| 摘要 |
A method of producing a rotationally orientated thread starting at a desired angular position and suitable for mass production is provided. The method is particularly suitable for improving the angular positioning of spark plugs in car engines. The method involves measuring precisely the length (L) of the tool (13) and the distance, at a particular angular position, of a full thread form (14) of the thread to the tip, so that its start position at the tip can be calculated. Using that distance as an offset of the length of the tool reported to the CNC machine, and starting from its reference position, it commences producing the thread (12) in the bore (11) at the desired angular position of the bore (11). |
