The medium frequency spot welding machine system consists of three parts: mechanical device, power supply device and control device. In order to adapt to the welding process requirements, medium frequency spot welding machine adopts a double-stroke rapid pressure transmission mechanism in the pressurizing mechanism (electrode holder). By changing the stroke control handle to change the opening of the welding pliers, it can be divided into wide open and small open to meet the welding operation requirements. . The normal state is the short span of the welding pliers. When the control button is switched to the “energized” position, the welding clamp clamps and pressurizes when the handle switch is pulled, and the current recovers to the short stroke after completing a welding cycle under the control of the control system. Open state.
2. Power supply device The main power circuit consists of a resistance welding transformer, a thyristor unit, a main power switch, and a welding circuit. At present, the welding equipment we use is single-phase power frequency AC resistance welding machine with power 200kVA and secondary output voltage 20V--40V. Due to the production of a variety of vehicle models, the welding pliers must weld high-strength steel plates and low-carbon steel plates. The welding pliers gun arm must transfer large mechanical forces and welding currents. Therefore, the strength, stiffness, and heat of the welding pliers must meet certain requirements. And to have good electrical conductivity and thermal conductivity, and at the same time require the welding clamp to use water cooling, so choose the welding clamp electrode arm can withstand 400kg pressure of the new welding clamp.
3. Control device
The control device mainly provides the signal control resistor intermediate frequency spot welder action to turn on and off the welding current, control the welding current value, and perform fault monitoring and processing.