Quality evaluation method for pull rope sensor

Abstract

The invention relates to a quality evaluation method of a pull rope sensor. The quality evaluation method comprises the following steps: constructing an evaluation index system structure of the pull rope sensor; configuring a weight corresponding to each level of index in the evaluation index system structure; according to the test method and the scoring method of each level of index, obtaining a corresponding index score, and calculating to obtain a quality index score; and judging the quality performance of the pull rope sensor to be detected. Compared with the prior art, the method has the advantages of being comprehensive in consideration, conforming to reality, easy to standardize and the like.

Description

Technical Field

[0001] The present invention relates to the field of sensor detection, and in particular to a quality evaluation method for a drawstring sensor. Background Art

[0002] A draw-wire sensor, also known as a pull-wire sensor or length displacement sensor, is a detection instrument used to measure length. Currently, the quality inspection of draw-wire sensors involves many aspects, including temperature, humidity, vibration, etc. However, due to the wide variety of test contents, the inspection and evaluation methods of various manufacturers are also different. In addition, the country has not yet issued relevant standards for the inspection of draw-wire sensors. As a result, there is no quantitative, accurate, and comprehensive evaluation method for the quality of draw-wire sensors to provide data support for subsequent research and development improvements and factory inspections. Therefore, it is necessary to develop a quality evaluation method for draw-wire sensors. Summary of the Invention

[0003] To solve the technical problems in the background technology, the present invention provides a quality evaluation method for a draw wire sensor, comprising the following steps:

[0004] Construct an evaluation index system architecture for drawstring sensors;

[0005] Configuring the weights corresponding to the indicators at each level in the evaluation indicator system architecture;

[0006] Obtain the corresponding indicator scores according to the test methods and scoring methods of the indicators at each level, and calculate the quality indicator scores;

[0007] Determine the quality performance of the draw wire sensor under test.

[0008] Furthermore, the evaluation index system architecture specifically includes four-level evaluation indicators, with quality indicator A as the first-level evaluation indicator, and the second-level evaluation indicators under the first-level evaluation indicator include performance indicator B1, reliability and durability indicator B2, safety and compliance indicator B3, and user experience and functionality indicator B4.

[0009] Furthermore, the three-level indicators under the performance indicator B1 include:

[0010] Temperature stability index C1, anti-interference ability index C2, resolution index C3, nonlinearity index C4, repeatability index C5 and zero point deviation index C6;

[0011] The three-level indicators under the reliability and durability indicator B2 include:

[0012] Working life index C7, environmental adaptability index C8, and mechanical strength and packaging index C9;

[0013] The three-level indicators under the safety and compliance indicator B3 include:

[0014] Electrical safety indicator C10 and regulatory certification indicator C11;

[0015] The three-level indicators under the user experience and functionality indicator B4 include:

[0016] Installation convenience index C12 and signal output compatibility index C13.

[0017] Furthermore, the four-level indicators under the temperature stability index C1 include the zero drift index D1 and the thermal zero drift index D2; the four-level indicators under the anti-interference ability index C2 include the electrostatic discharge immunity index D3, the electrical fast transient pulse group immunity index D4 and the surge / shock immunity index D5;

[0018] The four-level indicators under the working life index C7 include the fatigue life index D6 of the spring mechanism and the expansion and contraction cycle and performance degradation distribution index D7; the four-level indicators under the environmental adaptability index C8 include the high-temperature storage index D8, the low-temperature storage index D9, the temperature shock index D10, the temperature cycle index D11, the humidity and heat index D12, the low-pressure index D13, the mold index D14, the salt spray index D15, the vibration index D16, the impact index D17 and the protection index D18; the four-level indicators under the mechanical strength and packaging index C9 include the pull-out force index D19 after full scale, the wire rope breaking force index D20, the free fall index D21 and the transportation vibration index D22;

[0019] The four-level indicators under the electrical safety index C10 include the voltage withstand level index D23, the overload protection function index D24, the anti-reverse connection function index D25 and the load dump protection index D26; the four-level indicators under the regulatory certification index C11 include the CE certification index D27, the PL certification index D28 and the explosion-proof certification index D29.

[0020] Furthermore, weights are assigned according to the importance of the indicators at each level.

[0021] Furthermore, for the weights of the secondary indicators, performance parameter indicator B1>safety and compliance indicator B3>reliability and durability indicator B2>user experience and functionality indicator B4.

[0022] Furthermore, after obtaining the scores of the four-level indicators, the scores of the third-level indicators, the second-level indicators, and the first-level indicators are calculated by weighted summation, and then:

[0023] A=α1B1+α2B2+α3B3+α4B4

[0024] B1=β1C1+β2C2+β3C3+β4C4+β5C5+β6C6

[0025] C1=δ1D1+δ2D2

[0026] C2=δ3D3+δ4D4+δ5D5

[0027] B2=β7C7+β8C8+β9C9

[0028] C7=δ6D6+δ7D7

[0029] C8=δ8D8+δ9D9+δ 10 D10+δ 11 D11+δ 12 D12+δ 13 D13

[0030] +δ 14 D14+δ 15 D15+δ 16 D16+δ 17 D17+δ 18 D18

[0031] C9=δ 19 D19+δ 20 D20+δ 21 D21+δ 22 D22

[0032] B3=β 10 C10+β 11 C11

[0033] C10=δ 23 D23+δ 24 D24+δ 25 D25+δ 26 D26

[0034] C11=δ 27 D27+δ 28 D28+δ 29 D29

[0035] B4=β 12 C12+β 13 C13

[0036] Among them, A is the score of the first-level indicator, B1~B4 are the scores of the second-level indicators, α1~α4 are the weights corresponding to the second-level indicators, C1~C13 are the scores of the third-level indicators, β1~β 13 are the weights corresponding to the three-level indicators, D1~D29 are the scores of the four-level indicators, δ1~δ 29are the weights corresponding to the four-level indicators respectively.

