| 摘要 |
PURPOSE:To accurately detect and measure the resistance or voltage between electrode chips by disusing the lead wire for measuring voltage between electrodes for the electrode chip, by finding a voltage displacement factor and current displacement factor, by taking the resistance value between the electrode chips by multiplying this difference by the reference resistance value and by performing adaptive control with repeating this measurement extending over all electrifying period. CONSTITUTION:An arc ignition circuit 11 performs the constant current control which adjusts an ignition phase angle to a thyristor 8 by finding the variation in the welding current. A division circuit 14 finds a power source voltage displacement factor by detecting the welding power source voltage. A division circuit 16 finds the welding current displacement factor by dividing the welding current by the reference current value by detecting it. A substraction circuit 17 finds the resistance value between the electrode chips by substracting the power source voltage displacement factor fed from the division circuit 14 from the circuit 16. A multiplication the resistance displacement factor between electrode chips by the reference resistance value. The arc ignition circuit 11 monitors the resistance between electrode chips fed from the multiplication circuit 18 with performing the constant current control and performs the adaptive control by controlling the welding current and/or welding time according to the prescribed algorithm from the propulsion thereof.
|
