Infrared switch and encoder length measuring method and system applied to tire

Abstract

The invention relates to the technical field of tire length measurement, and discloses an infrared switch and encoder length measurement method and system applied to a tire, a to-be-measured tire is pulled to pass through a length measurement station with constant tension through a conveying mechanism, an infrared switch and an encoder are arranged at the length measurement station, and the length of the tire is obtained; determining tire lengths corresponding to a plurality of historical sampling moments to obtain a tire length sequence, and performing linear fitting to obtain a first tire length measurement fluctuation factor; obtaining a response time deviation sequence of the infrared switch and a pulse counting deviation sequence of the encoder, and calculating a second tire length measurement fluctuation factor; performing weighted summation on the first tire length measurement fluctuation factor and the second tire length measurement fluctuation factor to obtain a comprehensive tire length measurement fluctuation factor, setting a traction strategy, and adopting a mode of combining an infrared switch and an encoder to ensure the measurement precision and efficiency of the tire length, comprehensively evaluating multiple fluctuation factors in the tire length measurement process, and improving the measurement accuracy of the tire length. And the automation level and the product quality of a production line are improved.

Description

Technical Field

[0001] This invention relates to the field of tire length measurement technology, and more specifically, to a method and system for measuring tire length using an infrared switch and encoder. Background Technology

[0002] With the rapid development of the tire manufacturing industry, the requirements for production efficiency and product quality are increasing. Length measurement control, as a key link in the tire production process, directly affects the product qualification rate and production line efficiency through its accuracy and stability.

[0003] Traditional length measurement methods often rely on contact-based mechanical measurements or a combination of single photoelectric sensor triggering and fixed pulse conversion. However, tires, being flexible, elastic materials with a certain surface texture, are prone to tension changes, deformation, or minor vibrations during traction and transportation. This leads to random errors and system drift in the measurement results of a single sensor. Especially in high-speed, continuous production environments, these errors can be amplified by sensor response delays, pulse count loss, or counting errors, causing unexpected fluctuations in the measured length value and making it difficult to reflect the true physical length of the tire. Summary of the Invention

[0004] This invention provides a method and system for measuring tire length using an infrared switch and encoder. By combining an infrared switch with an encoder, the accuracy and efficiency of tire length measurement are ensured. At the same time, multiple fluctuation factors in the tire length measurement process are comprehensively evaluated, thereby improving the automation level of the production line and product quality.

[0005] To achieve the above objectives, the present invention provides a method for measuring the length of a tire using an infrared switch and encoder, comprising: The tire to be tested is pulled through the length measuring station with constant tension by a conveying mechanism. An infrared switch and an encoder are set at the length measuring station to sample the length of the tire to be tested in real time and obtain the tire length. The tire lengths corresponding to multiple historical sampling times are determined to obtain a tire length sequence. The tire length sequence is linearly fitted, and the fluctuation changes are analyzed to obtain the first tire length measurement fluctuation factor. The response time deviation sequence of the infrared switch and the pulse count deviation sequence of the encoder are obtained, and the second tire length measurement fluctuation factor is calculated based on the synchronicity difference between the response time deviation sequence and the pulse count deviation sequence on the time axis. The first tire length measurement fluctuation factor and the second tire length measurement fluctuation factor are weighted and summed to obtain the comprehensive tire length measurement fluctuation factor, and the traction strategy of the tire under test is set according to the comprehensive tire length measurement fluctuation factor.

[0006] Furthermore, when the tire to be tested is pulled through the length measuring station with constant tension by the conveying mechanism, and an infrared switch and encoder are set at the length measuring station to sample the length of the tire in real time to obtain the tire length, the process includes: The infrared switch is deployed above the conveying mechanism, and the encoder is deployed at the end of the drive roller. The tread material within a preset length range extending along the conveying direction from the infrared switch trigger position at the current sampling time is denoted as the tread section to be tested. The infrared switch acquires the start trigger signal of the tread section to be tested, and the encoder records the transport length of the tread section to be tested to form the tire length of the tire to be tested at the current sampling time.

