PTC (Positive Temperature Coefficient) heating body and safety detection system and detection method thereof

Abstract

The invention relates to a PTC heating body and a safety detection system and method thereof, and the system comprises a supporting module, a humidity sensing module, and a main control module. The supporting module fixes the humidity sensing module between an aluminum pipe and a cooling fin in the PTC heating body. The humidity sensing module detects real-time humidity data around the aluminum pipe and sends the real-time humidity data to the main control module, the main control module compares the real-time humidity data with a preset humidity threshold value, and if the real-time humidity data is not smaller than the preset humidity threshold value, the PTC heating body is closed. In the whole process, when it is detected that the real-time humidity data is not smaller than the preset humidity threshold value, it is indicated that water possibly enters the aluminum pipe at the moment, the PTC heating body is turned off at the moment, the situation that the aluminum pipe explodes or cracks and the like is avoided, and it is ensured that the PTC heating body works safely.

Description

Technical Field

[0001] This application relates to the field of safety detection technology, and in particular to a PTC heating element (Positive Temperature Coefficient Thermistor Heater) and its safety detection system and method. Background Technology

[0002] PTC heating elements, as widely used heating components, play a crucial role in numerous fields, such as fan heaters and auxiliary heating in air conditioners in the home appliance industry, drying equipment in the industrial field, and seat heating in the automotive industry. Their core working principle utilizes an internal aluminum tube as a heat transfer medium to efficiently transfer the heat generated by the PTC element to a heat sink, thereby achieving the heating function for the external environment. This design gives PTC heating elements advantages such as rapid heating, high thermal efficiency, and temperature self-limitation, meeting heating needs in various scenarios to a certain extent.

[0003] Currently, the sealing between the aluminum tube and the external environment of a PTC heating element is mainly achieved using silicone sealant. This sealing method introduces the risk of water vapor entering the aluminum tube. When water vapor or other impurities seep into the aluminum tube, they will expand rapidly under the high-temperature environment in which the PTC heating element operates normally. Due to the limited internal space of the aluminum tube, the pressure generated by the expansion will increase dramatically. When the pressure exceeds the aluminum tube's withstand limit, it will cause the aluminum tube to rupture. In more severe cases, it may even explode. A rupture or explosion of the aluminum tube will not only completely disable the PTC heating element, affecting the normal operation of the equipment, but may also cause serious damage to surrounding personnel and equipment, leading to a safety accident.

[0004] Therefore, there is an urgent need for a safety testing solution for PTC heating elements to ensure their normal operation. Summary of the Invention

[0005] Therefore, it is necessary to provide a PTC heating element safety detection system and detection method that can ensure the safe operation of PTC heating elements, addressing the technical problems of safety risks inherent in traditional PTC heating elements; in addition, a safe PTC heating element is also provided.

[0006] In a first aspect, this application provides a PTC heating element safety detection system, including a support module, a humidity sensing module, and a main control module;

[0007] The support module is used to fix the humidity sensing module between the aluminum tube and the heat sink in the PTC heating element.

[0008] The humidity sensing module is used to detect real-time humidity data around the aluminum tube and send the real-time humidity data to the main control module;

[0009] The main control module is used to compare the real-time humidity data with a preset humidity threshold. If the real-time humidity data is not less than the preset humidity threshold, the PTC heating element is turned off.

[0010] In one embodiment, the support module is further used to fix the humidity sensing module to the outer surface of the aluminum tube in the PTC heating element and to be located at the air outlet or air return outlet of the PTC heating element.

[0011] In one embodiment, the support module includes a bracket and an air guide assembly, the air guide assembly being used to form a stable airflow path between the aluminum tube and the heat sink, and the bracket being used to fix the humidity sensing module to the stable airflow path.

[0012] In one embodiment, the humidity sensing module includes a humidity sensor and a ventilation assembly, the ventilation assembly being used to form a return air path, and the humidity sensor being disposed on the return air path.

[0013] In one embodiment, the humidity sensing module further includes an optocoupler component, through which the humidity sensor sends the collected real-time humidity data to the main control module.

[0014] In one embodiment, the humidity sensor includes a humidity sensor of model SHT35.

