| 摘要 |
PURPOSE:To improve the reliability of inspection by setting a leading edge detection value, starting storage by passage of the detected value when a current value rises, closing the storage by the passage thereof when the current value drops and making discrimination by the storage from the opening to the closing. CONSTITUTION:When the rising curve of a curve 30 indicating the current between 1/2 cycle of welding current rises and crosses a detection value line 40, a storage element is started and when the falling curve of the curve 30 crosses the line 40, the signal accepting of the storage element is closed. During this time, whether welding is adequate or inadequate is discriminated in accordance with the signals entered the storage element. More specifically, with a current curve 61, a peak value 60 does not arrive at the line 41 indicating a reference lower limit value, and since signal crossing the reference line 41 does not enter the element, the element generates a signal for inadequateness. With a current curve 81, the signal past the line 41 indicating the reference lower limit value and the line 42 indicating the reference upper limit value enters the element, the element generates the signal for adequateness. |
