United States Patent [19J
`Hajaligol
`
`[54]
`
`INTERDIGITATED CYLINDRICAL HEATER
`FOR USE IN AN ELECTRICAL SMOKING
`ARTICLE
`
`[75]
`
`Inventor: Mohammad R. Hajaligol, Richmond,
`Va.
`
`[73] Assignee: Philip Morris Incorporated, New
`York, N.Y.
`
`[21] Appl. No.: 333,470
`
`[22] Filed:
`
`Nov. 2, 1994
`
`Related U.S. Application Data
`
`[63] Continuation-in-part of Ser. No. 224,848, Apr. 8, 1994,
`which is a continuation-in-part of Ser. No. 118,665, Sep. 10,
`1993, Pat. No. 5,388,594, which is a continuation-in-part of
`Ser. No. 943,504, Sep. 11, 1992, which is a continuation(cid:173)
`in-part of Ser. No. 666,926, Mar. 11, 1991, abandoned,
`which is a continuation of Ser. No. 12,799, Feb. 2, 1993.
`Int. Cl.6 ................................. HOSB 3/58; A24F 1/22
`[51]
`[52] U.S. Cl •....... , ................... 219/535; 219/553; 131/194
`[58] Field of Search ..................................... ,219/535, 542,
`219/552-553; 131/194, 197; 128/202.21,
`203.27; 338/310, 312, 320; 392/386
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`2/1961 Western .................................. 219/553
`2,971,039
`3/1985 Moritoki ................................. 219/553
`4,503,319
`3/1988 Resce ...................................... 131/194
`4,732,168
`4,788,077 11/1988 Kang .
`5,060,671 10/1991 Counts et al. .......................... 131/329
`3/1992 Losee et al. ............................ 131/194
`5,095,921
`5,157,242 10/1992 Hetherington .......................... 219/553
`7/1993 Deevi et al ..............•.............. 131/194
`5,224,498
`5,235,157
`8/1993 Blackbum ............................... 219/268
`5,249,586 10/1993 Morgan ................•..•.•........ 128/203.27
`5,274,214 12/1993 Blackburn ............................... 219/268
`5,285,050
`2/1994 Blackbum ............................... 219/268
`6/1994 Deevi et al ..
`5,322,075
`5,353,813 10/1994 Deevi ...................................... 219/553
`5,388,594
`2/1995 Counts ............................... 128/203.27
`
`I 1111111111111111 11111 111111111111111 IIIII 111111111111111 111111111111111111
`US005530225A
`[lll Patent Number:
`[ 45] Date of Patent:
`
`5,530,225
`Jun.25,1996.
`
`OTHER PUBLICATIONS
`
`Amin "Arc Spray Coatings Using Inert Gases," TWI Bul(cid:173)
`letin 6, pp. 129-132, Nov./Dec. 1992.
`Blunt et al, "High Velocity Spraying for Electronic Sub(cid:173)
`strates," TWI Connect-World Centre for Materials Joining
`Technology, No. 40, Dec. 1992.
`Filmer et al, "Plasma Spray Deposition of Alumina-Based
`Ceramic," Ceramic Bulletin, vol. 69, No. 12, pp.
`1955-1958, 1990.
`Herman, "Coatings and Coating Practices," Advanced Mate(cid:173)
`rials & Processes, pp. 59-60, 84-85, Jan. 1990. ·
`Herman, "Plasma-Sprayed Coatings," Scientific American,
`pp. 112-116, 1988.
`Herman, ''Plasma Spray Deposition Processes," MRS Bul(cid:173)
`letin, pp. 60-67, 1988.
`Sampath et al, "Microstructure and Properties of Plas(cid:173)
`ma-Spray Consolidated/l'wo-Phase Nickel Aluminides,"
`vol. 25, pp. 1425-1430, 1991.
`
`(List continued on next page.)
`
`Primary Examiner-Teresa J. Walberg
`Assistant Examiner-Sam Paik
`Attorney, Agent, or Firm-Kevin B. Osborne; James E.
`Schardt; Charles E. B. Glenn
`
`[57]
`
`ABSTRACT
`A heater having a generally cylindrical or tubular configu(cid:173)
`ration comprised of a selected plurality of thermally con(cid:173)
`ductive heater blades and adjacent heat sink and aerosol
`barrier blades interposed between the heater blades to form
`an interdigitated structure. A respective gap is defined
`between a heater blade and an adjacent heat sink blade to
`prevent heat loss during an electrical pulse which heats the
`heater blade. During the subsequent cooling period and puff
`interval, the adjacent heat sink blades prevent heat from
`propagating to other parts of the aerosol generating tube, i.e.,
`the cigarette. In addition to .the thermal function, the barrier
`blades also block the escape of moisture generated by the
`aerosol generating medium, thereby limiting the propagation
`of condensation. The respective gaps between the interdigi(cid:173)
`tated blades are defined to be wide enough to prevent heat
`losses during pulsing from a heater blade to adjacent blades
`yet small enough to prevent escape of significant amounts of
`vapor.
`
`49 Claims, 12 Drawing Sheets
`
`llO
`
`Ex. 2010-0001
`
`

