CN212793492U

CN212793492U - Digital low-splashing gas shielded welding machine

Info

Publication number: CN212793492U
Application number: CN202020586152.5U
Authority: CN
Inventors: 陈良火; 毛桂香
Original assignee: Shanghai Megabice Welding Technology Co ltd
Current assignee: Shanghai Megabice Welding Technology Co ltd
Priority date: 2020-04-19
Filing date: 2020-04-19
Publication date: 2021-03-26
Anticipated expiration: 2030-04-19

Abstract

The utility model relates to a digital low-splashing gas shielded welding machine, which comprises a main circuit part and a control part, wherein the main circuit part comprises an inversion main loop and a chopper circuit, and the control part comprises a main control panel, a main drive plate, an auxiliary power circuit and a robot communication plate; the main control board is respectively connected with the control panel, the main drive board, the auxiliary power circuit, the inversion main loop and the robot communication board, the input end of the inversion main loop is connected with three-phase alternating current through a power switch, the positive output end of the inversion main loop is connected with the input end of the chopper circuit, and the output end of the main drive board is respectively connected with the inversion main loop and the chopper circuit. The utility model discloses a full digital control, operating panel is succinct clear, and welding performance has all reached fine effect with the control that splashes to be furnished with and robot communication interface, conveniently realize robot automated production.

Description

Digital low-splashing gas shielded welding machine

Technical Field

The utility model relates to a gas shielded welding machine technical field especially relates to a digital low gas shielded welding machine that splashes.

Background

The transition mode of the gas shielded welding machine (hereinafter referred to as a gas shielded welding machine) on the market is mainly short circuit transition, and the main characteristics of the transition are short circuit time and short circuit frequency. The short circuit transition is generated under the conditions of thin welding wires, low voltage and small current, the factor influencing the stability of the short circuit transition is mainly voltage, and when the voltage is generally about 18-21V, the short circuit time is longer and the process is more stable. The welding current and the wire diameter, i.e. the current density of the wire, also have a great influence on the short-circuit transition.

When the gas shielded welding machine is used for welding, the welding wire can generate great splashing in the process of explosion breaking, so that the forming of a welding seam is influenced, the splashed objects after welding need to be cleaned and polished for the second time, and the secondary processing cost is increased. Although some gas shielded welding machine technologies for reducing welding spatter exist in the market, the cost is high due to the extremely complex designed circuit, and only a few user units can buy the gas shielded welding machine, so that the gas shielded welding machine is not beneficial to being widely popularized.

With the continuous increase of labor cost, the control requirement on the welding spatter of the gas shielded welding machine is higher and higher, and how to reduce the spatter of the gas shielded welding machine by using a low-cost scheme becomes a technical problem to be solved by various welding machine manufacturers.

SUMMERY OF THE UTILITY MODEL

Therefore, a digital low-spatter gas shield welding machine is needed to be provided for solving the problems of large spatter, complex design circuit and the like of the traditional gas shield welding machine.

The utility model discloses a digital low gas shield welding machine that splashes, including main circuit part and control part, main circuit part includes contravariant main loop 105 and chopper circuit 106, the control part includes main control panel 100, control panel 101, robot communication board 102, main drive board 103 and auxiliary power supply circuit 107; the main control 100 board is connected with the control panel 101, the main drive board 103, the auxiliary power circuit 107, the inversion main loop 105 and the robot communication board 102, the input end of the inversion main loop 105 is connected with three-phase alternating current through a power switch, the positive output end of the inversion main loop 105 is connected with the input end of the chopper circuit 106, and the output end of the main drive board 103 is connected with the inversion main loop 105 and the chopper circuit 106.

In one embodiment, an input terminal of the auxiliary power circuit 107 is connected to an output terminal of the EMC absorption board 109, and output terminals of the auxiliary power circuit 107 are connected to input terminals of the main control board 100 and the main drive board 103, respectively.

