Method and apparatus for forming an air dilution filter
US4369796A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 14, 1980 |
| Grant date | Jan 25, 1983 |
| Priority date | — |
| Expiry date | Mar 14, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T82/16983
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
The air dilution filter of the cigarette is provided with an annular zone in the plug wrap paper which enables air to pass directly into the fibrous body of the filter material after passing through apertures in the tipping paper. The annular zone can be comprised of a groove which is fabricated by a pair of rotating knives and a rotatable spacer with radial cutting edges which rout out material from each filter plug during conveyance of the plug on an alignment drum of a cigarette making machine. Alternatively, a plurality of closely spaced rotating knives which cut through the plug wrap paper only may be used to form a series of closely spaced annular grooves or slits in the filter periphery.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.