[0037] Furthermore, the quality performance of the draw wire sensor to be tested is comprehensively judged based on the quality index score combined with the scores of the four-level indicators.

[0038] Furthermore, for the drawstring sensor to be tested:

[0039] If the quality index A is not less than 90 points, and the scores of the four-level indicators D1 to D29 are not less than 75 points, the quality performance of the draw wire sensor to be tested is judged to be excellent;

[0040] If the quality index A is less than 90 points and not less than 75 points, and the scores of the four-level indicators D1 to D29 are not less than 75 points, then the quality performance of the draw wire sensor to be tested is judged to be qualified;

[0041] If the quality index A is less than 75 points, it is judged that the quality performance of the draw wire sensor to be tested is unqualified.

[0042] Furthermore, when the score of quality indicator A is not less than 75 points, if at least one of the scores of the four-level indicators D1 to D29 is lower than 75 points, the quality performance of the tested rope sensor is judged to be unqualified.

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

[0044] The present invention provides a quality evaluation method for draw-wire sensors. The method can perform quantitative quality assessment on various types of draw-wire sensors and use this to determine whether they are qualified. The four-level evaluation index system constructed in the method takes into account all aspects of the capabilities of the draw-wire sensors, and is comprehensive and covers a wide range. The present invention also assigns corresponding weights according to the degree of influence of each indicator on the quality, reflecting the emphasis of the draw-wire sensor on quality considerations. The evaluation is accurate and easy to standardize. In addition, the present invention also fills the relevant technical gaps in draw-wire sensor detection, which is conducive to the technological progress and development of the industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a flow chart of the steps of a quality evaluation method for a draw wire sensor proposed by the present invention. DETAILED DESCRIPTION

[0046] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0047] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0048] In the description of this embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0049] The terms “first”, “second”, etc. are only used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0050] In the description of this embodiment, it should be noted that, unless otherwise specified or limited, the terms "disposed," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this embodiment based on specific circumstances.

[0051] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0052] Example

[0053] like Figure 1 As shown, the present invention provides a quality evaluation method for a draw string sensor, which is used to achieve quantitative quality evaluation of draw string sensor samples or products during the research, development and production process of the draw string sensor, and can improve the draw string sensor samples or products based on the quantitative quality evaluation results to improve the quality or performance of the draw string sensor samples or products.

[0054] The quality evaluation method of the draw wire sensor provided by the present invention specifically includes the following steps:

[0055] 1. Construct a multi-level evaluation index system for rope-drawing sensors;

[0056] 1) First, based on the relationship and importance of the various indicators of the draw-wire sensor, a four-level evaluation indicator system architecture was constructed. Quality indicator A was used as the first-level evaluation indicator to comprehensively reflect the quality of the draw-wire sensor under test. Under the first-level evaluation indicator, there are four second-level indicators: performance indicator B1, reliability and durability indicator B2, safety and compliance indicator B3, and user experience and functionality indicator B4. These indicators are used to reflect the detection performance, reliability performance, safety performance, and functional performance of the draw-wire sensor, respectively.

[0057] The following introduces the third-level indicators and fourth-level indicators under the performance indicators, as well as the corresponding test methods and specific scores.

[0058] 1. Performance index B1

[0059] As shown in Table 1, performance index B1 includes six third-level indicators: temperature stability index C1, anti-interference ability index C2, resolution index C3, nonlinearity index C4, repeatability index C5 and zero point deviation index C6. The test methods and scoring methods for each third-level indicator are described in detail below.

[0060] Table 1 Performance indicators

[0061]

[0062] 1.1 Temperature stability index C1

[0063] This indicator includes two four-level indicators: zero drift indicator D1 and thermal zero drift indicator D2.

[0064] For the zero drift index D1, the specific test method is as follows: place the draw-wire sensor sample under standard atmospheric conditions to allow it to reach thermal equilibrium before conducting the test; unless otherwise specified, the temperature fluctuation during the test is no more than 2°C, and the state is maintained unchanged. Measure the zero output value of the draw-wire sensor and test according to the set test time and time interval. Generally, the test time is no less than 8 hours. Calculate the zero drift (measured value) of the draw-wire sensor in accordance with the provisions of "GB / T 18549-2001 - Calculation Method of Main Static Performance Indicators of Sensors", and then:

[0065]

[0066] Where D0 is the zero point drift, Δy0 is the initial zero point output, and Y FS is the full-scale output value.

[0067] The specific scoring method for this indicator is as follows:

[0068] 100 points: measured value ≤ design value;

[0069] 75 points: Design value < measured value ≤ design value * 120%;

[0070] 60 points: design value*120%<measured value≤design value*150%;

[0071] 0 points: Design value*150%<measured value.

[0072] For the thermal zero drift index D2, the specific test method is: place the drawstring sensor sample in a high and low temperature test chamber with a reference temperature of (25±2)°C. Set temperature test points (including at least the reference temperature, the upper and lower operating temperatures of the drawstring sensor). Increase or decrease the temperature of the high and low temperature test chamber, and maintain a constant temperature for 1 hour at each temperature test point. Test the zero point output (measured value) of the drawstring sensor at each temperature test point. Calculate the thermal zero drift (measured value) of the drawstring sensor in accordance with the provisions of "GB / T18549-2001 - Calculation Method for Main Static Performance Indicators of Sensors". The result is:

[0073]

[0074] Where γ is the thermal zero drift, The average zero-point output value, Y, is at temperatures T2 and T1 respectively. FS(T1) is the theoretical full-scale output at temperature T1.

