摘要 |
Resistance welding device of the type comprising two welding electrodes (21, 31) that are displaceable in relation to one another and can clamp between them the sheet metal to be welded. One of said electrodes (31) is connected to driving means formed by a screw-nut mechanism (8, 9) operated by an electric motor (6), said driving means being connected to electronic control means (7) capable of controlling the force with which the electrodes (21, 31) clamp said sheet metal to be welded by controlling the supply current of the electric motor (6). The device of the invention is characterized in that said screw-nut mechanism transmitting the force of the motor (6) to the electrodes (21, 31) is highly efficient and reversible, and in that said electronic means (7) control the clamping force of said electrodes by a closed control loop using the value of the supply current passing through the electric motor (6). |