In one embodiment, the inverter main loop comprises a rectifying and filtering circuit, an IGBT inverter circuit and a secondary rectifying circuit;

the rectifying and filtering circuit comprises an EMC absorption plate 109, a three-phase rectifier bridge D1 and a capacitor (C1-C4); the input end of the EMC absorption plate 109 is connected with three-phase alternating current, the other output end of the EMC absorption plate 109 is connected with the input end of a three-phase rectifier bridge D1, and the capacitors (C1-C4) are connected in parallel and then connected with the positive electrode and the negative electrode of the three-phase rectifier bridge D1;

the IGBT inverter circuit comprises IGBTs (T1-T4) and a first absorption circuit, wherein the E pole of the IGBT T1 is connected with the C pole of the IGBT T2 in series and then connected with the output end of the rectifying and filtering circuit, the E pole of the IGBT T3 is connected with the C pole of the IGBT T4 in series and then connected with the output end of the rectifying and filtering circuit, and the first absorption circuit comprises resistors (RX 1-RX 4) and capacitors (CX 1-CX 4);

the secondary rectifying circuit comprises a main transformer B1, a second absorption circuit and a rectifying tube (D2, D3), wherein the cathode of the rectifying tube D2 is connected with the cathode of the rectifying tube D3; one end of the primary transformer B1 is connected to the intermediate node of the capacitor CX3 and the capacitor CX4, and the other end of the primary transformer B1 is connected with the current transformer IFB through the capacitor C6; one end of the secondary side of the transformer B1 is connected with the anode of the rectifier tube D2, and the other end is connected with the anode of the rectifier tube D3; the second absorption circuit comprises resistors (RX 5-RX 12) and capacitors (CX 5-CX 8).

In one embodiment, the chopper circuit 106 includes a chopper switch circuit, a freewheeling circuit, and a chopper absorption plate 104;

wherein the chopping switch circuit comprises a chopping switch IGBT T5; the follow current circuit comprises a follow current resistor R2, and the follow current resistor R2 is connected in parallel with the C pole and the E pole of the chopping switch IGBT T5; the chopper absorption plate 104 is connected in parallel with the freewheel resistor R2.

In one embodiment, the main control board 100 includes a wire feeder and a gas valve control module, a current and voltage feedback module, a single chip, and a robot control module;

the wire feeder and the air valve control module are connected with an external wire feeder through a socket J3 of the main control board 100, and the current and voltage feedback module is connected with an external Hall sensor through a socket J8 of the main control board 100; the single chip microcomputer comprises a main single chip microcomputer and a chopping single chip microcomputer, and a first PWM signal output by the main single chip microcomputer is output to the main driving board 103 through a socket J13 of the main control board 100; a second PWM signal output by the chopping singlechip is output to the main drive board 103 through a socket J17 of the main control board 100; the robot control module comprises a switching value control unit and an analog value control unit, the switching value control unit is connected with the robot communication board 102 through a socket J10 of the main control board 100, and the analog value control unit is connected with the robot communication board 102 through a socket J15 of the main control board (100).

In one embodiment, the main control board 100 further includes a protection function module, where the protection function module includes a temperature protection circuit, an overcurrent protection circuit, and an overvoltage and undervoltage protection circuit; one path of the temperature protection circuit is externally connected with a temperature switch RT2 through a socket J14 of the main control board 100, and the other path of the temperature protection circuit is externally connected with a temperature switch (RT1) through a socket J15 of the main control board 100; the overcurrent protection circuit is externally connected with a current transformer IFB on the primary side of a transformer B1 of the inversion main circuit 105 through a socket (J12) of the main control board (100); the overvoltage and undervoltage protection circuit is connected with the output end of a three-phase rectifier bridge D1 of the rectifier filter circuit through a socket J6 of the main control board 100.

In one embodiment, the output terminals of the main driving board 103 are respectively connected to the G1 pole and the E1 pole of the IGBT T1, the G2 pole and the E2 pole of the IGBT T2, the G3 pole and the E3 pole of the IGBT T3, and the G4 pole and the E4 pole of the IGBT T4 of the inverter main circuit 105.

