I 111111111111111111111111111111111111 IIIII IIIII IIIII IIIII 111111111111111111
`US005353813A
`5,353,813
`[11] Patent Number:
`[45] Date of Patent: Oct. 11, 1994
`
`4,966,171 10/1990 Serrano et al ....................... 131/194
`4,970,189 11/1990 Tachibana ........................... 502/183
`4,981,522 1/1991 Nichols et al ....................... 131/274
`4,991,606 2/1991 Serrano et al ....................... 131/359
`5,040,552 8/1991 Schleich et al ..................... 131/359
`5,060,671 10/1991 Counts et al ........................ 131/359
`5,076,296 12/1991 Nystrom et al ..................... 131/359
`5,093,894 3/1992 Deevi et al. ......................... 392/390
`5,095,921 3/1992 Losee et al .......................... 131/194
`5,157,242 10/1992 Hetherington et al. .
`5,159,940 11/1992 Hayward et al .................... 131/194
`5,224,498 7 /1993 Deevi et al .......................... 131/194
`5,228,460 7/1993 Sprinkel et al ............. 128/203.27 X
`FOREIGN PA TENT DOCUMENTS
`0295122 12/1988 European Pat. Off ..
`60-44963 3/1985 Japan .
`61-12918 1/1986 Japan .
`61-32958 2/1986 Japan .
`61-86411 5/1986 Japan .
`OTHER PUBLICATIONS
`Kinoshita, K., "Manufacture of Carbons for Electro(cid:173)
`chemical applications," Carbon: Electrochemical and
`Physicochemical Properties, pp. 10-14.
`Dummer, G. W. A., Materials for Conductive and Re(cid:173)
`sistive Functions (Hayden Book Company, Inc., New
`York 1970), chapter 12.
`
`Primary Examiner-Jennifer Bahr
`Attorney, Agent, or Firm-Charles E. B. Glenn; James E.
`Schardt; Kevin B. Osborne
`ABSTRACT
`[57]
`A bladed tubular array for use as a heating element in an
`electrical smoking article, and a tobacco flavor element
`for such an article based thereon, are provided. The
`integral carbon heater preferably provides eight ther(cid:173)
`mally and electrically discrete heating zones to provide
`an optimized heating zone when each blade is individu(cid:173)
`ally powered. Each blade has a desired resistance, to
`provide temperature preferably in the range of from
`about 300° C. to about 900° C., or higher. The relatively
`brittle carbon composite conductive blades are sup(cid:173)
`ported by a reinforcing tube of spiral-wound• paper(cid:173)
`board. A common ring of the same conductive material
`serves as a common electrical terminal for the blades,
`while the free end of each blade serves as the other
`electrical terminal of that blade.
`62 Claims, 6 Drawing Sheets
`s-1
`
`66
`
`15
`
`United States Patent [191
`Deevi et al.
`
`[75]
`
`[54] REINFORCED CARBON HEATER WITH
`DISCRETE HEATING ZONES
`Inventors: Seetbarama C. Deen; Grier S.
`Fleiscbbauer, both of Midlothian;
`Billy J. Keen, Jr., Chesterfield, all of
`Va.
`
`[73] Assignee: Philip Morris Incorporated, New
`York, N.Y.
`[21] Appl. No.: 931,997
`[22] Filed:
`Aug. 19, 1992
`Int. Cl.0 .............................................. A24F 47/00
`[51]
`[52) U.S. CI. .................................... 131/194; 131/329;
`131/273
`[58] Field of Search ............... 131/194, 195, 270, 271,
`131/273,329;219/240, 543,254;392/386,403,
`404; 128/203.17, 203.27; 338/306-310, 225,
`226, 332, 294
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`1,771,366 7/1930 Wyss et al ..
`2,971,039 2/1961 Westeren .
`2,997,451 8/1961 Miller .
`3,057,936 10/1962 Hill .
`3,178,665 4/1965 Matheson et al ..
`3,200,819 8/1965 Gilbert ................................ 128/200
`3,420,985 1/1969 Anderson et al ..
`3,444,183 5/1969 Hubbuch ............................ 260/32.6
`3,521,643 2/1968 Toth .................................... 128/261
`3,563,916 2/1971 Takashina et al ................... 252/511
`3,587,573 6/1971 Flack ................................... 128/201
`3,726,984 4/1973 Anthony et al ..
`4,215,708 8/1980 Bron ................................ 131/262 B
`4,503,319 3/1985 Moritoki et al ..
`4,609,972 9/1986 Edeling et al ....................... 361/433
`4,686,353 8/1987 Spector .
`4,775,655 10/1988 Edwards et al ..................... 502/416
`4,799,957 1/1989 Vogel .................................... 75/243
`4,822,538 4/1989 Yoshida et al ..................... 264/29.4
`4,847,021 7/1989 Montgomery et al ............. 264/29.3
`4,849,251 7/1989 Tanaka ................................ 427/101
`4,877,554 10/1989 Honma et al ....................... 252/511
`4,883,617 11/1989 Benn et al ...................... ~ ... 264/29.7
`4,902,562 2/1990 Bahia ................................... 428/283
`4,916,292 4/1990 Kawakubo et al ................. 219/553
`4,917,923 4/1990 Yoshida et al ..................... 428/34.1
`4,919,779 4/1990 Mizoguchi et al ............... 204/192.3
`4,921,559 5/1990 Odajima .............................. 156/242
`4,950,443 8/1990 Kawakubo et al ...•........•... 264/29.5
`
`14 11
`
`Ex. 2038-0001
`
`

