Method and apparatus for treating wrapping material for cigarettes or the like

摘要

A running web of wrapping material which is about to be converted into adhesive-coated uniting bands for joining plain cigarettes with filter plugs in filter tipping machines is transported through the passage of a housing wherein the web travels through a series of spark gaps between pairs of spaced-apart electrodes. The sparks which are caused to jump across the gaps perforate the web with attendant development of ozone and particles of dust. The passage of the housing forms part of an endless path for the circulation of Argon which reduces the rate of development of ozone, which is cooled to cool the electrodes, and which is caused to pass through a filter serving to intercept the particles of dust which are removed from the spark gaps. The making of holes in a noble-gas atmosphere prolongs the useful life of the electrodes.