In one embodiment, the output terminal of the main driving board 103 is connected to a chopping switch IGBT T5 of the chopper circuit 106.

In one embodiment, the robotic communication board 102 is external to the robotic control cabinet 108.

In one embodiment, the main control board is externally connected to the hall sensor and the + and-poles of the main circuit portion, respectively.

Gas shield welding machine adopts full digital control, and operating panel is succinct clear, and welding performance and the control that splashes have all reached fine effect to be furnished with and robot communication interface, conveniently realize robot automated production.

Drawings

FIG. 1 is a circuit diagram of a gas shielded welding machine in one embodiment.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

It will be understood that, as used herein, the terms "first," "second," and the like may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, a first diode may be referred to as a second diode, and similarly, a second diode may be referred to as a first diode, without departing from the scope of the present application.

Gas shield welding machine, including main circuit part and control section. The main circuit part comprises an inverter main circuit 105 and a chopper circuit 106, and the control part comprises a main control board 100, a control panel 101, a main drive board 103, an auxiliary power supply circuit 107 and a robot communication board 102. The main control board 100 is respectively connected to the control panel 101, the main drive board 103, the auxiliary power circuit 107, the inversion main circuit 105 and the robot communication board 102, an input end of the inversion main circuit 105 is connected to a three-phase alternating current through a power switch, an anode output end of the inversion main circuit 105 is connected to an input end of the chopper circuit 106, an output end of the main drive board 103 is respectively connected to the inversion main circuit 105 and the chopper circuit 106, an input end of the auxiliary power circuit 107 is connected to an output end of the EMC absorption board 109, and the auxiliary power circuit 107 is respectively connected to the main control board 100 and the main drive board 103.

FIG. 1 is a circuit diagram of a gas shielded welding machine in one embodiment, as shown. A digital low-spatter gas shield welding machine comprises a main circuit part and a control part. Wherein, the control part comprises a main control panel 100, a control panel 101, a robot communication board 102, a main drive board 103 and an auxiliary power circuit 107; the main circuit portion includes an inverter main circuit 105 and a chopper circuit 106.

In one embodiment, socket J1 of control panel 101 connects with socket J7 of main control panel 100. The control panel 101 includes a manual operation interface and a display interface. The manual operation interface consists of keys and an adjusting encoder; the display interface consists of an indicator light and a digital tube.

The low spatter, welding mode, welding material type, diameter of welding wire, control mode and entering setting of the secondary menu of the welding machine can be completed through the manual operation interface. In addition, indications of the function of the welder, such as current and voltage displays, may be displayed by the display interface described above.

In one embodiment, the main control panel 100 includes a wire feeder and a valve control module, a current and voltage feedback module, a single chip, a robot control module, and a protection function module. These modules are explained below.

The wire feeder and the gas valve control module are connected with an external wire feeder through a socket J3 of the main control board 100, and the wire feeder comprises a wire feeding motor, a gas valve, current and voltage regulation during manual welding, a welding gun switch and the like.

The current and voltage feedback module is connected with an external Hall sensor through a socket J8 of the main control board 100. Wherein, the current feedback signal is collected by a Hall sensor; the voltage feedback signal is externally output from a socket J5 of the main control board 100, and is collected by a positive pole and a negative pole. The collected current and voltage feedback signals are respectively input into a single chip microcomputer after logical operation, and the single chip microcomputer controls the molten drop transition and the arc characteristics during welding.

The single chip microcomputer comprises a main single chip microcomputer and a chopping single chip microcomputer, wherein 4 paths of first PWM (pulse width modulation, hereinafter referred to as PWM) signals output by the main single chip microcomputer are output to a socket J2 of the main driving board 103 through a socket J13 of the main control board 100. The 1-path second PWM signal output by the chopper singlechip is output to a socket J3 of the main drive board 103 through a socket J17 of the main control board 100.

