Temperature detection method and system based on overturning displacement of bimetallic strip

Abstract

The invention relates to the technical field of bimetallic deformation temperature detection, in particular to a temperature detection method and system based on bimetallic strip overturning displacement, and the method comprises the steps: setting one end of a bimetallic strip as a fixed end, setting the end away from the fixed end as a detection end, enabling the fixed end to be installed on a limiting tool, and enabling the detection end to be an overturning displacement end with temperature change; the temperature detection environment is subjected to thermal cycle from the initial temperature T0 to the limiting temperature Ta, Tagt; t0; setting a temperature detection threshold Tb and Tagt; tbgt; Tbgt; the deviation position corresponding to the fact that the detection end reaches the temperature detection threshold value Tb in the temperature detection environment thermal cycle is collected; parameters in the temperature detection environment are controlled, and corresponding detection information is obtained; and judging the temperature accuracy of the overturning displacement of the bimetallic strip according to the detection information. According to the invention, the technical problem of dynamic misalignment of the displacement measurement value and the actual temperature caused by the temperature change rate difference of the bimetallic strip under the asymmetric thermal cycle working condition is effectively solved.

Description

Technical Field

[0001] This invention relates to the field of bimetallic deformation temperature detection technology, and in particular to a temperature detection method and system based on the flip displacement of a bimetallic sheet. Background Technology

[0002] As a core component of mechanical temperature control devices, bimetallic strip temperature sensors work on the principle that the difference in thermal expansion coefficients of the different metal layers causes directional deformation when the temperature changes. This deformation drives the moving end to displace, triggering a switch action. By measuring the displacement of the bimetallic strip, the temperature change can be indirectly determined. In fields involving precise detection of critical temperatures, such as overheat protection of power equipment and industrial temperature control systems, accurately obtaining the flip displacement of the bimetallic strip is crucial for achieving accurate temperature detection.

[0003] In practical applications, bimetallic strips suffer from deviations during thermal cycling, especially when the rate of temperature change is uneven or the temperature environment changes drastically. The bimetallic strip's response often fails to keep pace with the actual temperature change. This unstable thermal cycling process leads to a deviation in the relationship between the bimetallic strip's displacement and temperature, thereby affecting the accuracy of temperature measurement.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the general background of this disclosure and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] This invention provides a temperature detection method and system based on the flip displacement of a bimetallic strip, which can effectively solve the problems in the background art.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A temperature detection method based on bimetallic strip flip displacement, the method comprising: One end of the bimetallic strip is set as a fixed end, and the end away from the fixed end is set as a detection end. The fixed end is installed on a limiting fixture, and the detection end is a flip-displacement end that changes with temperature. The bimetallic strip is placed in a temperature detection environment, which ranges from an initial temperature T0 to a limiting temperature T. a Thermal cycling occurs between them, and the T a >T0; Set temperature detection threshold T b And the T a >T b >T0, and collect the temperature detection threshold T reached by the detection end during the thermal cycle of the temperature detection environment. b The corresponding offset position; The parameters in the temperature detection environment are controlled, including at least the heating rate, cooling rate, and extreme temperature, to obtain the corresponding detection information; The temperature accuracy of the bimetallic strip's flip-off displacement is determined based on the detection information.

[0007] Further, placing the bimetallic strip in a temperature detection environment includes: The bimetallic strip is designed with a specific geometry that satisfies the requirements for abrupt displacement detection and gradual displacement detection at the detection end under temperature change conditions. The bimetallic strip is placed against a controllable heat source, causing the detection end to rise from an initial temperature T0 to a limiting temperature T. a Temperature changes that are either linearly accelerated or uniformly accelerated; The detection terminals collect data at the temperature detection threshold T. b The initial temperature T0 to the extreme temperature T a Location information and corresponding time points between them.

[0008] Furthermore, it also includes: The initial temperature T0 is increased to the extreme temperature T. a The corresponding positional distances between them are divided into equal parts, and at least into three equal parts, with each division point being a continuous detection point; An optical interruption triggering device is provided on the bimetallic strip flipping displacement path, including the temperature detection threshold T. b The corresponding flip displacement and the continuous detection points; When the detection end flips and shifts to the temperature detection threshold T b At the location and the continuous detection points, the optical path is blocked and the corresponding time nodes are collected synchronously.

[0009] Furthermore, the thermal cycle is set to raise the initial temperature T0 to the limiting temperature T. a To accelerate the heating process and with a required time of T1, the limiting temperature T a The temperature drops to the initial temperature T0 at a uniform rate, and the time required is T2, wherein T1... T2.

