Spark perforation of web material
US4635653A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 19, 1983 |
| Grant date | Jan 13, 1987 |
| Priority date | — |
| Expiry date | May 19, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N15/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Filter cigarettes with a predetermined dilution factor are produced by perforating a filter attachment web by means of an adjustable perforating device prior to using portions of the web to join filters to cigarettes; measuring the porosity of the perforated web; measuring the dilution of cigarettes assembled with portions of the web; and controlling the perforating device by immediate response to the measured porosity and by progressive response to the dilution of the assembled cigarettes. The perforating device may comprise spark perforating electrodes, the web being possibly passed twice between the electrodes. In particular, the perforating device includes a number of pairs of electrodes defining spark gaps therebetween and lying along a line inclined to the direction of movement of the web. Individual rod electrodes are located between and spaced from opposed metal plates connected to a power supply to form capacitances in series with the spark gaps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.