Hot runner temperature control system that recognizes thermocouples and heaters

Abstract

The present application relates to the technical field of hot runner temperature control, and discloses a hot runner temperature control system that can identify thermocouples and heaters, which includes a load, a relay control circuit, an operational amplifier circuit, and an MCU control circuit. During operation, the load first generates a first power. The first power signal is compared with the standard data pre-stored in the MCU control circuit to obtain a first comparison result. The MCU control circuit controls the relay to realize the positive and negative terminal conversion of the load, so that the load generates a second power again, and is processed by the operational amplifier circuit to form a second power signal. The signal is also compared with the standard data to obtain a second comparison result. Finally, based on the two comparison results, it is determined whether the load is a thermocouple or a heater. Here, the operational amplifier circuit adaptively adjusts its gain based on the signal characteristics of the first power to ensure that the signal is neither saturated due to excessive gain nor caused by insufficient gain.

Description

Technical Field

[0001] The present application relates to the technical field of hot runner temperature control, and more particularly, to a hot runner temperature control system capable of identifying thermocouples and heaters. Background Art

[0002] In the field of hot runner temperature control, accurately identifying thermocouples and heaters is crucial to ensuring system safety and efficiency. Existing technologies, such as patent CN114721449A, already provide a solution that prevents load damage caused by incorrect wiring and effectively distinguishes between thermocouples and heaters. However, with the increasing demand for industrial automation and precision manufacturing, the requirements for hot runner temperature control systems are becoming more stringent. Existing technologies still have room for improvement, especially in terms of high precision and high reliability.

[0003] Traditional hot runner temperature control systems typically rely on preset parameters or fixed algorithms to process signals from thermocouples or heaters. While this approach can meet basic requirements to a certain extent, it can lead to misjudgments due to variations in signal strength when used with different load types. This is particularly true in industrial environments, where environmental factors can make signal stability difficult to guarantee, increasing the probability of system errors. Furthermore, when encountering thermocouples and heaters with similar electrical characteristics, traditional methods may not make accurate judgments, potentially causing equipment malfunction or even damage.

[0004] Therefore, an optimized hot runner temperature control system that can identify thermocouples and heaters is desired. Summary of the Invention

[0005] The present application is proposed to address the above technical issues. The embodiments of the present application provide a hot runner temperature control system capable of identifying thermocouples and heaters, which uses an op amp circuit to adaptively adjust its gain based on the signal characteristics of a first-order electrical signal to ensure that the signal is neither saturated due to excessive gain nor lost due to insufficient gain.

[0006] According to one aspect of the present application, a hot runner temperature control system capable of identifying thermocouples and heaters is provided, comprising: a load, a relay control circuit, an operational amplifier circuit, and an MCU control circuit, wherein the load is bidirectionally connected to the relay control circuit, the other output end of the relay control circuit is connected to the operational amplifier circuit, the output end of the operational amplifier circuit is connected to the MCU control circuit, and the output end of the MCU control circuit is further connected to the other input end of the relay control circuit, wherein the operation process of the hot runner temperature control system comprises: the load generates a first electric power; the first electric power passes through the operational amplifier circuit to obtain a first electric power signal; the operational amplifier circuit generates ... The circuit adaptively adjusts its gain based on the signal characteristics of the first power; compares the first power signal with the standard data pre-stored in the MCU control circuit to obtain a first comparison result; the MCU control circuit controls the relay control circuit to achieve positive and negative terminal conversion of the load; the load generates a second power; the second power passes through the operational amplifier circuit to obtain a second power signal; the second power signal is compared with the standard data pre-stored in the MCU control circuit to obtain a second comparison result; based on the first comparison result and the second comparison result, the load type of the load is determined, and the load type is a thermocouple or a heater.

[0007] In the above hot runner temperature control system capable of identifying thermocouples and heaters, the first electrifying force is an initial electrifying force generated after the load is powered on at room temperature.

