+β•ΔT²; Z(T)=γ•ΔT+δ•ΔT²; ΔT=T_current-T_reference; α and β are the sensitivity temperature coefficients; γ and δ are the zero-point temperature coefficients; T_reference is the reference temperature; T_current is the current temperature; F_raw is the digital signal output by the signal processing circuit; F_compensated is the line tension detection value.

[0013] In one embodiment of the first aspect, the process of generating the temperature compensation model is as follows: S1: Place the sensor in the temperature control box; S2: Set the calibration temperature, with a duration of more than 30 minutes; S3: Apply loads to the sensor sequentially and record the sensor's raw output data; the loads include 0, 25g, 50g, 75g, 100g, 125g, 150g, 175g, 200g, and 250g; S4: Change the calibrated temperature in step S2 until the number of times step S2 is executed reaches the preset number; S5: Based on all the original output data obtained, the coefficients of α, β, γ, and δ are fitted using the least squares method.

[0014] Secondly, the present invention provides a method for manufacturing a line tension measuring sensor, which includes the following steps: S1: First, apply glass slurry to four symmetrically arranged preset areas on the upper surface of the elastomer made of 17-4PH stainless steel, and then dry the glass slurry to remove the organic carrier; the elastomer has a mounting hole in the center, and the four preset areas are located on both sides of the mounting hole. S2: Next, a uniaxial silicon piezoresistive MEMS chip is attached to each glass paste. S3: Sintering of uniaxial silicon piezoresistive MEMS chips in a chain sintering furnace, wherein the heating rate is between 5 and 10℃ / min; the holding temperature is between 450℃ and 500℃; the holding time is between 20 and 40 min; nitrogen or argon gas is used for protection; slow cooling rate: ≤3℃ / min; S4: Assemble the elastomer with the box body, wherein a first recess is provided on the upper surface of the box body, and a second recess is provided with the bottom surface of the first recess facing downwards; The bottom surface of the first recess has first fixing holes on the left and right sides of the second recess, respectively. During assembly, the two ends of the elastomer are respectively installed in the first fixing holes. The bottom surface of the first recess has second fixing holes on the left and right sides of the second recess, respectively. The second fixing holes are below the first fixing holes, and circuit boards are fixed in the two second fixing holes. The circuit board includes a signal processing circuit, an MCU control circuit, a voltage regulator circuit, a serial port circuit, and a communication interface. The communication interface includes two communication terminals, a power supply terminal, and a ground terminal. The two communication terminals are electrically connected to the serial port circuit. The power supply terminal provides the power supply voltage, and the ground terminal is used for grounding. The voltage regulator circuit is electrically connected to the power supply terminal of the communication interface, and the power supply voltage of the communication interface provides the operating voltage for the signal processing circuit, the MCU control circuit and the serial port circuit. The signal processing circuit is used to convert the analog signal output by the Wheatstone bridge into a digital signal. The MCU control circuit processes the digital signal to obtain the line tension detection value, and outputs it through the serial port circuit. The bottom surface of the second recess is provided with a shock-absorbing block integrally formed with the upper wall surface of the second recess; the shock-absorbing block is provided with a slidable pull rod, the pull rod passes through the box body and has a through hole at one end located outside the box body, and the bottom surface of the pull rod has an inward groove. The pull rod is passed through the mounting hole, with one end threaded into the groove, while the other end of the pull rod abuts against the lower surface of the elastomer. S5: Install a lid on the top surface of the box to form a fixed box.

[0015] In one embodiment of the second aspect, before performing step S1, the elastomer is first laser-cleaned to remove surface oil and oxide layers, and then the surface of the elastomer is activated to increase surface energy and increase the adhesion of glass slurry; finally, positioning marks are set on the surface of the elastomer, which are used to locate the attachment position of the uniaxial silicon piezoresistive MEMS chip.

