Intelligent high-frequency arc striking circuit

Abstract

The invention discloses an intelligent high-frequency arc striking circuit which comprises an MCU, a charging control circuit, a discharging control circuit and a high-frequency inductor. The MCU is used for sending a charging control signal and a discharging control signal; the charging control circuit is connected with the MCU and is used for receiving and processing the charging control signal; the discharge control circuit is connected with the MCU and is used for receiving and processing the discharge control signal; a terminal 1 of the high-frequency inductor is connected with the charging control circuit, a terminal 2 of the high-frequency inductor is connected with the discharging control circuit, and terminals 3 and 4 of the high-frequency inductor are connected with an output main loop of an external electric welding machine. According to the invention, the frequency and voltage control of the high-frequency and high-voltage arcing circuit can be adjusted, different working frequencies and working voltages can be selected according to different use conditions, high-frequency interference can be effectively reduced, and radiation damage to human bodies can be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of arc ignition circuits of argon arc welding machines, and in particular to an intelligent high-frequency arc ignition circuit. Background Art

[0002] In argon arc welding models, in order to improve work efficiency, the most common arc starting method is high-frequency and high-voltage arc starting. While high-frequency and high-voltage arc starting is highly efficient, it will introduce strong electromagnetic interference, disrupt surrounding electrical products, and cause strong interference to the argon arc welding machine itself. Summary of the invention

[0003] According to an embodiment of the present invention, there is provided an intelligent high-frequency arc ignition circuit, comprising: an MCU, a charging control circuit, a discharging control circuit and a high-frequency inductor; MCU is used to send charging control signals and discharging control signals; The charging control circuit is connected to the MCU and is used to receive and process the charging control signal; The discharge control circuit is connected to the MCU and is used to receive and process the discharge control signal; Terminal 1 of the high-frequency inductor is connected to a charging control circuit, terminal 2 of the high-frequency inductor is connected to a discharging control circuit, and terminals 3 and 4 of the high-frequency inductor are connected to an external electric welding machine output main circuit.

[0004] Furthermore, the charging control circuit includes: a boost control chip, a first resistor, a first MOS tube, a second resistor, a third resistor, a first capacitor, a boost transformer, a first diode and a second capacitor; Pin 1 of the boost control chip is connected to the MCU, pin 6 of the boost control chip is connected to one end of the first resistor, and pin 3 of the boost control chip is connected to one end of the second resistor; The other end of the first resistor is connected to the gate of the first MOS tube; The other end of the second resistor is connected to the source of the first MOS tube and one end of the third resistor; The other end of the third resistor is grounded; The drain of the first MOS tube is connected to the terminal 1 of the step-up transformer; After the terminal 2 of the step-up transformer is connected to the VCC port and grounded through the first capacitor, the terminal HV of the step-up transformer is connected to the positive electrode of the first diode; The cathode of the first diode is connected to terminal 1 of the high-frequency inductor and one end of the second capacitor; The other end of the second capacitor is connected to the terminal 3 of the step-up transformer and then grounded.

[0005] Furthermore, the charging control circuit further includes: a third capacitor, one end of the third capacitor is connected between the pin 3 of the boost control chip and one end of the second resistor, and the other end of the third capacitor is grounded.

[0006] Furthermore, the charging control circuit further comprises: a fourth resistor and a fourth capacitor; One end of the fourth resistor is connected to pin 8 of the boost control chip; One end of the fourth capacitor is connected to the pin 4 of the boost control chip and the other end of the fourth resistor, and the other end of the fourth capacitor is grounded.