[0008] In the above-mentioned hot runner temperature control system that can identify thermocouples and heaters, the load type of the load is judged based on the first comparison result and the second comparison result, and the load type is a thermocouple or a heater, including: judging whether the first comparison result and the second comparison result are both within the data range of the heater; if so, determining that the load type is a heater; if not, judging that the load type is a thermocouple.

[0009] In the above-mentioned hot runner temperature control system that can identify thermocouples and heaters, the operational amplifier circuit adaptively adjusts its gain based on the signal characteristics of the first-generating force, including: sampling the first-generating force by the operational amplifier circuit to obtain a continuous data set of discrete potential sampling points; analyzing the continuous data set of discrete potential sampling points based on a predefined rule set to obtain a gain adjustment strategy.

[0010] In the above-mentioned hot runner temperature control system that can identify thermocouples and heaters, the continuous data set of the potential discrete sampling points is analyzed based on a predefined rule set to obtain a gain adjustment strategy, including: in response to the maximum value of five consecutive potential discrete sampling points in the continuous data set of the potential discrete sampling points exceeding 80% of the output range, reducing the gain with a first predetermined step size.

[0011] In the above hot runner temperature control system capable of identifying thermocouples and heaters, the first predetermined step size is reduced by 1 dB each time.

[0012] In the above-mentioned hot runner temperature control system that can identify thermocouples and heaters, the continuous data set of the potential discrete sampling points is analyzed based on a predefined rule set to obtain a gain adjustment strategy, including: in response to the minimum value of 5 consecutive potential discrete sampling points in the continuous data set of the potential discrete sampling points exceeding 20% of the output range, increasing the gain with a second predetermined step size, wherein the second predetermined step size is greater than the first predetermined step size.

[0013] In the above hot runner temperature control system capable of identifying thermocouples and heaters, the second predetermined step size is increased by 1.2 dB each time.

[0014] Compared with the prior art, the hot runner temperature control system provided by the present application, which can identify thermocouples and heaters, uses an operational amplifier circuit to adaptively adjust its gain based on the signal characteristics of the first power to ensure that the signal is neither saturated due to excessive gain nor caused by insufficient gain. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and other purposes, features, and advantages of the present application will become more apparent through a more detailed description of the embodiments of the present application in conjunction with the accompanying drawings. The accompanying drawings are intended to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the drawings, the same reference numerals generally represent the same components or steps.

[0016] Figure 1 The figure shows a functional module schematic diagram of a hot runner temperature control system according to an embodiment of the present application.

[0017] Figure 2 The figure shows a flow chart of the operation process of the hot runner temperature control system according to an embodiment of the present application.

[0018] Figure 3 The figure shows a logic diagram of determining the load type of the load based on the first comparison result and the second comparison result according to an embodiment of the present application, where the load type is a thermocouple or a heater.

[0019] Figure 4 The figure shows a flow chart of the operational amplifier circuit adaptively adjusting its gain based on the signal characteristics of the first power according to an embodiment of the present application.

[0020] Among them, 1. MCU control circuit; 2. operational amplifier circuit; 3. relay control circuit; 4. load; 41. thermocouple; 42. heater; 5. display end. DETAILED DESCRIPTION

[0021] Below, the exemplary embodiments according to the present application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application, and it should be understood that the present application is not limited to the exemplary embodiments described herein.

[0022] Figure 1 The figure shows a functional module diagram of a hot runner temperature control system according to an embodiment of the present application. Figure 1 As shown, the present application provides a hot runner temperature control system that can identify thermocouples and heaters, including: a load 4, a relay control circuit 3, an operational amplifier circuit 2 and an MCU control circuit 1, wherein the load 4 is bidirectionally connected to the relay control circuit 3, the other output end of the relay control circuit 3 is connected to the operational amplifier circuit 2, the output end of the operational amplifier circuit 2 is connected to the MCU control circuit 1, and the output end of the MCU control circuit 1 is further connected to the other input end of the relay control circuit 3, wherein the load type of the load 4 includes a thermocouple 41 and a heater 42, further, the hot runner temperature control system may also include a display end 5 connected to the MCU control circuit 1, and the display end 5 may be used to display the judgment result. Thus, it is convenient to intuitively see the judgment result on the display end 5.