`

`5,530,225
`Page 2
`
`OTHER PUBLICATIONS
`
`Sampath et al, "Structure and Properties of Vacuum Plasma
`Sprayed Hard Coatings," Memories et Etudes Scientifiques
`Revue de Metallurgie, pp. 289-294, Mai 1991.
`Srivatsan et al, "Review Use of Spray Techniques to Syn(cid:173)
`thesize Particulate-Reinforced Metal-Matrix Composites,"
`Journal of Materials Science 27, pp. 5965-5981, 1992.
`Street et al, ''Trends In Laser Cutting of Advanced Materi(cid:173)
`als," TWI Bulletin 5, pp. 108-111, Sep./Oct. 1992.
`Tiwari et al, Spray Forming of MoSi2 and MoSi2-Based
`Composites, Mat. Res. Soc. Symp. Proc., vol. 213, Materials
`Research Society, pp. 807-813, 1991.
`Tiwari et al, '"Thermal Spray Forming of Particulate Com(cid:173)
`posites," Dept. of Mat. Sci. & Engineering, State University
`of New York, Stony Brook, NY 11794-2275 and Flame
`Spray Industries, Inc., 152 Haven Ave., Port Washington,
`NY 11050.
`Tiwari et al, "Incorporating of Reinforcements in Spray
`Formed MMCs", Department of Materials Science and
`Engineering, State University of New York, Stony Brook,
`NY 11794-2275.
`Travis, "Making Materials That Are Good to the Last Drop,"
`Research News, vol. 258, p. 1307, Nov. 1992.
`Wang et al, "Activation Energy for Crystal Growth Using
`Isothermal and Continuous Heating Processes", Journal of
`Materials Science, Chapman and Hall, vol. 25, pp.
`2339-2343, 1990.
`
`''Thermomechanical Properties of Plas(cid:173)
`Wang et al,
`ma-Sprayed Oxides in the Mg0-Al2O3-SiO2 system," Sur(cid:173)
`face and Coatings Technology, vol. 42, pp. 203-216, 1990.
`Wu et al, "Heat Transfer to a Particle in a Thermal Plasma,"
`Trans IChemE, vol. 69, Part A, pp. 21-24, Jan. 1991.
`Zaat, "A Quarter of a Century of Plasma Spraying," Ann
`Rev. Mater. Sci.by Annual Reviews, Inc., pp. 13:9,-42, 1983.
`Zatorski et al, "Wear of Plasma-Sprayed Alumina-Titania
`Coatings," High Performance Ceramic Films and Coatings
`by Elsevier Science Publishers B. V., pp., 591-601, 1991.
`Fen et al., "Cyclic Oxidation of Haynes 230 alloy," Chap(cid:173)
`man & Hall, pp. 1514-1520 (1992).
`Reinshagen and Sikka, "Thermal Spraying of Selected Alu(cid:173)
`minides," Proceedings of the Fourth National Thermal
`Spray Conference, Pittsburgh, PA, USA, pp. 307-313, (4-10
`May 1991).
`Kutner,
`'"Thermal Spray by Design," Reprint from
`Advanced Materials & Processes incorporating Metal
`Progress, Oct. (1988).
`"Characterizing THERMAL SPRAY COATINGS," article
`based on presentations made at the fourth National Thermal
`Spray Conference, 4-10 May (1991) and which appeared in
`"Advanced Materials and Processes," May 1992, pp. 23-27.
`Howes, Jr., "Computerized Plasma Control for Applying
`Medical-Quality Coatings," Industrial Heating, pp. 22-25,
`Aug., 1993.
`
`Ex. 2010-0002
`
`