[0016] The advantages of this invention compared to the prior art are as follows: The linear tension measurement sensor of this invention, by setting a uniaxial silicon piezoresistive MEMS chip on the surface of the elastomer and connecting the uniaxial silicon piezoresistive MEMS chip to the elastomer through a glass layer, can avoid the aging problem of organic materials and have a long service life. On the other hand, the uniaxial piezoresistive MEMS force-sensitive chip can reduce the cross-interference of non-sensitive axes, improve the measurement accuracy and detection speed. Attached Figure Description

[0017] Figure 1This is a schematic diagram showing the distribution of the uniaxial silicon piezoresistive MEMS chip on the upper surface of the elastomer in Example 1. Figure 2 This is a schematic diagram of the structure of the fixing box in the embodiment; Figure 3 for Figure 2 A schematic diagram of the structure after removing the box lid; Figure 4 This is a schematic diagram of the circuit structure on the circuit board; Figure 5 This is the circuit diagram for the MCU control circuit. Figure 6 This is a circuit diagram of the communication interface in the embodiment; Figure 7 This is a circuit diagram of the voltage regulator circuit in the embodiment; Figure 8 This is a circuit diagram of the signal processing circuit in the embodiment; Figure 9 This is a circuit diagram of the serial port circuit in the embodiment. Detailed Implementation

[0018] The illustrative embodiments of this application include, but are not limited to, a line tension measuring sensor and a method for manufacturing it.

[0019] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0020] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items. Words such as “comprising” or “including” mean that the element or object preceding “comprising” or “including” covers the element or object listed following “comprising” or “including” and its equivalents, and does not exclude other elements or objects. Words such as “connected” or “linked” are not limited to physical or mechanical connections and can include electrical connections, whether direct or indirect.

[0021] Example 1 like Figure 1As shown, this embodiment provides a line tension measuring sensor, including an elastic body 10; The elastomer 10 has a mounting hole 11 at its center; Four symmetrical uniaxial silicon piezoresistive MEMS chips 12 are provided on the upper surface of the elastomer 10 along the length of the elastomer, and the four uniaxial silicon piezoresistive MEMS chips 12 are located on both sides of the mounting hole 11 in pairs to form a Wheatstone bridge. Each uniaxial silicon piezoresistive MEMS chip 12 is connected to an elastomer via a glass layer.

[0022] The actual measurement process of the structure shown in Figure 1 of the present invention is as follows: The two ends of the elastomer 10 are fixed, and then the line tension transmission part is installed in the mounting hole 11. Under the action of line tension, the line tension transmission part causes the elastomer 10 to deform, thereby causing the uniaxial silicon piezoresistive MEMS chip 12 to output electrical signals of different magnitudes.

[0023] In practical use, the linear tension measurement sensor of the present invention, by setting a uniaxial silicon piezoresistive MEMS chip 12 on the surface of the elastomer 10 and connecting the uniaxial silicon piezoresistive MEMS chip 12 to the elastomer through a glass layer, can avoid the aging problem of organic materials and have a long service life. On the other hand, the uniaxial piezoresistive MEMS force-sensitive chip can reduce the cross-interference of non-sensitive axes, improve the measurement accuracy and the detection speed.

[0024] Specifically, in this embodiment, the material of the elastomer 10 is 17-4PH stainless steel, which can ensure good elastic deformation characteristics and guarantee overload capacity and fatigue resistance; in addition, the shear strength of the uniaxial silicon piezoresistive MEMS chip 12 after being connected to the elastomer is ≥50Mpa. The uniaxial silicon piezoresistive MEMS chip 12 is connected to the elastomer 10 through the glass layer, which can also reduce thermal stress.

[0025] Specifically, in this embodiment, the length, width and height of the elastomer 10 are 80mm, 5mm and 0.7mm respectively. This size, plus the mounting hole, can make the elastomer 10 generate a symmetrical strain concentration area, which is convenient for chip placement, has strong resistance to eccentric loads, separates bending moment and shear force, and improves measurement accuracy.