`

`U.S. Patent
`
`Oct. 11, 1994
`
`Sheet 1 of 6
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`5,353,813
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`66
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`15
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`11 v2
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`FIG.1
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`15
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`1
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`15
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`1
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`FIG. 2
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`Ex. 2038-0002
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`

`U.S. Patent
`
`Oct. 11, 1994
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`Sheet 2 of 6
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`5,353,813
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`42
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`FIG. 4
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`52
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`15
`
`FIG. 5
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`Ex. 2038-0003
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`

`

`U.S. Patent
`US. Patent
`
`Oct. 11, 1994
`Oct. 11, 1994
`
`Sheet 3 of 6
`Sheet 3 of 6
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`5,353,813
`5,353,813
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`
`
`Ex. 2038-0004
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`Ex. 2038-0004
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`

`

`U.S. Patent
`US. Patent
`
`Oct. 11, 1994
`Oct. 11, 1994
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`Sheet 4 of 6
`Sheet 4 of 6
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`5,353,813
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`U.S. Patent
`U.S Ptnt
`
`Oct. 11, 1994
`
`Sheet 5 of 6
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`5,353,813
`5,353,813
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`

`

`U.S. Patent
`US. Patent
`
`Oct. 11, 1994
`Oct. 11, 1994
`
`Sheet 6 of 6
`Sheet 6 of 6
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`5,353,813
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`

