Electrical smoking system and method

Information

  • Patent Grant
  • 6688313
  • Patent Number
    6,688,313
  • Date Filed
    Friday, March 23, 2001
    23 years ago
  • Date Issued
    Tuesday, February 10, 2004
    20 years ago
Abstract
An electrical smoking system comprising a cigarette and an electric lighter, wherein the cigarette comprises a tubular tobacco mat partially filled with material tobacco so as to define a filled tobacco rod portion and an unfilled tobacco rod portion. The cigarette and the lighter are mutually arranged so that when the cigarette is received in the lighter, the electrical heater element of the lighter at least partially superposes at least a portion of the filled tobacco rod portion. The cigarette and the lighter are also mutually arranged so that when the cigarette is received in the lighter, the free end of the cigarette is occluded. The cigarette includes a zone of perforations at a location along the filled tobacco rod portion, with the cigarette being free of perforations along the unfilled tobacco rod portion. An apparatus for perforating a cigarette which can be smoked in an electrical smoking device includes a drum link-up assembly and a laser perforating apparatus. The apparatus can be used in a method of perforating a tobacco rod of the cigarette prior to assembly of the tobacco rod to a filter rod via tipping paper. In the method, a tobacco rod is supplied to the drum link-up assembly wherein the tobacco rod is moved from a combining apparatus to a tipping apparatus which attaches the tobacco rod to a filter rod by tipping paper. In making the cigarettes with a tobacco rod and a filter rod, a combining apparatus forms a continuous tobacco rod which is cut into 2-up tobacco rods.
Description




FIELD OF INVENTION




The present invention relates to electrical smoking systems and methods of increasing delivery in electrical smoking systems.




BACKGROUND OF INVENTION




Traditional cigarettes are consumed by lighting an end of a wrapped tobacco rod and drawing air predominately through the lit end by suction at a mouthpiece end of the cigarette. Traditional cigarettes deliver smoke as a result of combustion, during which a mass of tobacco is combusted at temperatures which often exceeds 800° C. during a puff. The heat of combustion releases various gaseous combustion products and distillates from the tobacco. As these gaseous products are drawn through the cigarette, they cool and condense to form a smoke containing the tastes and aromas associated with smoking. Traditional cigarettes produce sidestream smoke during smoldering between puffs. Once lit, they must be fully consumed or be discarded. Relighting a traditional cigarette is possible but is usually an unattractive proposition to a discerning smoker for subjective reasons (flavor, taste, odor).




In an electrical smoking system, it is desirable to deliver smoke in a manner that meets the smokers experiences with more traditional cigarettes, such as an immediacy response (smoke delivery occurring immediately upon draw), a desired level of delivery (which correlates with FTC tar level), together with a desired resistance to draw (RTD) and consistency from puff to puff and from cigarette to cigarette.




Commonly assigned U.S. Pat. Nos. 5,388,594 and 5,692,525 disclose electrical smoking systems and methods of manufacturing a cigarette, which patents are incorporated by reference. The former patent describes an electrical smoking system including a novel electrically powered lighter and a novel cigarette that cooperates with the lighter. The preferred embodiment of the lighter therein included a plurality of metallic serpentine heaters disposed in a configuration that slidingly receives a tobacco rod portion of the cigarette. The preferred embodiment of the cigarette therein comprised a tobacco-laden tubular carrier, a cigarette paper overwrapped about the tubular carrier, an arrangement of flow-through filter plugs at a mouthpiece end of the carrier and a filter plug at the free (distal) end of the carrier. The cigarette and the lighter were configured such that when the cigarette is inserted into the lighter and as individual heaters are actuated for each puff, localized charring occurs at spots about the cigarette in the locality where each heater was bearing against the cigarette (hereinafter referred to as a “heater footprint” or “char zones”). Once all the heaters had been actuated, the cigarette is discarded.




In the latter patent, the cigarette includes a tobacco plug and the cigarette and the heater fixture are mutually configured such that the heater footprints (char zones) at least partially overlap the tobacco plug as well as a hollow portion of the tobacco rod. Such arrangement provides an immediacy of response from the early initiation of pyrolysis at the void, together with inclusion of a fuller flavor contribution from the plug of tobacco(s).




It has been desirous to produce an electrical smoking system of the type described above that produces delivery levels of substantially greater than 3 milligrams tar (FTC). A greater segment of smokers prefer the higher levels of delivery from their more traditional cigarettes of choice. Obtaining such levels of delivery in electrical smoking systems has heretofore been a challenging proposition.