[0007] Furthermore, when performing linear fitting on the tire length sequence, analyzing fluctuation changes, and obtaining the first tire length measurement fluctuation factor, the process includes: A linear fit is performed on the tire lengths in the tire length sequence to obtain a straight line of tire lengths; Determine the slope and fitting error of the straight line along the tire length; Extract the maximum tire length and the minimum tire length from the tire length, and determine the relative rate of change of length based on the maximum tire length and the minimum tire length; The absolute value of the difference between the relative rate of change of length and the slope is determined as the length fluctuation difference; The product of the length fluctuation difference and the fitting error is used as the first tire length measurement fluctuation factor.

[0008] Further, when determining the relative rate of change of length based on the maximum tire length and the minimum tire length, the method includes: The absolute value of the difference between the maximum tire length and the minimum tire length is determined as the tire length difference; Determine the first historical sampling time corresponding to the maximum tire length, and determine the second historical sampling time corresponding to the minimum tire length; Determine the time interval between the first historical sampling time and the second historical sampling time; The ratio of the tire length difference to the time interval is taken as the relative rate of change of length.

[0009] Further, in acquiring the response time deviation sequence of the infrared switch and the pulse count deviation sequence of the encoder, the process includes: Within the sampling time range, record the actual response timestamp each time the infrared switch is triggered; Determine multiple differences between the actual response timestamp and the theoretical trigger timestamp, and construct the response time deviation sequence according to the triggering order; Within the sampling time range, record the actual number of pulses output by the encoder; Multiple differences between the actual number of pulses and the theoretical number of pulses are determined, and the pulse count deviation sequence is constructed according to the triggering order.

[0010] Further, when calculating the second tire length measurement fluctuation factor based on the synchronicity difference between the response time deviation sequence and the pulse count deviation sequence on the time axis, the following steps are included: The response time deviation sequence and the pulse count deviation sequence are normalized respectively. The ratio of the response time deviation in the normalized response time deviation sequence to the previous response time deviation is taken as the relative response time deviation. The ratio of the pulse count deviation in the normalized pulse count deviation sequence to the previous pulse count deviation is taken as the relative pulse count deviation. The sum of the absolute values ​​of the differences between all relative response time deviations and relative pulse count deviations is used as the second tire length measurement fluctuation factor.

[0011] Furthermore, before setting the traction strategy for the tire under test based on the comprehensive tire length fluctuation factor, the method further includes: Obtain the comprehensive tire length measurement fluctuation factor threshold. When the comprehensive tire length measurement fluctuation factor is less than the comprehensive tire length measurement fluctuation factor threshold, it is determined that there is no need to set the traction strategy for the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the comprehensive tire length measurement fluctuation factor threshold, it is determined that a traction strategy for the tire under test needs to be set.

[0012] Furthermore, when setting the traction strategy for the tire under test based on the comprehensive tire length fluctuation factor, the following steps are included: Collect the current traction speed of the conveying mechanism; The current traction speed is adjusted by reducing the speed based on the comprehensive tire length fluctuation factor.

[0013] Furthermore, when adjusting the current traction speed by reducing it based on the comprehensive tire length fluctuation factor, the following steps are included: The first preset comprehensive tire length measurement fluctuation factor, the second preset comprehensive tire length measurement fluctuation factor, and the third preset comprehensive tire length measurement fluctuation factor are preset. The first preset speed reduction adjustment value, the second preset speed reduction adjustment value, the third preset speed reduction adjustment value and the fourth preset speed reduction adjustment value are preset. When the comprehensive tire length measurement fluctuation factor is less than the first preset comprehensive tire length measurement fluctuation factor, the first product of the first preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the first preset comprehensive tire length measurement fluctuation factor and less than the second preset comprehensive tire length measurement fluctuation factor, the second product value of the second preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the second preset comprehensive tire length measurement fluctuation factor and less than the third preset comprehensive tire length measurement fluctuation factor, the third product value of the third preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the third preset comprehensive tire length measurement fluctuation factor, the fourth product of the fourth preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test.