`

`U.S. Patent
`US. Patent
`
`Jun.25, 1996
`Jun. 25, 1996
`
`Sheet 1 of 12
`Sheet 1 of 12
`
`5,530,225
`5,530,225
`
`
`
`C''J
`('J
`
`~-j
`
`Ex. 2010-0003
`
`Ex. 2010-0003
`
`

`

`US. Patent
`U.S. Patent
`
`Jun. 25, 1996
`Jun.25, 1996
`
`Sheet 2 of 12
`Sheet 2 of 12
`
`5,530,225
`5,530,225
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`Fig. 2
`Fig. 2
`
`Ex. 2010-0004
`
`Ex. 2010-0004
`
`

`

`U.S. Patent
`
`Jun. 25, 1996
`
`Sheet 3 of 12
`
`5,530,225
`
`122
`
`210
`
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`
`Fig. 6
`
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`
`Ex. 2010-0005
`
`

`

`U.S. Patent
`
`Jun.25, 1996
`
`Sheet 4 of 12
`
`5,530,225
`
`220
`
`200
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`
`110
`
`220
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`120
`
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`CR
`
`124
`
`Fig. 4B
`
`Ex. 2010-0006
`
`

`

`U.S. Patent
`
`Jun.25, 1996
`
`Sheet 5 of 12
`
`5,530,225
`
`220
`
`200
`
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`
`126
`
`110
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`120
`
`Fig. 4C
`
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`
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`
`130
`
`CR
`
`Fig. 4D
`
`Ex. 2010-0007
`
`

`

`U.S. Patent
`
`Jun.25, 1996
`
`Sheet 6 of 12
`
`5,530,225
`
`128
`
`122
`
`130
`
`120
`
`220
`
`220
`
`t20
`
`Fig. 5
`
`Ex. 2010-0008
`
`

`

`US. Patent
`U.S. Patent
`
`Jun. 25, 1996
`Jun.2S,1996
`
`Sheet 7 of 12
`Sheet 7 of 12
`
`5,530,225
`5,530,225
`
`128
`128
`
`122
`
`130
`
`120
`
`
`
`130
`
`120
`
`Fig. 7
`Fig. 7
`
`Ex. 2010-0009
`
`Ex. 2010-0009
`
`

`

`U.S. Patent
`US. Patent
`
`Jun. 25, 1996
`Jun. 25, 1996
`
`Sheet 8 of 12
`Sheet 8 of 12
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`5,530,225
`5,530,225
`
`188
`
`810
`
`124
`
`360
`
`135
`
`Fig. BA
`
`Ex. 2010-0010
`
`Ex. 2010-0010
`
`

`

`U.S. Patent
`US. Patent
`
`Jun. 25, 1996
`Jun.25,1996
`
`Sheet 9 of 12
`Sheet 9 of 12
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`5,530,225
`5,530,225
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`128
`/188
`
`220
`
`E310
`
`135
`
`FIG. 8B
`FIG. 8B
`
`EX. 2010-0011
`
`Ex. 2010-0011
`
`

`

`U.S. Patent
`US. Patent
`
`Jun. 25, 1996
`Jun. 25, 1996
`
`Sheet 10 of 12
`Sheet 10 of 12
`
`5,530,225
`5,530,225
`
` 1
`
`122A
`
`Fig. 9
`Fig. 9
`
`EX. 2010-0012
`
`Ex. 2010-0012
`
`

`

`U.S. Patent
`US. Patent
`
`Jun.25, 1996
`Jun. 25, 1996
`
`Sheet 11 of 12
`Sheet 11 of 12
`
`5,530,225
`5,530,225
`
`10
`
`
`
`Ex. 2010-0013
`
`Ex. 2010-0013
`
`

`

`U.S. Patent
`US. Patent
`
`\-
`
`Jun. 25, 1996
`Jun.25, 1996
`
`Sheet 12 of 12
`Sheet 12 of 12
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`5,530,225
`5,530,225
`
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`Ex. 2010-0014
`
`