[0026] In addition, the strain beam thickness of 0.7mm was determined based on the strain requirement (approximately 500με) at full scale of 0.1N, combined with the elastic modulus of 17-4PH, and the calculation formula is: ε=(6×F×L) / (E×b×h²). Where: ε is the strain value, F is the load (0.1N), L is the lever arm length, E is the elastic modulus (196GPa), b is the beam width, and h is the beam thickness (0.7mm).

[0027] Specifically, in this embodiment, in Figure 1 In the middle, on the upper surface of the elastomer 10, on both sides of the mounting hole 11, signal transmission wires 13 are respectively provided between the two MEMS chips 12.

[0028] Furthermore, in this embodiment, the present invention also includes a fixing box 2, the structure of which is as follows: Figure 2 and 3 As shown, it includes a box body 20 and a box lid 21 located on the top surface of the box body 20. Figure 3 In the middle, a first recess 22 is provided on the upper surface of the box body 20, and a second recess 23 is provided on the bottom surface of the first recess 22. The bottom surface of the first recess 22 is provided with first fixing holes 220 on the left and right sides of the second recess 23 respectively. The two ends of the elastic body 10 are respectively installed in the first fixing holes 220. In practical application, by setting two first fixing holes 220 to fix the two ends of the elastic body 10, the two ends of the elastic body 10 can be isolated from the application concentration area, which can reduce the influence of installation stress on measurement. The bottom surface of the first recess 22 is provided with second fixing holes 221 on the left and right sides of the second recess 23 respectively. The second fixing holes 221 are below the first fixing hole 220, and circuit boards 29 are fixed in the two second fixing holes 221. Reference Figure 4 The circuit board 29 includes a signal processing circuit 290, an MCU control circuit 291, a voltage regulator circuit 294, a serial port circuit 292, and a communication interface 293; the circuit of the communication interface 293 is as follows: Figure 6 As shown, it includes two communication terminals (pins 1 and 2 of J1), one power supply terminal (pin 3 of J1), and one ground terminal (pin 4 of J1); the two communication terminals are electrically connected to the serial port circuit 292; the power supply terminal is used to provide the power supply voltage, which is 5V DC voltage; the ground terminal is used for grounding. The voltage regulator circuit 294 is electrically connected to the power supply terminal of the communication interface 294. The power supply voltage of the communication interface 294 provides the operating voltage for the signal processing circuit 290, the MCU control circuit 291, and the serial port circuit 292. The signal processing circuit 290 is used to convert the analog signal output by the Wheatstone bridge into a digital signal. The MCU control circuit 291 processes the digital signal to obtain the line tension detection value and outputs it through the serial port circuit 292. Furthermore, the circuit of the MCU control circuit 291 is as follows: Figure 5 As shown, it includes an MCU of model HK32G003F4P7, and U2 is a programming interface used to program the MCU; the circuit of voltage regulator circuit 294 is as follows. Figure 7 As shown, it is used to convert 5V DC voltage to 3.3V DC voltage; the circuit of signal processing circuit 290 is as follows. Figure 8As shown, the analog signal output from the Wheatstone bridge is amplified, actively filtered, and converted from analog to digital by chip U4; the circuit of serial port circuit 292 is as follows. Figure 9 As shown; Additionally, a shock-absorbing block 24 is integrally formed with the upper wall of the second recess 23 on the bottom surface of the second recess 23. A slidable pull rod 25 is provided in the shock-absorbing block 24. The pull rod 25 passes through the box 20 and has a through hole 250 at one end outside the box 20. A groove is formed inward on the bottom surface of the pull rod 25. A pull rod 26 is installed in the groove. The pull rod 26 passes through the mounting hole 11 and the end passing through the mounting hole 11 abuts against the lower surface of the elastic body 10. Thus, when the wire passes through the through hole 250 and drives the pull rod 25 in a direction away from the elastic body 10, the pull rod 26 will pull the elastic body 10, thereby causing deformation in the strain concentration area of ​​the elastic body 10, and realizing the measurement of line tension.