[0075] The specific scoring method for this indicator is as follows:

[0076] 100 points: measured value ≤ design value;

[0077] 75 points: Design value < measured value ≤ design value * 120%;

[0078] 60 points: design value*120%<measured value≤design value*150%;

[0079] 0 points: Design value*150%<measured value.

[0080] 1.2 Anti-interference capability index C2

[0081] This indicator includes three four-level indicators: electrostatic discharge immunity indicator D3, electrical fast transient pulse group immunity indicator D4 and surge / shock immunity indicator D5.

[0082] For the electrostatic discharge immunity index D3, this index is used to indicate the performance of the draw wire sensor when subjected to electrostatic discharge. Specifically, the test method of contact discharge or air discharge is adopted. This index is determined according to the test level. The test level of contact discharge is divided into 4 levels (1, 2, 3, 4) corresponding to different test voltages (2, 4, 6, 8), and the test level of air discharge is divided into 4 levels (1, 2, 3, 4) corresponding to different test voltages (2, 4, 8, 15). The specific test method is as follows:

[0083] 1. Configure the test equipment in accordance with the provisions of GB / T 17626.2-2018 Electromagnetic compatibility test and measurement technology electrostatic discharge immunity test;

[0084] 2. The minimum size of the ground reference plane is 1 square meter. The actual size depends on the size of the draw wire sensor test piece. Each side should extend at least 0.5m outside the test equipment or the clamping plate and be connected to the protective grounding system.

[0085] 3. The minimum distance between the draw-wire sensor specimen and the laboratory wall and other metal structures is 1m;

[0086] 4. According to the installation technical conditions of the draw wire sensor sample, it should be connected to the grounding system; no other additional grounding connection wires are allowed;

[0087] 5. Electrostatic discharge is applied only to points and surfaces that the operator may touch during normal use of the draw-wire sensor test piece;

[0088] 6. The test should be carried out in single discharge mode. At least ten single discharges (the most sensitive polarity) should be applied at the preselected points.

[0089] 7. The time interval between consecutive single discharges is at least 1s.

[0090] For the electrical fast transient pulse group immunity index D4, this index is used to indicate the performance of the rope sensor when it is subjected to a point fast transient pulse. The specific test method is:

[0091] 1. Configure the test equipment in accordance with the provisions of the capacitive coupling clamp structure in "GB / T17626.4-2018-Electromagnetic compatibility test and measurement technology electrical fast transient burst immunity test";

[0092] 2. When the cable length between the draw-wire sensor sample and the output terminal of the coupling network exceeds 0.5m±0.05m, the excess length shall be folded in a non-inductive manner and placed together with the draw-wire sensor sample at 0.1m above the ground reference plane;

[0093] 3. Each side of the ground reference plane should extend at least 0.1m beyond the measured draw-wire sensor sample;

[0094] 4. Test the power port or other specified ports according to the specified test level requirements, and the test duration shall be at least 1 minute;

[0095] 5. Test twice, the first time with the product casing grounded, the second time without grounding, and both tests must meet the requirements.

[0096] For the surge / impact immunity index D5, the specific test method is:

[0097] 1. Configure the test equipment in accordance with the provisions of GB_T 17626.5-2019 Electromagnetic compatibility test and measurement technology surge (impact) immunity test;

[0098] 2. The number of surge pulses applied to the DC power supply terminal is 10 times each of positive and negative polarity;

[0099] 3. The time interval between successive pulses is 1 minute or less. (If a test with a repetition rate faster than 1 / min causes the draw-wire sensor under test to malfunction, but the draw-wire sensor under test works normally when tested at a repetition rate of 1 / min, use the repetition rate of 1 / min for testing.)

[0100] 4. When the cable length between the tested draw-wire sensor sample and the output end of the coupling network exceeds 1m, the excess length shall be folded in a non-sensing manner.

[0101] For the electrostatic discharge immunity index D3, the electrical fast transient pulse group immunity index D4 and the surge / impact immunity index D5, the three have the same scoring standards, namely:

[0102] 100 points: All functions of the draw wire sensor can be performed during and after the test and are within the permitted tolerances;

[0103] 75 points: All functions of the draw wire sensor can be performed during the test, but the performance of one or more functions is outside the tolerance range. After the test, all functions automatically return to normal.

[0104] 60 points: One or more functions of the drawstring sensor fail during the test, but all functions automatically return to normal after the test.

[0105] 0 points: One or more functions of the draw wire sensor fail during the test and cannot automatically return to normal after the test.

[0106] 1.3 Resolution index C3

[0107] The specific test method for this indicator is: fix the tested drawstring sensor sample on the fixture, select any test point between 10% and 90% of the sensor's measuring stroke (the recommended test point is near 50% of the measuring stroke), record the sensor's output value after the output stabilizes, and uniformly stretch the drawstring end of the tested drawstring sensor sample at a specified displacement to produce the minimum input (measured value) that produces an observable output change.

[0108] The specific scoring method for this indicator is as follows:

[0109] 100 points: measured value ≤ design value;

[0110] 75 points: Design value < measured value ≤ design value * 120%;

[0111] 60 points: design value*120%<measured value≤design value*150%;

[0112] 0 points: Design value*150%<measured value.

[0113] 1.4 Nonlinearity index C4

[0114] The specific test method for this indicator is: calculate and give the least squares straight line equation according to the provisions of "GB / T 18549-2001-Calculation Method of Main Static Performance Indicators of Sensors", and then calculate the linearity, then we have:

[0115]

[0116] Where, ξ L is the linearity, ΔY L,max Y is the maximum deviation of the actual characteristic curve of the draw wire sensor from the reference straight line, FS is the full-scale output of the draw-wire sensor.