`

`5,530,225
`
`1
`INTERDIGITATED CYLINDRICAL HEATER
`FOR USE IN AN ELECTRICAL SMOKING
`ARTICLE
`
`Cross Reference to Related Applications
`The present application is a continuation-in-part of com(cid:173)
`monly assigned patent application Ser. No. 08/224,848, filed
`Apr. 8, 1994, entitled "Tubular Heater for Use in an Elec(cid:173)
`trical Smoking Article" which is a continuation-in-part of
`patent application Ser. No. 08/118,665, filed Sep. 10, 1993,
`now U.S. Pat. No. 5,388,594 which in tum is a continuation(cid:173)
`in-part of commonly assigned patent application No. 07 /943,
`504, filed Sep. 11, 1992, which in tum is a continuation-in(cid:173)
`part of patent application Ser. No. 07 /666,926 filed Mar. 11,
`1991, now abandoned in favor of filewrappper continuation
`application Ser. No. 08/012,799 filed Feb. 2, 1993. The
`present application also relates to commonly assigned
`copending patent application Ser. No. 07/943,747, filed Sep.
`11, 1992 and to commonly assigned U.S. Pat. No. 5,060,671,
`issued Oct. 29, 1991; U.S. Pat. No. 5,095,921, issued Mar.
`17, 1992; and U.S. Pat. No. 5,224,498, issued Jul. 6, 1992;
`which are hereby incorporated by reference.
`
`BACKGROUND OF THE INVENTION
`
`1. Technical Field of the Invention
`Previously known conventional smoking devices deliver
`flavor and aroma to the user as a result of combustion of
`tobacco. A mass of combustible material, primarily tobacco,
`is oxidized as the result of applied heat with typical com(cid:173)
`bustion temperatures in a conventional cigarette being in
`excess of 800° C. during puffing. Heat is drawn through an
`adjacent mass of tobacco by drawing on the mouth end.
`During this heating, inefficient oxidation of the combustible
`material takes place and yields various distillation and
`pyrolysis products. As these products are drawn through the
`body of the smoking device toward the mouth of the user,
`they cool and condense to form an aerosol or vapor which
`gives the consumer the flavor and aroma associated with
`smoking.
`Conventional cigarettes have various perceived draw(cid:173)
`backs associated with them. Among them is the production
`of sidestream smoke during smoldering between puffs,
`which may be objectionable to some nonsmokers. Also,
`once lit, they must be fully consumed or be discarded.
`Relighting a conventional cigarette is possible but is usually
`an unattractive prospect for subjective reasons (flavor, taste,
`odor) to a discerning smoker.
`A prior alternative to the more conventional cigarettes
`include those in which the combustible material itself does
`not directly provide the flavorants to the aerosol inhaled by
`the smoker. In these smoking articles, a combustible heating
`element, typically carbonaceous in nature, is combusted to
`heat air as it is drawn over the heating element and through
`a zone which contains heat-activated elements that release a
`flavored aerosol. While this type of smoking device pro(cid:173)
`duces little or no sidestream smoke, it still generates prod(cid:173)
`ucts of combustion, and once lit it is not adapted to be
`snuffed for future use in the conventional sense.
`In both the more conventional and carbon element heated
`smoking devices described above combustion takes place
`during their use. This process naturally gives rise to many
`byproducts as the combusted material breaks down and
`interacts with the surrounding atmosphere.
`Commonly assigned U.S. Pat. Nos. 5,093,894; 5,225,498;
`5,060,671 and 5,095,921 disclose various electrical resistive
`
`2
`heating elements and flavor generating articles which sig(cid:173)
`nificantly reduce sidestream smoke while permitting the
`smoker to selectively suspend and reinitiate smoking. How(cid:173)
