Compensation method for a standard dynamometer under temperature gradient

Abstract

The present application relates to standard dynamometer manufacturing technical field, specifically, it relates to a kind of compensation method of standard dynamometer under temperature gradient.The method is measured by constructing partial pressure voltage network before, ensure the stability of output voltage proportion, and through the curve of the sensitivity of standard dynamometer with time compensation, and the compensation coefficient is calculated to compensate, the accurate compensation of standard dynamometer under specific temperature condition is realized.Through real-time monitoring ambient temperature and time, according to change combines correction curve correction standard dynamometer output, so as to achieve the purpose of correcting its system error, ensure that the superimposed force standard machine still outputs accurate, reliable data under the condition of temperature deviation.

Description

Technical Field

[0001] This invention relates to the field of standard force gauge manufacturing technology, and more specifically, to a compensation method for a standard force gauge under a temperature gradient. Background Technology

[0002] The superimposed force standard machine is a metrological standard device developed based on Newton's third law. Unlike static gravity force standard machines and lever force standard machines, the superimposed force standard machine has a smaller size and weight because its reference standard is a standard force measuring instrument with a certain accuracy, making it suitable for use in production and testing sites. Its working principle involves using a standard force measuring instrument with higher accuracy than the equipment being measured as a reference standard. This instrument is connected in series with the equipment through a series of frames and fixtures, and the load is applied hydraulically or mechanically. Metrologists evaluate the accuracy of the equipment being measured by comparing the consistency of the output values ​​of the standard force measuring instrument and the equipment being measured.

[0003] Because the reference standard for a superimposed force standard machine is a standard force gauge, the accuracy of its readings is significantly affected by temperature. It is not as stable as the readings of a static gravity force standard machine using weights or a lever-based force standard machine using levers. Therefore, due to the influence of temperature, the industry currently tends to use superimposed force standard machines in laboratory environments. This practice, to some extent, limits the expansion of their application scenarios. Many factors influence the accurate measurement of a force standard machine. Currently, the industry is researching some of the more influential factors. For example, the patent "A Static Gravity Force Standard Machine and Its Force Value Correction Method" from the Tianjin Institute of Metrology and Testing mentions compensation and correction methods for factors such as air buoyancy, humidity, and temperature.

[0004] Among a series of factors that may limit the application scenarios of superimposed force standards, temperature has a relatively significant impact. This is because the force measurement of a standard force gauge is based on the deformation of strain resistance wires attached to an elastic body: at the center of the standard force gauge is an elastic body that undergoes standard deformation under load, and the magnitude of its strain almost exactly corresponds to the magnitude of the load. Therefore, the load value applied to it can be obtained by measuring the strain value of the elastic body. To measure its minute strain, one or more extremely fine foil resistance wires are usually attached to the elastic body. Each resistance wire, together with three other unattached resistors, forms a circuit called a Wheatstone bridge, used to measure the micro-resistance change. The measured data is acquired by an AD chip, and the amount of data acquired by the AD chip depends on the chip's bit depth, input voltage value, and reference voltage value.

[0005] However, in actual measurement work, foil resistance wires are highly sensitive to temperature changes, and the measurement of the input and reference voltages of the AD chip is also affected by the ambient environment. Temperature deviations from the standard environment will cause inaccurate voltage and resistance measurements. Therefore, national metrological regulations require that the stacking machine should be used in an environment of (20±5)℃. However, for weighing sensors, force sensors, and force measuring instruments used in production sites, in many cases, on-site metrological calibration is required. However, the temperature in production sites often exceeds the standard temperature requirements, which leads to system metrological errors. Summary of the Invention

[0006] To address the issue of system measurement errors caused by temperatures frequently exceeding standard temperature requirements at production sites, this invention proposes a compensation method for a standard force gauge under temperature gradients. Before measurement, a voltage divider network is constructed to ensure the stability of the output voltage ratio. The compensation coefficient is calculated based on the sensitivity curve of the standard force gauge over time, achieving accurate compensation of the standard force gauge under specific temperature conditions. By real-time monitoring of ambient temperature and time, and adjusting the standard force gauge output based on changes and a correction curve, the system error is corrected, ensuring that the superimposed force standard machine still outputs accurate and reliable data even with temperature deviations.