`

`1
`
`5,353,813
`
`REINFORCED CARBON HEATER WITH
`DISCRETE HEATING ZONES
`
`2
`Therefore, in accordance with the present invention
`there is provided a heating element for an an electrical
`smoking article. The heating element has a mouth end
`and a rod end and includes a ring or hub having a cen-
`BACKGROUND OF THE INVENTION
`5 tral axis, and a plurality of electrically conductive
`blades attached to the ring and extending in one direc(cid:173)
`This invention relates to electric heating elements
`tion parallel to the central axis. Each of the blades has a
`used to heat a tobacco flavor generating medium in an
`free end remote from the ring. The heating element has
`electrical smoking article. In particular, this invention
`a hollow central core circumscribed by the ring and the
`relates to such a heating element arranged in a tubular
`blades. Finally, the heating element has support means
`array.
`disposed within the hollow central core for supporting
`One type of electrical smoking article is disclosed in
`the blades.
`commonly-assigned U.S. Patent No. 5,060,671 which is
`hereby incorporated by reference in its entirety. In such
`A tobacco flavor element for such an electrical smok(cid:173)
`an electrical smoking article, a flavor bed of a tobacco 15
`ing article is also provided, incorporating the heating
`flavor medium, such as tobacco or tobacco-derived
`element and a mouthpiece tube disposed about the heat(cid:173)
`substances, is heated electrically to release a tobacco
`ing element, thereby forming a fluid flow passage be(cid:173)
`flavor substance without burning. As the tobacco flavor
`tween the inner wall and the blade portion circumfer(cid:173)
`medium is heated, a smoker at the mouth or down(cid:173)
`ence. The mouthpiece tube has inner and outer walls
`stream end of the device draws air in and around the 20
`and contact means on the inner wall for electrically
`heating element by inhaling, and thereby receives the
`contacting the ring. The tobacco flavor element also
`tobacco flavor substance.
`includes socket means having first electrical connector
`The above-identified application discloses a number
`means for electrically contacting the contact means on
`of possible heater configurations, many of which are
`the inner wall of the mouthpiece tube, and a plurality of
`made from a carbon composite material formed into a 25
`second electrical connector means, corresponding to
`desired shape. For example, one configuration involved
`the plurality of blades, for electrically contacting each
`a radial array of blades connected in common at the
`of the free ends of the blades. The socket also has main
`center and separately connectable at their outer edges
`connector means for connecting to a power and control
`to a source of electrical power. By depositing tobacco
`module of an electrical smoking article, as well as means
`flavor medium on each blade and heating the blades 30
`for providing fluid communication between external
`individually, one could provide a predetermined num(cid:173)
`atmosphere and the fluid flow passage adjacent the rod
`ber of discrete puffs to the smoker. Other configurations
`end. A tobacco flavor medium is disposed on the blades.
`included various linear and tubular shapes, subdivided
`BRIEF DESCRIPTION OF THE DRAWINGS
`to provide a number of discrete heating areas.
`Other configurations have been proposed. For exam- 35
`The above and other objects and advantages of the
`pie, various arrays of discrete fingers or blades of heater
`invention will be apparent upon consideration of the
`material can be provided, each blade providing one
`following detailed description, taken in conjunction
`puff. However, suitable heater materials, such as those
`with the accompanying drawings, in which like refer-
`described in said above-incorporated U.S. Pat. No.
`ence characters refer to like parts throughout, and in
`5,060,671 are generally not strong enough to be ar- 40 which:
`ranged in such a blade configuration without threat of
`FIG. 1 is a rod end perspective view of a preferred
`blade breakage. This is particularly true of a preferred
`embodiment of a heating element in accordance with
`material made by mixing carbon, fillers and binders and
`the present invention;
`curing and heating the mixture until the desired resistiv-
`FIG. 2 is rod end elevational view of the heating
`ity is achieved. This material has been found to have the 45 element of FIG. 1 taken from line 2-2 of FIG. 1;
`proper electrical resistivity characteristics and evolves
`FIG. 3 is a mouth end elevational view of the heating
`no undesirable constituents when heated to operating
`element of FIGS. 1 and 2 taken from line 3-3 of FIG.
`temperature.
`1;
`Further, as disclosed in said above-incorporated U.S.
`FIG. 4 is longitudinal cross-sectional view of the
`Pat. No. 5,060,671, such heating elements are preferably so heating element of FIGS. 1-3, taken from line 4-4 of
`disposable and replaceable. Therefore, they must be
`FIG. 3;
`relatively inexpensive to produce.
`FIG. 5 is a perspective view of a precursor of the
`It would be desirable to be able to provide an array of
`heating element of FIGS. 1-4;
`heater blades or fingers that is sufficiently strong for use
`FIG. 6 is a fragmentary perspective view taken from
`in an electrical smoking article without danger of break- 55 the rod end of a first preferred embodiment of a flavor
`age.
`generating element according to the present invention,
`It is also desirable to be able to provide such an array
`incorporating the heating element of FIGS. 1-5;
`of heater blades that is sufficiently inexpensive to manu-
`FIG. 7 is a longitudinal cross-sectional view of the
`facture that it can be disposable.
`tobacco flavor element of FIG. 6, taken from line 7-7 of
`60 FIG. 6;
`SUMMARY OF THE INVENTION
`FIG. 8 is a longitudinal cross-sectional view of a
`It is an object of this invention to provide an array of
`second preferred embodiment of a tobacco flavor ele(cid:173)
`heater blades or fingers that is sufficiently strong for use
`ment according to the present invention, incorporating
`in an electrical smoking article without danger of break-
`the heating element of FIGS. 1-5;
`age.
`FIG. 9 is a longitudinal cross-sectional view of a third
`It is also an object of this invention to provide such an
`preferred embodiment of a tobacco flavor element ac(cid:173)
`array of heater blades that is sufficiently inexpensive to
`cording to the present invention, incorporating the
`manufacture that it can be disposable.
`heating element of FIGS. 1-5; and
`
`10
`
`65
`
`Ex. 2038-0008
`
`