[0023] Figure 2 FIG2 is a flow chart showing the operation process of the hot runner temperature control system according to an embodiment of the present application. Figure 2As shown, the operation process of the hot runner temperature control system includes: S1, the load generates a first power; S2, the first power passes through the operational amplifier circuit to obtain a first power signal, and the operational amplifier circuit adaptively adjusts its gain based on the signal characteristics of the first power; S3, the first power signal is compared with the standard data pre-stored in the MCU control circuit to obtain a first comparison result; S4, the MCU control circuit controls the relay control circuit to realize the positive and negative end conversion of the load; S5, the load generates a second power; S6, the second power passes through the operational amplifier circuit to obtain a second power signal; S7, the second power signal is compared with the standard data pre-stored in the MCU control circuit to obtain a second comparison result; S8, based on the first comparison result and the second comparison result, the load type of the load is judged, and the load type is a thermocouple or a heater.

[0024] In step S1, the load generates a first electromotive force. It should be understood that, at room temperature, when the load is powered on, an initial electromotive force (EMF) is generated, i.e., the first electromotive force. This electromotive force is a voltage signal naturally generated by the load without external interference, reflecting the load's electrical characteristics under static conditions. In other words, in one example, the first electromotive force is the initial electromotive force generated after the load is powered on at room temperature. At room temperature, this means the load begins operating without being affected by external temperature. This is because the electrical characteristics of thermocouples and heaters vary significantly at different temperatures. At room temperature, the differences are relatively small, making it more suitable for preliminary evaluation. Furthermore, selecting room temperature helps reduce the impact of external factors on measurement results and improves measurement accuracy. For example, measuring at high temperatures can cause signal distortion, affecting subsequent evaluation. Therefore, selecting room temperature as the starting condition ensures measurement stability while reflecting the load's basic characteristics.

[0025] In step S2, the first electric force passes through the operational amplifier circuit to obtain a first electric force signal, and the operational amplifier circuit adaptively adjusts its gain based on the signal characteristics of the first electric force. It should be understood that due to the differences in the physical structure and working principles of thermocouples and heaters, the electric forces they generate under the same conditions will also be different. In order to capture these subtle differences, the operational amplifier circuit is used to amplify the first electric force to form a first electric force signal. The operational amplifier circuit plays a crucial role here because it not only needs to be sensitive enough to amplify weak signals, but also needs to have the ability to adaptively adjust the gain to ensure that the output signal is neither saturated due to excessive gain nor caused by insufficient gain. Signal loss.

[0026] In step S3, the first power signal is compared with the standard data pre-stored in the MCU control circuit to obtain a first comparison result. It should be understood that at this stage, the MCU will compare the received first power signal with the internally stored standard data. Here, the standard data is pre-stored inside the MCU and represents the typical signal characteristics that the thermocouple and heater should produce under normal working conditions. For example, for a specific model of thermocouple, its initial electric force at room temperature may be a weak but stable voltage value; while the heater may exhibit a higher resistance characteristic. These characteristics are used to establish a standard data set for comparison. Through this comparison, the MCU can obtain the first comparison result. This step helps to initially understand what type of load the load may be. However, a single measurement cannot fully confirm the identity of the load, so further operations are required to verify the accuracy of the results.

[0027] In step S4, the MCU control circuit controls the relay control circuit to switch the positive and negative terminals of the load. It should be understood that, to obtain more information for the final judgment, the MCU control circuit will then send instructions to the relay control circuit to change the positive and negative terminal connections of the load. This switching is intended to simulate the behavior of the load in a different but related electrical environment. For example, thermocouples and heaters may exhibit different resistance changes or other electrical characteristics when the positive and negative polarity are reversed.