[0007] The specific implementation details of this invention are as follows:

[0008] A compensation method for a standard force gauge under a temperature gradient, the standard force gauge comprising an elastomer and a foil resistance wire, the method specifically comprising the following steps:

[0009] Step 1: Construct a resistance voltage divider network on the variable bridge arm of the foil resistance wire of the standard force gauge, and adjust the micro resistance change of the variable bridge arm.

[0010] Step 2: Set the temperature test chamber to room temperature, use a standard force gauge equipped with a temperature test chamber to load the standard force gauge to its rated load, collect the change in sensitivity of the standard force gauge within a set time interval until the change in sensitivity remains constant, and plot the curve a of the sensitivity change over time.

[0011] Step 3: Set the temperature test chamber to the set temperature, load the standard force gauge to the rated load, collect the change in sensitivity of the standard force gauge within the set time interval until the change in sensitivity remains constant, and plot the curve b of the sensitivity change over time.

[0012] Step 4: Calculate the rate of change of sensitivity at the same time point based on curve a and curve b;

[0013] Step 5: Using the sensitivity change rate as the vertical axis and the set time interval as the horizontal axis, obtain the sensitivity compensation curve of the standard force measuring instrument over time, and calculate the compensation coefficient of the sensitivity compensation curve over time.

[0014] Step 6: Calculate the compensated standard force value based on the compensation coefficient.

[0015] To better realize the present invention, the resistor voltage divider network constructed in step 1 further includes a positive input unit, a voltage divider unit, and a negative input unit;

[0016] The input terminal of the positive input unit is connected to the positive terminal of the power supply, and the output terminal is connected to the input terminal of the voltage divider unit.

[0017] The input terminal of the negative input unit is connected to the negative terminal of the power supply, and the output terminal is connected to the input terminal of the voltage divider unit.

[0018] The positive input unit includes a resistor R1; the negative input unit includes a resistor R2; the voltage divider unit includes N voltage divider units, where N is an even number greater than or equal to 2;

[0019] Each of the N voltage divider units includes n resistors R0 connected in parallel;

[0020] The resistance values ​​and temperature coefficients of resistors R1, R2, and R0 are all the same.

[0021] To better realize the present invention, the specific operation of adjusting the micro resistance change of the variable bridge arm in step 1 is as follows: according to the constructed resistor voltage divider network and the number N of the voltage divider units, the output voltage is divided into N / 2 levels, and the micro resistance change of the variable bridge arm is adjusted by adjusting the number of resistors R0 in the voltage divider units.

[0022] To better realize the present invention, the specific operation of calculating the rate of change of sensitivity at the same time point in step 4 is as follows:

[0023]

[0024] Where, θ bi For t i Sensitivity at time b under curve θ ai For t i Sensitivity at time a under curve a, k i This represents the rate of change in sensitivity.

[0025] To better realize the present invention, step 6 is further described as follows: obtaining the time difference Δt between the standard force measuring instrument moving from the placement point to the measurement point; obtaining the compensation coefficient based on the time difference Δt and the curve of sensitivity compensation over time; and calculating the compensated standard force value based on the compensation coefficient.

[0026] To better realize the present invention, the specific operation of calculating the compensated standard force value is further as follows:

[0027] F = F i (1+k)

[0028] Where F represents the compensated standard force value; F i The value represents the standard value of the standard force gauge during compensation; k represents the compensation coefficient.

[0029] The present invention has the following beneficial effects:

[0030] (1) This invention provides a reliable, time-dependent, and repeatable compensation method for standard force gauges applied to production sites where the temperature deviates from the standard environment, ensuring the accuracy and reliability of the output data of the standard force gauges in production sites with temperature deviations.

[0031] (2) By constructing a resistor voltage divider network, the present invention enables the voltage and resistance values ​​to be acquired without being affected by the environment, thus eliminating the interference of the production site on the measurement excitation end.