[0015] In one embodiment, the preset humidity threshold is 60%.

[0016] Secondly, this application provides a PTC heating element safety detection method, applied to the aforementioned PTC heating element safety detection system. The method includes:

[0017] Obtain real-time humidity data around the aluminum tube;

[0018] The real-time humidity data is compared with a preset humidity threshold.

[0019] If the real-time humidity data is not less than the preset humidity threshold, a PTC heating element shutdown signal is output.

[0020] In one embodiment, comparing the real-time humidity data with a preset humidity threshold includes:

[0021] The real-time humidity data is filtered to obtain effective real-time humidity data;

[0022] The effective real-time humidity data is compared with a preset humidity threshold.

[0023] The filtering process includes at least one of the following: moving average filtering, median filtering, threshold filtering, adaptive filtering, and data interpolation filtering.

[0024] Thirdly, this application also provides a PTC heating element, including an aluminum tube, a heat sink, and the aforementioned PTC heating element safety detection system.

[0025] The aforementioned PTC heating element safety detection system and method include a detection system comprising a support module, a humidity sensing module, and a main control module. The support module fixes the humidity sensing module between the aluminum tube and the heat sink in the PTC heating element. The humidity sensing module detects real-time humidity data around the aluminum tube and sends it to the main control module. The main control module compares the real-time humidity data with a preset humidity threshold. If the real-time humidity data is not less than the preset humidity threshold, the PTC heating element is shut down. Throughout the process, when the detected real-time humidity data is not less than the preset humidity threshold, it indicates that water may have entered the aluminum tube. At this point, the PTC heating element is shut down to prevent the aluminum tube from exploding or rupturing, ensuring the safe operation of the PTC heating element. Furthermore, the PTC heating element of this application includes the aforementioned PTC heating element safety detection system, which can effectively detect potential water ingress inside the aluminum tube and automatically shut down the PTC heating element, thereby achieving safe operation of the PTC heating element. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the PTC heating element in one embodiment;

[0027] Figure 2 This is a schematic diagram of the structure of a PTC heating element safety detection system in one embodiment;

[0028] Figure 3 This is a flowchart illustrating a safety testing method for a PTC heating element in one embodiment;

[0029] Figure 4 This is a flowchart illustrating a safety testing method for PTC heating elements in a specific application example. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0031] To explain in detail the technical concept and significant technical effects of the PTC heating element and its safety detection system and method in this application, the basic content will be introduced first below.

[0032] like Figure 1 As shown, in traditional technology, the PTC heating element consists of an aluminum tube and a heat sink. Its working principle involves transferring heat to the heat sink through the internal aluminum tube. However, because the aluminum tube is sealed to the outside with silicone, this seal is often not secure enough. Once water vapor or other impurities seep into the aluminum tube, these substances will expand rapidly under high temperatures, causing the aluminum tube to rupture or even explode, ultimately rendering the PTC heating element ineffective.

[0033] To address the problem of poor sealing of aluminum tubes in traditional PTC heating elements, which allows water vapor to enter and expand, potentially causing the aluminum tube to rupture or explode, thus leading to PTC heating element failure, this application proposes incorporating a humidity sensing module into the PTC heating element. This module monitors internal humidity in real time, identifies faults early, and effectively prevents the aluminum tube from rupturing or exploding due to excessive internal pressure, ensuring the safe and stable operation of the equipment. Specifically, this application integrates a humidity sensing module into the PTC heating element for real-time monitoring of the internal environment. When the humidity sensing module detects abnormal humidity, it automatically triggers an alarm or takes appropriate measures, such as cutting off the power supply, to prevent damage to the aluminum tube due to excessive internal pressure.

[0034] like Figure 2 As shown, this application discloses a PTC heating element safety detection system, which includes a support module 100, a humidity sensing module 200, and a main control module 300.

[0035] The support module 100 is used to fix the humidity sensing module 200 between the aluminum tube and the heat sink in the PTC heating element; the humidity sensing module 200 is used to detect the real-time humidity data around the aluminum tube and send the real-time humidity data to the main control module 300; the main control module 300 is used to compare the real-time humidity data with the preset humidity threshold, and if the real-time humidity data is not less than the preset humidity threshold, the PTC heating element is turned off.