[0028] In step S5, the load generates a second initiating force. It should be understood that after the positive and negative terminals are converted, the load generates a new initiating force, referred to as the second initiating force. During this process, the direction of current flow within the load changes, which may cause changes in the electrical characteristics of certain types of loads, particularly those components that are sensitive to polarity. For example, a heater is typically symmetrical, and its resistance characteristics do not change significantly when the positive and negative polarity are reversed. However, a thermocouple may exhibit different resistance values or other electrical characteristics after polarity reversal due to its internal structure.

[0029] In steps S6 and S7, the second power is passed through the op amp circuit to obtain a second power signal, which is then compared with the standard data pre-stored in the MCU control circuit to obtain a second comparison result. It should be understood that the second power is also processed by the op amp circuit to become the second power signal, which is then sent back to the MCU control circuit for a second comparison. At this point, the MCU uses the previously stored standard data to re-evaluate the newly obtained signal and obtain a second comparison result.

[0030] In step S8, the load type of the load is determined based on the first comparison result and the second comparison result, and the load type is thermocouple or heater. It should be understood that the results of the two comparisons are combined to form the basis for determining the load type. Figure 3 FIG2 shows a logic diagram of determining the load type of the load based on the first comparison result and the second comparison result according to an embodiment of the present application, wherein the load type is a thermocouple or a heater. Figure 3 As shown, based on the first comparison result and the second comparison result, the load type of the load is judged, and the load type is a thermocouple or a heater, including: judging whether the first comparison result and the second comparison result are both within the data range of the heater; if so, determining that the load type is a heater; if not, judging that the load type is a thermocouple.

[0031] In a real-world application, suppose an unknown load is connected to a system. When the system starts up, the load generates a first burst of power at room temperature. This power signal is amplified by an op amp circuit and then fed into the MCU for a first comparison. If the characteristics of the first burst of power signal are closer to the standard data for a heater, the load is initially judged to be a heater. However, to further confirm this initial conclusion, the system performs a positive-to-negative terminal conversion operation, causing the load to generate a new burst of power (i.e., a second burst of power), which is amplified by the op amp circuit and then converted into a second burst of power signal. The MCU then performs a second comparison of the second burst of power signal with the standard data. If the second burst of power signal also meets the standard data for a heater, such as no significant change in resistance or remaining relatively stable after polarity reversal, the system can more confidently conclude that the load is a heater. Conversely, if the second burst of power signal exhibits characteristics similar to a thermocouple, such as a different resistance value or other electrical characteristics after polarity reversal, the load will ultimately be judged to be a thermocouple, even if the first comparison indicates a heater.

[0032] By adopting the above method, the true identity of the load can be identified as accurately as possible without damaging the load. Traditional methods often rely on simple resistance measurement or other single parameter detection. Although this method is simple and direct, it is prone to misjudgment in complex industrial application scenarios. By introducing the collection and comparison of two starting power signals, not only can the load characteristics be examined from multiple angles, but the reliability and accuracy of the judgment are also increased.