[0029] Specifically, in this embodiment, in Figure 3 In the middle, the bottom surface of the second recess 23 is provided with two upper limit blocks 270 above the elastic body 10, and the two upper limit blocks 270 are on both sides of the pull rod 26; the bottom surface of the second recess 23 is provided with a lower limit block 271 corresponding to the upper limit block 2670 below the elastic body 10.

[0030] In practical use, the strain range of the elastic body 10 can be limited by the upper limit block 2670 and the lower limit block 271 to prevent excessive deformation of the elastic body 10.

[0031] Specifically, in this embodiment, in Figure 3 In the middle, a communication groove 200 is provided on the lower wall of the box 20, and the communication interface 294 is located in the communication groove 200; thus realizing signal interaction with the external terminal; Fixing bases 28 are installed on the upper and lower outer walls of the housing 20, and the fixing bases 28 have a third fixing hole 280. In actual installation, the measuring sensor can be fixed at the position to be measured by passing screws through the third fixing hole 280.

[0032] In actual line tension measurement, the temperature drift of the uniaxial silicon piezoresistive MEMS chip 12, the zero-point temperature drift, the additional strain caused by the difference in thermal expansion coefficients between the uniaxial silicon piezoresistive MEMS chip 12 and the elastomer 10, the release of residual stress from the package with temperature, the temperature drift of circuit components, and the effect of temperature on the deformation of the elastomer 10 will all affect the accuracy of the detection results. In order to perform the detection more accurately, in this embodiment, the MCU control circuit 291 performs temperature compensation on the digital signal and outputs the line tension detection value. The temperature compensation model is as follows: F_compensated=F_raw×S(T)+Z(T); Among them: S(T)=1+α•ΔT+β•ΔT²; Z(T)=γ•ΔT+δ•ΔT²; ΔT=T_current-T_reference; α and β are the sensitivity temperature coefficients; γ and δ are the zero-point temperature coefficients; T_reference is the reference temperature; T_current is the current temperature; F_raw is the digital signal output by the signal processing circuit; F_compensated is the line tension detection value.

[0033] Furthermore, in this embodiment, the generation process of the temperature compensation model is as follows: S1: Place the sensor in the temperature control box; S2: Set the calibration temperature, with a duration of more than 30 minutes; S3: Apply loads to the sensor sequentially and record the sensor's raw output data; the loads include 0, 25g, 50g, 75g, 100g, 125g, 150g, 175g, 200g, and 250g. S4: Change the calibration temperature in step S2 until the number of times step S2 is executed reaches the preset number; where the calibration temperature is set to five values: -20℃, 0℃, 25℃, 50℃, and 70℃, the preset number of times in step S4 is 5. S5: Based on all the original output data obtained, the coefficients of α, β, γ, and δ are fitted using the least squares method.

[0034] After temperature compensation, the measurement accuracy of the sensor remains within ±0.5% across the entire temperature range of -20℃ to 70℃.

[0035] In summary, the measurement sensor in this embodiment has the following beneficial effects: First, it achieves high-precision measurement with an accuracy of 0.01%FS, capable of distinguishing tension changes as small as 0.01g, meeting the stringent requirements for tension control in high-quality fabrics. Second: By implementing temperature compensation, the accuracy can be maintained within ±0.5% in a temperature range of -20℃ to 70℃, adapting to various textile workshop environments; Third: High-reliability glass micro-fusion encapsulation has no organic material aging problem, good fatigue resistance, and a design life of >10 years, which is far higher than the 3-5 year life of organic glue encapsulation; Fourth: It can respond quickly, with a response time of milliseconds (<5ms), meeting the real-time closed-loop control requirements of high-speed looms with rotation speeds >1000rpm; 5. The sensor is small and lightweight. Its compact size (80×5×0.7mm) and light weight (<50g) make it easy to install in the confined space of a loom.