`

`5,353,813
`
`5
`
`3
`4
`FIG. 10 is a mouth end elevational view of the to(cid:173)
`the rod end of the void to the outside air. The above(cid:173)
`bacco flavor element of FIG. 9, taken from line 10-10
`mentioned extensions through the ring of the spaces
`of FIG. 9.
`between the blades connect the mouth end of the void
`to the outside air.
`DETAILED DESCRIPTION OF THE
`The invention will now be more particularly de(cid:173)
`INVENTION
`scribed in connection with its preferred embodiments,
`The heating element of the present invention is a
`with reference to the FIGURES. A preferred embodi-
`tubularly-arranged array of finger-like heater blades
`ment of the heating element 10 of the invention is shown
`connected to a common ring that serves as a common
`in FIGS.1-4. As shown, heating element 10 is generally
`electrical terminal. The heating element is unitarily 10 cylindrical, with cylindrically-arranged carbon com-
`formed from an electrically conductive composition
`posite blades 11 unitarily formed with carbon composite
`such as, preferably, the carbon composite material re-
`ring or collar 12 and rearward tubular carbon compos-
`ferred to above, with a reinforcing inner tube of paper-
`ite extension 13. Spaces 14 between blades 11 extend
`board or similar material. The blades all extend in one
`through ring 12 as passages 15.
`direction from the ring, parallel to the central axis of the 15 Reinforcing tube 40 is disposed in the hollow center
`ring, so that the overall appearance of the heating ele-
`of heating element 10 and has an outer diameter substan-
`m~nt is of a cylindrical element h~ving a ring at one end
`tially the same as the inner diameter of the carbon com-
`with a number of blades extendmg ~oward the ot~er
`posite portion of heating element 10, so that reinforcing
`end, _where each blade end serves as its own electncal
`tube 40 supports blades 11 against breakage. Reinforc-
`termmal. The number of blades corresponds to_ the n?JJ:?- 20 ing tube 40 may have optional depressions 42 adjacent
`ber of puffs (preferably, e.g., at least about eight) 1t 1s
`blades 11 for
`O 8 to b d"
`db 1 R · fi
`·
`desired to provide in an electrical smoking article into
`t b
`ta
`re;s n t
`e i~cuss
`
`ti°w. ehm ordcifing
`40
`which the heating element is to be incorporated, and the
`alperds. own d0b0 P
`a I s mout en or
`u e
`enmg
`.
`.
`.
`reasons so 1scusse
`e ow.
`1
`portion of the crrcumference occupied by the blades
`H f
`t 10
`b
`d f
`•
`I
`exceeds the portion of the circumference occupied by 25
`ea mg e eJJ:?en
`may e ma e rom an ~ntegral
`the spaces between the blades. The ring has a greater
`carbo~ c~mpos1te precursor element 50, shown Ill FIG.
`5, which 18 preferably extruded or molded with central
`diameter than the remainder of the heating element and
`bore 51 and passages 15 already provided. T~e o_uter
`the spaces between the blades extend through the ring,
`for reasons which will become more apparent below.
`surface 52 ofpr~curso_r elemen~ 50 corre~ponds m diam-
`When the heating element of the present invention is 30 eter to that of nn~ 12 m t~e firushed ~eatmg elem~nt 10.
`included in a tobacco flavor element, for subsequent
`Outer s~rface 52 IS machined down m ar:a 43, without
`inclusion in an electrical smoking article, its blades are
`penetratmg_ passag~s 15, to form ext:ns1on 13. Outer
`coated with a tobacco flavor medium such as that dis-
`surface 52 IS machined down further m area 44, pene-
`closed in said above-incorporated U.S. Pat. No.
`trating passages 15 to form spaces 14 and individual
`5,060,671.
`35 bl~des 11. The methods used to form, and to machine or