[0010] Furthermore, the accuracy of temperature is judged based on the detection information, including: The temperature detection threshold T is obtained when the detection end reaches the specified temperature during multiple thermal cycles. b The historical set of offset positions; The historical set of offset positions is arranged in a time series on a two-dimensional plane to generate a cumulative displacement trajectory map; The linear drift state or nonlinear abrupt change state within the cycle of the thermal cycle is identified based on the cumulative displacement trajectory diagram. The durability degradation level of the bimetallic strip's temperature response accuracy is determined based on the linear drift state or the non-linear abrupt change state. The durability degradation level is used to quantitatively evaluate the degree of performance degradation of the bimetallic strip under the thermal cycling.

[0011] Further, the durability degradation level is determined, including: A parameter group consisting of the heating rate and the cooling rate in the temperature detection environment is associated with the control. Obtain the differences in the distribution characteristics of the historical set of offset positions under different heating and cooling rates; Based on the differences in distribution characteristics, a hysteresis correlation model is established to determine the dynamic response relationship between the displacement deviation of the bimetallic sheet and the temperature change rate of the thermal cycle. The threshold for determining the durability degradation level is corrected based on the displacement reference compensation amount output by the hysteresis correlation model.

[0012] Furthermore, if the displacement change state is the linear drift state, the displacement reference compensation amount is added to all the determination thresholds of the durability degradation level; if it is the nonlinear abrupt change state, the absolute value of the displacement reference compensation amount is subtracted from the failure level determination threshold of the durability degradation level.

[0013] Furthermore, a lag correlation model is established, including: The historical set of offset positions corresponding to each group of heating rate and cooling rate is decomposed into thermal expansion displacement data sequence of temperature rising interval and cold contraction displacement data sequence of temperature falling interval. In the thermal expansion displacement data sequence, the temperature detection threshold T b A set of thermal expansion response slopes is obtained by dividing the data into segments based on reference points and performing multi-segment linear fitting. The same reference point division method is used to obtain the set of cold contraction response slopes in the cold contraction displacement data sequence. For the same temperature change range, the slope values ​​of the thermal expansion response slope set and the slope values ​​of the cold contraction response slope set are obtained, and the absolute difference value is calculated. The absolute difference values ​​of all ranges are collected to form a hysteresis feature dataset. Using the heating rate and the cooling rate as independent variables and the hysteresis feature dataset as the dependent variable, an analytical expression for the dynamic response relationship is generated based on the least squares fitting method, which serves as the hysteresis correlation model.

[0014] A temperature detection system based on bimetallic strip flip displacement, the system comprising: The tooling fixing module has one end of the bimetallic strip set as the fixed end and the end away from the fixed end set as the detection end. The fixed end is installed on the limit tooling, and the detection end is the flip displacement end that is affected by temperature changes. The temperature cycling module places the bimetallic strip in a temperature detection environment, which ranges from an initial temperature T0 to a limiting temperature T. a Thermal cycling occurs between them, T a >T0; Offset detection module, set temperature detection threshold T b And T a >T b >T0, and collect the temperature detection threshold T reached by the detection end during the thermal cycle of the temperature detection environment. b The corresponding offset position; The parameter control module controls the parameters in the temperature detection environment, including at least the heating rate, cooling rate, and extreme temperature, and obtains the corresponding detection information. The accuracy detection module determines the temperature accuracy of the bimetallic strip's flip displacement based on the detection information.

[0015] Furthermore, the accuracy detection module includes: The historical information unit acquires the temperature detection threshold T reached by the detection end during multiple thermal cycles. b The historical set of offset positions; The image generation unit arranges the historical set of offset positions in a time series on a two-dimensional plane to generate a cumulative displacement trajectory map. The state recognition unit identifies the linear drift state or nonlinear abrupt change state within the cycle of thermal cycling based on the cumulative displacement trajectory diagram. The attenuation determination unit determines the durability attenuation level of the bimetallic strip's temperature response accuracy based on linear drift or nonlinear abrupt change. The durability attenuation level is used to quantitatively assess the degree of performance degradation of the bimetallic strip under thermal cycling.

[0016] The technical solution of this invention can achieve the following technical effects: By constructing a mathematical quantification model of the difference in response slope between displacement and temperature curves during expansion or contraction, and dynamically correcting the judgment threshold based on the temperature change rate parameter, real-time compensation for thermal cycling displacement drift, which is impossible to achieve with traditional static detection methods, is realized. This solves the technical problem of dynamic inaccuracy between displacement measurement and actual temperature caused by thermal hysteresis accumulation due to the difference in temperature change rate under asymmetric thermal cycling conditions of bimetallic sheets.