[0036] The main function of the support module 100 is to fix the humidity sensing module 200 between the aluminum tube and the heat sink in the PTC heating element. In practical applications, due to the limited space between the aluminum tube and the heat sink, the support module 100 needs to adopt a suitable design and material to ensure that the humidity sensing module 200 can be stably installed without adversely affecting the normal heat dissipation and other performance of the PTC heating element. Specifically, the support module 100 can be made of high-temperature resistant ceramic material. Its shape is designed as a snap-fit ​​structure that adapts to the gap between the aluminum tube and the heat sink, which can easily clamp the humidity sensing module 200 in the designated position. During installation, simply align the end of the support module 100 with the snap-fit ​​with the gap between the aluminum tube and the heat sink, and press gently to complete the installation; the operation is simple and convenient. Moreover, this ceramic material support module 100 is not easily deformed in high-temperature environments, ensuring that the humidity sensing module 200 is stably fixed in its original position for a long time.

[0037] The humidity sensing module 200 may include an embedded humidity sensor, which is miniaturized for easy installation in the limited space between the aluminum tube and the heat sink. The humidity sensor typically consists of a sensing element, signal processing circuitry, and a housing. The humidity sensing module 200 is embedded in the gap between the aluminum tube and the heat sink. To ensure the stability and accuracy of the sensor's operation, sufficient ventilation holes are needed around it to allow free airflow. This allows the sensor to fully sense the ambient humidity around the aluminum tube, avoiding inaccurate humidity detection due to localized poor air circulation. For example, when installing the humidity sensing module 200, small ventilation holes can be pre-machined on the aluminum tube and heat sink, or ventilation slots can be designed on the support module 100 to ensure smooth airflow through the humidity sensing module 200.

[0038] The main control module 300 is the core control component of the entire PTC heating element safety detection system. Its main function is to receive real-time humidity data sent by the humidity sensing module 200 and compare this data with a preset humidity threshold. If the real-time humidity data is not less than the preset threshold, it indicates that the humidity around the aluminum tube has reached a level that may affect the safe operation of the PTC heating element. In this case, the main control module 300 will issue a shutdown command to turn off the PTC heating element to prevent safety accidents caused by excessive humidity. In practical applications, the main control module 300 can use a microcontroller as the core control chip. Specifically, the preset humidity threshold is pre-set in the main control module 300 through programming. This threshold can be reasonably set according to the actual operating environment and safety requirements of the PTC heating element. When the main control module 300 receives the real-time humidity data sent by the humidity sensing module 200, it compares it with the preset humidity threshold. If the real-time humidity data is greater than or equal to the preset threshold, the main control module 300 will immediately send a shutdown signal to the power switch of the PTC heating element through the control circuit, cutting off the power supply to the PTC heating element and stopping its operation. Meanwhile, the main control module 300 can also be equipped with a display device, such as an LCD screen, to display the current humidity data and system operating status in real time, facilitating user monitoring and management. Furthermore, the main control module 300 can connect to the humidity sensor module 200 via wireless communication to receive real-time humidity data sent by the humidity sensor module 200.

[0039] Specifically, the preset humidity threshold is 60%. In practical applications, a relative humidity between 40% and 60% is considered normal. Reaching 60% relative humidity indicates excessive humidity around the aluminum tube, making water seepage highly likely. In this case, the main control module 300 will shut down the PTC heating element. Furthermore, the main control module 300 can also send an alarm signal to the alarm device to alert the user to any abnormalities in the PTC.

[0040] The aforementioned PTC heating element safety detection system includes a support module 100, a humidity sensing module 200, and a main control module 300. The support module 100 fixes the humidity sensing module 200 between the aluminum tube and the heat sink in the PTC heating element. The humidity sensing module 200 detects real-time humidity data around the aluminum tube and sends it to the main control module 300. The main control module 300 compares the real-time humidity data with a preset humidity threshold. If the real-time humidity data is not less than the preset humidity threshold, the PTC heating element is turned off. Throughout the process, when the detected real-time humidity data is not less than the preset humidity threshold, it indicates that water may have entered the aluminum tube. At this time, the PTC heating element is turned off to prevent the aluminum tube from exploding or rupturing, ensuring the safe operation of the PTC heating element.

