| 摘要 |
PURPOSE: A method and an apparatus for manufacturing a spark plug are provided to determine an accurate gap regardless of inclination of a workpiece with respect to the measuring unit, while achieving improved accuracy of manufacture. CONSTITUTION: A spark plug comprises a center electrode(W1) disposed within an insulator, a metallic shell(W3) disposed outside the insulator, and a ground electrode(W2) having an end joined to an end face of the metallic shell, an opposite end portion bent such that a side surface of the opposite end portion faces an end face of the center electrode so as to form a spark gap(G) between the side surface and the end face. A method for manufacturing a spark plug comprises a photographing step for photographing the spark gap by use of a photographing unit, a gap calculation step for determining a gap which includes defining a reference point on the basis of image information obtained from the photographing step, defining a plurality of measurement lines passing through the reference point, measuring along each of the measurement lines a distance between a ground electrode spark gap definition portion of the ground electrode facing the spark gap and a center electrode spark gap definition portion of the center electrode facing the spark gap, and determining a gap on the basis of the measured distance, and an after-treatment step for performing a predetermined after-treatment on the basis of the calculated gap.
|