[0007] Further, the discharge control circuit includes: a fifth resistor, a second MOS tube, a bidirectional breakdown diode, an isolation drive transformer, a sixth resistor, a second diode, a thyristor and a hardware protection circuit; One end of the fifth resistor is connected to the MCU; The gate of the second MOS tube is connected to the other end of the fifth resistor, the source of the second MOS tube is grounded, and the drain of the second MOS tube is connected to one end of the bidirectional breakdown diode and the terminal 2 of the isolation drive transformer; The terminal 1 of the isolation drive transformer is connected to one end of the bidirectional breakdown diode and then connected to the VCC port, the terminal 3 of the isolation drive transformer is connected to one end of the sixth resistor, and the terminal 4 of the isolation drive transformer is grounded; The other end of the sixth resistor is connected to the anode of the second diode; The cathode of the second diode is connected to the gate of the thyristor; The cathode of the thyristor is grounded, and the anode of the thyristor is connected to terminal 2 of the high-frequency inductor; The hardware protection circuit is connected to the gate and anode of the thyristor.

[0008] Furthermore, the hardware protection circuit includes: a voltage regulator tube and a seventh resistor; One end of the voltage regulator is connected to the anode of the thyristor; One end of the seventh resistor is connected to one end of the voltage regulator tube, and the other end of the seventh resistor is connected between the gate of the thyristor and the cathode of the second diode.

[0009] Furthermore, the discharge control circuit further includes: a third diode, the cathode of the third diode is connected between the sixth resistor and the second diode, and the other end of the third diode is grounded.

[0010] Furthermore, the discharge control circuit further comprises: an eighth resistor and a fifth capacitor; One end of the eighth resistor is connected between the gate of the thyristor and the cathode of the second diode, and the other end of the eighth resistor is grounded; One end of the fifth capacitor is connected between one end of the eighth resistor and the gate of the thyristor, and the other end of the fifth capacitor is grounded.

[0011] Furthermore, the discharge control circuit further includes: a ninth resistor, one end of the ninth resistor is connected between the other end of the fifth resistor and the gate of the second MOS tube, and the other end of the ninth resistor is connected to the source of the second MOS tube and then grounded.

[0012] According to an embodiment of the present invention, an intelligent high-frequency arc starting circuit can adjust the frequency and voltage control of the high-frequency and high-voltage arc starting circuit. Different operating frequencies and operating voltages can be selected for different usage conditions, which can effectively reduce high-frequency interference and reduce radiation damage to the human body.

[0013] It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the technology as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The figure is a circuit diagram of an intelligent high-frequency arc ignition circuit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0015] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings to further illustrate the present invention.

[0016] First, combine Figure 1 An intelligent high-frequency arc starting circuit according to an embodiment of the present invention is described, which is used for arc starting of argon arc welding and has a wide range of application scenarios.

[0017] like Figure 1 As shown, an intelligent high-frequency arc starting circuit according to an embodiment of the present invention comprises an MCU, a charging control circuit, a discharging control circuit and a high-frequency inductor TR2.

[0018] Specifically, Figure 1 As shown, the MCU is used to send a charging control signal and a discharging control signal.