[0033] Furthermore, consider that gain determines how the op amp amplifies the input signal. For hot runner temperature control systems, the appropriate gain should be able to amplify the weak voltage signals generated by thermocouples or heaters to a level suitable for subsequent processing. However, excessive gain can lead to saturation, where the output reaches its limit and fails to accurately reflect the input change when the input signal slightly exceeds a certain range. Conversely, too low a gain may not be sufficient to significantly boost the signal strength. Specifically, thermocouples and heaters typically generate very small voltage changes, which require significant amplification for effective measurement and control. For example, the thermoelectromotive force generated by certain types of thermocouples may be only a few microvolts (μV) to tens of millivolts (mV). To make these signals suitable for subsequent processing (such as analog-to-digital conversion and comparison), they must be properly amplified by an op amp. The amplified signal should be within a range suitable for downstream circuitry. For example, if the analog signal is subsequently converted to a digital signal, this range should match the input range of the A / D converter to avoid information loss or distortion. However, when the op amp's gain is set too high, even slight input changes can cause the output to quickly reach the supply rails (i.e., its maximum or minimum value). This condition is known as saturation. Once saturation occurs, the output signal no longer linearly follows input changes, losing its true representation of the original signal. Furthermore, recovery from saturation can be delayed, affecting system response speed and accuracy. Excessive gain not only amplifies the desired signal but also disproportionately amplifies any background noise. This can degrade the signal-to-noise ratio, drowning the desired signal in the noise and compromising the quality of the final measurement. Setting the gain too low, while saturation and noise amplification can be avoided, the input signal may not be sufficiently amplified to trigger subsequent circuitry or provide sufficient resolution for accurate measurement. Especially when using a high-resolution A / D converter, insufficiently amplified signals can lead to increased quantization error, compromising overall system performance. Lower gain reduces the maximum signal amplitude that the system can handle, a limitation for applications that require monitoring wide temperature ranges or rapid temperature changes.

[0034] Therefore, the present application adds an adaptive gain adjustment mechanism, whereby the op amp circuit adaptively adjusts its gain based on the signal characteristics of the first power source. The application of this adaptive gain adjustment mechanism enables the op amp circuit to better adapt to the varying signal strengths generated by different loads, ensuring stable and reliable signal input even in harsh environments.

[0035] Figure 4 FIG2 shows a flow chart of the operation amplifier circuit adaptively adjusting its gain based on the signal characteristics of the first power according to an embodiment of the present application. Figure 4As shown, the operational amplifier circuit adaptively adjusts its gain based on the signal characteristics of the first electric power, including: S21, sampling the first electric power by the operational amplifier circuit to obtain a continuous data set of discrete potential sampling points; S22, analyzing the continuous data set of discrete potential sampling points based on a predefined rule set to obtain a gain adjustment strategy.

[0036] Specifically, in step S21, the op amp circuit samples the first electric potential through a high-speed A / D converter to obtain a series of discrete electric potential data points. These data points constitute a continuous data set, providing the basis for subsequent analysis. After each sampling, the newly acquired data point is added to a queue of fixed length, and the earliest sample is removed at the same time, so that the latest data points can always be kept for real-time analysis. In one example, a queue containing the latest 5 samples is used, which helps to capture the trend changes of the signal without being affected by transient noise.

[0037] Specifically, in step S22, the system will conduct an in-depth analysis of this continuous data set based on a predefined set of rules to develop a reasonable gain adjustment strategy. Specifically, when it is found that the maximum value of five consecutive discrete potential sampling points exceeds 80% of the output range of the op amp, the system will take measures to reduce the gain with a first predetermined step size (reduced by 1dB each time). This setting is to leave enough buffer space for the op amp to avoid approaching saturation while also preventing misjudgment due to occasional peaks. On the contrary, if the minimum value of five consecutive discrete potential sampling points is lower than 20% of the output range, the gain is increased with a second predetermined step size (increased by 1.2dB each time). Here, the reason why the second predetermined step size is larger than the first predetermined step size is that a smaller gain increase may not significantly improve the signal quality due to the presence of background noise, and a larger step size can restore the signal strength to an appropriate level more quickly.

[0038] That is, in one example, analyzing the continuous data set of discrete potential sampling points based on a predefined rule set to obtain a gain adjustment strategy includes: in response to the maximum value of five consecutive discrete potential sampling points in the continuous data set of discrete potential sampling points exceeding 80% of the output range, reducing the gain by a first predetermined step size. In one example, the first predetermined step size is a 1 dB reduction.