[0032] (3) The present invention uses the curve of the sensitivity of the standard force gauge over time to compensate and calculates the compensation coefficient to compensate, thereby achieving accurate compensation of the standard force gauge under specific temperature conditions. Attached Figure Description

[0033] Figure 1 A schematic diagram of the voltage divider circuit network provided in the embodiments of this application;

[0034] Figure 2 The schematic diagram of the standard Wheatstone bridge circuit provided for the embodiments of this application;

[0035] Figure 3 The equivalent Wheatstone bridge circuit schematic provided in the embodiments of this application;

[0036] Figure 4 This is a schematic diagram of the sensitivity change over time under a specific temperature gradient, provided in an embodiment of this application. Detailed Implementation

[0037] To more clearly illustrate the technical solutions of the embodiments of the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments, and therefore should not be regarded as a limitation on the scope of protection. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0039] Example 1:

[0040] This embodiment proposes a compensation method for a standard force gauge under a temperature gradient. The standard force gauge includes an elastomer and a foil resistance wire, and specifically includes the following steps.

[0041] Step 1: Construct a resistance voltage divider network on the variable bridge arm of the foil resistance wire of the standard force gauge, and adjust the micro resistance change of the variable bridge arm.

[0042] like Figure 1 As shown, the resistor voltage divider network constructed in step 1 includes a positive input unit, a voltage divider unit, and a negative input unit;

[0043] The input terminal of the positive input unit is connected to the positive terminal of the power supply, and the output terminal is connected to the input terminal of the voltage divider unit.

[0044] The input terminal of the negative input unit is connected to the negative terminal of the power supply, and the output terminal is connected to the input terminal of the voltage divider unit.

[0045] The positive input unit includes a resistor R1; the negative input unit includes a resistor R2; the voltage divider unit includes N voltage divider units, where N is an even number greater than or equal to 2;

[0046] Each of the N voltage divider units includes n resistors R0 connected in parallel;

[0047] The resistance values ​​and temperature coefficients of resistors R1, R2, and R0 are all the same.

[0048] Further, the specific operation of adjusting the micro-resistance change of the variable bridge arm in step 1 is as follows: based on the constructed resistor voltage divider network and the number N of the voltage divider units, the output voltage is divided into N / 2 levels, and the micro-resistance change of the variable bridge arm is adjusted by adjusting the number of resistors R0 in the voltage divider units.

[0049] Step 2: Set the temperature test chamber to room temperature, use a standard force gauge equipped with a temperature test chamber to load the standard force gauge to its rated load, collect the change in sensitivity of the standard force gauge within a set time interval until the change remains constant, and plot the curve a of the sensitivity change over time.

[0050] Step 3: Set the temperature test chamber to the set temperature, load the standard force gauge to the rated load, collect the change in sensitivity of the standard force gauge within the set time interval until the change remains constant, and plot the curve b of the sensitivity change over time.

[0051] Step 4: Calculate the rate of change of sensitivity at the same time point based on curve a and curve b.

[0052] Furthermore, the specific operation for calculating the rate of change of sensitivity at the same time point in step 4 is as follows:

[0053]

[0054] Where, θ bi For t i Sensitivity at time b under curve θ ai For t i Sensitivity at time a under curve a, k i This represents the rate of change in sensitivity.

[0055] Step 5: Using the sensitivity change rate as the vertical axis and the set time interval as the horizontal axis, obtain the sensitivity compensation curve of the standard force gauge over time, and calculate the compensation coefficient of the sensitivity compensation curve over time.

[0056] Step 6: Calculate the compensated standard force value based on the compensation coefficient.

[0057] The specific operation of step 6 is as follows: obtain the time difference Δt between the standard force measuring instrument moving from the placement point to the measurement point, obtain the compensation coefficient based on the time difference Δt and the curve of sensitivity compensation over time, and calculate the compensated standard force value based on the compensation coefficient.

[0058] The specific steps for calculating the compensated standard force value are as follows:

[0059] F = F i (1+k)

[0060] Where F represents the compensated standard force value; F i The value represents the standard value of the standard force gauge during compensation; k represents the compensation coefficient.