`ever, the cigarette articles disclosed in these patents are not
`5 very durable and may collapse, tear or break from extended
`or heavy handling. In certain circumstances, these prior
`cigarette articles may crush as they are inserted into the
`electric lighters. Once they are smoked, they are even
`weaker and may tear or break as they are removed from the
`lighter.
`U.S. patent application Ser. No. 08/118,665, filed Sep. 10,
`1993, describes an electrical smoking system including a
`novel electrically powered lighter and novel cigarette that is
`adapted to cooperate with the lighter. The preferred embodi(cid:173)
`ment of the lighter includes a plurality of metallic sinusoidal
`15 heaters disposed in a configuration that slidingly receives a
`tobacco rod portion of the cigarette.
`The preferred embodiment of the cigarette of Ser. No.
`08/118,665 preferably comprises a tobacco-laden tubular
`20 carrier, cigarette paper overwrapped about the tubular car(cid:173)
`rier, an arrangement of flow-through filter plugs at a mouth(cid:173)
`piece end of the carrier and a filter plug at the opposite
`(distal) end of the carrier, which preferably limits air flow
`axially through the cigarette. The cigarette and the lighter
`are configured such that when the cigarette is inserted into
`the lighter and as individual heaters are activated for each
`puff, localized charring occurs at spots about the cigarette in
`the locality where each heater was bearing against the
`cigarette. Once all the heaters have been activated, these
`
`10
`
`25
`
`30 ~!:;~ sfo~!n!~ ~~:~n s~;c~~ f~::e;n;o:i::f ~~
`
`35
`
`40
`
`45
`
`50
`
`cigarette. Depending on the maximum temperatures and
`total energies delivered at the heaters, the charred spots
`manifest more than mere discolorations of the cigarette
`paper. In most applications, the charring will create at least
`minute breaks in the cigarette paper and the underlying
`carrier material, which breaks tends to mechanically weaken
`the cigarette. For the cigarette to be withdrawn from the
`lighter, the charred spots must be at least partially slid past
`the heaters. In aggravated circumstances, such as when the
`cigarette is wet or toyed with or twisted, the cigarette may
`be prone to break or leave pieces upon its withdrawal from
`the lighter. Pieces left in the lighter fixture can interfere with
`the proper operation of the lighter and/or deliver an off-taste
`to the smoke of the next cigarette. If the cigarette breaks in
`two while being withdrawn, the smoker may be faced not
`only with the frustration of failed cigarette product, but also
`with the prospect of clearing debris from a clogged lighter
`before he or she can enjoy another cigarette.
`The preferred embodiment of the cigarette of Ser. No.
`08/118,665 is essentially a hollow tube between the filter
`plugs at the mouthpiece end of the cigarette and the plug at
`the distal end. This construction is believed to elevate
`delivery to the smoker by providing sufficient space into
`55 which aerosol can evolve off the carrier with minimal
`impingement and condensation of the aerosol on any nearby
`surfaces.
`Several proposals have been advanced which significantly
`reduce undesired sidestream smoke while permitting the
`60 smoker to suspend smoking of the article for a desired period
`and then to resume smoking. For example, commonly
`assigned U.S. Pat. Nos. 5,093,894; 5,225,498; 5,060,671
`and 5,095,921 disclose various heating elements and flavor
`generating articles. Grandparent application Ser. No. 08/118,
`65 665 discloses an electrical smoking article having heaters
`which are actuated upon sensing of a draw by control and
`logic circuitry. The heaters are preferably a relatively thin
`
`Ex. 2010-0015
`
`