[0017] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart illustrating a temperature detection method based on bimetallic strip flipping displacement. Figure 2 A flowchart illustrating the process for determining temperature accuracy; Figure 3 A flowchart illustrating the process for determining the durability degradation level; Figure 4 This is a schematic diagram of the compensation process for changes in displacement and state. Figure 5 A flowchart illustrating the process of establishing a lag correlation model. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0022] Example 1; like Figure 1 As shown, this application provides a temperature detection method based on the flip displacement of a bimetallic strip, the method comprising: One end of the bimetallic strip is set as the fixed end, and the end away from the fixed end is set as the detection end. The fixed end is installed on the limiting fixture, and the detection end is the flipping displacement end that changes with temperature. The bimetallic strip is placed in a temperature detection environment, which ranges from an initial temperature T0 to a limiting temperature T. a Thermal cycling occurs between them, T a >T0; Set temperature detection threshold T b And T a >T b >T0, and collect the temperature detection threshold T reached by the detection end during the thermal cycle of the temperature detection environment. b The corresponding offset position; Control the parameters in the temperature detection environment, including at least the heating rate, cooling rate, and extreme temperature, and obtain the corresponding detection information; The accuracy of the temperature of the bimetallic strip's flip-off displacement is judged based on the detection information.

[0023] Specifically, one end of the bimetallic strip is fixed by fasteners and mounted on a bracket with a limiting fixture, while the other end serves as the detection end. The bimetallic strip material is preferably copper-steel or another combination of materials with a significant difference in thermal expansion coefficients and good machinability; the thickness and width are selected according to the required sensitivity. The temperature detection environment is cycled multiple times from an initial temperature to a limiting temperature; a preferred example is an initial temperature of 20 degrees Celsius and a limiting temperature of 120 degrees Celsius to cover the typical operating range. The temperature detection threshold T... b At T0 and T a The points between these points are set and recorded as judgment points; displacement measurement uses an optical interruption device to obtain the detection end when the temperature reaches the threshold T. b The offset position at time is recorded and the timestamp is recorded. Simultaneously, data from the temperature sensor and displacement sensor are synchronously recorded through a unified data acquisition system for subsequent correlation analysis. During the thermal cycling process, parameters of the temperature control environment are controlled and studied as variable parameters, including at least the heating rate, cooling rate, and extreme temperature T. a For example, multiple sets of experiments can be conducted with heating rates of 0.5, 2, and 10 degrees Celsius per minute to observe the effect of the rate on the trigger temperature of the flip-over displacement. The cooling rate can be similarly grouped, with the limiting temperature T... a Multiple values ​​can be taken within the range of 80 to 150 degrees Celsius to examine nonlinear behavior; in each experiment, the temperature at the detection end is recorded and extracted in ascending or descending order by setting a temperature threshold T. b The instantaneous offset position, corresponding temperature value, and time are determined by repeating the experiment at least five times for each set of conditions to obtain statistical data. The mean, standard deviation, and drift are calculated, and filtering and noise reduction processes are employed, such as low-pass filtering and moving average, to improve signal reliability. Simultaneously, a preprocessing cycle is performed to eliminate the initial stress relaxation effect of the material. Furthermore, analysis of the parameter influence reveals that larger heating and cooling rates cause temperature lag and measurement offset, with the extreme temperature T... a The residual stress and cyclic stability of the material are affected. It is preferable to perform multiple cycles before formal measurement to stabilize the performance and record the drift trend. Based on the effective detection information obtained above, the temperature accuracy of the bimetallic strip flip displacement can be judged.

[0024] The technical solution of this invention constructs a mathematical quantification model of the difference in response slope between displacement and temperature curves during expansion or contraction, and dynamically corrects the judgment threshold based on the temperature change rate parameter. This achieves real-time compensation for thermal cycling displacement drift, which is impossible to achieve with traditional static detection methods. It solves the technical problem that thermal hysteresis accumulation caused by the difference in temperature change rate under asymmetric thermal cycling conditions of bimetallic sheets leads to dynamic inaccuracy between displacement measurement values ​​and actual temperature.

[0025] Furthermore, placing the bimetallic strip in a temperature detection environment includes: Design a specific geometry for the bimetallic strip, which satisfies the requirements for abrupt and gradual displacement detection at the detection end under temperature change conditions; The bimetallic strip is placed against a controllable heat source, causing the detection end to rise from the initial temperature T0 to the extreme temperature T. a Temperature changes that are either linearly accelerated or uniformly accelerated; The acquisition and detection terminals are respectively at the temperature detection threshold T b From initial temperature T0 to extreme temperature T a Location information and corresponding time points between them.