[0036] Example 2 This embodiment provides a method for manufacturing a line tension measuring sensor, which includes the following steps: S1: First, apply glass slurry to four symmetrically arranged preset areas on the upper surface of the elastomer 10 made of 17-4PH stainless steel, and then dry the glass slurry to remove the organic carrier; the center of the elastomer 10 has an installation hole 11, and the four preset areas are located on both sides of the installation hole 11. Specifically, in step S1, the glass paste is a lead-free glass paste with a softening point of 475℃; the drying temperature is 150℃ and the drying time is 30 minutes. S2: Next, a uniaxial silicon piezoresistive MEMS chip 12 is attached to each glass paste. S3: Sinter the uniaxial silicon piezoresistive MEMS chip 12 in a chain sintering furnace, wherein the heating rate is between 5 and 10℃ / min; the holding temperature is between 450℃ and 500℃; the holding time is between 20 and 40 min; nitrogen or argon gas is used for protection; slow cooling rate: ≤3℃ / min; S4: Assemble the elastomer 10 with the box 20. The upper surface of the box 20 is provided with a first recess 200, and the bottom surface of the first recess 22 is provided with a second recess 23. The bottom surface of the first recess 22 is provided with first fixing holes 220 on the left and right sides of the second recess 23 respectively. During assembly, the two ends of the elastomer 10 are respectively installed in the first fixing holes 220. The bottom surface of the first recess 22 is provided with second fixing holes 221 on the left and right sides of the second recess 23 respectively. The second fixing holes 221 are below the first fixing hole 220, and circuit boards 29 are fixed in the two second fixing holes 221. The circuit board 29 includes a signal processing circuit 290, an MCU control circuit 291, a voltage regulator circuit 294, a serial port circuit 292, and a communication interface 293; the circuit of the communication interface 293 is as follows: Figure 6 As shown, it includes two communication terminals (pins 1 and 2 of J1), one power supply terminal (pin 3 of J1), and one ground terminal (pin 4 of J1); the two communication terminals are electrically connected to the serial port circuit 292; the power supply terminal is used to provide the power supply voltage, which is 5V DC voltage; the ground terminal is used for grounding. The voltage regulator circuit 294 is electrically connected to the power supply terminal of the communication interface 294. The power supply voltage of the communication interface 294 provides the operating voltage for the signal processing circuit 290, the MCU control circuit 291, and the serial port circuit 292. The signal processing circuit 290 is used to convert the analog signal output by the Wheatstone bridge into a digital signal. The MCU control circuit 291 processes the digital signal to obtain the line tension detection value and outputs it through the serial port circuit 292. The bottom surface of the second recess 23 is provided with a shock-absorbing block 24 integrally formed with the upper wall surface of the second recess 23; the shock-absorbing block 24 is provided with a sliding pull rod 25, the pull rod 25 passes through the box 20 and has a through hole 250 at one end outside the box 20, and the bottom surface of the pull rod 25 has an inward groove. The pull rod 26 is passed through the mounting hole 11, and one end of the pull rod 26 is threaded into the groove, while the other end of the pull rod 11 abuts against the lower surface of the elastomer 10. S5: Install the cover 21 on the top surface of the box body 20 to form a fixed box 2.

[0037] Specifically, in this embodiment, before performing step S1, the elastomer 10 is first laser-cleaned to remove surface oil and oxide layer, and then the surface of the elastomer 10 is activated to improve surface energy and increase the adhesion of glass paste; finally, positioning marks are set on the surface of the elastomer 10, which are used to locate the attachment position of the uniaxial silicon piezoresistive MEMS chip 12.

[0038] Based on the above description, those skilled in the art can make various changes and modifications without departing from the technical concept of this invention. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A line tension measuring sensor, characterized in that, Including elastomers (10); The elastomer (10) has a mounting hole (11) at its center; Four symmetrical uniaxial silicon piezoresistive MEMS chips (12) are provided on the upper surface of the elastic body (10) along the length direction of the elastic body (10), and the four uniaxial silicon piezoresistive MEMS chips (12) are located on both sides of the mounting hole (11) to form a Wheatstone bridge. Each uniaxial silicon piezoresistive MEMS chip (12) is connected to the elastomer (10) through a glass layer.