[0014] To achieve the above objectives, the present invention also provides an infrared switch and encoder length measurement system for tires, comprising: The tire length measurement module is used to pull the tire to be tested through the length measurement station with constant tension via a conveying mechanism. An infrared switch and an encoder are set at the length measurement station to sample the length of the tire to be tested in real time to obtain the tire length. The first analysis module is used to determine the tire length corresponding to multiple historical sampling times, obtain a tire length sequence, perform linear fitting on the tire length sequence, analyze the fluctuation changes, and obtain a first tire length measurement fluctuation factor. The second analysis module is used to obtain the response time deviation sequence of the infrared switch and the pulse count deviation sequence of the encoder, and calculate the second tire length measurement fluctuation factor based on the synchronicity difference between the response time deviation sequence and the pulse count deviation sequence on the time axis. The strategy adjustment module is used to perform a weighted summation of the first tire length measurement fluctuation factor and the second tire length measurement fluctuation factor to obtain a comprehensive tire length measurement fluctuation factor, and to set the traction strategy of the tire under test based on the comprehensive tire length measurement fluctuation factor.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention discloses a method and system for measuring tire length using an infrared switch and encoder. The method involves using a conveying mechanism to traction the tire under test through a length measurement station with constant tension. An infrared switch and encoder are installed at the measurement station to obtain the tire length. The tire lengths corresponding to multiple historical sampling times are determined to obtain a tire length sequence, which is then linearly fitted to obtain a first tire length measurement fluctuation factor. The response time deviation sequence of the infrared switch and the pulse count deviation sequence of the encoder are obtained to calculate a second tire length measurement fluctuation factor. The first and second tire length measurement fluctuation factors are weighted and summed to obtain a comprehensive tire length measurement fluctuation factor. A traction strategy is set, and the combination of infrared switches and encoders ensures the accuracy and efficiency of tire length measurement. This comprehensive evaluation of multiple fluctuation factors in the tire length measurement process improves the automation level of the production line and product quality. Attached Figure Description

[0016] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A schematic flowchart of an infrared switch and encoder length measurement method for tires, according to an embodiment of the present invention, is shown. Figure 2 A schematic diagram of an infrared switch plus encoder length measurement system for tires, as shown in an embodiment of the present invention, is illustrated. Detailed Implementation

[0017] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0018] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0019] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0020] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" 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 between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0021] The following is a description of preferred embodiments of the present invention in conjunction with the accompanying drawings.

[0022] like Figure 1 As shown, an embodiment of the present invention discloses a method for measuring the length of a tire using an infrared switch and encoder, comprising: S110: The tire to be tested is pulled through the length measuring station with constant tension by the conveying mechanism. An infrared switch and an encoder are set at the length measuring station to sample the length of the tire to be tested in real time to obtain the tire length. In some embodiments of this application, when the tire to be tested is pulled through a length measuring station with constant tension by a conveying mechanism, and an infrared switch and encoder are installed at the length measuring station to sample the length of the tire to be tested in real time to obtain the tire length, the process includes: The infrared switch is deployed above the conveying mechanism, and the encoder is deployed at the end of the drive roller. The tread material within a preset length range extending along the conveying direction from the infrared switch trigger position at the current sampling time is denoted as the tread section to be tested. The infrared switch acquires the start trigger signal of the tread section to be tested, and the encoder records the transport length of the tread section to be tested to form the tire length of the tire to be tested at the current sampling time.

[0023] In this embodiment, the position of the tread segment to be tested is detected by an infrared switch, and the length of the tread segment to be tested is determined by an encoder.

[0024] The beneficial effects of the above technical solution are as follows: by deploying an infrared switch above the conveying mechanism and an encoder at the end of the drive roller, the starting position and conveying length of the tire under test can be accurately obtained, thus providing accurate tire length information. Utilizing the characteristics of the infrared switch and encoder, the infrared switch can respond quickly and trigger signals, while the encoder can accurately record the conveying length; the combination of the two improves the accuracy and efficiency of the measurement.