[0026] As a preferred embodiment of the above, the bimetallic strip is preferably designed with a geometric combination that enables both abrupt displacement (instantaneous flipping) and gradual displacement (continuous bending) responses. This allows for the detection of both the critical trigger temperature and displacement over the entire temperature range on the same sample. Regarding the heat source arrangement and temperature control, the bimetallic strip is preferably placed against a controllable heat source. The heat source contacts the sample through a flat contact surface to reduce contact thermal resistance, thereby enabling two types of temperature change modes: one is a constant temperature change rate, such as a commonly used rate of 0.5, 2, or 10 degrees Celsius per minute; the other is a linearly accelerated heating rate, i.e., a heating rate that increases linearly with time, for example, an initial rate of 0.5 degrees Celsius per minute, linearly accelerated to 5 degrees Celsius per minute. Except for the acquisition and detection end at the preset temperature detection threshold T... b In addition to the location information, it is also necessary to continuously record the temperature from the initial temperature T0 to the extreme temperature T. a The displacement between them changes with temperature and time, so as to extract T under different heating conditions. b The displacement value and trigger time at the point can also be used to analyze the gradual response and hysteresis characteristics of the entire temperature range. To ensure data reliability, it is preferable to perform several pre-treatment thermal cycles before formal testing to stabilize material properties, and repeat the test at least three to five times under each set of experimental conditions to obtain statistical distribution. At the same time, abrupt change detection is performed on the original displacement data to identify abrupt change points.

[0027] Furthermore, it also includes: From the initial temperature T0 to the extreme temperature T aThe corresponding positional distances between them are divided into equal parts, and at least into three equal parts, with each division point being a continuous detection point; An optical interruption triggering device is installed on the bimetallic strip flipping displacement path, including a temperature detection threshold T. b The corresponding flip displacement and continuous detection points; When the detection end flips and shifts to the temperature detection threshold T b At the point of origin and at continuous detection points, the optical path is blocked and the corresponding time nodes are collected simultaneously.

[0028] As a preferred embodiment of the above, the temperature range of the bimetallic strip from the initial temperature T0 to the limiting temperature T is first determined. a The corresponding total travel of the detection end is divided into at least three equal parts according to the principle of equal division. Preferably, the division points are used as continuous detection points, and optical triggering devices are arranged at these points. If the travel is divided into N equal parts, then a continuous detection point is set at each of the N-1 internal division positions, T b The corresponding flip displacement point is also set separately in the optical trigger array or coincides with a certain equally spaced point; preferably, a photoelectric switch that works by blocking the optical path is selected; regarding synchronous acquisition and timestamp, it is preferable to connect the switching signals of all optical trigger devices in parallel to a data acquisition unit or real-time controller with high-resolution timestamp function, when the detection end moves to any continuous detection point or T b When the optical path is blocked, the change in the output level of the trigger device is immediately captured by the data acquisition system and the time node and corresponding trigger channel are recorded under the same time reference, thereby obtaining the time of occurrence of each equally divided point; finally, for example: if the detection end of a preferred experimental sample changes from T0 to T... a If the measurable displacement is 3 mm, then divide this 3 mm into three equal segments, install optical interruption triggering devices at 1 mm and 2 mm respectively, and at T... b A high-sensitivity reflective optical sensor is installed at the corresponding 1.8 mm position. During the experiment, when the detection end passes through the 1 mm, 1.8 mm and 2 mm positions in sequence, the time nodes and triggering sequence recorded by the corresponding channels under the same time reference can be used to accurately calibrate the correspondence between displacement and temperature and identify instantaneous flip events and gradual passing events.

[0029] Furthermore, the thermal cycle is set to raise the initial temperature T0 to the limiting temperature T. a To accelerate heating and with a required time of T1, the limiting temperature T a The temperature drops to the initial temperature T0 at a constant rate, and the time required is T2 and T1. T2.

[0030] As a preferred embodiment of the above, the thermal cycling process is precisely controlled in segments for accelerated heating and uniform cooling. Specifically, during the heating phase, a preset accelerated temperature curve or segmented power output is used to rapidly increase the temperature from the initial temperature T0 to the limit temperature T within time T1. a During the cooling phase, the same temperature control system or an independent cooling device lowers the temperature from T to T at a constant rate within time T2. a The temperature is reduced at a constant rate back to T0. In terms of process, the instantaneous flipping and displacement behavior of the detection end should be observed and recorded during the accelerated heating phase to verify the impact of accelerated heating on the trigger temperature and triggering mechanism. The uniform cooling phase is used to obtain repeatable return characteristics and hysteresis data.