[0117] The specific scoring method for this indicator is as follows:

[0118] 100 points: measured value ≤ design value;

[0119] 75 points: Design value < measured value ≤ design value * 120%;

[0120] 60 points: design value*120%<measured value≤design value*150%;

[0121] 0 points: Design value*150%<measured value.

[0122] 1.5 Repeatability index C5

[0123] According to the provisions of "GB / T 18549-2001 - Calculation Methods for Main Static Performance Indicators of Sensors," the repeatability of a draw-wire sensor at a certain calibration point can be calculated as the limit value of the sample standard deviation of a set of measurement values ​​at that calibration point at a certain confidence level, and expressed as a percentage of its full-scale output. The repeatability of a draw-wire sensor is taken as the maximum repeatability at each calibration point. The calculation formula is as follows:

[0124]

[0125] Where, ξ R is the repeatability, c is the coverage factor, S max is the maximum sample standard deviation, YFS is the full-scale output of the draw-wire sensor.

[0126] The specific scoring method for this indicator is as follows:

[0127] 100 points: measured value ≤ design value;

[0128] 75 points: Design value < measured value ≤ design value * 120%;

[0129] 60 points: design value*120%<measured value≤design value*150%;

[0130] 0 points: Design value*150%<measured value.

[0131] 1.6 Zero point deviation index C6

[0132] The specific test method for this indicator is: reset the wire rope pull ring of the tested wire rope sensor sample to the starting state as the sensor zero point, and record the sensor output value (measured value) at this time.

[0133] The specific scoring method for this indicator is as follows:

[0134] 100 points: measured value ≤ design value;

[0135] 75 points: Design value < measured value ≤ design value * 120%;

[0136] 60 points: design value*120%<measured value≤design value*150%;

[0137] 0 points: Design value*150%<measured value.

[0138] 2. Reliability and durability index B2

[0139] As shown in Table 2, the reliability and durability index B2 includes three third-level indicators: working life index C7, environmental adaptability index C8, and mechanical strength and packaging index C9. The test methods and scoring methods for each third-level indicator are described in detail below.

[0140] Table 2 Reliability and durability indicators

[0141]

[0142] 2.1 Working life index C7

[0143] The working life index C7 includes two four-level indicators: the fatigue life index D6 of the spring mechanism and the expansion and contraction cycle and performance degradation distribution index D7;

[0144] For the fatigue life indicator D6 of the spring mechanism, the test method for this indicator is as follows: the test rope sensor specimen is placed on the life tooling, the wire rope is pulled out to 95% of the full stroke at a speed of 1m / s and then reset to the starting state of suspension. This is a reciprocating motion until the spring mechanism of the sensor fails, and the total number of cycles (measured value) is recorded.

[0145] The specific scoring method for this indicator is as follows:

[0146] 100 points: measured value ≥ design value;

[0147] 75 points: Design value*80%≤measured value<design value;

[0148] 60 points: design value*75%≤measured value<design value*80%;

[0149] 0 points: Measured value < design value * 75%.

[0150] For the expansion and contraction cycle and performance attenuation distribution index D7, the specific test method for this index is as follows: before the test, the nonlinearity index of the tested rope sensor specimen is recorded, and then the tested rope sensor specimen is placed on the life test fixture for fatigue life test. The nonlinearity index of the sensor (actual measured value) is recorded after every 5,000 life tests until the spring mechanism of the sensor fails.

[0151] The specific scoring method for this indicator is as follows:

[0152] 100 points: measured value ≥ design value * (95%) n;

[0153] 75 points: design value * 80% * (95%) n ≤ measured value < design value * (95%) n;

[0154] 60 points: design value * 75% * (95%) n ≤ measured value < design value * 80% * (95%) n;

[0155] 0 points: measured value < design value * 75% * (95%) n;

[0156] Where n is the number of cycles of the 5000 life test.

[0157] 2.2 Environmental adaptability index C8

[0158] Environmental adaptability index C8 includes 11 four-level indicators: high-temperature storage index D8, low-temperature storage index D9, temperature shock index D10, temperature cycle index D11, humidity and heat index D12, low pressure index D13, mold index D14, salt spray index D15, vibration index D16, impact index D17 and protection index D18;

[0159] For the high temperature storage index D8, the test method for this index is as follows: in accordance with the test method specified in GBT 2423.2-2008 Environmental testing for electric and electronic products Part 2: Test methods Test B: High temperature and the following provisions:

[0160] A) The temperature is set to the upper limit of the storage temperature;

[0161] B) The test time is 8 hours;

[0162] C) After the test, restore to the standard atmospheric pressure of the experiment for 2 hours or as required by the relevant detailed specifications until the temperature of the specimen returns to room temperature, and then test the nonlinearity (measured value).

[0163] The specific scoring method for this indicator is as follows:

[0164] 100 points: measured value ≤ design value * 105%;

[0165] 75 points: design value * 105% < measured value ≤ design value * 120% * 105%;

[0166] 60 points: design value * 120% * 105% < measured value ≤ design value * 150% * 105%;

[0167] 0 points: Design value*150%*105%<measured value.

[0168] For the low temperature storage index D9, the specific test method for this index is: in accordance with the test method specified in "GBT 2423.1-2008 Environmental testing for electric and electronic products Part 2: Test methods Test A: Low temperature" and the following provisions:

[0169] A) The temperature is set to the lower limit of the storage temperature;

[0170] B) The test time is 8 hours;

[0171] C) After the test, restore to the standard atmospheric pressure of the experiment for 2 hours or as required by the relevant detailed specifications until the temperature of the specimen returns to room temperature, and then test the nonlinearity (measured value).

[0172] The specific scoring method for this indicator is as follows:

[0173] 100 points: measured value ≤ design value * 105%;

[0174] 75 points: design value * 105% < measured value ≤ design value * 120% * 105%;

[0175] 60 points: design value * 120% * 105% < measured value ≤ design value * 150% * 105%;

[0176] 0 points: Design value*150%*105%<measured value.

