WO2000060961A1

WO2000060961A1 - Comb or multiple comb filter inserted in the cigarette or applicable to devices for smoke or to sources of polluting flows

Info

Publication number: WO2000060961A1
Application number: PCT/IT2000/000144
Authority: WO
Inventors: Romano Murri
Original assignee: Romano Murri
Priority date: 1999-04-14
Filing date: 2000-04-13
Publication date: 2000-10-19
Also published as: ITRM990227A1; AU4312800A

Abstract

Filter device suited to any type of filtering. It consists of a solid element inserted in a conduit through which the flow to be filtered passes; the filter section includes one or more 'comb' elements arranged in such a way that the flow passes by them, together with elements designed to convey the flow.

Description

COMB OR MULTIPLE COMB FILTER INSERTED IN THE CIGARETTE OR APPLICABLE TO DEVICES FOR SMOKE OR TO SOURCES OF POLLUTING FLOWS

DESCRIPTION

This invention, illustrated here with a descriptive and not a limiting coverage of its functioning and potentials for application and manufacturing, consists of a filtering device which has been particularly designed for application inside cigarettes or other devices designed for the smoking of tobacco or similar substances. The possibility of manufacturing very small filters at a low industrial cost makes the production of disposable filters highly attractive for the filtering of tobacco smoke, while recalling the possible use of these filters in a wide variety of fields such as in gaseous fluids and liquids with relatively small filters and structures designed to filter industrial discharge and other materials. The device basically consists of one or more "comb" elements which can have a wide variety of sizes, materials, orientation and other characteristics, in such a way that the combination of the characteristics has the capacity to trap and retain the elements to be removed from the flow. Taking into account the fact that the flow can be produced by a depression downstream from the filter itself or also by pressure upstream from the device, these comb filter elements should be positioned in such a way that the flow can pass towards the part which is the thickest and nearest to the "ridge" of the comb itself. There may also be a configuration with the teeth being thicker in the part farthest away from the ridge, and this should therefore be mounted in an opposite manner with respect to the aforesaid model.

The shape of the comb teeth, the type of surface, the space between them, the material from which they are manufactured and many other factors can improve and of and optimise their efficiency. Therefore any system including comb elements, whether straight, curved or spiral, equipped with teeth of any shape and thickness, from a hair-like thickness to sections resembling lamellas or parallelepiped shapes of significant size in relation to the filter itself, in which the material and the shape of the combs has different functions, must come under this patent. Given the countless manufacturing options, reference will be made, with a descriptive and not a limiting coverage, of the study made for application inside a cigarette.

In the case of a filter applicable in the factory to a cigarette, a series of solutions have been studied to make the device particularly effective and at the same time a very low cost and simple industrial production also enabling a high manufacturing speed, and production in a single casting process without subsequent assembly procedures and processing. One of the advantages of this system consists in the possibility of making a filter without a "front end" to be respected thus making installation easier, while there is still the possibility of producing a filter with a preset directional flow to optimise the results.

Assuming that the flow is to pass through a cylindrical element, placing in a coaxial position to the cylinder another cylindrical element of lesser diameter and non-permeable, or with another shape having the same function, we can achieve the passage of the fluid into a chamber with a circular crown section or similar, should this be closed on one side between the central element and the external surface, and placing the inlet near this element in the inlet part, and near it in the outlet part but in the opposite position, the smoke or the fluid, in order to reach the outlet, should obviously go through a part of the circular crown, since the flow is caused by a depression downstream from the filter. Therefore, placing the ridge or the thickest part of the combs towards the centre of the conduit and shaping the teeth in such a way as to create increasingly narrow spaces between them towards the ridge, and possibly having teeth which are of considerable length and inclined against the flow, the flow would obviously pass though the narrowest part between the teeth and run along the length of these, rising with respect to the natural descending direction.

The various impurities, in the case of tobacco smoke consisting basically of condensate, due to the size, colloidal features, temperature difference and a series of other considerations, are retained by the comb elements between the teeth and on their surface. On the other hand, in the case of a flow deriving from pressure exercised upstream from the filter, the combs could have the ridge towards the external wall since the impure materials under pressure and at considerable velocity, would also be pushed due to centrifugal force to the longest possible way, encountering there the filtering action of the teeth suitably shaped for this purpose. In order to enhance the centrifugal effect the obstructing element inside al filter could have a spiral shape. It could be desirable to alternate combs placed with the ridge facing towards the central element with others place in the contrary way.

