A detection device for cold-proof heating function of a heating rod for a dryer

Abstract

The application discloses a kind of detection devices of heating rod cold-proof heating function for dryer, by power input port, heating rod test port, detection circuit, isolation circuit, state indicating circuit several parts constitute.Power input port provides power, detection circuit receives electrical signal from heating rod, isolation circuit converts detection signal into safe, controllable switch signal, and state indicating circuit outputs visual state information.The device should break through the mode of traditional single detection, by integrated design, multiple heating rods can be accessed simultaneously, with automated detection mechanism and intuitive result display, so that the inspector can complete the function judgment of multiple heating rods in a short time.

Description

Technical Field

[0001] This invention relates to the field of testing devices, and more specifically to a testing device for the cold-proof heating function of a heating rod for a dryer. Background Technology

[0002] Currently, the most common method for testing the cold-proof heating function of heating rods used in dryers is to use a multimeter. Operators determine the quality of the heating rod by reading the multimeter readings. However, this method has significant limitations: First, the existing testing method is cumbersome, and the single-rod testing model leads to low efficiency, making it difficult to meet the needs of batch testing. Second, due to the lack of a systematic batch testing mechanism, some components are easily overlooked, posing a risk of missed detection and affecting the overall integrity of the test. Third, the tested components themselves have poor consistency and large resistance deviations; relying solely on traditional numerical readings can easily lead to misjudgments due to numerical fluctuations, reducing the accuracy of the test results. Fourth, traditional testing methods require a certain level of operator skill, and differences in operator proficiency may further affect the stability of the test results.

[0003] Therefore, it is particularly necessary to develop a device that can quickly and conveniently perform batch testing of the cold-proof heating function of heating rods. Summary of the Invention

[0004] Based on the above problems, this invention proposes a testing device for the cold-proof heating function of heating rods used in dryers. Through integrated design, integrated batch testing design, and simplified operation process, it achieves efficient, comprehensive, accurate, and easy-to-operate testing of the cold-proof heating function of heating rods.

[0005] Technical solution:

[0006] A device for detecting the cold-proof heating function of a heating rod for a dryer includes:

[0007] The power input port is used to connect an external DC power supply and provide the operating voltage for the device.

[0008] The heating rod test port is used to connect the heating rod under test, so that the temperature sensing element of the heating rod can be placed in an external environmental chamber.

[0009] The detection circuit includes a voltage divider module and a Zener diode VD1. The voltage divider module is electrically connected to the test port of the heating rod and the Zener diode VD1. When the heating rod under test is powered on, the voltage across the two ends is divided by the voltage divider module, which triggers the Zener diode VD1 to conduct.

[0010] The isolation circuit includes a photoelectric relay IC1. The input terminal of IC1 is connected to the detection circuit, and the output terminal is used to control the on / off state indication circuit. When the Zener diode VD1 is turned on, IC1 is activated.

[0011] A status indicator circuit is connected to the output terminal of IC1. When IC1 is activated, the status indicator circuit is turned on and generates an electrical pulse signal corresponding to the action of the heating rod.

[0012] Furthermore, the power input port is equipped with a reverse connection protection unit to prevent the power polarity from being reversed.

[0013] Furthermore, the reverse connection protection unit is a rectifier diode D1. The power input port is electrically connected to one end of the heating rod H1 under test through D1, and the other end of the heating rod H1 under test is connected to the voltage divider module of the detection circuit.

[0014] Furthermore, the voltage divider module in the detection circuit is formed by resistors R1 and R2 connected in parallel. One end of this voltage divider branch is connected to the node between the heating rod H1 under test and the rectifier diode D1, and the other end is grounded. The cathode of the Zener diode VD1 is connected to the common high potential terminal of resistors R1 and R2, and the anode is grounded.

[0015] Furthermore, the detection circuit also includes current-limiting resistors R3 and R4. The anode of the Zener diode VD1 is grounded through the current-limiting resistor R3. One end of the current-limiting resistor R4 is connected to the cathode of the Zener diode VD1, and the other end is connected to the isolation circuit.