2. The line tension measuring sensor according to claim 1, characterized in that, On the upper surface of the elastomer (10), on both sides of the mounting hole (11), signal transmission wires (13) are respectively provided between the two MEMS chips (12).

3. A line tension measuring sensor according to claim 1, characterized in that, The material of the elastomer (10) is 17-4PH stainless steel. The length, width and height of the elastomer (10) are 80mm, 5mm and 0.7mm respectively. The shear strength of the uniaxial silicon piezoresistive MEMS chip (12) after being connected to the elastomer (10) is ≥50Mpa.

4. A line tension measuring sensor according to any one of claims 1-3, characterized in that, It also includes a fixing box (2), which includes a box body (20) and a box cover (21) located on the top surface of the box body (20). A first recess (22) is provided on the upper surface of the box body (20), and a second recess (23) is provided on the bottom surface of the first recess (22). The bottom surface of the first recess (22) is provided with first fixing holes (220) on the left and right sides of the second recess (23), and the two ends of the elastic body (10) are respectively installed in the first fixing holes (220); The bottom surface of the first recess (22) is provided with second fixing holes (221) on the left and right sides of the second recess (23), respectively. The second fixing holes (221) are below the first fixing hole (220), and circuit boards (29) are fixed in the two second fixing holes (221). The circuit board (29) is provided with a signal processing circuit (290), an MCU control circuit (291), a voltage regulator circuit (294), a serial port circuit (292), and a communication interface (293); the communication interface (293) includes two communication terminals, a power supply terminal, and a ground terminal; the two communication terminals are electrically connected to the serial port circuit (292); the power supply terminal is used to provide power supply voltage; the ground terminal is used for grounding; The voltage regulator circuit (294) is electrically connected to the power supply terminal of the communication interface (293). The power supply voltage of the power supply terminal of the communication interface provides the operating voltage for the signal processing circuit (290), the MCU control circuit (291), and the serial port circuit (292). The signal processing circuit (290) is used to convert the analog signal output by the Wheatstone bridge into a digital signal. The MCU control circuit (291) processes the digital signal to obtain the line tension detection value and outputs it through the serial port circuit (292). The bottom surface of the second recess (23) is provided with a shock-absorbing block (24) integrally formed with the upper wall of the second recess (23). The shock-absorbing block (24) is provided with a sliding pull rod (25). The pull rod (25) passes through the box body (20) and has a through hole (250) at one end outside the box body (20). The bottom surface of the pull rod (25) is provided with a groove. A pull rod (26) is installed in the groove. The pull rod (26) passes through the mounting hole (11) and the end passing through the mounting hole (11) abuts against the lower surface of the elastic body (10).

5. A line tension measuring sensor according to claim 4, characterized in that, The bottom surface of the second recess (23) is provided with two upper limit blocks (270) above the elastic body (10), and the two upper limit blocks (270) are on both sides of the pull rod (26); the bottom surface of the second recess (23) is provided with a lower limit block (271) corresponding to the upper limit block (270) below the elastic body (10).

6. A line tension measuring sensor according to claim 4, characterized in that, A communication groove (200) is provided on the lower wall surface of the box (20), and the communication interface (293) is located in the communication groove (200); The upper and lower outer walls of the box (20) are respectively equipped with fixing seats (28), and the fixing seats (28) are provided with a third fixing hole (280).

7. A line tension measuring sensor according to claim 4, characterized in that, The MCU control circuit (291) performs temperature compensation on the digital signal and outputs the line tension detection value. The temperature compensation model is as follows: F_compensated=F_raw×S(T)+Z(T); Among them: S(T)=1+α•ΔT+β•ΔT²; Z(T)=γ•ΔT+δ•ΔT²; ΔT=T_current-T_reference; α and β are the sensitivity temperature coefficients; γ and δ are the zero-point temperature coefficients; T_reference is the reference temperature; T_current is the current temperature; F_raw is the digital signal output by the signal processing circuit; F_compensated is the line tension detection value.