[0019] Specifically, Figure 1As shown, the charging control circuit is connected to the MCU for receiving and processing the charging control signal. The charging control circuit includes: a boost control chip U1, a first resistor R1, a first MOS tube T1, a second resistor R2, a third resistor R3, a first capacitor C3, a boost transformer TR1, a first diode D1 and a second capacitor C4. Pin 1 of the boost control chip U1 is connected to the MCU, pin 6 of the boost control chip U1 is connected to one end of the first resistor R1, and pin 3 of the boost control chip U1 is connected to one end of the second resistor R2; the other end of the first resistor R1 is connected to the gate of the first MOS tube T1, and the first resistor R1 is used to limit the current flowing from the output pin of the boost control chip U1 to the first MOS tube T1, and also plays a certain impedance matching role, so that the output pin of the boost control chip U1 and the input stage (gate) of the first MOS tube T1 can work better together, ensure the effective transmission of the signal, and reduce the adverse effects such as signal reflection; the other end of the second resistor R2 is connected to the source of the first MOS tube T1 and one end of the third resistor R3; the other end of the third resistor R3 is grounded; the drain of the first MOS tube T1 is connected to the terminal 1 of the boost transformer TR1, and the first MOS tube T1 is used as a switching element. When the OUT pin of the boost control chip U1 outputs a high-level signal, the gate of the first MOS tube T1 is connected through the first resistor R1. -The source voltage is greater than its turn-on threshold voltage, and the first MOS transistor T1 is turned on; at this time, the power supply supplies power to the primary winding of the boost transformer TR1 through the first MOS transistor T1; when the OUT pin of the boost control chip U1 outputs a low-level signal, the gate-source voltage of the first MOS transistor T1 is lower than the turn-on threshold voltage, the first MOS transistor T1 is turned off, and stops supplying power to the boost transformer TR1; the first MOS transistor T1 can also control a larger current to pass through the boost transformer TR1 to achieve the conversion of electric energy, convert the input DC electric energy into high-frequency pulse electric energy, and provide an input signal for the subsequent boost transformer TR1, which is one of the key components for realizing the boost function; after the terminal 2 of the boost transformer TR1 is connected to the VCC port and grounded through the first capacitor C3, the terminal HV of the boost transformer TR1 is connected to the positive electrode of the first diode D1; the cathode of the first diode D1 is connected to the terminal 1 of the high-frequency inductor TR2 and one end of the second capacitor C4; the other end of the second capacitor C4 is connected to the terminal 3 of the boost transformer TR1 and then grounded.

[0020] Further, if Figure 1 As shown, the charging control circuit further includes: a third capacitor C2, one end of the third capacitor C2 is connected between pin 3 of the boost control chip U1 and one end of the second resistor R2, the other end of the third capacitor C2 is grounded, and the third capacitor C2 is used for filtering.

[0021] Further, if Figure 1As shown, the charging control circuit also includes: a fourth resistor R4 and a fourth capacitor C1; one end of the fourth resistor R4 is connected to pin 8 of the boost control chip U1; one end of the fourth capacitor C1 is connected to pin 4 of the boost control chip U1 and the other end of the fourth resistor R4, and the other end of the fourth capacitor C1 is grounded.

[0022] Specifically, Figure 1 As shown, the discharge control circuit is connected to the MCU and is used to receive and process the discharge control signal; the discharge control circuit includes: a fifth resistor R5, a second MOS tube Q1, a bidirectional breakdown diode Z2, an isolation drive transformer TR3, a sixth resistor R7, a second diode D3, a thyristor T2 and a hardware protection circuit. One end of the fifth resistor R5 is connected to the MCU, and is mainly used to limit the discharge signal current to prevent excessive current from directly impacting the gate of the second MOS tube Q1 and damaging the second MOS tube Q1. At the same time, it effectively transmits the discharge signal to the gate of the second MOS tube Q1 to control the on and off state of the second MOS tube Q1; the gate of the second MOS tube Q1 is connected to the other end of the fifth resistor R5, the source of the second MOS tube Q1 is grounded, the drain of the second MOS tube Q1 is connected to one end of the bidirectional breakdown diode Z2, and the terminal 2 of the isolation drive transformer TR3, and the on and off of the circuit is controlled according to the discharge control signal. When the discharge control signal turns on the second MOS tube Q1, it allows current to flow from the drain to the source, thereby realizing the conduction of the energy transmission path; the terminal 1 of the isolation drive transformer TR3 is connected to one end of the bidirectional breakdown diode Z2, and then to the VCC port, the terminal 3 of the isolation drive transformer TR3 is connected to one end of the sixth resistor R7, and the isolation drive transformer Terminal 4 of TR3 is grounded; the other end of the sixth resistor R7 is connected to the positive electrode of the second diode D3, which limits the current of the signal output from the isolation drive transformer TR3 to prevent excessive current from damaging the second diode D3 and subsequent components. At the same time, it also effectively transmits the signal transformed by the isolation drive transformer TR3 to the second diode D3 to ensure that the signal can be smoothly transmitted in the circuit; the cathode of the second diode D3 is connected to the gate of the thyristor T2; the cathode of the thyristor T2 is grounded, and the anode of the thyristor T2 is connected to the terminal 2 of the high-frequency inductor TR2. When the discharge current in the primary of the high-frequency inductor TR2 is lower than the threshold, the thyristor T2 will automatically turn off to ensure that it is discharged only once in a cycle and wait for the arrival of the next charging cycle; the hardware protection circuit is connected to the gate and anode of the thyristor T2.