`The coated heating element is surrounded by a tube.
`gnnd, precursor element SO may be those described in
`The inner surface of the tube sits on the portion of the
`co-pending, commonly assigned U.S. patent application
`heating element which has the greatest diameter, which
`Ser. N~. 07 /932,224, filed concu~e~tly h:rewith and
`is the ring. Thus the inner surface of the tube is the
`here~y mc~rporated by ~eference m its entrrety.
`preferred choice for completing the electrical connec- 40 Remforcrng tube 40 1s preferably made of paper-
`tion to the outer surface of the ring. Appropriate metal-
`board, such as hard-calendared paperboard or card-
`lie or other conductive terminals contact the inner sur-
`board, which is substantially non-combustible at the
`face of the tube, and also mechanically connect the tube
`temperatures at which heating element 10 is expected to
`to the remainder of the tobacco flavor element. Similar
`operate. Tube 40 may be formed by any suitable tube
`terminals contact the respective blade ends.
`45 forming technique, such as conventional spiral-wound
`For this purpose, a conductive metallic layer is
`tube making processes. Tube 40 can be inserted into
`coated or laniinated onto the inner surface of the tube.
`element 50 either before or after grinding of element SO,
`Similarly, a metallic layer is applied to the outer surface
`but is preferably inserted before grinding so that it can
`of the ring to reduce contact resistance between the
`support blades 11 during the grinding operation as well
`outer surface of the ring and the inner surface of the so as afterwards. The tapered portion of tube 40, referred
`tube. Some examples of appropriate techniques for ap-
`to above, assists in insertion of tube 40 into element 50,
`plying the conductive metallic layers are described in
`although it also serves another function as discussed
`G.W.A. Dummer, Materials for Conductive and Resistive
`below. Optionally, tube 40 may be adhered to element
`Functions (Hayden Book Company, Inc., New York
`50 by any suitable adhesive that can withstand the oper-
`1970), which is hereby incorporated by reference in its 55 ating temperatures of heating element 10 without evolv-
`entirety, and particularly in Chapter Twelve thereof.
`ing undesirable compounds that might affect the taste of
`In at least one embodinient the tobacco flavor ele-
`the electrical article.
`ment includes a socket bearing the electrical terminals
`A preferred embodiment of a tobacco flavor element
`and connecting at its remote end to the power and con-
`60 according to the invention is shown in FIGS. 6 and
`trol portion of the electrical smoking article for selec- 60 7. An extension tube 61 fits over extension 13 and is used
`tive energizing of individual blades to generate tobacco
`to mate to heating element 10 a filter 62, which may be
`flavor substance. This socket bears against the ends of made of any suitable filter material, such as cellulose
`the tube and the blades, and, together with the tube, the
`acetate filter material as is commonly used in cigarette
`blades and the ring, defme a void between the blades
`filters. Conventional tipping paper 620 may overlay
`and the inner surface of the tube. It is into this void that 65 filter 62. Tobacco flavor medium 63, such as that dis-
`the tobacco flavor substance is evolved. In order for the
`closed in said above-incorporated U.S. Pat. No.
`smoker to be able to draw on the tobacco flavor sub-
`5,060,671, is deposited on a central portion of each blade
`stance, passages are provided in the socket connecting
`11.
`
`4;
`
`Ex. 2038-0009
`
`