In another of the practically infinite configurations the comb elements could be arranged along the two flat surfaces with respect to the inlet and outlet of the flow so that the upper and lower filters alternate, obliging the flow to rise and fall alternately before reaching the exit. The two systems can also be combined, and the combs, shown clearly in the drawings, can alternate on the central cylindrical element and on the surface of the main one, and so on.

Among the many possible solutions, there could be a configuration of the surface of the teeth designed to create, in the direction of the flow, an increasingly rough surface in the direction of the flow or also a configuration including the insertion of absorbent elements in the zones most affected by the flow. The aforesaid configurations and the ones described in the drawings are presented in a descriptive way regarding the comb elements placed in the flow, and in any case are the essential element of this invention as are the shape, position, number and sequence or the alternating between them, or between these and other elements and any other related characteristics, positions, and structures.

It should be considered that the filter represents a conduit in which there is no attempt to increase or decrease pressure or velocity, since these principles are used in previously known systems and have the drawback of causing a physical change in the flow and therefore a perception of their existence and also the a consumption of more of energy. One of the interesting potential solutions is to produce a the filter with a sequence of elements, which may also be made of paper, placed on top of one another, and where the alternating shape of each element forms of pre-set or random shape as well as alternating the size of the comb elements.

DESCRIPTION OF THE ILLUSTRATIONS

Illustration 1

Fig. 1 shows a the longitudinal section of a filter, illustrating the structure and inclination of the combs P. Fig. 2 shows a view of the whole, with the non-permeable element in the centre obliging the flow to take a path inside the filter in the direction shown with FD; Fig. 3 shows a plan with IN and OUT being the inlet and outlet holes of the filter which is obviously without the coating.

Illustration 2 Fig. 4 shows the view of a filter without the non-permeable element. Since the inlet and outlet conduits are place opposite one another on the two surfaces, they force the smoke to flow through the two combs P Fig. 5 shows a plan of the same, with IN and OUT indicating the inlet and the outlet. Fig. 6, 7, 8 show three pictures of combs with teeth and irregular elements.

Illustration 3 Fig. 9 shows a filter with combs P alternating on horizontal planes, with IN and OUT being the inlet and outlet conduits; Fig. 10 shows the diagram of combs P and the direction of the flow.

Illustration 4

Fig. 11 shows the plan of a filter with alternating combs originating from the central element (P) and from the external surface; these are shown with P2. Fig. 12 shows a section of the same, Fig. 13 a filter designed to flow under pressure with peripheral combs P2 only. Illustration 5

Fig. 14 shows a filter inserted in a cigarette, with T being the tobacco, SD the direction of the smoke, IN and OUT the filter inlet and outlet, and P the combs.

Illustration 6

Fig. 15 shows a view of a filter in which NP is the part not permeable to the flow, IN the inlet zone, OUT the outlet zone; the teeth are have a plate profile, thinner in the flow inlet zone and thicker the outlet zone Fig. 16 shows a similar filter but with alternating teeth with parallel profiles.

Claims

1. Filter consisting of a solid element composed of two sections, one for the flow inlet side and the other for the outlet, and between these the long conduit in which the "comb" elements act as filter elements, being placed along the path of the flow itself.

2. As in point 1 but of cylindrical shape with the comb elements placed in radial fashion, with the origin in the central zone not permeable to the flow.

3. As in point 1 but of cylindrical shape with comb elements placed in radial fashion with the origin in the outer coating of the filter and pointing towards the central zone of this.

4. As in point 1 but with comb elements placed starting both from the internal zone {as in point2) and from the peripheral zone (as in point 3).

5. As in point 1 but with comb elements placed on the filter inlet and/or outlet surfaces.

6. As in points 2, 3, 4 and 5 combined together.

7. As in points 1, 2, 3, 4, 5, but with flow conduit elements without the latter acting as filters.

8. As in points 1, 2, 3, 4, 5, 6, but with flow conduit elements of acting as filters.

9. As in points 1, 2, 3, 4, 5, 6, 7, in combination with other types of filters.

10. As in points 1, 2, 3, 4, 5, 6, 7, 8, being inserted in a cylindrical tubular element.

11. As in points 1, 2, 3, 4, 5, 6, 7, 8, but inserted in a conduit which does not have, or does not only have a cylindrical shape.