The robot control module comprises a switching value control unit and an analog value control unit. The switching value control unit is connected with a socket J5 of the robot communication board 102 through a socket J10 of the main control board 100; the analog quantity control unit is connected with the socket J3 of the robot communication board 102 through the socket J15 of the main control board 100, and the analog quantity control unit is used for controlling welding current and voltage.

The protection function module comprises a temperature protection circuit, an overcurrent protection circuit and an overvoltage and undervoltage protection circuit. Wherein, the temperature protection circuit includes two way temperature protection: one way is externally connected with a temperature switch RT2 through a socket J14 of the main control board 100, the temperature switch RT2 is used for detecting the working temperature of a chopping switch IGBT (insulated gate bipolar transistor, hereinafter abbreviated as 'IGBT') T5 of the chopping circuit 106, when the working temperature exceeds the preset temperature, the second PWM signal output is immediately turned off, and the circuit enters a protection state; the other path is externally connected with a temperature switch RT1 through a socket J15 of the main control board 100, the temperature switch RT1 is used for detecting the working temperature of an IGBT (insulated gate bipolar transistor) tube (T1-T4) of the inversion main loop 105, when the working temperature exceeds a preset temperature, the first PWM signal output is immediately turned off, and the circuit enters a protection state.

The overcurrent protection circuit is externally connected with a current transformer IFB on the primary side of a transformer B1 of the inversion main circuit 105 through a socket J12 of the main control board 100, the current transformer IFB is used for detecting the primary side current of the inversion main circuit 105, and when the primary side current changes, the main first PWM signal is automatically adjusted through the single chip microcomputer to compensate; if the primary side current exceeds the preset peak value, the inversion main loop 105 is proved to be abnormal, the first PWM signal output needs to be immediately turned off, and the current enters a protection state.

The overvoltage and undervoltage protection circuit is connected with the output end of a three-phase rectifier bridge D1 of the rectifier and filter circuit through a socket J6 of the main control board 100. The overvoltage and undervoltage protection circuit detects the voltage and waveform of the direct-current bus rectified by the three-phase rectifier bridge D1, and when the voltage and waveform of the direct-current bus change, the single chip microcomputer automatically adjusts the first PWM signal for compensation; if the voltage of the direct current bus exceeds the preset value, the inversion main circuit 105 is proved to be abnormal, the first PWM signal output needs to be immediately turned off, and the circuit enters a protection state.

In one embodiment, the input terminal of the auxiliary power supply circuit 107 is connected to the socket J2 of the EMC absorption board 109, and the auxiliary power supply circuit 107 step-down outputs voltages of 19V, 9V, and 22V with the ac power of 380V through the transformer. The auxiliary power circuit 107 is connected to the socket J1 of the main drive board 103 to provide dual 19V power to the main drive board 103.

The auxiliary power supply circuit 107 is connected to the socket J1, the socket J2, and the socket J9 of the main control board 100, respectively. The auxiliary power supply circuit 107 inputs power through a socket J2 of the main control board 100 to provide double 19V power for the control part of the main control board 100; the auxiliary power circuit 107 inputs power through a socket J1 of the main control board 100 to provide double 22V power for the wire feeder and the air valve control; the auxiliary power supply circuit 107 inputs power through a socket J9 of the main control board 100 to provide 9V power for the overvoltage and undervoltage protection circuit.

In one embodiment, the output terminals of the main drive board 103 are connected to the G1 and E1 poles of the IGBT T1, the G2 and E2 poles of the IGBT T2, the G3 and E3 poles of the IGBT T3, the G4 and E4 poles of the IGBT T4, and the G5 and E5 poles of the chopper switch IGBT T5, respectively, of the inverter main circuit 105.

The 4 paths of first PWM signals output by the main single chip microcomputer are output through a socket J13 of the main control board 100 and input through a socket J2 of the main drive board 103, are pushed by the PWM signals of the main drive board 103, drive a transformer to generate negative voltage signals, and are driven by an optical coupler to be isolated, and are respectively output to G1 and E1 of IGBT T1, G2 and E2 of IGBT T2, G3 and E3 of IGBT T3, and G4 and E4 of IGBT T4 to control IGBTs (T1-T4) to realize an inversion function. The 1-path second PWM signal output by the chopper single chip microcomputer is output through a socket J17 of the main control board 100, is input through a socket J3 of the main drive board 103, and is output to G5 and E5 of a chopper switch IGBT T5 through the main drive board 103.