[0025] S120: Determine the tire length corresponding to multiple historical sampling times to obtain a tire length sequence, perform linear fitting on the tire length sequence, analyze the fluctuation changes, and obtain the first tire length measurement fluctuation factor; In this embodiment, each sampling moment corresponds to a tire length, thus obtaining a tire length sequence. The number of historical sampling moments is 12.

[0026] In some embodiments of this application, when performing linear fitting on the tire length sequence, analyzing fluctuation changes, and obtaining the first tire length measurement fluctuation factor, the following steps are included: A linear fit is performed on the tire lengths in the tire length sequence to obtain a straight line of tire lengths; Determine the slope and fitting error of the straight line along the tire length; Extract the maximum tire length and the minimum tire length from the tire length, and determine the relative rate of change of length based on the maximum tire length and the minimum tire length; The absolute value of the difference between the relative rate of change of length and the slope is determined as the length fluctuation difference; The product of the length fluctuation difference and the fitting error is used as the first tire length measurement fluctuation factor.

[0027] In this embodiment, the fitting error is determined based on the mean absolute error. The specific determination process is quite mature and will not be repeated here.

[0028] The beneficial effects of the above technical solution are as follows: By linearly fitting the tire length sequence, the trend of tire length change over a period of time can be intuitively reflected. The slope of the obtained straight line of tire length can reveal the overall rate of change of tire length, while the fitting error reflects the degree of deviation between the actual tire length and the fitted straight line, reflecting the accuracy of the measurement. Extracting the maximum and minimum tire lengths from the tire length and determining the relative rate of change of length can further reveal the fluctuation range of tire length. Using the product of the length fluctuation difference and the fitting error as the first tire length measurement fluctuation factor comprehensively considers the trend of tire length change, measurement accuracy, and fluctuation range, enabling a more comprehensive and accurate assessment of the fluctuation situation in the tire length measurement process, and providing a reliable basis for subsequently formulating corresponding strategies based on the fluctuation situation.

[0029] In some embodiments of this application, determining the relative rate of change of length based on the maximum tire length and the minimum tire length includes: The absolute value of the difference between the maximum tire length and the minimum tire length is determined as the tire length difference; Determine the first historical sampling time corresponding to the maximum tire length, and determine the second historical sampling time corresponding to the minimum tire length; Determine the time interval between the first historical sampling time and the second historical sampling time; The ratio of the tire length difference to the time interval is taken as the relative rate of change of length.

[0030] S130: Obtain the response time deviation sequence of the infrared switch and the pulse count deviation sequence of the encoder, and calculate the second tire length measurement fluctuation factor based on the synchronicity difference between the response time deviation sequence and the pulse count deviation sequence on the time axis. In some embodiments of this application, obtaining the response time deviation sequence of the infrared switch and the pulse count deviation sequence of the encoder includes: Within the sampling time range, record the actual response timestamp each time the infrared switch is triggered; Determine multiple differences between the actual response timestamp and the theoretical trigger timestamp, and construct the response time deviation sequence according to the triggering order; Within the sampling time range, record the actual number of pulses output by the encoder; Multiple differences between the actual number of pulses and the theoretical number of pulses are determined, and the pulse count deviation sequence is constructed according to the triggering order.

[0031] The beneficial effects of the above technical solution are as follows: By recording the actual response timestamp of the infrared switch each time it is triggered and the difference between it and the theoretical trigger timestamp, a response time deviation sequence is constructed, which can accurately reflect the response time fluctuation of the infrared switch during the measurement process. Similarly, by recording the difference between the actual number of pulses output by the encoder and the theoretical number of pulses, a pulse count deviation sequence is constructed, which can accurately reflect the pulse count fluctuation of the encoder during the measurement process. These two deviation sequences provide basic data for subsequent calculation of the second tire length measurement fluctuation factor, which helps to more comprehensively evaluate the fluctuation factors in the tire length measurement process and improve the accuracy and reliability of the measurement.

