CPC Subgroup
H01T 21/04 Cleaning (means for self-cleaning H01T13/14; abrasive blasting devices for cleaning sparking-plugs B24C3/34)
Full Title
Apparatus or processes specially adapted for the manufacture or maintenance of spark gaps or sparking plugs > of sparking plugs > Cleaning (means for self-cleaning H01T13/14; abrasive blasting devices for cleaning sparking-plugs B24C3/34)