`

`5,353,813
`
`5
`A protective outer tube 64 is disposed around heating
`element 10. The inner surface 65 of tube 64 is coated
`with a conductive material 70, which is in contact with
`the outer surface of ring 12. Conductive material 70
`may be any conductive material that does not evolve 5
`undesirable compounds when heated. Material 70 can
`be in the form of a foil or foil laminate. Preferred mate(cid:173)
`rials are selected from the group consisting of gold,
`aluminum, copper and combinations thereof, and a par(cid:173)
`ticularly preferred material is aluminum, provided as 10
`part of an aluminum foil and paper laminate from which
`tube 64 is spiral-wound. If a metal that oxidizes readily,
`such as aluminum, is used, surface 66 of ring 12 would
`preferably be provided with sharp points (not shown)
`which, during assembly, would break through any 15
`oxide barrier that may have formed an surface 65, to
`insure good electrical contact. In any case, surface 66 is
`itself coated with a conductive material 45, such as
`gold, to decrease contact resistance.
`Connectors 71 on permanent power and control mod- 20
`ule 72 receive tube 64 and hold it mechanically while
`electrically connecting it to module 72. Similar connec(cid:173)
`tors 73, one for each blade 11, mechanically and electri(cid:173)
`cally connect blades 11 to module 72. The ends of
`blades 11 can also be coated with conductive material 25
`45 to decrease contact resistance.
`As disclosed in said above-incorporated U.S. Pat. No.
`5,060,071, module 72 includes a pressure sensitive
`switch (not shown) for sensing when a smoking puffs on
`the electrical smoking article. The interior of reinforc- 30
`ing tube 40, communicating with the smoker's mouth
`through opening 41, serves as the sensing chamber,
`which communicates with the switch through bore 74
`of module 72. The taper of tube 40 at opening 41 serves
`to decrease the likelihood of tobacco flavor substance 35
`entering the sensing chamber and possibly contaminat(cid:173)
`ing the pressure sensitive switch.
`When the smoker puffs on the electrical smoking
`article, causing the heating of tobacco flavor medium 63
`and the resulting production of a tobacco flavor aerosol 40
`in the void or chamber 75 between blades 11 and outer
`tube 64, the smoker must be able to draw that aerosol
`through passages 15. In order for that to occur, air must
`be able to flow into chamber 75 to replace the air drawn
`out. This can be accomplished in the embodiment of 45
`FIGS. 6 and 7 in at least two ways. First, passages 76
`can be provided in module 72 communicating between
`the outside atmosphere and chamber 75. Second, perfo(cid:173)
`rations 77 (additional perforations 77 not shown) can be
`provided in tube 64 and conductive layer 70.
`As discussed above, in order to assure that no unde(cid:173)
`sirable compounds are produced when heating element
`10 is actuated, depressions 42 may be provided in those
`portions of tube 40 underlying areas of blades 11 where
`the most heating will take place (i.e., where tobacco 55
`flavor medium 63 is deposited). This will assure that
`tube 40 will not char and generate off tastes.
`Alternatively, a tobacco flavor material 67 may be
`applied to the outer surface of tube 40, at least in the
`areas underlying blades 11, so that any heating of tube 60
`40 that occurs is used to generate additional tobacco
`flavor aerosol. Such a material may be coated onto the
`surface of tube 40, or may be applied as an outer layer,
`such as a layer 67 of reconstituted tobacco sheet.