[0061] Working Principle: This embodiment ensures the stability of the output voltage ratio by constructing a voltage divider network before measurement. It also calculates the compensation coefficient based on the sensitivity-time compensation curve of the standard force gauge, achieving accurate compensation of the standard force gauge under specific temperature conditions. By monitoring ambient temperature and time in real time, and adjusting the standard force gauge output according to changes and the correction curve, the system error is corrected, ensuring that the superimposed force standard machine still outputs accurate and reliable data even with temperature deviations.

[0062] Example 2:

[0063] This embodiment is based on the above embodiment 1, such as... Figure 1 As shown, the example of setting up 4 voltage divider units will be used for illustration.

[0064] This embodiment proposes a resistor voltage divider network to ensure a stable output voltage ratio. A schematic diagram of the resistor voltage divider network is shown below. Figure 1 As shown, a voltage divider circuit has multiple resistors connected in series. Except for the first and last two resistors R1 and R2, each resistor R0 in the middle is connected in parallel with n resistors R0.

[0065] Using the 0V mark as the dividing line, the number of resistors in the two rows paired above and below, i.e., the value of n, should be equal. It is recommended that the number of all parallel resistors be the same, that is, the value of n is unique for the entire network.

[0066] All these resistors should be selected from the same model, batch, resistance value, and temperature coefficient to ensure that their temperature performance is strictly the same.

[0067] The compensation method for a standard force gauge under a temperature gradient provided in this embodiment is based on the aforementioned resistive voltage divider network and includes the following steps:

[0068] Step 1: To ensure a stable output voltage ratio, a resistor divider network needs to be constructed. The circuit is built in both the horizontal (parallel) and vertical (series) directions to form the resistor divider network, as shown below. Figure 1 As shown. Divided into two levels: 50% and 100%. For example, 50% is: Therefore, simply changing the number of R0 values ​​alters the proportionality coefficient, resulting in a resistive proportional voltage divider. Resistive proportional voltage dividers are insensitive to voltage and temperature fluctuations, forming the basis for subsequent compensation methods under a given temperature gradient.

[0069] Step 2: After using a resistor divider network, voltage fluctuations will not affect the voltage ratio. By adjusting the resistor network at different ratios, a set of resistor divider coefficients corresponding one-to-one with the resistor network percentages can be obtained. These coefficients can be used to adjust the amount of data acquired by the AD chip during segmented loading. Also due to the effect of the resistor divider network, the only impact of temperature changes on the standard force gauge is the change in resistance of the foil resistance wire at different temperatures. The foil resistance wire is a precision electronic device, and its feedback to finite temperature changes within a fixed time is reproducible.

[0070] Step 3: In a laboratory environment at room temperature (20±2)℃, use a static gravity force standard machine equipped with a temperature test chamber to load the standard force gauge up to its rated load. Collect the sensitivity change of the standard force gauge every 5 minutes until the sensitivity no longer changes. Plot the sensitivity change over time curve a. When performing this step, the accuracy of the static gravity force standard machine must be more than 3 times that of the standard force gauge, and the temperature test chamber should have a control accuracy of (20±1)℃.

[0071] Step 4: Adjust the temperature of the temperature test chamber to 30℃, quickly place the standard force gauge inside and load it to its rated load, and collect the sensitivity change of the standard force gauge every 5 minutes. Continue until the sensitivity of the standard force gauge no longer changes. Plot the sensitivity change over time curve b.

[0072] Step 5: Compare curves a and b from steps 3 and 4, and calculate the different sensitivities θ of the two curves at the same time point according to the formula. Calculations were performed to obtain the time t at the same moment. i The sensitivity change rate of a standard force gauge under rated load was compared between 30℃ and 20℃. The value of k was determined based on different intervals and settling times. i There can be n values. Let k... i Using the value as the vertical axis and Δt as the horizontal axis, the n k values ​​are obtained by using the least squares method. i The values ​​are fitted into a curve, which is the standard force gauge sensitivity correction curve over time at an on-site temperature of 30℃.