[0032] In some embodiments of this application, calculating the second tire length measurement fluctuation factor based on the synchronicity difference between the response time deviation sequence and the pulse count deviation sequence on the time axis includes: The response time deviation sequence and the pulse count deviation sequence are normalized respectively. The ratio of the response time deviation in the normalized response time deviation sequence to the previous response time deviation is taken as the relative response time deviation. The ratio of the pulse count deviation in the normalized pulse count deviation sequence to the previous pulse count deviation is taken as the relative pulse count deviation. The sum of the absolute values ​​of the differences between all relative response time deviations and relative pulse count deviations is used as the second tire length measurement fluctuation factor.

[0033] In this embodiment, the response time deviation sequence and the pulse count deviation sequence are normalized based on the max-min normalization method, and the response time deviation sequence and the pulse count deviation sequence are normalized to the range of [0,1].

[0034] In this embodiment, each response time deviation sequence corresponds one-to-one with the pulse count deviation sequence, and then they can be summed. Finally, all the summed values ​​are accumulated to obtain the second tire length measurement fluctuation factor.

[0035] The beneficial effects of the above technical solution are as follows: normalizing the response time deviation sequence and pulse count deviation sequence eliminates the influence of different dimensions, making them comparable and facilitating subsequent analysis. By calculating the relative response time deviation and relative pulse count deviation, the change of each deviation relative to the previous deviation can be more clearly seen, thus reflecting the fluctuation trend. By summing the absolute values ​​of the differences between all relative response time deviations and relative pulse count deviations, the resulting second tire length measurement fluctuation factor comprehensively considers the synchronicity difference between infrared switch response time fluctuation and encoder pulse count fluctuation on the time axis, enabling a more accurate assessment of their impact on tire length measurement fluctuation and providing strong support for the subsequent formulation of reasonable traction strategies.

[0036] S140: The first tire length measurement fluctuation factor and the second tire length measurement fluctuation factor are weighted and summed to obtain the comprehensive tire length measurement fluctuation factor, and the traction strategy of the tire under test is set according to the comprehensive tire length measurement fluctuation factor.

[0037] In this embodiment, a first weight is assigned to the first tire length measurement fluctuation factor, preferably 0.7, and a second weight is assigned to the second tire length measurement fluctuation factor, preferably 0.3.

[0038] In some embodiments of this application, before setting the traction strategy for the tire under test based on the comprehensive tire length fluctuation factor, the method further includes: Obtain the comprehensive tire length measurement fluctuation factor threshold. When the comprehensive tire length measurement fluctuation factor is less than the comprehensive tire length measurement fluctuation factor threshold, it is determined that there is no need to set the traction strategy for the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the comprehensive tire length measurement fluctuation factor threshold, it is determined that a traction strategy for the tire under test needs to be set.

[0039] In this embodiment, the optimal threshold for the comprehensive tire length measurement fluctuation factor is 2, but it can be adjusted adaptively according to actual needs.

[0040] The beneficial effects of the above technical solution are as follows: By assigning weights to the first tire length measurement fluctuation factor and the second tire length measurement fluctuation factor respectively and performing a weighted summation, a more comprehensive and accurate integrated tire length measurement fluctuation factor can be obtained by comprehensively considering multiple factors such as tire length change trend, measurement accuracy, fluctuation range, infrared switch response time fluctuation, and encoder pulse count fluctuation. The comparison between the integrated tire length measurement fluctuation factor and a set threshold determines whether a traction strategy for the tire under test needs to be set, making the formulation of the traction strategy more targeted and reasonable, avoiding unnecessary strategy adjustments, and improving the operating efficiency of the production line and the stability of product quality. When the integrated tire length measurement fluctuation factor is less than the threshold, it indicates that the tire length measurement process is relatively stable and no adjustment of the traction strategy is required; when the integrated tire length measurement fluctuation factor is greater than or equal to the threshold, it indicates that the length measurement process has experienced significant fluctuations. In this case, setting an appropriate traction strategy can effectively cope with the fluctuations, ensuring the accuracy and efficiency of tire length measurement, thereby improving the automation level of the entire production process and product quality.