[0031] Furthermore, such as Figure 2 As shown, the accuracy of temperature is judged based on the detection information, including: The detection end reaches the temperature detection threshold T during multiple thermal cycles. b The historical set of offset positions; Arrange the historical set of offset positions in a time series on a two-dimensional plane to generate a cumulative displacement trajectory map; Identify linear drift or nonlinear abrupt change states within the cycle of thermal cycling based on the cumulative displacement trajectory diagram; The durability degradation level is determined based on the linear drift state or nonlinear abrupt change state to assess the degree of performance degradation of the bimetallic strip under thermal cycling.

[0032] As a preferred embodiment of the above, firstly, during multiple thermal cycling tests, when the detection end reaches the set temperature threshold T for each thermal cycle... b Record the displacement offset values ​​at each time point and save these offset values ​​in chronological order to form a historical offset position set. Data acquisition should be synchronized with timestamp recording. Then, plot the historical offset position set as a cumulative displacement trajectory in a two-dimensional plane, where the horizontal axis represents time or the number of cycles, and the vertical axis represents time (T). bThe offset position is marked on the graph to visually represent the trend and sudden events. In the analysis of the cumulative trajectory graph, it is preferable to identify two typical states: linear drift state and nonlinear abrupt change state. For the identification of linear drift state, local linear fitting and overall trend fitting methods based on sliding windows can be used. By comparing the fitting residuals, the slope of the fitting line and the goodness of fit index, it is determined whether there is a stable linear upward or downward trend. If a consistent direction and a stable non-zero slope can be obtained in most continuous windows, it is determined to be linear drift. For the identification of nonlinear abrupt change state, abrupt change point detection method is preferred, such as cumulative sum detection, piecewise fitting and abrupt change amplitude threshold determination, or a change point based on statistical significance. When the displacement increment or abrupt change amplitude at a certain moment significantly exceeds the stationary noise level and remains at a new level or enters unstable fluctuation after the change, it is determined to be a nonlinear abrupt change event. After identifying the state, the temperature response accuracy durability of the sample is classified according to pre-set or empirical quantification rules in order to quantify the degree of degradation.

[0033] Furthermore, such as Figure 3 As shown, the determination of durability degradation level includes: A parameter set consisting of the heating rate and cooling rate in the temperature detection environment of the associated control; To obtain the differences in the distribution characteristics of the historical set of offset positions under different heating and cooling rates; A hysteresis correlation model is established based on the differences in distribution characteristics to determine the dynamic response relationship between the displacement deviation of the bimetallic strip and the temperature change rate of the thermal cycle. The threshold for determining the durability degradation level is adjusted based on the displacement benchmark compensation amount output by the hysteresis correlation model.

[0034] As a preferred embodiment of the above, the historical set of offset positions is systematically acquired and the differences in their distribution characteristics are extracted under different combinations of heating and cooling rates. Specifically, firstly, several typical heating and cooling rate values ​​are selected according to the designed parameters, such as heating rates covering several ranges from 0.5 to 20 degrees Celsius / minute and cooling rates covering several ranges from 0.5 to 10 degrees Celsius / minute. The two are then combined or stratified to form parameter groups, and multiple thermal cycling tests are conducted on each parameter group. During each cycle, the temperature threshold T at the detection end is recorded synchronously. bThe system records the displacement value and complete displacement time at the location, along with the temperature and timestamp to ensure data time alignment. Based on the above and the corresponding heating and cooling rate parameters, a dynamic response relationship model between displacement deviation and temperature change rate is established using the hysteresis correlation modeling method. The resulting hysteresis correlation model is used to calculate the displacement benchmark compensation amount under any given thermal cycle parameter set. This compensation amount characterizes the systematic deviation and hysteresis effect caused by different heating and cooling rates and should be expressed as displacement amount or equivalent temperature error. When determining the durability degradation level, the system first reads the heating rate and cooling rate parameters of the current or test to be evaluated, predicts the corresponding compensation amount through the model, and applies it to the judgment threshold. Specifically, the judgment threshold is adjusted by addition or subtraction to eliminate the deviation introduced by the rate, so that the level determination can better reflect the true fatigue and degradation state of the material and structure.

[0035] Furthermore, such as Figure 4 As shown, if the displacement change state is a linear drift state, the displacement reference compensation amount is added to all the judgment thresholds of the durability degradation level; if it is a nonlinear abrupt change state, the absolute value of the displacement reference compensation amount is subtracted from the failure level judgment threshold of the durability degradation level.

