| 摘要 |
PROBLEM TO BE SOLVED: To judge quality in real time and also judge good/bad conditions without a breakage test by providing a step for detecting a variable pressurizing force and a step for judging good/bad conditions of welding by means of a computer from variation of the detected pressutizing force. SOLUTION: One pair of electrodes 5, 6 nipping a projection 1 of first and second members 3, 4 are pressurized by pressurizing devices 9, 10. A switch/ control mechanism 13 is connected to the pressurizing device 9, and passages of an operational fluid source 11 and a drain 12 are switched so as to control the pressurizing force of the electrode 5. Pressurizing force detection sensors 17, 18 are installed to pressurizing rods of the pressurizing devices 9, 10, and an electric output is inputted into a computer 21 so as to judge good/bad conditions of welding. It is preferable that good/bad conditions of projection welding are judged based on whether or not a projection crashing time Tt from starting deterioration of the pressurizing force from a target pressurizing force till the force becomes the target pressurizing force again is in a given time range, or whether or not a pressurization time Tm from the start of pressurization till the start of crashing the protrusion is in within a given time range.
|