8. A line tension measuring sensor according to claim 7, characterized in that, The generation process of the temperature compensation model is as follows: S1: Place the sensor in the temperature control box; S2: Set the calibration temperature, with a duration of more than 30 minutes; S3: Apply loads to the sensor sequentially and record the sensor's raw output data; the loads include 0, 25g, 50g, 75g, 100g, 125g, 150g, 175g, 200g, and 250g; S4: Change the calibrated temperature in step S2 until the number of times step S2 is executed reaches the preset number; S5: Based on all the original output data obtained, the coefficients of α, β, γ, and δ are fitted using the least squares method.

9. A method for manufacturing a line tension measuring sensor, used to manufacture the line tension measuring sensor according to any one of claims 1-8, characterized in that, Includes the following steps: S1: First, apply glass slurry to four symmetrically arranged preset areas on the upper surface of the elastomer (10) made of 17-4PH stainless steel, and then dry the glass slurry to remove the organic carrier; the elastomer (10) has a mounting hole (11) in the center, and the four preset areas are located on both sides of the mounting hole (11). S2: Next, a uniaxial silicon piezoresistive MEMS chip (12) is attached to each glass paste. S3: Sinter the uniaxial silicon piezoresistive MEMS chip (12) in a chain sintering furnace, wherein the heating rate is between 5 and 10℃ / min; the holding temperature is between 450℃ and 500℃; the holding time is between 20 and 40 min; nitrogen or argon gas is used for protection; slow cooling rate: ≤3℃ / min; S4: Assemble the elastomer (10) with the box body 20. The upper surface of the box body (20) is provided with a first recess (22), and the bottom surface of the first recess (22) is provided with a second recess (23). The bottom surface of the first recess (22) is provided with first fixing holes (220) on the left and right sides of the second recess (23), and the two ends of the elastomer (10) are respectively installed in the first fixing holes (221) during assembly; The bottom surface of the first recess (22) is provided with second fixing holes (221) on the left and right sides of the second recess (23), respectively. The second fixing holes (221) are below the first fixing hole (220), and circuit boards (29) are fixed in the two second fixing holes (221). The circuit board (29) is provided with a signal processing circuit (290), an MCU control circuit (291), a voltage regulator circuit (294), a serial port circuit (292), and a communication interface (293); the communication interface (293) includes two communication terminals, a power supply terminal, and a ground terminal; the two communication terminals are electrically connected to the serial port circuit (292); the power supply terminal is used to provide power supply voltage; the ground terminal is used for grounding; The voltage regulator circuit (294) is electrically connected to the power supply terminal of the communication interface (293). The power supply voltage of the power supply terminal of the communication interface provides the operating voltage for the signal processing circuit (290), the MCU control circuit (291), and the serial port circuit (292). The signal processing circuit (290) is used to convert the analog signal output by the Wheatstone bridge into a digital signal. The MCU control circuit (291) processes the digital signal to obtain the line tension detection value and outputs it through the serial port circuit (292). The bottom surface of the second recess (23) is provided with a shock-absorbing block (24) integrally formed with the upper wall of the second recess (23); the shock-absorbing block (24) is provided with a sliding pull rod (25), the pull rod (25) passes through the box body (20) and has a through hole (250) at one end outside the box body (20), and the bottom surface of the pull rod (25) has an inward groove; The pull rod (26) is passed through the mounting hole (21), and one end of the pull rod (26) is threaded into the groove, while the other end of the pull rod (26) abuts against the lower surface of the elastomer 10. S5: Install the lid (21) on the top surface of the box body (20) to form a fixed box (2).

10. A method for manufacturing a line tension measuring sensor according to claim 9, characterized in that, Before performing step S1, the elastomer (10) is first laser cleaned to remove surface oil and oxide layer. Then, the surface of the elastomer (10) is activated to improve surface energy and increase the adhesion of glass paste. Finally, positioning marks are set on the surface of the elastomer (10). The positioning marks are used to locate the attachment position of the uniaxial silicon piezoresistive MEMS chip (12).

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