| 摘要 |
PURPOSE:To reduce the dispersion of a resonance frequency and to execute the improvement of production yield and the stabilization of quality by monitoring the melting diameter of the welding zone of a spring material and controlling a welding power in order to make the melting diameter constant if the melting diameter exceeds a specified value. CONSTITUTION:By monitoring the melting diameter D of the welding zone of a welded load arm 1 by a TV monitor 5, a welding power controller 7 executes the control of a power unit 8 so as to control the welding power which is an output from an oscillator 6 when the melting diameter D is out of the specified value. Thus, the melting diameter D becomes constant. When the welding power during the execution of a vacant hitting is monitored with laser light quantity from a dichroic mirror 10 by a power monitor 9 and the value is out of the specified value, the welding power controller 7 executes the control of the power unit 8 so as to control the welding power which is the output from the oscillator 6, so that the melting diameter D becomes constant. Thus, the dispersion of the resonance frequency of a head spring part can be reduced. |