`

`5,530,225
`
`4
`SUMMARY OF THE INVENTION
`
`3
`serpentine structure to transfer adequate amounts of heat to
`the cigarette and is lightweight.
`Although these devices and heaters overcome the
`observed problems and achieve the stated objectives, many
`embodiments are plagued by the formation of a significant
`amount of condensation formed as the tobacco flavor
`medium is heated to form vapors. These vapors can cause
`problems as they condense on relatively cooler various
`electrical contacts and the associated control and logic
`circuitry. In addition, condensation can influence the sub(cid:173)
`jective flavor of the tobacco medium of the cigarette.
`Though not desiring to be bound by theory, it is believed that
`the condensation is the result of the flow pattern and pressure
`gradient of ambient air drawn through the article and the
`current designs of the heater assemblies. The heating of the
`tobacco flavor medium releases vapors which are then
`cooled to result in condensation on the surfaces of relatively
`cooler components. The condensation can cause shorting
`and other undesired malfunctions.
`In addition, the proposed heaters are subject to mechani(cid:173)
`cal weakening and possible failure due to stresses induced
`by inserting and removing the cylindrical tobacco medium
`and also by adjusting or toying with the inserted cigarette.
`Also, the electrical smoking articles employ electrically 25
`resistive heaters which have necessitated relatively complex
`electrical connections which can be disturbed by insertion
`and removal of the cigarette.
`
`OBJECTS OF THE INVENTION
`
`20
`
`The foregoing and additional objects are obtained by a
`heater according to the present invention. The heater has a
`5 generally cylindrical or tubular configuration comprised of a
`selected plurality of thermally conductive heater blades
`bearing heaters and a plurality of adjacent heat sink(cid:173)
`aerosol barrier blades interposed between the heater blades
`to form an interdigitated structure. A respective gap is
`10 defined between a heater blade and an adjacent heat sink
`blade to prevent heat loss during an electrical pulse which
`heats the heater disposed on the heater blade. During the
`subsequent c9oling period and puff interval, the adjacent
`heat sink blades prevent heat from propagating to other parts
`15 of the aerosol generating tube, i.e., the cigarette. In addition
`to the thermal insulating function, the barrier blades also
`block the escape of moisture generated by the aerosol
`generating medium, thereby limiting the propagation of
`condensation. The respective gaps between the interdigi-
`tated blades are defined to be wide enough to prevent heat
`losses during pulsing from a heater blade to adjacent blades
`and associated portion of the cigarette and to permit a
`transverse air flow, yet small enough to prevent escape of
`significant amounts of vapor.
`This heater structure according to the present invention is
`fabricated by a number of methods. One method includes
`cutting a thermally insulating ceramic tube into two mating
`pieces, each piece having a plurality of blades. The blades of
`one piece are configured as heaters by depositing a heating
`30 material and leads thereon. Alternatively, the heating ele(cid:173)
`ment piece is made by cutting blades from a sheet and
`rolling the cut sheet into a cylinder for mating with the
`ceramic piece having heat sink blades. In another embodi(cid:173)
`ment, a ceramic tube is cut axially to form a plurality of
`discrete areas of blades with a single, and optionally a
`second, hub at an end of the tube. Alternate discrete areas are
`deposited with a conductive heating material. The inter(cid:173)
`posed areas are used as heat sinks and aerosol barriers and
`may also serve as part of the electrical conduction path.
`40 Alternatively, the ceramic tube is cut axially to form a
`desired number of heat sink-aerosol barrier blades with
`interposed slots. Heater elements are then cut and suspended
`in the respective slots.
`
`It is accordingly an object of the present invention to
`provide a heater which generates smoke from a tobacco
`medium without sustained combustion.
`It is another object of the present invention to provide a 35
`heater for a smoking article which reduces the creation of
`undesired sidestream smoke.
`It is yet another object of the present invention to provide
`a heater for a smoking article which permits the smoker to
`suspend and resume use.
`It is a further object of the present invention to accomplish
`the foregoing objects while reducing aerosol or smoke
`condensation within the smoking article.
`It is yet another object of the present invention to provide 45
`a heater structure which provides a desired number of puffs
`and which is straightwardly modified to change the number
`and or duration of puffs provided without sacrificing sub(cid:173)
`jective qualities of the tobacco.
`It is another object of the present invention to provide a 50
`method of making such a heater to accomplish the foregoing
`objects.
`It is a further object of the present invention to provide a
`heating element for a smoking article which is mechanically
`suitable for insertion and removal of a cigarette.
`It is another object of the present invention to simplify
`connections of an electrically resistive heater to an associ(cid:173)
`ated power source.
`It is a further object of the present invention to provide
`such a heater which is more economical to manufacture.
`It is another object of the present invention to accomplish
`the foregoing objects simply and in a straightforward man(cid:173)
`ner.
`Additional objects and advantages of the present inven(cid:173)
`tion are apparent from the drawings and specification which
`follow.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`55
`
`FIG. 1 is a partially exposed perspective view of a
`smoking article employing a heater according to the present
`invention;
`FIG. 2 is a side, cross-sectional view of a cigarette used
`in conjunction with the present invention;
`FIG. 3 is a side, cross-sectional view of a heater fixture
`according to the present invention;
`FIG. 4A is a perspective view of a barrier component and
`a heater component according to an embodiment of the
`present invention;
`FIG. 4B is a perspective view of the components of FIG.
`4A interposed to form a receptacle for an inserted cigarette;
`FIG. 4C is a perspective view of a heater component and
`a barrier component according to another embodiment of the
`present invention;
`FIG. 4D is a perspective view of the components of FIG.
`65 4C interposed to form a receptacle for an inserted cigarette;
`FIG. 5 is a perspective view of a heater according to
`another embodiment of the present invention having a single
`
`60
`
`Ex. 2010-0016
`
`