[0036] As a preferred embodiment of the above, after each batch or each test cycle, the cumulative displacement trajectory diagram is used to determine whether the current displacement change belongs to a linear drift state or a nonlinear abrupt change state. Once the state is determined, the system reads the corresponding current thermal cycle parameter set, including the heating rate and cooling rate, from the established hysteresis correlation model, and predicts the displacement baseline compensation amount. For the linear drift state, all judgment thresholds defined by the durability degradation level are added to the displacement baseline compensation amount, so that the original thresholds have fault tolerance for systematic shifts caused by rate or chronic drift after compensation, thereby avoiding misjudging long-term stable drift as acute failure. At the same time, a reasonable upper limit should be set during adjustment, not exceeding the predefined safety boundary. For the nonlinear abrupt change state, the judgment threshold used to define the failure level, i.e., the judgment threshold of the highest level judgment, is subtracted from the absolute value of the displacement baseline compensation amount, so that single or sudden large changes are more easily classified as failures to trigger maintenance or shutdown procedures. Other lower level thresholds can be retained or only slightly modified as appropriate. Preferably, a smoothing mechanism is implemented for threshold changes, such as requiring consistent judgments for several consecutive rounds or using a moving average compensation amount before updating.

[0037] Furthermore, such as Figure 5 As shown, a lag correlation model is established, including: The historical set of offset positions corresponding to each group of heating rate and cooling rate is decomposed into thermal expansion displacement data sequence of temperature rising interval and cold contraction displacement data sequence of temperature falling interval. In the thermal expansion displacement data sequence, the temperature detection threshold T is used. bThe thermal expansion response slope set is obtained by dividing the area into segments based on the reference point and performing multi-segment linear fitting. The cold contraction displacement data sequence is obtained by using the same reference point division method to obtain the cold contraction response slope set. For the same temperature change range, the slope values ​​of the thermal expansion response slope set and the slope values ​​of the cold contraction response slope set are obtained, and the absolute difference value is calculated. The absolute difference values ​​of all ranges are collected to form a hysteresis feature dataset. Using heating rate and cooling rate as independent variables and lag feature dataset as dependent variable, an analytical expression for the dynamic response relationship is generated based on the least squares fitting method as a lag correlation model.

[0038] As a preferred embodiment of the above, each parameter group, i.e., a set of historical offset positions obtained under a specific heating rate and cooling rate, is first separated cyclically and further decomposed into two time-series subsequences: one is the thermal expansion displacement data sequence corresponding to the temperature rise interval, and the other is the cold contraction displacement data sequence corresponding to the temperature fall interval. The decomposition is based on the timestamp and temperature value recorded by the temperature sensor, strictly distinguishing the temperature range from the initial temperature T0 to the extreme temperature T. a The heating phase and the T a Returning to the cooling segment at T0, preprocessing the sections with short-term temperature echoes to ensure segment continuity; then, for each cycle, increment the temperature axis by T. b Using T as a reference point, the rising and falling intervals are divided into several segments with the same temperature difference. The division method can be as follows: b Extending upwards and downwards by several temperature difference units until covering the entire T0 to T1 range. aThe interval is selected, with the number of segments preferably between 5 and 20 to balance resolution and robustness. The temperature range and corresponding displacement subset of each segment are recorded. Subsequently, multi-segment linear fitting is performed on the thermal expansion displacement subset and the cold contraction displacement subset within each segment. The fitting object is the linear relationship between displacement and temperature or time. Using temperature as the independent variable can more intuitively reflect the thermal response. The local response slope is output during fitting. This yields the thermal expansion response slope set and the cold contraction response slope set. Each pair of slopes in the two sets corresponds to the same temperature change segment. The absolute difference between the thermal expansion slope and the cold contraction slope is calculated for each corresponding segment, and the absolute difference values ​​of all segments are collected to form the hysteresis feature dataset under this parameter set. To establish a hysteresis correlation model, the heating rate and cooling rate are used as independent variables, and the above hysteresis feature dataset is used as the dependent variable. The least squares fitting regression modeling process is used to generate the dynamic response relationship. The analytical expression is as follows: During model building, it is first determined whether the independent variables need to be introduced into the model as interaction terms or higher-order terms to describe the nonlinear coupling effect. If there is multicollinearity or model complexity issues, regularization techniques can be introduced to stabilize the fit. For example, in a set of experiments, heating rates of 0.5, 2, and 10 degrees Celsius / minute and cooling rates of 0.5, 2, and 5 degrees Celsius / minute are selected. For each rate combination, at least 10 cycles are performed and the model is divided into 10 temperature difference segments. The heating slope and cooling slope of each segment are fitted separately, and their absolute differences are calculated to form a lag feature vector. Then, the mean of the absolute difference of each segment is used as the dependent variable for least squares regression. Finally, an analytical expression reflecting the influence of heating and cooling rates on lag differences is obtained, and the fitting accuracy is obtained in the validation set. This analytical expression is the lag correlation model, which can be used to predict displacement deviations under new parameter sets and as a basis for compensation.