[0023] Further, specifically, Figure 1As shown, the hardware protection circuit includes: a voltage regulator tube Z1 and a seventh resistor R8; one end of the voltage regulator tube Z1 is connected to the anode of the thyristor T2; one end of the seventh resistor R8 is connected to one end of the voltage regulator tube Z1, and the other end of the seventh resistor R8 is connected between the gate of the thyristor T2 and the cathode of the second diode D3. The hardware protection circuit is used to force T2 to turn on when the voltage on the capacitor exceeds the value of the voltage regulator tube Z1, to prevent the voltage from accumulating too high and damaging components when the MCU control fails.

[0024] Further, if Figure 1 As shown, the discharge control circuit further includes: a third diode D2, the cathode of the third diode D2 is connected between the sixth resistor R7 and the second diode D3, and the other end of the third diode D2 is grounded. The third diode D2 plays a clamping role. When an excessively high forward voltage spike appears in the circuit, such as a transient voltage generated during the switching process, the third diode D2 clamps the voltage at a lower level to protect the second diode D3 and other subsequent components from being damaged by excessive voltage.

[0025] Further, if Figure 1 As shown, the discharge control circuit further includes: an eighth resistor R9 and a fifth capacitor C5; one end of the eighth resistor R9 is connected between the gate of the thyristor T2 and the negative electrode of the second diode D3, and the other end of the eighth resistor R9 is grounded; one end of the fifth capacitor C5 is connected between one end of the eighth resistor R9 and the gate of the thyristor T2, and the other end of the fifth capacitor C5 is grounded. The eighth resistor R9 and the fifth capacitor C5 are used for anti-interference and filtering.

[0026] Further, if Figure 1 As shown, the discharge control circuit further includes: a ninth resistor R6, one end of the ninth resistor R6 is connected between the other end of the fifth resistor R5 and the gate of the second MOS tube Q1, and the other end of the ninth resistor R6 is connected to the source of the second MOS tube Q1 and then grounded. The ninth resistor R6 provides a discharge path between the gate and the source of the second MOS tube Q1, and when the gate signal disappears, the charge on the gate can be quickly discharged, so that the second MOS tube Q1 can be reliably cut off. In addition, it can also form a voltage divider circuit together with the fifth resistor R5, and adjust the voltage of the gate of the second MOS tube Q1 to a certain extent, ensuring that the second MOS tube Q1 can be turned on and off according to the expected voltage threshold.

[0027] Specifically, Figure 1 As shown, terminal 1 of the high-frequency inductor TR2 is connected to the charging control circuit, terminal 2 of the high-frequency inductor TR2 is connected to the discharging control circuit, and terminals 3 and 4 of the high-frequency inductor TR2 are connected to the external welding machine output main circuit.

[0028] The charging control signal is a set of pulse signals, which are sent by the microcontroller. The charging cycle (or frequency) is the frequency of the high frequency; The discharge control signal is given at a fixed interval after the charge control signal comes out, and the fixed time is determined by the desired high frequency strength.