[0041] In some embodiments of this application, when setting the traction strategy for the tire under test based on the comprehensive tire length measurement fluctuation factor, the following is included: Collect the current traction speed of the conveying mechanism; The current traction speed is adjusted by reducing the speed based on the comprehensive tire length fluctuation factor.

[0042] In this embodiment, the traction speed at the next moment is obtained by adjusting the current traction speed by reducing the current traction speed.

[0043] In some embodiments of this application, when adjusting the current traction speed by reducing the speed based on the comprehensive tire length fluctuation factor, the following methods are included: The first preset comprehensive tire length measurement fluctuation factor, the second preset comprehensive tire length measurement fluctuation factor, and the third preset comprehensive tire length measurement fluctuation factor are preset. The first preset speed reduction adjustment value, the second preset speed reduction adjustment value, the third preset speed reduction adjustment value and the fourth preset speed reduction adjustment value are preset. When the comprehensive tire length measurement fluctuation factor is less than the first preset comprehensive tire length measurement fluctuation factor, the first product of the first preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the first preset comprehensive tire length measurement fluctuation factor and less than the second preset comprehensive tire length measurement fluctuation factor, the second product value of the second preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the second preset comprehensive tire length measurement fluctuation factor and less than the third preset comprehensive tire length measurement fluctuation factor, the third product value of the third preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the third preset comprehensive tire length measurement fluctuation factor, the fourth product of the fourth preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test.

[0044] In this embodiment, the first preset comprehensive tire length measurement fluctuation factor is preferably 4, the second preset comprehensive tire length measurement fluctuation factor is preferably 6, and the third preset comprehensive tire length measurement fluctuation factor is preferably 8. The specific factors can be adjusted according to actual needs.

[0045] In this embodiment, the first preset speed reduction adjustment value is preferably 0.9, the second preset speed reduction adjustment value is preferably 0.85, the third preset speed reduction adjustment value is preferably 0.8, and the fourth preset speed reduction adjustment value is preferably 0.75. The specific values ​​can be adjusted according to actual needs.

[0046] In this embodiment, the product of the preset deceleration adjustment value and the current traction speed is used as the traction speed at the next sampling time.

[0047] The beneficial effects of the above technical solution are as follows: By pre-setting multiple preset comprehensive tire length measurement fluctuation factors and corresponding preset speed reduction adjustment values, the traction speed at the next sampling moment can be determined based on the specific value of the comprehensive tire length measurement fluctuation factor. The tiered adjustment method can more precisely address different degrees of length measurement fluctuations, making the adjustment of traction speed more reasonable and accurate. When the comprehensive tire length measurement fluctuation factor is small, it indicates that the length measurement process is relatively stable, requiring only a small speed reduction adjustment; conversely, when the comprehensive tire length measurement fluctuation factor is large, it indicates that the length measurement process has experienced significant fluctuations, and a larger speed reduction adjustment can effectively avoid affecting the accuracy and efficiency of tire length measurement due to excessive fluctuations. This strategy of flexibly adjusting the traction speed according to actual conditions helps improve the stability of the production line and product quality, reducing the adverse effects caused by traction fluctuations.

[0048] To further illustrate the technical concept of this invention, the technical solution of this invention will now be described in conjunction with specific application scenarios.

[0049] Correspondingly, such as Figure 2 As shown, this application also provides an infrared switch and encoder length measurement system for tires, comprising: The tire length measurement module is used to pull the tire to be tested through the length measurement station with constant tension via a conveying mechanism. An infrared switch and an encoder are set at the length measurement station to sample the length of the tire to be tested in real time to obtain the tire length. The first analysis module is used to determine the tire length corresponding to multiple historical sampling times, obtain a tire length sequence, perform linear fitting on the tire length sequence, analyze the fluctuation changes, and obtain a first tire length measurement fluctuation factor. The second analysis module is used to obtain the response time deviation sequence of the infrared switch and the pulse count deviation sequence of the encoder, and calculate the second tire length measurement fluctuation factor based on the synchronicity difference between the response time deviation sequence and the pulse count deviation sequence on the time axis. The strategy adjustment module is used to perform a weighted summation of the first tire length measurement fluctuation factor and the second tire length measurement fluctuation factor to obtain a comprehensive tire length measurement fluctuation factor, and to set the traction strategy of the tire under test based on the comprehensive tire length measurement fluctuation factor.