`Another preferred embodiment of a tobacco flavor 65
`generating element 80 according to the present inven(cid:173)
`tion is shown in FIG. 8. Tobacco flavor element 80 is
`similar to element 60, except that tube 64, contact layer
`
`SO
`
`6
`70 and connectors or sockets 71 are omitted. Instead
`module 72 has socket extension 81 which is lined with
`contacts 82. A sliding sleeve 83 protects blades 11 and
`tobacco flavor medium 63 of tobacco flavor element 80
`prior to insertion of tobacco flavor element 80 into
`socket 81. Insertion of element 80 into socket 81 causes
`sleeve 83 to be pushed back, allowing contacts 82 to
`contact ring 12. The outer surface of ring 12 in this
`embodiment is machined down a 84 to provide a stop as
`well as a conductive surface which again may be coated
`with conductive layer 70.
`A third preferred embodiment of a tobacco flavor
`element 90 according to the present invention is shown
`in FIGS. 9 and 10. In this embodiment, which is similar
`to embodiments 60 and 80, a socket module 91 is inter(cid:173)
`posed between tobacco flavor element 90 and module
`72. Module 91 has a bore 92 which is the extension of
`bore 74, while leads 93 from connectors 71, 73 terminate
`in plugs 98 that mate with module 72. This embodiment
`also includes an outer protective tube 94 (e.g., of alumi(cid:173)
`num) fixed to socket module 91. This arrangement, as
`illustrated, would block air from entering passages 76.
`For that reason, grooves 95 on the inner surface of tube
`94 overlap passages 76 and allow air to flow out either
`through perforations 96 in the walls of tube 94, or
`though the end wall 97 of tube 94. If the latter option is
`chosen, care must be taken that end 97 is far enough
`from the mouth end that the smoker's lips will not cover
`it. Otherwise, grooves 95 will not serve their purpose of
`allowing outside air into passages 76 when the smoker
`draws on the article at filter 62, because grooves 95 will
`also be in the smoker's mouth.
`Heating element 10 and tobacco flavor element 60,
`80, 90 are relatively inexpensive to produce, being made
`from the carbon composite material and relatively inex(cid:173)
`pensive cardboard and aluminum tubes, including rein(cid:173)
`forcing tube 40 that facilitates the blade heater arrange(cid:173)
`ment. Only small amounts of relatively more expensive
`metals or other conductive materials are used. Heating
`element 10 and tobacco flavor element 60, 80, 90 can
`thus be produced inexpensively enough to be provided
`as disposable items.
`
`EXAMPLES
`Precursor element 50 can "be made from a number of
`variations of the carbon composite material referred to
`above. Example of some of those variations follow.
`EXAMPLE 1
`475 grams of carbon were obtained by baking wheat
`flour in an inert atmosphere at 1000° F. for 12 hours,
`and then jet milling the resulting material four times to
`obtain the desired particle size distribution, with an
`average particle size of about 10 microns. The carbon
`had a volatiles content of about 15% by weight.
`The carbon was blended for approximately 30 min(cid:173)
`utes in a Sigma blade mixer along with the following
`additional components:
`300 grams of phenolic resin (grade SIA86A, Borden
`Chemicals Co., Industrial Resins Division, Louis(cid:173)
`ville, Ky.);
`25 grams of carbon fiber chopped to 0.25 inch (Panex
`grade, Stackpole Corporation, Lowell, Mass.);
`10 grams of methyl cellulose (grade M532, Fisher
`Scientific, Pittsburgh, Pa.);
`25 grams of wheat flour; and
`60 grams of water.
`
`Ex. 2038-0010
`
`