[0177] For the temperature shock index D10, the test method for this index is as follows: in accordance with the test method specified in "GBT 2423.22-2012 Environmental testing Part 2: Test method Test N: Temperature change" and the following provisions:

[0178] A) The temperature is set to the upper limit of the storage temperature and the lower limit of the storage temperature;

[0179] B) The test time at extreme temperature is 1h (or as specified in relevant detailed specifications);

[0180] C) The conversion time is no more than 3 minutes;

[0181] D) The number of cycles is not less than 5 times;

[0182] E) After the test, restore to the standard atmospheric pressure of the experiment for 2 hours or as required by the relevant detailed specifications until the temperature of the specimen returns to room temperature, and then test the nonlinearity (measured value).

[0183] The specific scoring method for this indicator is as follows:

[0184] 100 points: measured value ≤ design value * 105%;

[0185] 75 points: design value * 105% < measured value ≤ design value * 120% * 105%;

[0186] 60 points: design value * 120% * 105% < measured value ≤ design value * 150% * 105%;

[0187] 0 points: Design value*150%*105%<measured value.

[0188] For the temperature cycle index D11, the test method for this index is as follows: in accordance with the test method specified in "GBT 2423.22-2012 Environmental testing Part 2: Test method Test N: Temperature change" and the following provisions:

[0189] A) The temperature is set to the upper limit of the working temperature (temperature deviation ± 2 ° C) and the lower limit of the working temperature (temperature deviation ± 3 ° C);

[0190] B) Temperature change rate ≥ 10℃ / min;

[0191] C) Temperature holding time is 1h (or as specified in relevant detailed specifications);

[0192] D) The temperature cycle time is 4 hours for a complete cycle;

[0193] E) The number of cycles is not less than 5 times;

[0194] F) During the experiment, power is supplied according to the excitation power supply provisions in 4.3.1.2, and the zero-point output of the monitoring sensor shall comply with the provisions of the relevant detailed specifications;

[0195] G) After the test, restore to the standard atmospheric pressure of the experiment for 2 hours or as required by the relevant detailed specifications until the temperature of the specimen returns to room temperature, and then test the nonlinearity (measured value).

[0196] The specific scoring method for this indicator is as follows:

[0197] 100 points: measured value ≤ design value * 110%;

[0198] 75 points: design value * 110% < measured value ≤ design value * 120% * 110%;

[0199] 60 points: design value * 120% * 110% < measured value ≤ design value * 150% * 110%;

[0200] 0 points: Design value*150%*110%<measured value.

[0201] For the humidity and heat index D12, the specific test method for this index is: conduct the experiment in accordance with the provisions of "GBT 2423.3-2016 Environmental testing Part 2: Test method Test Cab: Steady humidity and heat test", and the test conditions shall be in accordance with the provisions of the relevant detailed specifications. After the test, recover for 2 hours under the standard atmospheric pressure of the experiment or in accordance with the provisions of the relevant detailed specifications until the specimen temperature returns to room temperature, and then detect the nonlinearity (measured value).

[0202] The specific scoring method for this indicator is as follows:

[0203] 100 points: measured value ≤ design value * 110%;

[0204] 75 points: design value * 110% < measured value ≤ design value * 120% * 110%;

[0205] 60 points: design value * 120% * 110% < measured value ≤ design value * 150% * 110%;

[0206] 0 points: Design value*150%*110%<measured value.

[0207] For the low pressure index D13, the specific test method for this index is: conduct the experiment according to the method specified in GB / T 2423.21-2008, the test conditions shall be in accordance with the provisions of the relevant detailed specifications, and the nonlinearity (measured value) shall be detected after the test.

[0208] The specific scoring method for this indicator is as follows:

[0209] 100 points: measured value ≤ design value * 105%;

[0210] 75 points: design value * 105% < measured value ≤ design value * 120% * 105%;

[0211] 60 points: design value * 120% * 105% < measured value ≤ design value * 150% * 105%;

[0212] 0 points: Design value*150%*105%<measured value.

[0213] The test method for mold index D14 is as follows: Conduct the experiment according to the method specified in GBT 2423.16-2008 Environmental testing for electrical and electronic products Part 2: Test methods, test J and guidance: Mold growth. The test strains are specified in the relevant detailed specifications. After the test, check whether the product meets the design requirements for salt spray level.

[0214] The specific scoring method for this indicator is as follows:

[0215] 100 points: no mold;

[0216] 75 points: not inferior to grade II;

[0217] 0 points: worse than grade II.

[0218] The test method for salt spray index D15 is as follows: Conduct the test according to the method specified in GBT 2423.17-2008 Environmental testing for electrical and electronic products - Part 2: Test methods, Test Ka: Salt spray. Test conditions are as specified in the relevant detailed specifications. After the test, check whether the product meets the design requirements for the salt spray level.

[0219] The specific scoring method for this indicator is as follows:

[0220] 100 points: no corrosion;

[0221] 75 points: corrosion area ≤ 5%;

[0222] 0 points: Corrosion area > 5%.

[0223] For vibration index D16, the test method for this index is as follows: the experiment is carried out in accordance with the method specified in "GBT 2423.10-2019 Environmental testing Part 2: Test method Test Fc vibration (sinusoidal)", the test conditions are in accordance with the provisions of the relevant detailed specifications, and the nonlinearity (measured value) is detected after the test.

[0224] The specific scoring method for this indicator is as follows:

[0225] 100 points: measured value ≤ design value * 105%;

[0226] 75 points: design value * 105% < measured value ≤ design value * 120% * 105%;

[0227] 60 points: design value * 120% * 105% < measured value ≤ design value * 150% * 105%;

[0228] 0 points: Design value*150%*105%<measured value.