[0039] Example 2; Based on the same inventive concept as the temperature detection method based on bimetallic strip flip-off displacement in the foregoing embodiments, the present invention also provides a temperature detection system based on bimetallic strip flip-off displacement, the system comprising: The tooling fixing module has one end of the bimetallic strip set as the fixed end and the end away from the fixed end set as the detection end. The fixed end is installed on the limit tooling, and the detection end is the flip displacement end that is affected by temperature changes. The temperature cycling module places the bimetallic strip in a temperature detection environment, which ranges from an initial temperature T0 to a limiting temperature T. a Thermal cycling occurs between them, T a >T0; Offset detection module, set temperature detection threshold T b And T a >T b >T0, and collect the temperature detection threshold T reached by the detection end during the thermal cycle of the temperature detection environment. b The corresponding offset position; The parameter control module controls the parameters in the temperature detection environment, including at least the heating rate, cooling rate, and extreme temperature, and obtains the corresponding detection information. The accuracy detection module determines the temperature accuracy of the bimetallic strip's flip displacement based on the detection information.

[0040] The adjustment system described above in this invention can effectively realize the temperature detection method based on the bimetallic strip flipping displacement, and the technical effects it can achieve are as described in the above embodiments, and will not be repeated here.

[0041] Furthermore, the accuracy detection module includes: The historical information unit acquires the temperature detection threshold T reached by the detection end during multiple thermal cycles. b The historical set of offset positions; The image generation unit arranges the historical set of offset positions in a time series on a two-dimensional plane to generate a cumulative displacement trajectory map. The state recognition unit identifies the linear drift state or nonlinear abrupt change state within the cycle of thermal cycling based on the cumulative displacement trajectory diagram. The attenuation determination unit determines the durability attenuation level of the bimetallic strip's temperature response accuracy based on linear drift or nonlinear abrupt change. The durability attenuation level is used to quantitatively assess the degree of performance degradation of the bimetallic strip under thermal cycling.

[0042] Similarly, the above-mentioned optimization schemes for the system can also achieve the optimization effects corresponding to the methods in Embodiment 1, which will not be repeated here.

[0043] Although this application has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of this application. Accordingly, this specification and drawings are merely exemplary illustrations of the application as defined herein, and are to be considered as covering any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Thus, if such modifications and modifications fall within the scope of this application and its equivalents, this application intends to include such modifications and modifications.

Claims

1. A temperature detection method based on bimetallic strip flip displacement, characterized in that, The method includes: One end of the bimetallic strip is set as a fixed end, and the end away from the fixed end is set as a detection end. The fixed end is installed on a limiting fixture, and the detection end is a flip-displacement end that changes with temperature. The bimetallic strip is placed in a temperature detection environment, which ranges from an initial temperature T0 to a limiting temperature T. a Thermal cycling occurs between them, and the T a >T0; Set temperature detection threshold T b And the T a >T b >T0, and collect the temperature detection threshold T reached by the detection end during the thermal cycle of the temperature detection environment. b The corresponding offset position; The parameters in the temperature detection environment are controlled, including at least the heating rate, cooling rate, and extreme temperature, to obtain the corresponding detection information; The temperature accuracy of the bimetallic strip's flip-off displacement is determined based on the detection information.

2. The temperature detection method based on bimetallic strip flipping displacement according to claim 1, characterized in that, Placing the bimetallic strip in a temperature detection environment includes: The bimetallic strip is designed with a specific geometry that satisfies the requirements for abrupt displacement detection and gradual displacement detection at the detection end under temperature change conditions. The bimetallic strip is placed against a controllable heat source, causing the detection end to rise from an initial temperature T0 to a limiting temperature T. a Temperature changes that are either linearly accelerated or uniformly accelerated; The detection terminals collect data at the temperature detection threshold T. b The initial temperature T0 to the extreme temperature T a Location information and corresponding time points between them.

3. The temperature detection method based on bimetallic strip flip displacement according to claim 2, characterized in that, Also includes: The initial temperature T0 is increased to the extreme temperature T. a The corresponding positional distances between them are divided into equal parts, and at least into three equal parts, with each division point being a continuous detection point; An optical interruption triggering device is provided on the bimetallic strip flipping displacement path, including the temperature detection threshold T. b The corresponding flip displacement and the continuous detection points; When the detection end flips and shifts to the temperature detection threshold T b At the location and the continuous detection points, the optical path is blocked and the corresponding time nodes are collected synchronously.