[0041] In one embodiment, the support module is also used to fix the humidity sensing module to the outer surface of the aluminum tube in the PTC heating element and to be located at the air outlet or air return outlet of the PTC heating element.

[0042] The support module plays a dual role. Firstly, it secures the humidity sensor module to the outer surface of the aluminum tube within the PTC heating element, positioned at either the air outlet or return air inlet. This placement is carefully considered, as the air outlet and return air inlet are critical areas for airflow within the PTC heating element. Installing the humidity sensor module here allows the sensor to more directly and quickly detect changes in humidity around the aluminum tube caused by airflow, improving the timeliness and accuracy of humidity detection. Secondly, the support module uses a high-temperature resistant material to secure the sensor at a safe distance, preventing damage from excessive heat due to close proximity to the aluminum tube. Furthermore, the design of air guide channels or ventilation holes ensures the sensor operates within a stable airflow path, preventing localized overheating and ensuring stable operation in a suitable environment. In practical applications, the support module can be constructed using various high-temperature resistant materials, such as polyimide, ceramic, and stainless steel. Polyimide possesses excellent high-temperature resistance, allowing for long-term use within a temperature range of -269℃ to +400℃. It also exhibits good insulation and mechanical properties, providing stable support for the humidity sensing module. Ceramic materials have extremely high heat resistance, with melting points typically above 2000℃, and good chemical stability, resisting chemical reactions with the surrounding environment. This effectively protects the humidity sensing module from high temperatures and chemical corrosion. Stainless steel offers high strength and corrosion resistance, resisting deformation at high temperatures and ensuring the structural stability of the support module, guaranteeing its long-term fixation in the designated position.

[0043] In one embodiment, the support module includes a bracket and an air guide assembly, the air guide assembly being used to form a stable airflow path between the aluminum tube and the heat sink, and the bracket being used to fix the humidity sensing module to the stable airflow path.

[0044] The airflow guiding assembly specifically includes an airflow guide plate and airflow guide channels. The airflow guide plate has a flat structure and is made of lightweight and high-temperature resistant materials, such as polyimide film or aluminum alloy sheet. Polyimide film has excellent high-temperature resistance and can be used for extended periods in a temperature range of -269℃ to +400℃, while also possessing good flexibility and insulation properties; aluminum alloy sheet is lightweight, high-strength, and easy to process and shape. The airflow guide channels are elongated groove structures set on the airflow guide plate, and their shape and size are optimized according to the airflow characteristics. The airflow guiding assembly is installed between the aluminum tube and the heat sink. By rationally arranging the airflow guide plate and airflow guide channels, the airflow is guided to flow along a specific path, forming a stable airflow path between the aluminum tube and the heat sink. The tilt angle of the airflow guide plate and the direction of the airflow guide channels are precisely designed according to the heat dissipation requirements of the heat-generating element and the airflow distribution.

[0045] In one embodiment, the humidity sensing module includes a humidity sensor and a ventilation assembly, the ventilation assembly being used to form a return air path, and the humidity sensor being disposed on the return air path.

[0046] In this embodiment, the humidity sensing module mainly consists of a humidity sensor and a ventilation component. The ventilation component is designed to create a return air path, on which the humidity sensor is positioned to ensure rapid response to changes in indoor humidity. Specifically, the ventilation component can be ventilated with openings around the humidity sensor to prevent stagnant airflow. Furthermore, the ventilation component may include a fine filter to prevent dust from entering the humidity sensor, ensuring its normal operation without obstructing airflow.

[0047] In one embodiment, the humidity sensing module further includes an optocoupler component, through which the humidity sensor sends the collected real-time humidity data to the main control module.