In one embodiment, the socket J5 of the robot communication board 102 is connected to the socket J10 of the main control board 100, the socket J4 of the robot communication board 102 is connected to the socket J3 of the main control board 100, and the robot communication board socket J3 is connected to the J15 of the main control board 100. The socket J1 and the socket J2 of the robot communication board 102 are both connected to the external robot control cabinet 108.

The 4 groups of input switching values of the robot control cabinet 108 are input through a socket J1 of the robot communication board 102, the 4 groups of input switching values respectively control a wire detection switch, a gas detection switch, an arc striking switch and a wire withdrawing switch, and the 4 groups of input switching values are isolated through optical couplers of the robot communication board 102 and are connected to a socket J10 of the main control board 100 through a socket J5 of the robot communication board 102. The 1 group of output switching values of the robot communication board 102 outputs a control arc striking success signal through the socket J1 thereof.

The 2-channel analog quantity of the robot communication board 102 controls functions such as current and voltage regulation, the socket J2 of the robot communication board 102 is connected to the robot control cabinet 108, and the socket J3 of the robot communication board 102 outputs and is connected to the socket J15 of the main control board 100 through optical coupling isolation of the robot communication board 102, so that welding current and voltage can be controlled. Because the utility model discloses the robot communication board 102 has been add, consequently the utility model discloses can with the industrial robot communication, realize the automatic welding of robot.

In one embodiment, the inverting main loop 105 includes a rectifying and filtering circuit, an IGBT inverting circuit, and a secondary rectifying circuit.

The rectifying and filtering circuit comprises an EMC absorption plate 109, a three-phase rectifier bridge D1 and a capacitor (C1-C4). The EMC absorber plate 109 is connected via a supply switch K to a 380V three-phase alternating current (U, V, W), the output of which is connected to the input of a three-phase rectifier bridge D1. The capacitors (C1-C4) are connected in parallel and then connected with the positive electrode and the negative electrode of the three-phase rectifier bridge D1. The three-phase rectifier bridge D1 rectifies the input three-phase alternating current, filters the rectified three-phase alternating current into direct current power through capacitors (C1-C4) and outputs the direct current power.

According to the requirement of an actual circuit, the rectifying and filtering circuit can further comprise a resistor R1 connected with the capacitor C1 in parallel, and can also comprise capacitors C5 connected with the capacitors (C1-C4) in parallel.

The IGBT inverter circuit comprises IGBTs (T1-T4) and a first absorption circuit. The E pole of the IGBT T1 is connected with the C pole of the IGBT T2 in series and then connected with the output end of the rectifying and filtering circuit. The E pole of the IGBT T3 is connected with the C pole of the IGBT T4 in series and then connected with the output end of the rectifying and filtering circuit.

The first absorption circuit includes resistors (RX 1-RX 4) and capacitors (CX 1-CX 4). The resistor RX1 is connected in series with the capacitor CX1, the capacitor CX2 and the resistor RX2 and then connected with the C pole of the IGBT T1 and the E pole of the IGBT T2; the resistor RX3 is connected in series with the capacitor CX3, the capacitor CX4 and the resistor RX4, and then connected to the C pole of the IGBT T3 and the E pole of the IGBT T4.

The secondary rectification circuit comprises a main transformer B1, a second absorption circuit and a rectifying tube (D2, D3). The cathode of the rectifier tube D2 is connected with the cathode of the rectifier tube D3; one end of the primary transformer B1 is connected to the intermediate node of the capacitor CX3 and the capacitor CX4, and the other end is connected with the current transformer IFB through the capacitor C6; the secondary side of the transformer B1 has one end connected to the anode of the rectifier D2 and the other end connected to the anode of the rectifier D3. After rectification by the secondary rectification circuit, the negative output end of the power supply is output through the reactor L1, and the positive output end of the power supply is connected with the input end of the chopper circuit 106.