[0029] Here are some examples: When we start the argon arc welding machine for the first time, the tungsten needle is cold. At this time, if we want to start the arc with a higher success rate, we need a stronger high-frequency performance. At this time, the frequency of the charging control signal can be set to 100Hz, that is, one cycle is 10ms. After charging for a period of time, the voltage on the second capacitor C4 continues to rise, and the discharge control signal is sent out at this time, for example, after charging for 25us; Discharging starts immediately. At this time, the voltage on the second capacitor C4 is about 1200V. After passing through the high-frequency inductor TR2, it is boosted again and provided to the main output circuit of the welding machine.

[0030] After the machine has been used for a short period of time, the temperature of the tungsten needle is already high. At this time, such a high arc striking voltage is not required to stabilize the arc striking. Then we can start discharging after charging for 15us. At this time, the voltage on the second capacitor C4 is about 750V.

[0031] In this way, we achieve different discharge voltages through time control.

[0032] When a different arc ignition frequency is required, it is sufficient to change the frequency of the charging control signal.

[0033] Above, refer to Figure 1 An intelligent high-frequency arc starting circuit according to an embodiment of the present invention is described, which can adjust the frequency and voltage control of the high-frequency and high-voltage arc starting circuit. Different operating frequencies and operating voltages are selected for different usage scenarios, which can effectively reduce high-frequency interference and reduce radiation damage to the human body.

[0034] It should be noted that, in this specification, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprises..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0035] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

[0036] Subsequently, each sub-region was binarized using the Otsu threshold method to distinguish the stained area from the background area. The morphological features were extracted by Canny edge detection, and the texture and color features were extracted by combining the gray-level co-occurrence matrix and color histogram to generate a multi-dimensional feature vector for each sub-region.

[0037] Finally, the optimized images were classified using the K-means clustering algorithm. The images were converted to Lab color space, the Euclidean distance of the pixels was calculated, and they were divided into three categories: weak positive, moderate positive, and strong positive, completing the classification analysis of the positive staining area.

[0038] The details are shown in Table 1 below: Table 1 Immunohistochemical staining image analysis table

[0039] By analyzing the data in the above table, it can be clearly seen that there is a certain positive correlation between the total number of pixels in the positive staining area and the staining intensity. As the sum of the number of weakly positive, moderately positive, and strongly positive pixels increases, the staining intensity also increases accordingly. For example, image 5 has a total number of positive pixels of 3853 and a staining intensity of 0.772, which is the image with the highest staining intensity in the table; in contrast, image 1 has a total number of positive pixels of 2458 and a staining intensity of 0.647.

[0040] In addition, from the distribution of weakly positive, moderately positive, and strongly positive pixel numbers, it can be seen that weakly positive pixels usually occupy most of the positive area, while strongly positive pixels are relatively few. This trend indicates that the staining intensity of most stained areas is relatively moderate or weak, while the proportion of strongly stained areas is relatively low. This is consistent with the common phenomenon that weakly positive areas are more common and strongly positive areas are relatively rare in immunohistochemical staining.

[0041] Through the immunohistochemical digital pathology image processing method of the present invention, not only can the image noise be accurately removed, but also the positive staining area can be effectively classified, and weak positive, medium positive and strong positive areas can be distinguished. This reflects the efficiency and accuracy of the present invention in automated pathology image processing, and provides a more objective and reliable basis for pathological diagnosis.

