BRIEF DESCRIPTION OF THE DRAWINGS
Novel features and advantages of the present invention in addition to those mentioned above will be readily apparent to persons of ordinary skill in the art from a reading of the following detailed description in conjunction with the accompanying drawings wherein similar reference characters refer to similar parts and in which:
FIG. 1 is a cross sectional view in elevation of a multi component cigarette filter assembly in accordance with the present invention, and diagrammatically illustrating a heating device for activating the energy activated adhesive only applied between the solid plugs and interior surface portions of the filter tube;
FIG. 2 is a cross sectional view in elevation of a hollow filter tube with a solid plug centrally located within the tube and bands of energy activated adhesive inside the tube at locations where other solid plugs are ultimately positioned;
FIG. 3 is a sectional view in elevation similar to FIG. 2, but illustrating the adhesive at each solid plug location as a single band of adhesive;
FIG. 4 is a cross-sectional view in elevation similar to FIG. 2, but only having adhesive at the outer ends of the hollow filter tube;
FIG. 5 is a cross sectional view in elevation similar to FIG. 3, but only having adhesive at the outer ends of the hollow filter tube;
FIG. 6 is a front elevational view of a solid plug with bands of adhesive on the outer surface thereof; and
FIG. 7 is a front elevational view of a solid plug with a single band of energy activated adhesive on the exterior thereof.
DETAILED DESCRIPTION OF THE INVENTION
Referring in more particularity to the drawings, FIG. 1 illustrates a multi component cigarette filter assembly 10 which forms a two-up dual filter. When the assembly 10 is combined with wrapped tobacco rods (not shown), one at each end thereof, two complete cigarettes are ultimately produced when the assembly is cut at its midpoint.
Fundamentally the cigarette filter assembly 10 comprises a paper tube 12 with a solid fiber plug 14 centrally located within the tube. Particulate filter material 16 such as granulated carbon or carbon beads, for example, is located adjacent the centrally located fiber plug 14 at the opposite ends thereof. An inside solid plug 18 is positioned against each deposit of the particulate material to thereby seal the material in place. Another charge of particulate material 20 is deposited against each inside solid plug 18 and such material may be the same or different from the particulate material 16. Ultimately the particulate material 20 is sealed in place within paper tube 12 by end solid plugs 22.
As explained above, the upper half of the paper tube 12 is often filled with particulate material 16, 20 and solid plugs 18, 22, and the tube may then be inverted to fill the opposite end in a similar manner. Each assembly 10 produces an a pair of individual cigarette filters each having an approximate length of 30 mm, but the length can be shorter or longer, if desired.
As explained more fully below, the end plugs 22 are positively secured to the inner surface of the paper tube 12 by energy activated adhesive. Alternatively, both the end plugs 22 and the inside solid plugs 18 may be secured to the paper tube 12 by energy activated adhesive. The adhesive is such that upon activation it melts or otherwise becomes tacky to secure the plugs to the paper tube. Prior to activation the adhesive remains dry and does not interfere with overall production of the filter assembly 10. Heat 24 may be applied thereafter to melt the adhesive and secure the plugs to the interior surface of the paper tube 12 where the plugs are located.
In FIG. 2 several bands of energy activated adhesive 26 are applied to the interior surface 28 of paper tube 12 at those predetermined locations where the solid plugs 18 and 22 are ultimately positioned. After the cigarette filter assembly is completed energy such as heat 24 is applied to the bands 26 of the adhesive to thereby melt the adhesive and secure the plugs 18, 22 to the interior surface 28 of the paper tube 12. It is important that the adhesive is only applied to those locations inside the paper tube where the plugs will ultimately be positioned. No adhesive is located in the cavities between the plugs where the particulate material 16, 20 is ultimately deposited.
FIG. 3 is similar to FIG. 2, but the adhesive is applied as a single band 30 rather than the multiple bands 26. Otherwise the assembly 10 is the same.
FIGS. 4 and 5 illustrate modified embodiments of the present invention where the energy activated adhesive is only applied on the interior surface 28 of the paper tube 12 where the end plugs 22 are ultimately positioned. The interior solid plugs 18 are held in position by frictional engagement with the paper tube 12 as well as by the deposits of particulate material 16, 20 at opposite ends of the plugs 18. FIG. 4 illustrates the energy activated adhesive applied as multiple bands 26 while FIG. 5 illustrates a single band 30 of adhesive. Otherwise the paper tubes are the same.
FIGS. 6 and 7 illustrate other modifications of the present invention where the adhesive is applied to the exterior of one or both solid plugs 18, 22 rather than the adhesive being pre-applied to the interior of the paper tube. In FIG. 6 the solid end plug 22 includes several bands 26 of energy activated adhesive on the exterior surface of the plug while in FIG. 7 a single band 30 is applied. Both solid plugs 18 and 22 may include adhesive on the exterior thereof in the form of multiple bands or a single band. Alternatively, the adhesive may simply by applied to the exterior of the end plugs 22.
The plugs 14, 18 and 22 are preferable made from cellulose acetate fibers. However, other plug configurations may also be used such as solid plugs with one or more passageways therethrough that allow smoke flow through the plugs of the filter.
Patent Application
20080078416