From this, it is known that the first absorption circuit for the IGBTs (T1 to T4) is composed of the resistors (RX1 to RX4) and the capacitors (CX1 to CX 4); and the second absorption circuit of the rectifier tubes (D2 and D3) is composed of resistors (RX 5-RX 12) and capacitors (CX 5-CX 8).

In one embodiment, chopper circuit 106 includes a chopper switch circuit, a freewheeling circuit, and a chopper absorption plate 104. The chopper switch circuit includes a chopper switch IGBT T5, and is driven by chopping to control on and off of the chopper IGBT T5. The positive electrode of the power supply rectified by the secondary rectifying circuit is connected with the C electrode of the chopping switch IGBT T5 and is output to the positive electrode interface of the welding machine through the E electrode of the chopping switch IGBT T5.

The follow current circuit comprises a follow current resistor R2, the follow current resistor R2 is connected in parallel with the C pole and the E pole of the chopper switch IGBT T5, and when the chopper switch IGBT T5 is turned off, welding current is output through the follow current resistor R2.

The chopper absorption plate 104 is used for absorbing spike voltage of the chopper switch IGBT T5 during switching.

In one embodiment, chopper absorption plate 104 includes a diode, a resistor R, and a capacitor C. One end of the capacitor C is connected with the cathode of the diode D, the other end of the capacitor C is connected with the E pole of the chopper switch IGBT T5, and the resistor R is connected with the capacitor C in parallel. Of course, the chopper absorption plate 104 may be formed of other circuits, and the present invention is not limited thereto.

Because the chopper circuit is additionally arranged on the main circuit part of the utility model, the main circuit is prevented from being too complex, the internal structure of the welding machine is simplified, the production cost is greatly reduced, and the production efficiency is improved; and the control circuit part only adopts circuit boards such as a control panel, a main drive board, a robot communication board and the like, thereby greatly reducing the number of the circuit boards.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A digital low-spatter gas shield welding machine comprises a main circuit part and a control part, and is characterized in that the main circuit part comprises an inverter main circuit (105) and a chopper circuit (106), and the control part comprises a main control board (100), a control panel (101), a robot communication board (102), a main drive board (103) and an auxiliary power circuit (107); the main control board (100) is respectively connected with the control panel (101), the main drive board (103), the auxiliary power circuit (107), the inversion main loop (105) and the robot communication board (102), the input end of the inversion main loop (105) is connected with three-phase alternating current through a power switch, the positive output end of the inversion main loop (105) is connected with the input end of the chopper circuit (106), and the output end of the main drive board (103) is respectively connected with the inversion main loop (105) and the chopper circuit (106).

2. The digital low spatter gas shield welding machine according to claim 1, wherein an input terminal of said auxiliary power circuit (107) is connected to an output terminal of an EMC absorber board (109), and an output terminal of said auxiliary power circuit (107) is connected to input terminals of said main control board (100) and said main driving board (103), respectively.

3. The digital low spatter gas shield welding machine according to claim 1 or 2, wherein said inverter main circuit comprises a rectifier filter circuit, an IGBT inverter circuit, and a secondary rectifier circuit;

the rectifying and filtering circuit comprises an EMC absorption plate (109), a three-phase rectifier bridge D1 and a capacitor C1C 2C 3C 4; the input end of the EMC absorption plate (109) is connected with three-phase alternating current, the other output end of the EMC absorption plate (109) is connected with the input end of a three-phase rectifier bridge D1, and the capacitor C1C 2C 3C 4 is connected in parallel and then connected with the positive pole and the negative pole of the three-phase rectifier bridge D1;

the IGBT inverter circuit comprises an IGBT T1T 2T 3T 4 and a first absorption circuit, wherein the E pole of the IGBT T1 is connected with the C pole of the IGBT T2 in series and then connected with the output end of the rectifying and filtering circuit, the E pole of the IGBT T3 is connected with the C pole of the IGBT T4 in series and then connected with the output end of the rectifying and filtering circuit, and the first absorption circuit comprises a resistor RX1 RX2 RX3 RX4 and a capacitor CX1 CX2 CX3 CX 4;

