Patent ID: 6072145
Filing Date: 2000-06-06
Classification: B23K

Abstract:
A spot welding apparatus comprising:a pressing axis having a variable mechanical impedance;a drive actuator connected to said pressing axis;a pair of welding electrodes connected to said pressing axis; andan impedance control device provided to said pressing axis constructed and arranged to control the mechanical impedance of said pressing axis, said impedance control device comprising:a welding condition instruction device constructed and arranged to determine a welding condition including a mechanical impedance objective value and a pressing force objective value for each welding point based on information about said each welding point and to issue the determined welding condition as an instruction;a pressing axis control device constructed and arranged to control said pressing axis based on the instruction issued from said welding condition instruction; anda mechanical impedance calculation device constructed and arranged to optimize said mechanical impedance objective value and said pressing force objective value sent from said welding condition instruction device based on measured positional values and measured pressing force values of said pressing axis driven by said pressing axis control device and to feed back the optimized impedance value and the optimized pressing force value to said welding condition instruction device.