[0016] Furthermore, the detection circuit also includes a capacitor C1, which is connected in parallel across resistors R1 and R2 to filter out high-frequency interference signals.

[0017] Furthermore, the photoelectric relay IC1 is an optocoupler type relay, with a light-emitting diode on its input side and a phototransistor or photothyristor structure on its output side, to achieve electrical isolation between the input and output.

[0018] Furthermore, the status indication circuit includes a current-limiting resistor R5 and a light-emitting diode LD1. One end of the current-limiting resistor R5 is connected to the power supply voltage, and the other end is connected to the anode of the light-emitting diode LD1. The cathode of the light-emitting diode LD1 is connected to the output terminal of IC1.

[0019] Furthermore, the electrical pulse signal generated by the status indication circuit can be connected to an external counter or microcontroller to accumulate the number of times the tested heating rod H1 operates.

[0020] The beneficial effects of this invention are:

[0021] (1) Simple and reliable circuit structure: The circuit consists of five modules. The simple design not only reduces potential hazards caused by overly complex circuits and improves the stability of device operation, but also provides great convenience for later maintenance and component replacement, reducing maintenance costs and time.

[0022] (2) High integration and portability: The device can be integrated into the electrical control box, which is not only small in size and saves space, but also has a high protection level and can adapt to different working environments. At the same time, its small size makes it easy to carry and can be flexibly applied to various detection scenarios.

[0023] (3) Interface design takes into account both convenience and protection: all external interfaces are connected by nylon waterproof connectors. This design facilitates the quick connection of external equipment and improves the ease of operation. On the other hand, it effectively ensures the overall protection level of the device, prevents water, dust and other impurities from entering, and extends the service life of the device.

[0024] (4) The modules are economical and practical: the components used are all mature products. These modules have stable performance and can ensure the detection accuracy and operation effect of the device. At the same time, the mature products are cheaper, which reduces the overall cost of the device. They are also easy to maintain and replace, which further improves the economy and practicality of the device.

[0025] (5) Reduced operational difficulty: All parts of the device are fully integrated into one unit. This highly integrated design greatly simplifies the operation process and significantly reduces the difficulty of operation. Even personnel who are not very familiar with the equipment can quickly get started after simple training. At the same time, the integrated structure avoids the operational risks of complex external wiring and scattered components, which greatly improves the safety during operation. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below.

[0027] Figure 1 This is a schematic diagram of the composition of an experimental apparatus according to an embodiment of the present invention;

[0028] Figure 2 This is a simplified test circuit according to an embodiment of the present invention. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the following detailed description, in conjunction with the accompanying drawings and embodiments, further illustrates the invention. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the invention.

[0030] This invention discloses a detection device for the cold-proof heating function of a heating rod used in a dryer, such as... Figure 1 As shown, the device consists of a power input port, a heating rod test port, a detection circuit, an isolation circuit, and a status indication circuit. The power input port provides power, the detection circuit receives electrical signals from the heating rod, the isolation circuit converts the detection signals into safe and controllable switching signals, and the status indication circuit outputs visual status information.

[0031] like Figure 2 As shown, a pulse generating and counting device for long-life operation experiments is provided, wherein,

[0032] Power input ports: Components E1 and D1 are power input ports, which are connected to the terminal block of the electrical control box. DC power input terminal E1 is used to provide DC 110V power to power the heating rod and the entire device. Rectifier diode D1 is for reverse connection protection to prevent the power input polarity from being reversed, which could cause damage to subsequent equipment.

[0033] Heating rod test port: H1 is the heating rod under test. The temperature sensing element of the heating rod is placed in the high and low temperature test chamber. The heating rod cable is connected to the internal device of the control box through the external cable clamp of the control box. When the circuit is on, H1 is heated; when it is off, heating stops. The voltage change at its two ends can reflect the working status.