[0073] Step 6: Repeat steps 4 and 5 to measure the sensitivity change rate and time curve of the standard force gauge at three temperature ranges: 20℃ to 40℃, 20℃ to 50℃, and 20℃ to 10℃. The selection of the humidity gradient depends on the temperature performance of the standard force gauge and the accuracy requirements of the sensor under test. The maximum temperature range is determined based on the temperature of the production site and is not limited to the four temperature ranges mentioned above. If necessary, the temperature range can be narrowed down, and it is not limited to 10℃ intervals.

[0074] Step 7: When not in use, the superimposed force standard machine should be stored in an environment of (20±2)℃. Before taking the superimposed force standard machine to the production site, the temperature of the site should be measured in time, and the sensitivity change ratio-time curve k should be selected according to the temperature. The time difference Δt between the superimposed force standard machine's arrival at the production site and its actual start of operation should be recorded using a time recording device. The corresponding correction coefficient k can be found on the sensitivity change-time curve using Δt, and the standard force value should be corrected during measurement. The standard force value correction formula is: F = F i (1+k), where: F represents the corrected force value; F i The force value represents the force of the standard machine during calibration, and k represents the correction factor.

[0075] Working Principle: This embodiment provides a compensation method for the standard force gauge of a superimposed force standard machine under a certain temperature gradient, enabling the superimposed force standard machine to maintain accurate measurement capabilities unaffected by significant temperature fluctuations in the production environment without altering the internal structure of its matching standard force gauge. In step 1, a resistor voltage divider network is proposed, which ensures that the voltage and resistance values ​​acquired by the AD chip are unaffected by the environment. When the temperature characteristics of multiple resistors are approximately consistent, the voltage division ratio will only depend on the number of resistors, eliminating interference from the production environment on the measurement excitation end. In steps 2-7, a method for compensating for temperature fluctuations in the foil resistance wire under stable voltage conditions is proposed. In step 3, under standard environmental conditions (20℃±2℃), the sensitivity change curve (a) of the standard force gauge at its rated load is plotted at 5-minute intervals. Since the static gravity force standard machine uses the gravity of a physical weight as the reference force value standard, its influence from ambient temperature can be considered minimal. In step 4, under environmental conditions of 30℃±1℃, the sensitivity change curve (b) of the standard force gauge at its rated load is plotted at 5-minute intervals. In step 5, comparing curves a and b from steps 3 and 4, using the θ value curve obtained in step 3 under standard conditions as the benchmark, the percentage change k of the sensitivity of curve b compared to curve a is calculated using a formula at fixed time intervals Δt, until the sensitivity of both curves under rated load is constant. The k value is then fitted to a curve according to the time interval Δt, resulting in the sensitivity compensation curve of the superimposed force standard machine (standard force gauge) over time at 30℃. In step 6, steps 4 and 5 are repeated three times to obtain three sensitivity compensation curves over time for temperatures ranging from 20℃ to 40℃, from 20℃ to 50℃, and from 20℃ to 10℃. Step 7 provides the method for using the compensation curve: first, select a suitable curve by measuring the ambient temperature; then, record the time difference Δt between the superimposed force standard machine leaving the laboratory environment and starting measurement at the production site; find the corresponding k value on the curve; and use the formula to perform temperature compensation during the measurement process. If the measurement process lasts for a long time, the time difference Δt can be continuously recorded, and the curve can be used to compensate for the measured value in real time. In the above steps, step 1 stabilizes the on-site voltage environment; steps 2-4 plot the sensitivity curves of the standard force gauge of the superimposed force standard machine under standard and specific temperature gradients; step 5 provides the calculation method for the time compensation curve; step 6 explains the scalability in the temperature dimension; and step 7 provides the compensation method, ultimately ensuring the accurate compensation of the superimposed force standard machine under specific temperature conditions. All steps in this embodiment can be repeatedly verified, and the adaptability of the superimposed force standard machine to specific production sites deviating from the standard temperature can be achieved by adjusting the acquisition time interval and setting different temperature ranges. The compensation curve data is based on repeated acquisitions from multiple experiments, ensuring data accuracy and reliable conclusions.