[0050] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0051] Although the invention has been described above with reference to embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, as long as there is no structural conflict, the features in the embodiments disclosed in this invention can be combined with each other in any way. The fact that not all of these combinations are described in this specification is merely for the sake of brevity and resource conservation.

[0052] It will be understood by those skilled in the art that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for measuring the length of tires using an infrared switch and encoder, characterized in that, include: The tire to be tested is pulled through the length measuring station with constant tension by a conveying mechanism. An infrared switch and an encoder are set at the length measuring station to sample the length of the tire to be tested in real time and obtain the tire length. The tire lengths corresponding to multiple historical sampling times are determined to obtain a tire length sequence. The tire length sequence is linearly fitted, and the fluctuation changes are analyzed to obtain the first tire length measurement fluctuation factor. The response time deviation sequence of the infrared switch and the pulse count deviation sequence of the encoder are obtained, and the second tire length measurement fluctuation factor is calculated based on the synchronicity difference between the response time deviation sequence and the pulse count deviation sequence on the time axis. The first tire length measurement fluctuation factor and the second tire length measurement fluctuation factor are weighted and summed to obtain the comprehensive tire length measurement fluctuation factor, and the traction strategy of the tire under test is set according to the comprehensive tire length measurement fluctuation factor.

2. The method for measuring tire length using an infrared switch and encoder according to claim 1, characterized in that, When the tire to be tested is pulled through the length measuring station with constant tension by a conveying mechanism, and an infrared switch and encoder are set at the length measuring station to sample the length of the tire in real time to obtain the tire length, the process includes: The infrared switch is deployed above the conveying mechanism, and the encoder is deployed at the end of the drive roller. The tread material within a preset length range extending along the conveying direction from the infrared switch trigger position at the current sampling time is denoted as the tread section to be tested. The infrared switch acquires the start trigger signal of the tread section to be tested, and the encoder records the transport length of the tread section to be tested to form the tire length of the tire to be tested at the current sampling time.

3. The method for measuring tire length using an infrared switch and encoder according to claim 1, characterized in that, When performing linear fitting on the tire length sequence and analyzing fluctuation changes to obtain the first tire length measurement fluctuation factor, the following steps are included: A linear fit is performed on the tire lengths in the tire length sequence to obtain a straight line of tire lengths; Determine the slope and fitting error of the straight line along the tire length; Extract the maximum tire length and the minimum tire length from the tire length, and determine the relative rate of change of length based on the maximum tire length and the minimum tire length; The absolute value of the difference between the relative rate of change of length and the slope is determined as the length fluctuation difference; The product of the length fluctuation difference and the fitting error is used as the first tire length measurement fluctuation factor.

4. The method for measuring tire length using an infrared switch and encoder according to claim 3, characterized in that, When determining the relative rate of change of length based on the maximum tire length and the minimum tire length, the following are included: The absolute value of the difference between the maximum tire length and the minimum tire length is determined as the tire length difference; Determine the first historical sampling time corresponding to the maximum tire length, and determine the second historical sampling time corresponding to the minimum tire length; Determine the time interval between the first historical sampling time and the second historical sampling time; The ratio of the tire length difference to the time interval is taken as the relative rate of change of length.

5. The method for measuring tire length using an infrared switch and encoder according to claim 1, characterized in that, When acquiring the response time deviation sequence of the infrared switch and the pulse count deviation sequence of the encoder, the following steps are included: Within the sampling time range, record the actual response timestamp each time the infrared switch is triggered; Determine multiple differences between the actual response timestamp and the theoretical trigger timestamp, and construct the response time deviation sequence according to the triggering order; Within the sampling time range, record the actual number of pulses output by the encoder; Multiple differences between the actual number of pulses and the theoretical number of pulses are determined, and the pulse count deviation sequence is constructed according to the triggering order.