[0034] The detection circuit consists of C1, R1, R2, R3, VD1, and R4. Resistors R1 and R2 are connected in parallel to form a voltage divider branch. One end of this voltage divider branch is connected to the node between the heating rod H1 under test and the rectifier diode D1, and the other end is grounded. Capacitor C1 is connected in parallel across resistors R1 and R2 to filter out high-frequency interference signals. The cathode of the Zener diode VD1 is connected to the common high-potential terminal of resistors R1 and R2, and the anode is grounded through the current-limiting resistor R3. One end of the current-limiting resistor R4 is connected to the cathode of the Zener diode VD1, and the other end is electrically connected to the positive terminal of the LED on the input side of the photoelectric relay IC1. The negative terminal of the LED on the input side of the photoelectric relay IC1 is grounded.

[0035] Its working principle is as follows: A DC 110V power supply E1 is connected to the detection circuit through an external heating rod under test. In the circuit, R1 and R2 are high-power metal film resistors with small resistance values, which play an important role in sampling. They are first connected in parallel, and then connected in series with the heating rod under test. This connection method can accurately detect the current flowing through the heating rod under test and convert the detected current signal into a voltage signal across the two resistors, providing a basis for subsequent signal processing.

[0036] C1 uses a 104 ceramic capacitor, whose main function is to filter out high-frequency voltage fluctuations that may occur across the sampling resistors (i.e., R1 and R2), ensuring the stability of the voltage signal and avoiding high-frequency interference from affecting the accuracy of the detection results.

[0037] R3 acts as a current-limiting resistor for VD1, effectively limiting the current flowing through VD1 and preventing thermal damage caused by excessive current, thus ensuring the normal operation of the Zener diode.

[0038] VD1 is a Zener diode that stabilizes the voltage fed back from the sampling resistor within a specified range, thereby preventing excessive surge voltage from causing permanent damage to IC1 and playing a crucial role in protecting the core components.

[0039] R4 is the current-limiting resistor of IC1. Its function is to limit the current flowing into the LED inside IC1, prevent overcurrent from damaging the LED, and further ensure the safe operation of the core components in the circuit.

[0040] Isolation circuit: IC1 is a photoelectric relay. Its input side is coupled to the aforementioned detection circuit, and its output side is used to control the on / off state indication circuit. Its insulation voltage can reach 2000VDC. It is used for logic judgment, converting the data collected by the detection circuit into logic levels.

[0041] Status indicator circuit: includes R5 and LD1. R5 is the current limiting resistor of LD1. It forms a switching circuit with IC1. When the front end detects feedback of the heating rod operation, the secondary side of IC1 will be pulled low and LD1 will be lit. LD1 is installed on the control box panel. At this time, the inspector can quickly judge the good or bad cold-proof heating function of the heating rod corresponding to the indicator by observing the status of the indicator.

[0042] The working principle of the entire system is as follows: by detecting the voltage or current change of the heating rod H1, it is determined whether it has completed an "action" (such as power on-off), and a pulse signal is triggered by the photoelectric relay, which simultaneously lights up the LED indicator, thereby realizing the counting of the number of times the heating rod has acted.

[0043] This application combines RC filtering with Zener diode threshold detection to reliably identify the operating status of the heating rod, and uses photoelectric relay IC1 to achieve electrical isolation, ensuring the stability and safety of the counting signal. It is suitable for application scenarios involving long-term, high-reliability operation count statistics.

[0044] When performing batch testing, simply select N items such as... Figure 2The unit circuits shown are connected in parallel to the power bus of the control box, and their status signals are centrally sent to a central processing or display unit. Each unit operates independently, generating and counting pulses for the connected heating rods. The control box serves as a centralized installation and wiring platform, and its interior can be designed to accommodate multiple units such as... Figure 2 The unit circuit shown is illustrated. The wiring terminals of the electrical control box provide a unified power distribution and signal aggregation point for these modules. In batch applications, this indicator circuit can be designed as a multi-channel display, for example, using multiple LEDs to indicate the status of each channel, or using digital tubes to cycle through and display the count data of each channel, thereby achieving centralized monitoring of batch test samples. Ten indicator lights can be installed on the door cover of the electrical control box, which can be used for quick and batch judgment of the heating rod's cold-proof and heat-dissipation functions.