[0039] In one example, analyzing the continuous data set of discrete potential sampling points based on a predefined rule set to determine a gain adjustment strategy includes: in response to a minimum value of five consecutive discrete potential sampling points in the continuous data set of discrete potential sampling points exceeding 20% of the output range, increasing the gain by a second predetermined step size, wherein the second predetermined step size is greater than the first predetermined step size. In one example, the second predetermined step size is increased by 1.2 dB each time.

[0040] The above approach maximizes performance while maintaining high accuracy. First, by sampling the first power signal at high frequency and constructing a continuous data set, the true waveform of the signal is effectively captured, providing a solid data foundation for accurately assessing its strength. The gain adjustment strategy, based on a predefined set of rules, fully considers practical application scenarios. For example, the choice of thresholds of 80% and 20% prevents saturation while ensuring sufficient signal strength. More importantly, the use of different gain adjustment steps (1dB decrease vs. 1.2dB increase) reflects the principle of differentiated handling of different situations: For situations approaching saturation, a cautious approach is adopted, with the gain gradually reduced; for situations with excessively weak signals, a more aggressive gain increase can be made to quickly restore normal operation.

[0041] It's worth noting that each gain adjustment is gradual, rather than a sudden, drastic change. This ensures a smooth system transition and prevents instability caused by sudden changes. After each adjustment, the system waits for a period of time to return to a steady state before continuing to monitor signal characteristics to ensure the adjustment is as expected. Furthermore, to further enhance system reliability and robustness, upper and lower limits are implemented to prevent violations even in extreme conditions. It's understandable that the use of a gradual adjustment method is also driven by stability considerations. While a quick response may appear advantageous, it can actually cause unnecessary oscillations, which are detrimental to long-term stable operation. By making gradual adjustments in small steps, smooth gain changes can be achieved without impacting overall system performance. Furthermore, allowing the system ample time to reach a new steady state before making further decisions ensures that each adjustment is based on the most accurate information, thereby improving the reliability of the entire process.

[0042] Finally, the system incorporates additional safety measures to account for unexpected situations that may arise in real-world applications, such as power supply fluctuations and sensor failures. For example, upper and lower limits for gain adjustment can prevent the risk of loss of control under extreme conditions. Redundant verification mechanisms, such as dual-channel monitoring, further enhance the system's fault tolerance, ensuring that basic functionality can be maintained even if certain components fail.

[0043] In a specific example of the present application, since there is a disconnection triggering effect on the temperature control circuit when the load is a thermocouple, it is expected that when the gain is reduced by a first predetermined step size and the gain is increased by a second predetermined step size, the thermocouple will not be falsely triggered to cause false disconnection of the temperature control circuit. Therefore, in response to the judgment result that the load type is a thermocouple, the first predetermined step size and the second predetermined step size are corrected.

[0044] For example, in one example, the first predetermined step size and the second predetermined step size may be corrected with a weighting parameter greater than 0.9 and less than 1.

[0045] Furthermore, the weighting parameters are set according to the specific parameters of the thermocouple. For various types of thermocouples, such as J type (iron-constantan), K type (nickel-chromium-nickel silicon), N type (nickel-chromium-copper-nickel alloy), S type (platinum-rhodium 10-platinum), etc., and their measurement ranges are also different, such as J type -40°C to +750°C or -210°C to +1200°C, K type -200°C to +1372°C, N type -200°C to +1300°C, S type -50°C to +1600°C, in the embodiment of the present application, preferably, for the action mechanism of the first predetermined step size and the second predetermined step size, that is, the percentage relationship between the maximum value exceeding 80% of the output range and the minimum value exceeding 20% of the output range, the thermocouple accuracy is selected as one of the calibration reference parameters. Here, the thermocouple accuracy refers to the deviation between the thermocouple measurement result and the actual temperature, which generally includes ±0.75% and ±1.0%, which is recorded here as the first accuracy ratio. and the second precision ratio .