the secondary rectifying circuit comprises a main transformer B1, a second absorption circuit and a rectifying tube D2D 3, wherein the cathode of the rectifying tube D2 is connected with the cathode of the rectifying tube D3; one end of the primary transformer B1 is connected to the intermediate node of the capacitor CX3 and the capacitor CX4, and the other end of the primary transformer B1 is connected with the current transformer IFB through the capacitor C6; one end of the secondary side of the transformer B1 is connected with the anode of the rectifier tube D2, and the other end is connected with the anode of the rectifier tube D3; the second absorption circuit comprises a resistor RX5 RX6 RX7 RX8 RX9 RX10 RX11 RX12 and a capacitor CX5 CX6 CX7 CX 8.

4. The digital low spatter gas shield welder according to claim 3, wherein said chopper circuit (106) comprises a chopper switching circuit, a freewheel circuit and a chopper absorption plate (104);

wherein the chopping switch circuit comprises a chopping switch IGBT T5; the follow current circuit comprises a follow current resistor R2, and the follow current resistor R2 is connected in parallel with the C pole and the E pole of the chopping switch IGBT T5; the chopper absorption plate (104) is connected in parallel with the freewheel resistor R2.

5. The digital low spatter gas shield welding machine according to claim 4, wherein said main control board (100) comprises a wire feeder and a gas valve control module, a current and voltage feedback module, a single chip microcomputer and a robot control module;

the wire feeder and the air valve control module are connected with an external wire feeder through a socket J3 of the main control board (100), and the current and voltage feedback module is connected with an external Hall sensor through a socket J8 of the main control board (100); the single chip microcomputer comprises a main single chip microcomputer and a chopping single chip microcomputer, and a first PWM signal output by the main single chip microcomputer is output to the main driving board (103) through a socket J13 of the main control board (100); a second PWM signal output by the chopping single chip microcomputer is output to the main driving plate (103) through a socket J17 of the main control plate (100); the robot control module comprises a switching value control unit and an analog value control unit, wherein the switching value control unit is connected with the robot communication board (102) through a socket J10 of the main control board (100), and the analog value control unit is connected with the robot communication board (102) through a socket J15 of the main control board (100).

6. The digital low spatter gas shield welding machine according to claim 5, wherein said main control board (100) further comprises a protection function module comprising a temperature protection circuit, an overcurrent protection circuit, and an overvoltage and undervoltage protection circuit; one path of the temperature protection circuit is externally connected with a temperature switch RT2 through a socket J14 of the main control board (100), and the other path of the temperature protection circuit is externally connected with a temperature switch RT1 through a socket J15 of the main control board (100); the overcurrent protection circuit is externally connected with a current transformer IFB on the primary side of a transformer B1 of the inversion main circuit (105) through a socket J12 of the main control board (100); the overvoltage and undervoltage protection circuit is connected with the output end of a three-phase rectifier bridge D1 of the rectifier filter circuit through a socket J6 of the main control board (100).

7. The digital low spatter gas shield welding machine according to claim 6, wherein the output terminals of said main driving board (103) are connected to the G1 and E1 poles of IGBT T1, the G2 and E2 poles of IGBT T2, the G3 and E3 poles of IGBT T3, and the G4 and E4 poles of IGBT T4 of said inverter main circuit (105), respectively.

8. The digital low spatter gas shield welder according to claim 6, wherein an output of said main drive plate (103) is connected to a chopper switch IGBT T5 of said chopper circuit (106).

9. The digital low spatter gas shield welding machine according to claim 1, wherein said robotic communication board (102) is externally connected to a robot control cabinet (108).

10. The digital low spatter gas shield welding machine as defined in claim 1, wherein said main control board is externally connected to a hall sensor and a "+," pole of said main circuit portion, respectively.