[0045] This device should break through the traditional single-element testing mode. Through integrated design, it can simultaneously connect multiple heating rods. With the help of automated testing mechanisms and intuitive result display, inspectors can quickly assess the function of multiple heating rods. This not only significantly improves testing efficiency and reduces manpower and time costs, but also simplifies the operation process and reduces testing errors caused by human error, providing a more reliable and efficient solution for quality control of dryer heating rods.

[0046] Finally, it should be noted that the above descriptions 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 device for detecting the cold-proof heating function of a heating rod for a dryer, characterized in that, include: The power input port is used to connect an external DC power supply and provide the operating voltage for the device. The heating rod test port is used to connect the heating rod under test, so that the temperature sensing element of the heating rod can be placed in an external environmental chamber. The detection circuit includes a voltage divider module and a Zener diode VD1. The voltage divider module is electrically connected to the test port of the heating rod and the Zener diode VD1. When the heating rod under test is powered on, the voltage across the two ends is divided by the voltage divider module, which triggers the Zener diode VD1 to conduct. The isolation circuit includes a photoelectric relay IC1. The input terminal of IC1 is connected to the detection circuit, and the output terminal is used to control the on / off state indication circuit. When the Zener diode VD1 is turned on, IC1 is activated. A status indicator circuit is connected to the output terminal of IC1. When IC1 is activated, the status indicator circuit is turned on and generates an electrical pulse signal corresponding to the action of the heating rod.

2. The detection device according to claim 1, characterized in that, The power input port is equipped with a reverse connection protection unit to prevent the power polarity from being reversed.

3. The detection device according to claim 2, characterized in that, The reverse connection protection unit is a rectifier diode D1. The power input port is electrically connected to one end of the heating rod H1 under test through D1, and the other end of the heating rod H1 under test is connected to the voltage divider module of the detection circuit.

4. The detection device according to any one of claims 1-3, characterized in that, The voltage divider module in the detection circuit is formed by resistors R1 and R2 connected in parallel. One end of the voltage divider branch is connected to the node between the heating rod H1 under test and the rectifier diode D1, and the other end is grounded. The cathode of the Zener diode VD1 is connected to the common high potential terminal of resistors R1 and R2, and the anode is grounded.

5. The detection device according to claim 4, characterized in that, The detection circuit also includes current-limiting resistors R3 and R4. The anode of the Zener diode VD1 is grounded through the current-limiting resistor R3. One end of the current-limiting resistor R4 is connected to the cathode of the Zener diode VD1, and the other end is connected to the isolation circuit.

6. The detection device according to claim 4, characterized in that, The detection circuit also includes a capacitor C1, which is connected in parallel across resistors R1 and R2 to filter out high-frequency interference signals.

7. The detection device according to claim 1, characterized in that, The photoelectric relay IC1 is an optocoupler type relay, with a light-emitting diode on its input side and a phototransistor or photothyristor structure on its output side, achieving electrical isolation between the input and output.

8. The detection device according to claim 1, characterized in that, The status indication circuit includes a current-limiting resistor R5 and a light-emitting diode LD1. One end of the current-limiting resistor R5 is connected to the power supply voltage, and the other end is connected to the anode of the light-emitting diode LD1. The cathode of the light-emitting diode LD1 is connected to the output terminal of IC1.

9. The detection device according to claim 1, characterized in that, The electrical pulse signal generated by the status indication circuit is connected to an external counter or microcontroller to accumulate the number of times the tested heating rod H1 is activated.

10. The detection device according to claim 1, characterized in that, The detection device is integrated into the electrical control box, and all external interfaces are connected via nylon waterproof connectors.

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