Smoking device

A smoking device having a cylindrical fuel rod circumscribed by an air impermeable wrapper. The fuel rod consists of a homogeneous mixture of a non-tobacco fuel, a non-combustible tobacco, an aerosol generating material and a heat sink material.

BACKGROUND OF THE INVENTION 
The present invention relates to smoking devices, and more particularly, to 
a smoking device which includes a fuel rod consisting of a non-combustible 
tobacco, a non-tobacco fuel, an aerosol generating material and flavor 
generating material. 
A smoking article including a tobacco and a non-tobacco fuel are, per se, 
known. For example, U.S. Pat. No. 2,907,686 teaches a substitute for 
tobacco which is an activated or non-activated carbon impregnated with a 
flavoring oil such as vanilla; U.S. Pat. No. 2,976,190 teaches a cigarette 
having a tobacco column wrapped by conventional cigarette paper wherein 
the interior surface of the paper wrapper, that is the surface in contact 
with the tobacco column, is coated with metal particles and the metal 
particles absorb heat to reduce the temperature of the burning cigarette; 
U.S. Pat. No. 3,258,015 teaches a smoking device having a cylindrical 
tobacco rod which can have mixed therein a smoldering enhancing compound 
such as sodium chlorate, potassium chlorate, sodium nitrate or potassium 
nitrate and includes a metal tube extending coaxially through the tobacco 
rod filled with tobacco or a tobacco extract and an aerosol forming 
material; U.S. Pat. No. 3,674,036 teaches a cigarette having a tobacco rod 
in axial alignment with a filter rod with a porous partition being located 
at the interface of the tobacco rod and filter, the tobacco rod being 
provided with a thin walled, tubular perforated core coaxially embedded in 
the tobacco rod wherein the core is fabricated of a thin combustible paper 
and the filter rod is provided with a recess to catch liquid concentrate 
and impurities of combustion; U.S. Pat. No. 4,340,072 teaches a smoking 
device having a cylindrical air impervious fuel rod with a central passage 
therethrough and a chamber located at one end of the fuel rod with a 
filter located at the end of the chamber wherein the chamber is formed of 
an air impermeable material containing an aerosol precursor of a volatile 
flavor solution and the fuel rod is formed of a tobacco substitute and 
carbon; U.S. Pat. No. 4,510,950 teaches a cigarette having a combustible 
fuel rod fabricated of a mixture of tobacco particles and a filler of 
calcium carbonate, magnesium carbonate, calcium oxide, magnesium oxide, 
calcium hydroxide, magnesium hydroxide, alumna, hydrated alumna, clay or 
silica and the fuel rod has a density within the range of from 0.05 to 
about 1.5 gcc; and, European Patent Application No. 0245732 teaches a 
smoking article having a cylindrical fuel element fabricated of a 
pyrolyzed non-tobacco fibrous material with a stainless steel tube 
centrally located with the fuel element filled with a substrate material 
bearing aerosol forming substances wherein the substrate can be carbon, 
ceramics, or metal and the aerosol forming substances can be polyhydric 
alcohols. 
SUMMARY OF THE INVENTION 
The present invention provides a smoking article comprising a fuel rod 
comprising a homogeneous mixture of a non-combustible tobacco; a 
non-tobacco fuel; an aerosol generating material which aerosolizes at a 
temperature below the burning temperature of the non-tobacco fuel; an air 
impermeable paper wrapper circumscribing the fuel rod; and, a coaxially 
extending filter rod at one end of the fuel rod.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
With reference to FIG. 1, there is shown a smoking device, generally 
denoted as the numeral 10, of the present invention which includes a 
cylindrical fuel rod 12, an air impermeable paper wrapper 14 
circumscribing the fuel rod 12, and a filter 16 coaxially located at one 
end of the fuel rod 12 and attached to the fuel rod 12 by a tipping 
material 18 circumscribing the filter 16 and overlapping the end of the 
fuel rod 12 adjacent the filter 16. 
The fuel rod 12 is a homogeneous mixture comprising a non-combustible 
tobacco, a non-tobacco fuel, an aerosol generating material, a flavor 
generating material, and a heat absorbent material. An appropriate binder 
can also be included in the mixture as a cohesive to hold the other 
components together. 
The non-tobacco fuel is preferably selected from a group of materials such 
as, for example, charcoal, aluminum, or magnesium. The non-tobacco fuel is 
in the form of small particulate or powder to provide increased surface 
area. 