[0229] For the impact index D17, the test method for this index is as follows: the experiment is carried out in accordance with the method specified in "GBT 2423.5-2019 Environmental testing Part 2: Test method Test Ea and guidance: Impact", the test conditions are in accordance with the provisions of the relevant detailed specifications, and the nonlinearity (measured value) is detected after the test.

[0230] The specific scoring method for this indicator is as follows:

[0231] 100 points: measured value ≤ design value * 105%;

[0232] 75 points: design value * 105% < measured value ≤ design value * 120% * 105%;

[0233] 60 points: design value * 120% * 105% < measured value ≤ design value * 150% * 105%;

[0234] 0 points: Design value*150%*105%<measured value.

[0235] For protection index D18, the test method for this index is as follows: conduct experiments in accordance with the method specified in "GB / T 4208-2017 Enclosure Protection Grades", and the test conditions shall be in accordance with the provisions of the relevant detailed specifications. After the test, check whether it meets the design requirements of the protection grade.

[0236] The specific scoring method for this indicator is as follows:

[0237] 100 points: Meets the protection level and no water or dust infiltration;

[0238] 75 points: Water or dust has penetrated, but communication output is normal;

[0239] 0 points: Water or dust has penetrated, and there is no communication output.

[0240] 2.3 Mechanical strength and packaging index C9

[0241] The mechanical strength and packaging index C9 includes four four-level indicators: pull-out force index D19 after full scale, wire rope breaking force index D20, free fall index D21 and transportation vibration index D22;

[0242] For the pull-off force index D19 after full scale, the test method of this index is as follows: install the tested rope sensor sample on the fixture, connect the rope end to the dynamometer, stretch the sensor at a uniform speed until the full scale is reached, continue to slowly stretch the tested rope sensor sample at a rate that can read the dynamometer indication until the rope is pulled off, and read the tension value (actual value) at this time.

[0243] The specific scoring method for this indicator is as follows:

[0244] 100 points: measured value ≥ design value;

[0245] 75 points: Design value*80%≤measured value<design value;

[0246] 60 points: design value*75%≤measured value<design value*80%;

[0247] 0 points: Measured value < design value * 75%.

[0248] For the wire rope breaking force index D20, the test method of this index is as follows: the length of the rope of the tested rope sensor sample participating in the test is not less than 300mm, one end of the rope is fixed, and the other end is connected to the dynamometer, and the full-scale pull-off force is applied. The rope should not break, and the tension is continued to be slowly applied at a rate that can read the tension indication until the rope breaks, and the tension value at this time (measured value) is read.

[0249] The specific scoring method for this indicator is as follows:

[0250] 100 points: measured value ≥ design value;

[0251] 75 points: Design value*80%≤measured value<design value;

[0252] 60 points: design value*75%≤measured value<design value*80%;

[0253] 0 points: Measured value < design value * 75%.

[0254] For the free fall index D21, the test method of this index is as follows: the rope sensor sample under test with transport packaging is subjected to a drop test, and the drop test is carried out on a concrete floor, with one drop on each corner for a total of 26 times. After the test, the sensor is checked for damage and whether its function is normal.

[0255] The specific scoring method for this indicator is as follows:

[0256] 100 points: The sensor is not damaged and the product functions normally;

[0257] 75 points: The sensor is slightly damaged and the product functions normally;

[0258] 0 points: The sensor is severely damaged or the product does not function properly.

[0259] For transport vibration index D22, the test method for this index is as follows:

[0260] The drawstring sensor sample under test is placed in a shipping box containing all packaging materials. The simulated state of the vibration table is close to reality, and direct fixation using pressure blocks or pressure strips is not used. The preferred fixing method is to install protective columns around the vibration table and provide good protection on all sides. The packaged drawstring sensor sample under test is placed directly in the middle and allowed to move freely, or it can be fixed with a binding tape. In principle, rigid fixation is not performed. After the test, the sensor is inspected for damage and normal function.

[0261] The specific scoring method for this indicator is as follows:

[0262] 100 points: The sensor is not damaged and the product functions normally;

[0263] 75 points: The sensor is slightly damaged and the product functions normally;

[0264] 0 points: The sensor is severely damaged or the product does not function properly.

[0265] 3. Security and Compliance Indicator B3

[0266] As shown in Table 3, the safety and compliance indicator B3 includes two third-level indicators: electrical safety indicator C10 and regulatory certification indicator C11. The test methods and scoring methods for each third-level indicator are described in detail below.

[0267] Table 3 Security and compliance indicators

[0268]

[0269] 3.1 Electrical safety index C10

[0270] This indicator includes four four-level indicators: voltage resistance indicator D23, overload protection function indicator D24, anti-reverse polarity function indicator D25 and load dump protection indicator D26. Each indicator should meet the test standards corresponding to the design requirements of the rope sensor. The specific scoring method of the indicators is as follows:

[0271] 100 points: This item is included in the design requirements of the draw wire sensor, and the product meets the test standards corresponding to the design requirements;

[0272] 75 points: The design requirements for draw wire sensors do not include this item;

[0273] 0 points: This item is included in the design requirements for the draw wire sensor, but the product does not meet the test standards corresponding to the design requirements.

[0274] 3.2 Regulatory Certification Index C11

[0275] This indicator includes three four-level indicators: CE certification indicator D27, PL certification indicator D28 and explosion-proof certification indicator D29. Each indicator should meet the standards corresponding to the design requirements of the rope sensor. The specific scoring method of the indicator is as follows:

[0276] 100 points: This item is included in the design requirements of the draw wire sensor, and the product meets the test standards corresponding to the design requirements;

[0277] 75 points: The design requirements for draw wire sensors do not include this item;

[0278] 0 points: This item is included in the design requirements for the draw wire sensor, but the product does not meet the test standards corresponding to the design requirements.