4. The temperature detection method based on bimetallic strip flipping displacement according to claim 1, characterized in that, The thermal cycle is configured to raise the initial temperature T0 to the limiting temperature T. a To accelerate the heating process and with a required time of T1, the limiting temperature T a The temperature drops to the initial temperature T0 at a uniform rate, and the time required is T2, wherein T1... T2.

5. The temperature detection method based on bimetallic strip flipping displacement according to claim 1, characterized in that, The accuracy of temperature is judged based on the detection information, including: The temperature detection threshold T is obtained when the detection end reaches the specified temperature during multiple thermal cycles. b The historical set of offset positions; The historical set of offset positions is arranged in a time series on a two-dimensional plane to generate a cumulative displacement trajectory map; The linear drift state or nonlinear abrupt change state within the cycle of the thermal cycle is identified based on the cumulative displacement trajectory diagram. The durability degradation level of the bimetallic strip's temperature response accuracy is determined based on the linear drift state or the non-linear abrupt change state. The durability degradation level is used to quantitatively evaluate the degree of performance degradation of the bimetallic strip under the thermal cycling.

6. The temperature detection method based on bimetallic strip flip displacement according to claim 5, characterized in that, Determining the level of durability degradation includes: A parameter group consisting of the heating rate and the cooling rate in the temperature detection environment is associated with the control. Obtain the differences in the distribution characteristics of the historical set of offset positions under different heating and cooling rates; Based on the differences in distribution characteristics, a hysteresis correlation model is established to determine the dynamic response relationship between the displacement deviation of the bimetallic sheet and the temperature change rate of the thermal cycle. The threshold for determining the durability degradation level is corrected based on the displacement reference compensation amount output by the hysteresis correlation model.

7. The temperature detection method based on bimetallic strip flipping displacement according to claim 6, characterized in that, If the displacement change state is the linear drift state, the displacement reference compensation amount is added to all the determination thresholds of the durability degradation level; if it is the nonlinear abrupt change state, the absolute value of the displacement reference compensation amount is subtracted from the failure level determination threshold of the durability degradation level.

8. The temperature detection method based on bimetallic strip flip displacement according to claim 6, characterized in that, Establishing a lag correlation model includes: The historical set of offset positions corresponding to each group of heating rate and cooling rate is decomposed into thermal expansion displacement data sequence of temperature rising interval and cold contraction displacement data sequence of temperature falling interval. In the thermal expansion displacement data sequence, the temperature detection threshold T b A set of thermal expansion response slopes is obtained by dividing the data into segments based on reference points and performing multi-segment linear fitting. The same reference point division method is used to obtain the set of cold contraction response slopes in the cold contraction displacement data sequence. For the same temperature change range, the slope values ​​of the thermal expansion response slope set and the slope values ​​of the cold contraction response slope set are obtained, and the absolute difference value is calculated. The absolute difference values ​​of all ranges are collected to form a hysteresis feature dataset. Using the heating rate and the cooling rate as independent variables and the hysteresis feature dataset as the dependent variable, an analytical expression for the dynamic response relationship is generated based on the least squares fitting method, which serves as the hysteresis correlation model.

9. A temperature detection system based on bimetallic strip flipping displacement, characterized in that, The system includes: The tooling fixing module has one end of the bimetallic strip set as the fixed end and the end away from the fixed end set as the detection end. The fixed end is installed on the limit tooling, and the detection end is the flip displacement end that is affected by temperature changes. The temperature cycling module places the bimetallic strip in a temperature detection environment, which ranges from an initial temperature T0 to a limiting temperature T. a Thermal cycling occurs between them, T a >T0; Offset detection module, set temperature detection threshold T b And T a >T b >T0, and collect the temperature detection threshold T reached by the detection end during the thermal cycle of the temperature detection environment. b The corresponding offset position; The parameter control module controls the parameters in the temperature detection environment, including at least the heating rate, cooling rate, and extreme temperature, and obtains the corresponding detection information. The accuracy detection module determines the temperature accuracy of the bimetallic strip's flip displacement based on the detection information.

10. The temperature detection system based on bimetallic strip flipping displacement according to claim 9, characterized in that, The accuracy detection module includes: The historical information unit acquires the temperature detection threshold T reached by the detection end during multiple thermal cycles. b The historical set of offset positions; The image generation unit arranges the historical set of offset positions in a time series on a two-dimensional plane to generate a cumulative displacement trajectory map. The state recognition unit identifies the linear drift state or nonlinear abrupt change state within the cycle of thermal cycling based on the cumulative displacement trajectory diagram. The attenuation determination unit determines the durability attenuation level of the bimetallic strip's temperature response accuracy based on linear drift or nonlinear abrupt change. The durability attenuation level is used to quantitatively assess the degree of performance degradation of the bimetallic strip under thermal cycling.

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