The non-combustible tobacco can be, for example, reconstituted tobacco 
treated with a burn retardant material, such as diammonium phosphate, mono 
ammonium phosphate and ammonium polyphosphate to raise the combustion 
temperature of the tobacco to above the combustion temperature of the 
non-tobacco fuel. Preferably, the non-combustible tobacco comprises no 
more than 20 g by weight of the fuel rod. 
The aerosol generating material forms an aerosol or aerosolizes below the 
combustion temperature of the non-tobacco fuel. The aerosol generating 
material can be, for example, glycerine or propylene glycol. 
The flavor generating material is preferably a material which will release 
flavors by diffusion into the aerosol at a temperature below the 
combustion temperature of the non-tobacco fuel. Tobacco extracts and 
menthol are examples of such flavors. 
The heat absorbent material is included in the fuel rod as a heat sink for 
the absorption of heat and to control the temperature of the mixture. The 
heat absorbent material can be an inert metal oxide, such as alumna or 
magnesium oxide. 
The binder material can be of the type typically used in conventional 
cigarettes, for example, sodium carboxymethylcellulose, pectin, and 
hydroxypropylcellulose. 
The smoking device 10 of FIG. 1 can be made by conventional cigarette 
making processes. In such known process the components of the fuel rod are 
mixed together and formed into a sheet and can be cut and formed into a 
rod like tobacco in a conventional cigarette. The sheet can also be 
attenuated and rolled into cylindrical form wrapped in the paper wrapper 
14, and cut to a preselected length. 
Now with reference to FIGS. 2 and 3, there is shown another embodiment of a 
smoking device, generally denoted as the numeral 110, of the present 
invention which includes a cylindrical fuel rod 112, an air impermeable 
paper wrapper 114 circumscribing the fuel rod 112, and a filter 116 
coaxially located at one end of the fuel rod 112 and attached to the fuel 
rod 112 by a tipping material 118 circumscribing the filter 116 and 
overlapping the end of the fuel rod 112 adjacent the filter 116. The fuel 
rod 112 is formed with a plurality of channels 120 extending 
longitudinally through the fuel rod from one end to the other end of the 
fuel rod 112. As shown, there are five channels 120 oriented such that one 
channel 120 extends concentrically through the fuel rod, and the other 
four channels are in a circumferentially spaced array around the 
concentrically disposed channel. Preferably, the distance between the 
concentrically disposed channel and each one of the other channels 
measured radially of the fuel rod 112 is equal to the distance separating 
adjacent ones of the other channels 120. 
As with the fuel rod 12, the fuel rod 112 is a homogeneous mixture 
comprising a non-combustible tobacco, a non-tobacco fuel, an aerosol 
generating material, and a heat absorbent material. 
The fuel rod 112 is a homogeneous mixture comprising a non-combustible 
tobacco, a non-tobacco fuel, an aerosol generating material and a heat 
absorbent material all of the type discussed above in regard to the 
smoking device 10 of FIG. 1. 
The fuel rod 112 is compressed to a higher density than that of the tobacco 
rod of a conventional cigarette or that of the fuel rod 12. The density of 
the fuel rod 112 is in the range of 0.4 gm/cc to 1.5 gm/cc. Due to the 
higher density, the combustion temperature of the tobacco component is 
increased to the extent that the amount of burn retardant material can be 
reduced from that used in the fuel rod 12, and possibly even be eliminated 
from the fuel rod 112. The channels 120 are used to supply combustion 
supporting air to the interior of the fuel rod 112 as a smoker draws the 
filter 116. 
In addition, if need be, an oxidizer material can be mixed with the other 
components of the fuel rod 112 to supply further combustion supporting 
oxygen. One suitable oxidizer material is potassium nitrate. 
The fuel rod 112 can he made by forming a suitable slurry of the fuel rod 
components and extruding the slurry to form the higher density fuel rod 
112. The channels 120 can be formed during the extrusion of the fuel rod. 
In both of the embodiments described above, the heat generated by the 
burning non-tobacco fuel component will vaporize the volatiles in the 
tobacco. The aerosol generated by the aerosol generating material will 
pick up or entrain these released volatiles and carry them to the mouth of 
the smoker. 
The foregoing detailed description is given primarily for clearness of 
understanding and no unnecessary limitations are to be understood 
therefrom for modifications will become obvious to those skilled in the 
art upon reading this disclosure and may be made without departing from 
the spirit of the invention and scope of the appended claims.