[0279] 4. User experience and functional indicators B4

[0280] As shown in Table 4, the user experience and functionality indicator B4 includes two third-level indicators: the installation convenience indicator C12 and the signal output compatibility indicator C13. The test methods and scoring methods for each third-level indicator are described in detail below.

[0281] Table 4 User experience and functional indicators

[0282]

[0283] Each of the three-level indicators should meet the standards corresponding to the design requirements of the draw-wire sensor. The specific scoring method for the indicators is as follows:

[0284] 100 points: This item is included in the design requirements of the draw wire sensor, and the product meets the test standards corresponding to the design requirements;

[0285] 75 points: The design requirements for draw wire sensors do not include this item;

[0286] 0 points: This item is included in the design requirements for the draw wire sensor, but the product does not meet the test standards corresponding to the design requirements.

[0287] 2. Assign weights to indicators at all levels according to their importance. The specific weights of each indicator are shown in Table 5.

[0288] Table 5 Weights of indicators at all levels

[0289]

[0290]

[0291]

[0292]

[0293] Table 5 only provides a preferred weight configuration scheme for draw-wire sensors. It is foreseeable that this method can reconfigure the corresponding indicator weights according to different models, different design requirements, and indicator emphases. For draw-wire sensors of different models and different design requirements, the corresponding weights of each indicator are also different. In addition to providing a specific example, Table 5 also reflects the importance of indicators at each level. In principle, the indicator weight of performance parameter indicator B1 is greater than the indicator weight of safety and compliance indicator B3, the indicator weight of reliability and durability indicator B2, and the indicator weight of user experience and functionality indicator B4.

[0294] 3. According to the test method and scoring method of each indicator in the multi-level evaluation index system of the draw wire sensor, the specific score of each indicator is obtained through the corresponding test, and the score of the quality index A is calculated by weighted summation, which is:

[0295] A=α1B1+α2B2+α3B3+α4B4

[0296] B1=β1C1+β2C2+β3C3+β4C4+β5C5+β6C6

[0297] C1=δ1D1+δ2D2

[0298] C2=δ3D3+δ4D4+δ5D5

[0299] B2=β7C7+β8C8+β9C9

[0300] C7=δ6D6+δ7D7

[0301] C8=δ8D8+δ9D9+δ 10 D10+δ 11 D11+δ 12 D12+δ 13 D13

[0302] +δ 14 D14+δ 15 D15+δ 16 D16+δ 17 D17+δ 18 D18

[0303] C9=δ 19 D19+δ 20 D20+δ 21 D21+δ 22 D22

[0304] B3=β 10 C10+β11 C11

[0305] C10=δ 23 D23+δ 24 D24+δ 25 D25+δ 26 D26

[0306] C11=δ 27 D27+δ 28 D28+δ 29 D29

[0307] B4=β 12 C12+β 13 C13

[0308] In the formula, B1~B4 are the scores of each secondary indicator, α1~α4 are the weights corresponding to each secondary indicator, C1~C13 are the scores of each tertiary indicator, β1~β 13 are the weights corresponding to the three-level indicators, D1~D29 are the scores of the four-level indicators, δ1~δ 29 are the weights corresponding to the four-level indicators respectively.

[0309] 4. After obtaining the quality index score of the current draw-wire sensor to be tested, the quality performance of the draw-wire sensor to be tested is judged, specifically:

[0310] I. If the quality index A is not less than 90 points, and the scores of the four-level indicators D1 to D29 are not less than 75 points, the quality performance of the draw wire sensor to be tested is judged to be excellent;

[0311] II. If the quality index A is less than 90 points and not less than 75 points, and the scores of the four-level indicators D1 to D29 are not less than 75 points, then the quality performance of the draw wire sensor to be tested is judged to be qualified;

[0312] III. If the quality index A is less than 75 points, the quality performance of the draw wire sensor to be tested is judged to be unqualified;

[0313] In addition, for I and II, if the score of quality indicator A is not less than 75 points, but at least one of the scores of the four-level indicators D1 to D29 is lower than 75 points, the quality performance of the tested rope sensor is also judged to be unqualified.

[0314] For example, a newly developed drawstring sensor sample is evaluated according to the quality evaluation method provided by the present invention. First, the scoring standard (design value) corresponding to each indicator in the multi-level evaluation index system is confirmed according to the model of the drawstring sensor. Then, the test is carried out according to the test method corresponding to each indicator to obtain the corresponding third-level / fourth-level indicator score. Then, the weighted summation method is used to calculate the scores of the second-level and first-level indicators in turn. Finally, the scores of the first-level and fourth-level indicators are combined to judge the quality performance of the drawstring sensor sample. The design defects found serve as the basis for subsequent design improvements to improve product quality.

[0315] In summary, the present invention provides a quality evaluation method for draw-wire sensors, which can perform quantitative quality assessment on various types of draw-wire sensors and use this to determine whether they are qualified. The four-level evaluation index system constructed in this method takes into account all aspects of the capabilities of the draw-wire sensors, and is comprehensive and covers a wide range. The present invention also assigns corresponding weights according to the degree of influence of each indicator on the quality, reflecting the emphasis of the draw-wire sensor on quality considerations, and the evaluation is accurate and easy to standardize. In addition, the present invention also fills the relevant technical gaps in draw-wire sensor detection, which is conducive to technological progress and development in the industry.

[0316] Numerous modifications and variations can be made based on the concepts of the present invention without inventive effort. Therefore, any technical solution that can be derived by a person skilled in the art based on the concepts of the present invention through logical analysis, reasoning, or limited experimentation based on the existing technology should be within the scope of protection defined by the claims. The preferred embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art would be able to do so.