`

`5,530,225
`
`5
`hub and a plurality of alternating heater blades and differ(cid:173)
`ently sized barrier blades;
`FIG. 6 is a side, cross-sectional view of an embodiment of
`the present invention;
`FIG. 7 is a perspective view of an embodiment of the
`present invention employing a plurality of heater blades
`extending from a single hub;
`FIGS. SA and SB are perspective views of an monolithic
`embodiment having rectangular and rounded gaps and two 10
`end hubs;
`FIG. 9 is a perspective view of an embodiment of the
`present invention wherein slots are defined for insulated
`heaters;
`FIG. 10 is a perspective view of a heater cutout prior to
`rolling; and
`FIG. 11 is an elevational view of a serpentine-shaped
`heater element according to the present invention which is
`inserted into the slots of FIG. 9.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`A smoking system 21 according to the present invention
`is generally seen with reference to FIGS. 1 and 2. The
`smoking system 21 includes a cylindrical aerosol generating
`tube or cigarette 23 and a reusable lighter 25. The cigarette
`23 is adapted to be inserted in and removed from an orifice
`27 at a front end 29 of the lighter 25. The smoking system
`21 is used in much the same fashion as a conventional
`cigarette. The cigarette 23 is disposed of after one or more
`puff cycles. The lighter 25 is preferably disposed of after a
`greater number of puff cycles than the cigarette 23.
`The lighter 25 includes a housing 31 and has front and
`rear portions 33 and 35. A power source 37 for supplying
`energy to heating elements for heating the cigarette 23 is
`preferably disposed in the rear portion 35 of the lighter 25.
`The rear portion 35 is preferably adapted to be easily opened
`and closed, such as with screws or with snap-fit components,
`to facilitate replacement of the power source 37. The front
`portion 33 preferably houses heating elements and circuitry
`in electrical communication with the power source 37 in the
`rear portion 35. The front portion 33 is preferably easily
`joined to the rear portion 35, such as with a dovetail joint or
`by a socket fit. The housing 31 is preferably made from a
`hard, heat-resistant material. Preferred materials include
`metal-based or, more preferably, polymer-based materials.
`The housing 31 is preferably adapted to fit comfortably in
`the hand of a smoker and, in a presently preferred embodi(cid:173)
`ment, has overall dimensions of 10.7 cm by 3.8 cm by 1.5
`cm.
`The power source 37 is sized to provide sufficient power
`for heating elements that heat the cigarette 23. The power
`source 37 is preferably replaceable and rechargeable and
`may include devices such as a capacitor, or more preferably,
`a battery. In a presently preferred embodiment, the power
`source is a replaceable, rechargeable battery such as four
`nickel cadmium battery cells connected in series with a total,
`non-loaded voltage of approximately 4.8 to 5.6 volts. The
`characteristics required of the power source 37 are, however,
`selected in view of the characteristics of other components
`in the smoking system 21, particularly the characteristics of
`the heating elements. U.S. Pat. No. 5,144,962 describes
`several forms of power sources useful in connection with the
`smoking system of the present invention, such as recharge(cid:173)
`able battery sources and quick-discharging capacitor power
`
`6
`sources that are charged by batteries, and is hereby incor(cid:173)
`porated by reference.
`A substantially cylindrical heating fixture 39 for heating
`the cigarette 23, and, preferably, for holding the cigarette in
`5 place relative to the lighter 25, and electrical control cir(cid:173)
`cuitry 41 for delivering a predetermined amount of energy
`from the power source 37 to heating elements (not seen in
`FIGS. 1 and 2) of the heating fixture are preferably disposed
`in the front 33 of the lighter. As described in greater detail
`below, a generally circular, terminal end hub 110 is fixed,
`e.g., welded, to be disposed within the interior of heater
`fixture 39, e.g., is fixed to spacer 49, as shown in FIG. 3. If
`the heater has two end hubs, either hub can serve as the fixed
`terminal end. In the presently preferred embodiment, the
`15 heating fixture 39 includes a plurality of radially spaced
`heating elements 122 supported to extend from the hub, seen
`in FIG. 3 and described in greater detail below, that are
`individually energized by the power source 37 under the
`control of the circuitry 41 to heat a number of, e.g., eight,
`20 areas around the periphery of the inserted cigarette 23. Eight
`heating elements 122 are preferred to develop eight puffs as
`in a conventional cigarette and eight heater elements also
`lend themselves to electrical control with binary devices. A
`desired number of puffs can be generated, e.g., any number
`25 between 5-16, and preferably 6-10 or 8 per inserted ciga(cid:173)
`rette. As discussed below, the number of heaters can exceed
`the desired number of puffs/cigar
`The circuitry 41 is preferably activated by a puff-actuated
`sensor 45, seen in FIG. 1, that is sensitive either to pressure
`30 drops that occur when a smoker draws on the cigarette 23.
`The puff-actuated sensor 45 is preferably disposed in the
`front 33 of the lighter 25 and communicates with a space
`inside the heater fixture 39 and near the cigarette 23 through
`a passageway extending through a spacer and a base of the
`35 heater fixture and, if desired, a puff sensor tube (not shown).
`A puff-actuated sensor 45 suitable for use in the smoking
`system 21 is described in U.S. Pat. No. 5,060,671, the
`disclosure of which is incorporated by reference, and is in
`the form of a Model 163PCOID35 silicon sensor, manufac-
`tured by the MicroSwitch division of Honeywell, Inc.,
`Freeport, Ill., which activates an appropriate one of the
`heater elements 122 as a result of a change in pressure when
`a smoker draws on the cigarette 23. Flow sensing devices,
`such as those using hot-wire anemometry principles, have
`45 also been successfully demonstrated to be useful for acti(cid:173)
`vating an appropriate one of the heater elements 122 upon
`detection of a change in air flow.
`An indicator 51 is preferably provided on the exterior of
`the lighter 25, preferably on the front 33, to indicate the
`50 number of puffs remaining on a cigarette 23 inserted in the
`lighter. The indicator 51 preferably includes a seven-seg(cid:173)
`ment liquid crystal display. In a presently preferred embodi(cid:173)
`ment, the indicator 51 displays the digit "8" for use with an
`eight-puff cigarette when a light beam emitted by a light
`55 sensor 53, seen in FIG. 1, is reflected off of the front of a
`newly inserted cigarette 23 and detected by the light sensor.
`The light sensor 53 is preferably mounted in an opening in
`the spacer and the base of the heater fixture 39. The light
`sensor 53 provides a signal to the circuitry 41 which, in tum,
`60 provides a signal to the indicator 51. For example, the
`display of the digit "8" on the indicator 51 reflects that the
`preferred eight puffs provided on each cigarette 23 are
`available, i.e., none of the heater elements 43 have been
`activated to heat the new cigarette. After the cigarette 23 is
`fully smoked, the indicator displays the digit "0". When the
`cigarette 23 is removed from the lighter 25, the light sensor
`53 does not detect the presence of a cigarette 23 and the
`
`40
`
`65
`
`Ex. 2010-0017
`
`