[0042] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. An intelligent high-frequency arc ignition circuit, characterized in that: Includes: MCU, charging control circuit, discharge control circuit and high-frequency inductor; The MCU is used to send a charging control signal and a discharging control signal; The charging control circuit is connected to the MCU and is used to receive and process the charging control signal; The discharge control circuit is connected to the MCU and is used to receive and process the discharge control signal; The terminal 1 of the high-frequency inductor is connected to the charging control circuit, the terminal 2 of the high-frequency inductor is connected to the discharging control circuit, and the terminals 3 and 4 of the high-frequency inductor are connected to the external welding machine output main circuit; The charging control circuit comprises: a boost control chip, a first resistor, a first MOS tube, a second resistor, a third resistor, a first capacitor, a boost transformer, a first diode and a second capacitor; Pin 1 of the boost control chip is connected to the MCU, pin 6 of the boost control chip is connected to one end of the first resistor, and pin 3 of the boost control chip is connected to one end of the second resistor; The other end of the first resistor is connected to the gate of the first MOS tube; The other end of the second resistor is connected to the source of the first MOS tube and one end of the third resistor; The other end of the third resistor is grounded; The drain of the first MOS tube is connected to the terminal 1 of the boost transformer; After the terminal 2 of the step-up transformer is connected to the VCC port and grounded through the first capacitor, the terminal HV of the step-up transformer is connected to the positive electrode of the first diode; The cathode of the first diode is connected to the terminal 1 of the high-frequency inductor and one end of the second capacitor; The other end of the second capacitor is connected to the terminal 3 of the step-up transformer and then grounded; The discharge control circuit comprises: a fifth resistor, a second MOS tube, a bidirectional breakdown diode, an isolation drive transformer, a sixth resistor, a second diode, a thyristor and a hardware protection circuit; One end of the fifth resistor is connected to the MCU; The gate of the second MOS transistor is connected to the other end of the fifth resistor, the source of the second MOS transistor is grounded, and the drain of the second MOS transistor is connected to one end of the bidirectional breakdown diode and the terminal 2 of the isolation drive transformer; The terminal 1 of the isolation drive transformer is connected to one end of the bidirectional breakdown diode and then connected to the VCC port, the terminal 3 of the isolation drive transformer is connected to one end of the sixth resistor, and the terminal 4 of the isolation drive transformer is grounded; The other end of the sixth resistor is connected to the anode of the second diode; The cathode of the second diode is connected to the gate of the thyristor; The cathode of the thyristor is grounded, and the anode of the thyristor is connected to the terminal 2 of the high-frequency inductor; The hardware protection circuit is connected to the gate and anode of the thyristor.

2. The intelligent high-frequency arc ignition circuit as claimed in claim 1, characterized in that: The charging control circuit further includes: a third capacitor, one end of the third capacitor is connected between the pin 3 of the boost control chip and one end of the second resistor, and the other end of the third capacitor is grounded.

3. The intelligent high-frequency arc ignition circuit as claimed in claim 1, characterized in that: The charging control circuit further comprises: a fourth resistor and a fourth capacitor; One end of the fourth resistor is connected to pin 8 of the boost control chip; One end of the fourth capacitor is connected to the pin 4 of the boost control chip and the other end of the fourth resistor, and the other end of the fourth capacitor is grounded.

4. The intelligent high-frequency arc ignition circuit as claimed in claim 1, characterized in that: The hardware protection circuit comprises: a voltage regulator tube and a seventh resistor; One end of the voltage regulator tube is connected to the anode of the thyristor; One end of the seventh resistor is connected to one end of the voltage regulator tube, and the other end of the seventh resistor is connected between the gate of the thyristor and the cathode of the second diode.

5. The intelligent high-frequency arc ignition circuit as claimed in claim 1, characterized in that: The discharge control circuit further includes: a third diode, wherein a cathode of the third diode is connected between the sixth resistor and the second diode, and the other end of the third diode is grounded.

6. The intelligent high-frequency arc ignition circuit according to claim 1, characterized in that: The discharge control circuit further comprises: an eighth resistor and a fifth capacitor; One end of the eighth resistor is connected between the gate of the thyristor and the cathode of the second diode, and the other end of the eighth resistor is grounded; One end of the fifth capacitor is connected between one end of the eighth resistor and the gate of the thyristor, and the other end of the fifth capacitor is grounded.

7. The intelligent high-frequency arc ignition circuit according to claim 1, characterized in that: The discharge control circuit further includes: a ninth resistor, one end of which is connected between the other end of the fifth resistor and the gate of the second MOS tube, and the other end of which is connected to the source of the second MOS tube and then grounded.

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