[0048] In this embodiment, the humidity sensing module mainly consists of a humidity sensor, a ventilation component, an optocoupler component, a filtering circuit, and a main control module. The ventilation component forms a return air path, and the humidity sensor is placed on the return air path to quickly respond to changes in indoor humidity. Under high-temperature conditions, to ensure that the real-time humidity data collected by the humidity sensor can be stably transmitted to the main control module, a series of targeted technical measures are adopted, including selecting a high-temperature resistant and interference-resistant humidity sensor, using an optocoupler component to isolate the sensor signal from the main control module, adding a filtering circuit at the signal input end to suppress high-frequency interference, and combining AI algorithms for data correction and anomaly detection. Furthermore, the humidity sensor includes the SHT35 model. The SHT35 has excellent performance with high accuracy and a wide temperature range (-40℃~125℃). Due to its good high-temperature resistance and measurement accuracy, it is suitable for use near PTC heating elements; this model of sensor has a high-temperature resistant package, which can maintain stable performance at high temperatures.

[0049] like Figure 3 As shown, this application discloses a safety detection method for a PTC heating element, applied to the aforementioned PTC heating element safety detection system. The method includes:

[0050] S200: Acquires real-time humidity data around the aluminum tube.

[0051] S400: Compares real-time humidity data with preset humidity thresholds.

[0052] S600: If the real-time humidity data is not less than the preset humidity threshold, output a PTC heating element shutdown signal.

[0053] like Figure 4 In practical applications, the PTC heating element responds to the user's startup operation. At this time, the humidity sensing module is first activated to detect the air humidity around the aluminum tube inside the PTC heating element. If the humidity is less than the preset humidity threshold, the PTC heating element is turned on normally; if the humidity is not less than the preset humidity threshold, the PTC heating element is turned off, and an alarm process is initiated to notify the user that the PTC heating element has an abnormality.

[0054] The aforementioned PTC heating element safety detection method includes a detection system comprising a support module, a humidity sensing module, and a main control module. The support module fixes the humidity sensing module between the aluminum tube and the heat sink within the PTC heating element. The humidity sensing module detects real-time humidity data around the aluminum tube and sends it to the main control module. The main control module compares the real-time humidity data with a preset humidity threshold. If the real-time humidity data is not lower than the preset humidity threshold, the PTC heating element is shut down. Throughout the process, when the detected real-time humidity data is not lower than the preset humidity threshold, it indicates that water may have entered the aluminum tube. In this case, the PTC heating element is shut down to prevent the aluminum tube from exploding or rupturing, ensuring the safe operation of the PTC heating element.

[0055] In one embodiment, comparing real-time humidity data with a preset humidity threshold includes: filtering the real-time humidity data to obtain effective real-time humidity data; comparing the effective real-time humidity data with the preset humidity threshold; wherein the filtering process includes at least one of the following: moving average filtering, median filtering, threshold filtering, adaptive filtering, and data interpolation filtering.

[0056] Moving average filtering is a simple and effective filtering method. It smooths data and reduces the impact of random noise by calculating the average of a certain number of continuously sampled data points. Specifically, a sliding window is set, containing a fixed number of sampled data points. Each time, the average of all data points in the window is calculated as the current valid data output. Then, the window slides forward one data point, and the above calculation process is repeated.

[0057] Median filtering involves arranging a set of data in ascending order and taking the middle value as the filtered result. This method is very effective at removing impulse noise (i.e., abnormal spikes or troughs in the data) because it is unaffected by extreme values.

[0058] Threshold filtering filters real-time humidity data based on pre-set upper and lower thresholds. If the data exceeds the set threshold range, it is considered abnormal and is removed or corrected; if the data is within the threshold range, it is retained as valid data.

[0059] Adaptive filtering automatically adjusts filter parameters based on the statistical characteristics of the input data to adapt to noise characteristics in different environments. It dynamically adjusts the filter coefficients by continuously estimating the statistical characteristics of the input signal and noise, thereby achieving the best filtering effect on the signal. An adaptive filtering algorithm, such as the Least Mean Square (LMS) algorithm, is selected. The filter coefficients are initialized, for example, set to 0 or based on empirical values. Each time new humidity data is acquired, it is input as the adaptive filter signal. The filter automatically adjusts the filter coefficients using the LMS algorithm based on the input signal and a pre-defined target signal (e.g., an ideal noise-free humidity signal, which can be obtained through historical data or model simulation), minimizing the error between the output signal and the target signal. The output signal after adaptive filtering is the effective real-time humidity data.