`

`5,530,225
`
`7
`indicator 51 is turned off. The light sensor 53 is modulated
`so that it does not constantly emit a light beam and provide
`an unnecessary drain on the power source 37. A presently
`preferred light sensor 53 suitable for use with the smoking
`system 21 is a Type OPR5005 Light Sensor, manufactured
`by OPTEX Technology, Inc., 1215 West Crosby Road,
`Carrollton, Tex. 75006.
`As one of several possible alternatives to using the
`above-noted light sensor 53, a mechanical switch (not
`shown) may be provided to detect the presence or absence
`of a cigarette 23 and a reset button (not shown) may be
`provided for resetting the circuitry 41 when a new cigarette
`is inserted in the lighter 25, e.g., to cause the indicator 51 to
`display the digit "8", etc. Power sources, circuitry, puff(cid:173)
`actuated sensors, and indicators useful with the smoking
`system 21 of the present invention are described in U.S. Pat.
`No. 5,060,671 and U.S. patent application Ser. No. 07/943,
`504, both of which are incorporated by reference. The
`passageway and the opening 50 in the spacer and the heater
`fixture base are preferably air-tight during smoking.
`A presently preferred cigarette 23 for use with the smok(cid:173)
`ing system 21 will now be described and is shown in greater
`detail in grandparent application Ser. No. 08/118,665,
`although the cigarette may be in any desired form capable of
`generating a flavored tobacco response for delivery to a
`smoker when the cigarette is heated by the heat