[0076] The advantage of this embodiment is that it provides a reliable, time-dependent, and repeatable compensation method for superimposed force standard machines applied to production sites where the temperature deviates from the standard environment, ensuring the accuracy and reliability of the output data of the superimposed force standard machine in production sites with temperature deviations.

[0077] The other parts of this embodiment are the same as those in Embodiment 1 above, so they will not be described again.

[0078] Example 3:

[0079] This embodiment is based on any one of embodiments 1-2 above, and will be described in detail with a specific example. A total of 6 resistors are set in the series direction. Except for the two resistors at the front and back of the queue, the remaining 4 resistors are each connected in parallel with 10 resistors. These parallel resistors are also interconnected in the series direction, forming a 4*10=40 resistor voltage divider network.

[0080] like Figure 1 As shown, from top to bottom, the voltage point between the 3rd and 4th resistors is 0V.

[0081] The voltage difference between the third and fourth resistors is ΔU when the voltage divider network is at 50% of its range, while the voltage difference between the second and third resistors and the fourth and fifth resistors is ΔU when the voltage divider network is at 100% of its range.

[0082] How can voltage ratio measurement be applied to a Wheatstone bridge to measure minute resistance changes, such as... Figure 2 As shown:

[0083] A typical Wheatstone bridge is as follows: Figure 2 As shown, this is a symmetrical rhomboid structure with four bridge arms, containing three resistors with known resistance values ​​R3, R4, and R5, and one resistor with a variable resistance value R. x '. R when the standard force gauge elastomer is not under load x =R3, when it bears a load R x =R3+ΔR.

[0084] For ease of understanding, Figure 2 The circuit in can be redesigned as Figure 3 With four resistors set unchanged, and the excitation voltage of the entire bridge circuit being U, the current flowing through R5 after the bridge voltage divider is... Flow through R x 'current Then there is a voltage across resistor R5 resistor R x Voltage on but Figure 3The voltage across resistor R5 is the potential difference between points a and b.

[0085]

[0086] Furthermore, there are

[0087] In practical applications, the bridge arm resistors can be designed as R3 = R4 = R5 = R x If -ΔR = R, then the equation in the previous step can be simplified to: Since the micro-resistance strain ΔR represents the deformation of the foil resistance wire inside the standard force gauge and is a parameter that needs to be determined, ΔR needs to be placed on the left side of the equation, and the above equation can be transformed into: Right now

[0088] Transformed into Right now

[0089] From the above equation, we can see that the variable bridge arm resistance R x The micro-resistance change ΔR caused by load deformation is only related to R and Two parameters are related: the bridge arm resistance value R can be fixed by selecting appropriate components, while the voltage ratio... The proportional correction can be achieved through a resistor voltage divider network, avoiding errors caused by environmental fluctuations when measuring U and ΔU on the production site.

[0090] A compensation method for a standard force gauge under a temperature gradient includes the following steps:

[0091] Step 1: Select a temperature chamber environment of (20±1)℃ and use a 0.01 grade static gravity force standard machine to measure the 0.03 grade standard force gauge. After the load is applied to the rated load of 20kN of the standard force gauge, the sensitivity change of the standard force gauge is collected every 5 minutes. After 30 minutes, the sensitivity of the standard force gauge no longer changes.

[0092] Step 2: Adjust the temperature chamber to 30℃, quickly place the standard force gauge inside and reload it to 20kN. Collect the sensitivity change of the standard force gauge every 5 minutes. After 40 minutes, the sensitivity of the standard force gauge no longer changes.

[0093] Step 3: Compare curves a and b from Step 1 and Step 2, and calculate the different sensitivities θ of the two curves at the same time point according to the formula. Calculations were performed to obtain the time t at the same moment. i The sensitivity change rate of a standard force gauge under rated load is compared between 30℃ and 20℃. In this application example, k i There are a total of 9 values. Let k... iUsing the value as the vertical axis and Δt as the horizontal axis, the nine k values ​​obtained are calculated using the least squares method. i The values ​​are fitted into a curve, which is the standard force gauge sensitivity correction curve over time at an on-site temperature of 30℃.