Claims

1. A method for evaluating the quality of a draw-wire sensor, characterized in that: The following steps are involved: Construct an evaluation index system architecture for drawstring sensors; Configuring the weights corresponding to the indicators at each level in the evaluation indicator system architecture; Obtain the corresponding indicator scores according to the test methods and scoring methods of the indicators at each level, and calculate the quality indicator scores; Determine the quality performance of the draw wire sensor under test.

2. The quality evaluation method of a draw wire sensor according to claim 1, characterized in that: The evaluation index system structure specifically includes four-level evaluation indicators, with quality indicator A as the first-level evaluation indicator, and the second-level evaluation indicators under the first-level evaluation indicator include performance indicator B1, reliability and durability indicator B2, safety and compliance indicator B3 and user experience and functionality indicator B4.

3. The quality evaluation method of a draw wire sensor according to claim 2, characterized in that: The three-level indicators under performance indicator B1 include: Temperature stability index C1, anti-interference ability index C2, resolution index C3, nonlinearity index C4, repeatability index C5 and zero point deviation index C6; The three-level indicators under the reliability and durability indicator B2 include: Working life index C7, environmental adaptability index C8, and mechanical strength and packaging index C9; The three-level indicators under the safety and compliance indicator B3 include: Electrical safety indicator C10 and regulatory certification indicator C11; The three-level indicators under the user experience and functionality indicator B4 include: Installation convenience index C12 and signal output compatibility index C13.

4. The quality evaluation method of a draw wire sensor according to claim 3, characterized in that: The four-level indicators under the temperature stability index C1 include the zero drift index D1 and the thermal zero drift index D2; the four-level indicators under the anti-interference ability index C2 include the electrostatic discharge immunity index D3, the electrical fast transient pulse group immunity index D4 and the surge / shock immunity index D5; The four-level indicators under the working life index C7 include the fatigue life index D6 of the spring mechanism and the expansion and contraction cycle and performance degradation distribution index D7; the four-level indicators under the environmental adaptability index C8 include the high-temperature storage index D8, the low-temperature storage index D9, the temperature shock index D10, the temperature cycle index D11, the humidity and heat index D12, the low-pressure index D13, the mold index D14, the salt spray index D15, the vibration index D16, the impact index D17 and the protection index D18; the four-level indicators under the mechanical strength and packaging index C9 include the pull-out force index D19 after full scale, the wire rope breaking force index D20, the free fall index D21 and the transportation vibration index D22; The four-level indicators under the electrical safety index C10 include the voltage withstand level index D23, the overload protection function index D24, the anti-reverse connection function index D25 and the load dump protection index D26; the four-level indicators under the regulatory certification index C11 include the CE certification index D27, the PL certification index D28 and the explosion-proof certification index D29.

5. The quality evaluation method of a draw wire sensor according to claim 4, characterized in that: Weights are assigned according to the importance of the indicators at each level.

6. The quality evaluation method of a draw wire sensor according to claim 5, characterized in that: Regarding the weights of the secondary indicators, performance parameter indicator B1>safety and compliance indicator B3>reliability and durability indicator B2>user experience and functionality indicator B4.

7. The quality evaluation method of a draw wire sensor according to claim 5, characterized in that: After obtaining the scores of each of the four-level indicators, the scores of the third-level indicator, the second-level indicator, and the first-level indicator are calculated using a weighted summation method, and then: A=α1B1+α2B2+α3B3+α4B4 B1=β1C1+β2C2+β3C3+β4C4+β5C5+β6C6 C1=δ1D1+δ2D2 C2=δ3D3+δ4D4+δ5D5 B2=β7C7+β8C8+β9C9 C7=δ6D6+δ7D7 C8=δ8D8+δ9D9+δ 10 D10+d 11 D11+d 12 D12+d 13 D13 +d 14 D14+d 15 D15+d 16 D16+d 17 D17+d 18 D18 C9=δ 19 D19+d 20 D20+d 21 D21+d 22 D22 B3=β 10 C10+β 11 C11 C10=δ 23 D23+d 24 D24+d 25 D25+d 26 D26 C11=δ 27 D27+d 28 D28+d 29 D29 B4=β 12 C12+β 13 C13 Among them, A is the score of the first-level indicator, B1~B4 are the scores of the second-level indicators, α1~α4 are the weights corresponding to the second-level indicators, C1~C13 are the scores of the third-level indicators, β1~β 13 are the weights corresponding to the three-level indicators, D1~D29 are the scores of the four-level indicators, δ1~δ 29 are the weights corresponding to the four-level indicators respectively.

8. The quality evaluation method of a draw wire sensor according to claim 7, characterized in that: The quality performance of the draw wire sensor to be tested is comprehensively judged based on the quality index score combined with the scores of the four-level indicators.

9. The quality evaluation method of a draw wire sensor according to claim 8, characterized in that: For the draw wire sensor to be tested: If the quality index A is not less than 90 points, and the scores of the four-level indicators D1 to D29 are not less than 75 points, the quality performance of the draw wire sensor to be tested is judged to be excellent; If the quality index A is less than 90 points and not less than 75 points, and the scores of the four-level indicators D1 to D29 are not less than 75 points, then the quality performance of the draw wire sensor to be tested is judged to be qualified; If the quality index A is less than 75 points, it is judged that the quality performance of the draw wire sensor to be tested is unqualified.

10. The quality evaluation method of a draw wire sensor according to claim 9, characterized in that: When the score of quality indicator A is not less than 75 points, if at least one of the scores of the four-level indicators D1 to D29 is lower than 75 points, the quality performance of the tested rope sensor is judged to be unqualified.

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