[0046] In addition, since the load voltage difference between the hot and cold ends of the thermocouple is also correlated with the potential, the temperature change error compensation of the hot and cold ends is required to ensure the compensation accuracy under high precision to reduce false triggering. Therefore, the voltage difference is obtained by taking the average value of the load voltage difference between the hot and cold ends of each type of thermocouple under each type. For example, in the case of J-type 59 μV / °C, K-type 41 μV / °C, and N-type 42 μV / °C, , which is converted into gain form as .

[0047] Therefore, assuming that the first predetermined step length and the second predetermined step length are recorded as and , then: .

[0048] That is, the steady-state precision interference noise is maintained based on the accuracy-based error interference sum response form, and the load voltage difference gain is superimposed to appropriately reduce the first predetermined step size and the second predetermined step size, thereby avoiding false triggering of the thermocouple and causing false disconnection of the temperature control circuit.

[0049] Moreover, since the accuracy parameters and load voltage difference parameters under different thermocouple types vary in a very small range, the above formula can be applied even when the thermocouple types are extended. For example, the accuracies of different thermocouple types are divided into high-precision and low-precision classes according to the mean, and the mean accuracy of each class is calculated separately to obtain the first accuracy ratio and the second accuracy ratio.

[0050] The present invention has the following advantages: through two independent and complementary signal acquisition and comparisons, not only can the characteristics of the load be examined from multiple angles, but also the reliability and accuracy of the judgment are increased. The traditional single parameter detection method is easily affected by external interference or measurement errors, leading to misjudgment. The present invention introduces two comparisons of the starting power signal, which can not only effectively reduce the impact of a single measurement error, but also capture the subtle differences in the load under different conditions, thereby improving the recognition accuracy. In addition, this method can complete the identification process without damaging the load, ensuring the safety and reliability of the system. For example, some types of loads may be sensitive to the direction of current, and directly applying high voltage may cause damage; by first performing a low voltage test and combining it with the positive and negative terminal conversion, accurate results can be obtained while protecting the load.

[0051] Dynamic gain adjustment ensures that no matter how weak or strong the input signal, it is appropriately amplified without saturation or loss of useful information. This adaptive gain adjustment mechanism not only improves the system's interference immunity but also enables stable operation in complex and changing operating environments. For example, in industrial environments, electromagnetic interference and noise generated by other electronic devices can be mixed into the signal, affecting measurement accuracy. The op amp's filtering effectively eliminates this interference, resulting in a purer signal. Furthermore, appropriate gain settings help extend the life of sensors and other components, reduce the probability of failure, and ensure long-term stability and reliability.

[0052] Gradual gain adjustment ensures a smooth system transition and prevents instability caused by sudden changes. Each gain adjustment is limited to approximately ±1dB, preventing the impact of large, sudden changes on system stability. Specifically, whenever the gain adjustment conditions are met, the MCU issues a command to the programmable gain amplifier (PGA) to gradually adjust the gain in small steps. This not only prevents over-adjustment but also ensures that each adjustment is based on the most accurate information, thereby improving the reliability of the entire process.

[0053] After each adjustment, the system waits at least 10 milliseconds for the signal to return to steady state before continuing to monitor signal characteristics to ensure the adjustment is effective. This gradual adjustment approach not only ensures a smooth transition but also reduces the possibility of false triggers. For example, a single threshold exceedance may be caused by transient noise or other temporary factors and does not necessarily represent a true increase in signal strength. By requiring multiple consecutive samples (e.g., five) to exceed the threshold, these brief anomalies can be effectively filtered out, improving judgment accuracy.

[0054] The basic principles of the present application have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, and effects mentioned in this application are merely illustrative and not restrictive, and it should not be assumed that these advantages, strengths, and effects are required of each embodiment of this application. In addition, the specific details disclosed above are merely illustrative and facilitating understanding, and are not restrictive. The above details do not limit this application to necessarily being implemented using the above specific details.