6. The method for measuring tire length using an infrared switch and encoder according to claim 1, characterized in that, When calculating the second tire length measurement fluctuation factor based on the synchronicity difference between the response time deviation sequence and the pulse count deviation sequence on the time axis, the following steps are included: The response time deviation sequence and the pulse count deviation sequence are normalized respectively. The ratio of the response time deviation in the normalized response time deviation sequence to the previous response time deviation is taken as the relative response time deviation. The ratio of the pulse count deviation in the normalized pulse count deviation sequence to the previous pulse count deviation is taken as the relative pulse count deviation. The sum of the absolute values ​​of the differences between all relative response time deviations and relative pulse count deviations is used as the second tire length measurement fluctuation factor.

7. The method for measuring tire length using an infrared switch and encoder according to claim 1, characterized in that, Before setting the traction strategy for the tire under test based on the comprehensive tire length fluctuation factor, the method further includes: Obtain the comprehensive tire length measurement fluctuation factor threshold. When the comprehensive tire length measurement fluctuation factor is less than the comprehensive tire length measurement fluctuation factor threshold, it is determined that there is no need to set the traction strategy for the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the comprehensive tire length measurement fluctuation factor threshold, it is determined that a traction strategy for the tire under test needs to be set.

8. The method for measuring tire length using an infrared switch and encoder according to claim 1, characterized in that, When setting the traction strategy for the tire under test based on the comprehensive tire length fluctuation factor, the following steps are included: Collect the current traction speed of the conveying mechanism; The current traction speed is adjusted by reducing the speed based on the comprehensive tire length fluctuation factor.

9. The method for measuring tire length using an infrared switch and encoder according to claim 8, characterized in that, When adjusting the current traction speed by reducing the speed based on the comprehensive tire length fluctuation factor, the following are included: The first preset comprehensive tire length measurement fluctuation factor, the second preset comprehensive tire length measurement fluctuation factor, and the third preset comprehensive tire length measurement fluctuation factor are preset. The first preset speed reduction adjustment value, the second preset speed reduction adjustment value, the third preset speed reduction adjustment value and the fourth preset speed reduction adjustment value are preset. When the comprehensive tire length measurement fluctuation factor is less than the first preset comprehensive tire length measurement fluctuation factor, the first product of the first preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the first preset comprehensive tire length measurement fluctuation factor and less than the second preset comprehensive tire length measurement fluctuation factor, the second product value of the second preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the second preset comprehensive tire length measurement fluctuation factor and less than the third preset comprehensive tire length measurement fluctuation factor, the third product value of the third preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test. When the comprehensive tire length measurement fluctuation factor is greater than or equal to the third preset comprehensive tire length measurement fluctuation factor, the fourth product of the fourth preset deceleration adjustment value and the current traction speed is calculated as the traction strategy of the tire under test.

10. An infrared switch and encoder length measurement system for tires, applied to the infrared switch and encoder length measurement method for tires as described in any one of claims 1-9, characterized in that, include: The tire length measurement module is used to pull the tire to be tested through the length measurement station with constant tension via a conveying mechanism. An infrared switch and an encoder are set at the length measurement station to sample the length of the tire to be tested in real time to obtain the tire length. The first analysis module is used to determine the tire length corresponding to multiple historical sampling times, obtain a tire length sequence, perform linear fitting on the tire length sequence, analyze the fluctuation changes, and obtain a first tire length measurement fluctuation factor. The second analysis module is used to obtain the response time deviation sequence of the infrared switch and the pulse count deviation sequence of the encoder, and calculate the second tire length measurement fluctuation factor based on the synchronicity difference between the response time deviation sequence and the pulse count deviation sequence on the time axis. The strategy adjustment module is used to perform a weighted summation of the first tire length measurement fluctuation factor and the second tire length measurement fluctuation factor to obtain a comprehensive tire length measurement fluctuation factor, and to set the traction strategy of the tire under test based on the comprehensive tire length measurement fluctuation factor.

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