`

`5,353,813
`
`7
`After blending, the mixture was extruded using a
`laboratory ram extruder into 12-inch long rods having
`an outer diameter of 10 mm. The rods were collected
`from the extruder head on U-notched graphite plates
`for ease of processing. The rods were oven dried in air 5
`for three days at 100° F., and then cured in a nitrogen
`atmosphere for 8 hours at 420° F. After curing of the
`rods, the graphite plates with the rods were placed in a
`stainless steel container and continually flushed with
`argon gas. The container was located in an oven and 10
`was baked according to the following cycle:
`1. Raise temperature from 420° F. to 1,950° F. in five
`hours.
`2. Hold temperature at 1,950° F. for five hours.
`3. Cool to room temperature as fast as argon flushing 15
`allows.
`The cooled plates and rods were removed from the
`stainless steel container and the rods were removed
`from the plates. The rods were ground to the shape
`illustrated above.
`The rods were cut and ground, to form the shape
`illustrated above, until each blade had a resistance of
`between about 1.2 n and about 1.5 n. The blade ends
`and surface 66 were coated with gold to reduce contact
`resistance.
`
`8
`with an average particle size of about 10 microns.
`The carbon had a volatiles content of about 15%
`by weight.
`The carbon was blended for approximately 30 min(cid:173)
`utes in a Sigma blade mixer along with the following
`additional components:
`300 grams of phenolic resin (same as above);
`75 grams of carbon fiber chopped to 0.25 inch (same
`as above);
`30 grams of methyl cellulose (same as above);
`25 grams of wheat flour; and
`130 grams of water.
`After blending, the mixture was processed as above.
`EXAMPLES
`500 grams of carbon were obtained by baking wheat
`flour in an inert atmosphere at 1000° F. for 12 hours,
`and then jet milling the resulting material four times to
`obtain the desired particle size distribution, with an
`average particle size of about microns. The carbon had
`a volatiles content of about 15% y weight.
`The carbon was blended for approximately 30 min(cid:173)
`utes in a Sigma blade mixer along with the following
`additional components:
`400 grams of carbon fiber chopped to 0.25 inch (same
`as above); and
`20 grams of methyl cellulose (same as above).
`After blending, the mixture was processed as above.
`Thus it is seen that a heating element and a tobacco
`flavor generating element for an electrical smoking
`article, using an inexpensive tubular array of heater
`blades, is provided. One skilled in the art will appreciate
`that the present invention can be practiced by other
`than the described embodiments, which are presented
`for purposes of illustration and not of limitation, and the
`present invention is limited only by the claims which
`follow.
`What is claimed is:
`1. A heating element of an electrical smoking article,
`said heating element comprising:
`a tubular support member;
`a tubular array of spaced-apart, electrically conduc(cid:173)
`tive blades, said tubular support member received
`concentrically within said tubular array of blades
`and being non-unitary with said tubular array of
`blades;
`a tobacco medium located adjacent said tubular array
`of blades;
`said tubular array of blades including an electrically
`conductive ring portion, each of said blades fixed at
`one end to said ring portion, each of said blades
`including a free end remote from said ring portion;
`a common electrical connection operative at said ring
`portion; and
`a second, electrical connection operative at each of
`said free ends;
`whereby, upon electrical communication of any
`blade to a power source through said common
`electrical connection and a respective second elec(cid:173)
`trical connection, said blade becomes electrically
`heated to produce tobacco flavor from said to(cid:173)
`bacco flavor medium.
`2. The electrical heating element of claim 1, wherein
`said blades cover a greater portion of said tubular sup(cid:173)
`port member than spaces defined between said blades.
`3. The electrical heating element of claim 1, wherein
`said tobacco medium is disposed on said blades.
`
`20
`
`25
`
`40
`
`EXAMPLE2
`450 grams of carbon were obtained by baking wheat
`flour in an inert atmosphere at 600° F. for hours, and
`then jet milling the resulting material four times to ob- 30
`tain the desired particle size distribution, with an aver(cid:173)
`age particle size of about microns. The carbon had a
`volatiles content of about 15% by weight.
`The carbon was blended for approximately minutes
`in a Sigma blade mixer along with the following addi- 35
`tional components:
`300 grams of phenolic resin (same as above);
`50 grams of carbon fiber chopped to 0.25 inch (same
`as above);
`60 grams of methyl cellulose (same as above);
`25 grams of wheat flour; and
`200 grams of water.
`After blending, the mixture was processed as above.
`EXAMPLE3
`475 grams of carbon were obtained by baking wheat
`flour in an inert atmosphere at 1000° F. for 12
`hours, and then jet milling the resulting material
`four times to obtain the desired particle size distri(cid:173)
`bution, with an average particle size of about 10 50
`microns. The carbon had a volatiles content of
`about 15% by weight.
`The carbon was blended for approximately 30 min(cid:173)
`utes in a Sigma blade mixer along with the following
`additional components:
`300 grams of phenolic resin (same as above);
`25 grams of carbon fiber chopped to 0.25 inch (same
`as above);
`20 grams of methyl cellulose (same as above);
`25 grams of