[0094] Step 4: Take the superimposed force standard machine to the production site at 30℃ for measurement. Record the time interval between the superimposed force standard machine leaving the laboratory environment and being adjusted and ready for measurement at the production site, which is a total of 15 minutes. At this time, refer to the curve drawn in step S3) to obtain k when Δt = 15. i The nominal value of the first measurement point is 2kN, and the displayed value is 2.0017kN. Therefore, the actual value should be 2.0017*(1+k). When the second measurement point begins, 2 minutes have passed. At this time, the k value at Δt=17 should be obtained from the curve. i The new k value is then used to correct the data at the second measurement point. This process is repeated for the remaining measurement points.

[0095] The other parts of this embodiment are the same as any one of the embodiments 1-2 above, so they will not be described again.

[0096] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A compensation method for a standard force gauge under a temperature gradient, wherein the standard force gauge comprises a temperature test chamber and a foil resistance wire for measuring micro-resistance changes, characterized in that, The compensation method specifically includes the following steps: Step 1: Construct a resistance voltage divider network on the variable bridge arm of the foil resistance wire of the standard force gauge, and adjust the micro resistance change of the variable bridge arm. Step 2: Set the temperature test chamber to room temperature, use the temperature test chamber to load the standard force gauge to the rated load, collect the change in sensitivity of the standard force gauge within a set time interval until the change in sensitivity remains constant, and plot the curve a of sensitivity change over time. Step 3: Set the temperature test chamber to the set temperature, load the standard force gauge to the rated load, collect the change in sensitivity of the standard force gauge within the set time interval until the change in sensitivity remains constant, and plot the curve b of sensitivity change over time. Step 4: Calculate the rate of change of sensitivity at the same time point based on curve a and curve b; Step 5: Using the sensitivity change rate as the vertical axis and the set time interval as the horizontal axis, obtain the sensitivity compensation curve of the standard force measuring instrument over time, and calculate the compensation coefficient of the sensitivity compensation curve over time. Step 6: Calculate the compensated standard force value based on the compensation coefficient; The specific steps for calculating the rate of change of sensitivity at the same time point in step 4 are as follows: ； in, For t i Sensitivity at time b under curve b For t i Sensitivity at time a under curve a, k i The rate of change of sensitivity; The specific operation of step 6 is as follows: obtain the time difference Δt between the standard force measuring instrument moving from the placement point to the measurement point, obtain the compensation coefficient based on the time difference Δt and the curve of sensitivity compensation over time, and calculate the compensated standard force value based on the compensation coefficient. The specific steps for calculating the compensated standard force value are as follows: ； in, This represents the standard force value after compensation; The standard value of the standard force gauge during compensation; This represents the compensation coefficient.

2. The compensation method for a standard force gauge under a temperature gradient according to claim 1, characterized in that, The resistor voltage divider network constructed in step 1 includes a positive input unit, a voltage divider unit, and a negative input unit; The input terminal of the positive input unit is connected to the positive terminal of the power supply, and the output terminal is connected to the input terminal of the voltage divider unit. The input terminal of the negative input unit is connected to the negative terminal of the power supply, and the output terminal is connected to the input terminal of the voltage divider unit. The positive input unit includes a resistor R1; the negative input unit includes a resistor R2; the voltage divider unit includes N voltage divider units, where N is an even number greater than or equal to 2; Each of the N voltage divider units includes n resistors R0 connected in parallel; The resistance values ​​and temperature coefficients of resistors R1, R2, and R0 are all the same.

3. The compensation method for a standard force gauge under a temperature gradient according to claim 2, characterized in that, The specific operation of adjusting the micro-resistance change of the variable bridge arm in step 1 is as follows: based on the constructed resistor voltage divider network and the number N of the voltage divider units, the output voltage is divided into N / 2 levels, and the micro-resistance change of the variable bridge arm is adjusted by adjusting the number of resistors R0 in the voltage divider units.

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