[0055] The block diagrams of the devices, devices, equipment, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, devices, equipment, and systems can be connected, arranged, or configured in any manner. Words such as "include," "comprise," "have," and the like are open-ended words, meaning "including but not limited to," and can be used interchangeably therewith. The words "or" and "and" used herein refer to the words "and / or" and can be used interchangeably therewith, unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to," and can be used interchangeably therewith.

[0056] It should also be noted that in the apparatus, device, and method of the present application, each component or each step can be decomposed and / or recombined, and such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0057] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0058] The above description has been provided for the purpose of illustration and description. Furthermore, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A hot runner temperature control system capable of identifying thermocouples and heaters, comprising: A load, a relay control circuit, an operational amplifier circuit, and an MCU control circuit, wherein the load is bidirectionally connected to the relay control circuit, the other output end of the relay control circuit is connected to the operational amplifier circuit, the output end of the operational amplifier circuit is connected to the MCU control circuit, and the output end of the MCU control circuit is further connected to the other input end of the relay control circuit. The operation process of the hot runner temperature control system includes: The load generates a first electric power; The first power passes through the operational amplifier circuit to obtain a first power signal, and the operational amplifier circuit adaptively adjusts its gain based on the signal characteristics of the first power; Comparing the first power signal with standard data pre-stored in the MCU control circuit to obtain a first comparison result; The MCU control circuit controls the relay control circuit to achieve positive and negative terminal conversion of the load; The load generates a second electric power; Passing the second power through the operational amplifier circuit to obtain a second power signal; Comparing the second power signal with standard data pre-stored in the MCU control circuit to obtain a second comparison result; Determining a load type of the load based on the first comparison result and the second comparison result, the load type being a thermocouple or a heater; The operational amplifier circuit adaptively adjusts its gain based on the signal characteristics of the first power, including: Sampling the first electric power by the operational amplifier circuit to obtain a continuous data set of discrete sampling points of electric potential; Analyzing the continuous data set of the potential discrete sampling points based on a predefined rule set to obtain a gain adjustment strategy, including: in response to a maximum value of five consecutive potential discrete sampling points in the continuous data set of the potential discrete sampling points exceeding 80% of an output range, reducing the gain with a first predetermined step size; in response to a minimum value of five consecutive potential discrete sampling points in the continuous data set of the potential discrete sampling points being lower than 20% of the output range, increasing the gain with a second predetermined step size, wherein the second predetermined step size is greater than the first predetermined step size; Wherein, when the load is a thermocouple, the process of setting the first predetermined step length and the second predetermined step length includes: extracting an initial value of the first predetermined step length and an initial value of the second predetermined step length; extracting a first precision ratio and a second precision ratio of the thermocouple; Obtaining a voltage difference of the thermocouple and converting the voltage difference into a gain form; Based on the first precision ratio, the second precision ratio, and the gain form, the first predetermined step size and the second predetermined step size are optimized to obtain an optimized first predetermined step size and an optimized second predetermined step size.

2. The hot runner temperature control system capable of identifying thermocouples and heaters according to claim 1, characterized in that: The first electrifying power is the initial electrifying power generated after the load is powered on at room temperature.

3. The hot runner temperature control system capable of identifying thermocouples and heaters according to claim 2, characterized in that: Determining the load type of the load based on the first comparison result and the second comparison result, where the load type is a thermocouple or a heater, includes: Determine whether the first comparison result and the second comparison result are both within the data range of the heater; If yes, determining that the load type is a heater; If not, it is determined that the load type is a thermocouple.

4. The hot runner temperature control system capable of identifying thermocouples and heaters according to claim 3, characterized in that: The first predetermined step size is reduced by 1 dB each time.

5. The hot runner temperature control system capable of identifying thermocouples and heaters according to claim 4, characterized in that: The second predetermined step size increases by 1.2 dB each time.

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