[0060] Data interpolation filtering is used to estimate the missing or outlier data values ​​based on the known distribution patterns of the data when data is missing or anomaly-prone. Commonly used interpolation methods include linear interpolation, quadratic interpolation, and spline interpolation.

[0061] The effective real-time humidity data obtained after the above filtering process will be sent to the comparison module for comparison with a preset humidity threshold. The preset humidity threshold is set according to the specific application scenario and requirements, and the preset humidity threshold range is set to 40%RH (relative humidity) to 60%RH. Through simple logical judgment, if the effective real-time humidity data is within the preset threshold range, the ambient humidity is determined to be normal; if the data is higher than the upper limit threshold, the ambient humidity is determined to be too high, and at this time, the PTC heating element poses a safety risk and needs to be turned off.

[0062] In addition, this application also provides a PTC heating element, including an aluminum tube, a heat sink, and a safety detection system for the aforementioned PTC heating element.

[0063] In general, in specific application examples, a humidity sensor is embedded inside the PTC heating element to accurately monitor changes in its internal environment. This humidity sensor connects to the main control module via a plug-in connection and transmits the collected humidity data to the main control module in real time. The main control module analyzes the received data to determine if a preset humidity threshold has been reached. Once the humidity reaches the threshold, the main control module immediately triggers an alarm, issuing an alarm signal to remind the user to take appropriate measures. Furthermore, if an abnormality is detected, the main control module controls the power supply to cut off the power to prevent damage to the aluminum tube due to excessive internal pressure, thereby ensuring the safe operation of the equipment.

[0064] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0065] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A PTC heating element safety detection system, characterized in that, It includes a support module, a humidity sensing module, and a main control module; The support module is used to fix the humidity sensing module between the aluminum tube and the heat sink in the PTC heating element. The humidity sensing module is used to detect real-time humidity data around the aluminum tube and send the real-time humidity data to the main control module; The main control module is used to compare the real-time humidity data with a preset humidity threshold. If the real-time humidity data is not less than the preset humidity threshold, the PTC heating element is turned off.

2. The system according to claim 1, characterized in that, The support module is also used to fix the humidity sensing module to the outer surface of the aluminum tube in the PTC heating element and to be located at the air outlet or air return outlet of the PTC heating element.

3. The system according to claim 1, characterized in that, The support module includes a bracket and an air guide assembly. The air guide assembly is used to form a stable airflow path between the aluminum tube and the heat sink. The bracket is used to fix the humidity sensing module on the stable airflow path.

4. The system according to claim 1, characterized in that, The humidity sensing module includes a humidity sensor and a ventilation component. The ventilation component is used to form a return air path, and the humidity sensor is disposed on the return air path.

5. The system according to claim 4, characterized in that, The humidity sensing module also includes an optocoupler component, through which the humidity sensor sends the collected real-time humidity data to the main control module.

6. The system according to claim 4 or 5, characterized in that, The humidity sensor includes the SHT35 model humidity sensor.

7. The system according to claim 1, characterized in that, The preset humidity threshold is 60%.

8. A method for safety testing of a PTC heating element, characterized in that, The method, applied to the PTC heating element safety detection system as described in any one of claims 1-7, comprises: Obtain real-time humidity data around the aluminum tube; The real-time humidity data is compared with a preset humidity threshold. If the real-time humidity data is not less than the preset humidity threshold, a PTC heating element shutdown signal is output.

9. The method according to claim 8, characterized in that, The step of comparing the real-time humidity data with a preset humidity threshold includes: The real-time humidity data is filtered to obtain effective real-time humidity data; The effective real-time humidity data is compared with a preset humidity threshold. The filtering process includes at least one of the following: moving average filtering, median filtering, threshold filtering, adaptive filtering, and data interpolation filtering.

10. A PTC heating element, characterized in that, It includes aluminum tubes, heat sinks, and a PTC heating element safety detection system as described in any one of claims 1-7.

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