Tobacco filter and method of removing impurities from tobacco smoke
US4253476A · kind A · utility
Inventor
Key dates
| Filing date | Jul 31, 1978 |
| Grant date | Mar 3, 1981 |
| Priority date | — |
| Expiry date | Jul 31, 1998 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA24F7/04
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A tobacco filter having a hollow cylindrical body which is preferably transparent, is provided with a plurality of small holes in its outer wall, and with a solid impermeable hit-stick coaxially positioned within the hollow body. A porous annular-shaped filter element surrounds the axial mid-part of the hit-stick. Impurities in tobacco smoke are removed by a process of hit-sticking extraction in the form of numerous black dots on the surface of the hit-stick as well as the result of automatic, rapid self-liquefication of the filter element. At one end of the hollow cylindrical body a filter tip is positioned to be held in the mouth of the smoker, and at the other end is a cigarette holding part for receiving and holding a conventional cigarette. The hit-sticking extraction results from air jets being drawn into an annularly shaped passageway located between the outer surface of the hit-stick and the inside surface of the hollow cylindrical body and through which smoke flows axially as the smoker draws on the filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.