For example, the previously described electrical smoking systems are battery operated, so that the total energy expended per puff needs to be kept at acceptable levels. Too much power application in the heater elements during a puff can lead to burn-throughs and sometimes undesired degrees of combustion.




In systems such as taught in commonly assigned U.S. Pat. No. 5,692,525, in which heater footprints (char zones) at least partially overlap a hollow portion of the tobacco rod and partially overlap a tobacco plug, burn-throughs will usually first appear in the region of the hollow portion of the tobacco rod. Upon such occurrence, the smoke tends to be hotter than the other puffs, with less contribution of the fuller flavor usually generated by the heating of the tobacco plug portion of the cigarette rod. Consistency in the smoking experience are compromised if burn-throughs are not somehow avoided.




In commonly assigned U.S. Pat. No. 5,388,594, the smoked portion of the tobacco rod is preferably entirely hollow and the heater footprint is entirely superposed over a the hollow portion of the tobacco rod. Burn-throughs in the “wholly hollow” system of U.S. Pat. No. 5,388,594 tend to make the smoke all the more hot and/or harsh tasting. Providing expedients to increase delivery in the “wholly hollow” system of U.S. Pat. No. 5,388,594, such as providing perforations as suggested at column 10, lines 36-51 thereof, aggravate the risks of burn-throughs, with adverse consequences upon taste and consistency.




Resistance to draw (RTD) of traditional cigarettes is the pressure required to force air through the full length of a cigarette at the rate of 17.5 ml per second. RTD is usually expressed in inches or millimeter of water. Smokers have certain expectations when drawing upon a traditional cigarette in that too little RTD or too much can detract from smoking enjoyment. More traditional cigarettes of moderate delivery have RTD's generally within the range of approximately 100 to 130 mm water.




Establishing a desired RTD in electrical smoking systems is complicated by the circumstance that in smoking systems such as shown in U.S. Pat. Nos. 5,388,594 and 5,692,525, air is first drawn through passages within the cigarette lighter before being drawn out through the cigarette. The filter tipping of the cigarettes of those systems are preferably flow-through and/or low particulate efficiency filters so as to minimize loss of whatever smoke is produced. Such filters produce little pressure drop and therefore do not contribute much RTD. Consequently, prior practices have included the establishment of RTD (or pressure drop) predominantly in the lighter portion of the electrical smoking system, such as with an annular frit (porous body) adjacent the air admission port of the lighter as taught in commonly assigned U.S. Pat. No. 5,954,979. Because pressure drop varies widely with any change in size of the constriction, it has been found that the use of frits or other forms of tiny flow constrictions in the lighter body must be manufactured with care. It therefore adds expense and other production and quality concerns. Furthermore, tiny flow passages are prone to clog, particularly in lighters wherein any smoke is allowed to linger after completion of a puff.




OBJECTS AND SUMMARY OF INVENTION




An object of the present invention is to provide a cigarette containing cut filler or other form of shredded tobacco, which cigarette is adapted to cooperate with an electrical lighter and render satisfying levels of delivery and taste.




Another object of the present invention is to provide a cigarette for an electrical smoking system which includes cut filler, yet provides improved consistency in delivery from puff to puff.




Another object of the present invention is to provide a cigarette adapted for use in electrical smoking systems, which cigarette is resistive to breakage during the withdrawal of the cigarette from the lighter thereof.




It is still a further object of this invention to provide a novel cigarette that is operative with an electrical lighter and conducive to cost-effective methods of manufacture, even at production speeds.




These and other objects are achieved with the present invention which provides an electrical smoking system comprising a cigarette and an electric lighter, wherein the cigarette comprises a tubular tobacco mat partially filled with material tobacco so as to define a filled tobacco rod portion and an unfilled tobacco rod portion. The filled tobacco rod portion is situated adjacent a free end of said cigarette. The lighter comprises an electrical heater element and a system for electrically actuating said heater element, with the lighter being arranged to at least partially receive said cigarette. The cigarette and the lighter are mutually arranged so that when the cigarette is received in the lighter, the electrical heater element of the lighter at least partially superposes at least a portion of the filled tobacco rod portion. The cigarette and the lighter are also mutually arranged so that when the cigarette is received in the lighter, the free end of the cigarette is occluded. Furthermore, the cigarette includes a zone of perforations at a location along the filled tobacco rod portion, with the cigarette being free of perforations along the unfilled tobacco rod portion.




By such arrangements and others, the delivery (total particulate matter (“TPM”) per FTC testing methodology) of the electrical smoking system may be increased without producing a hot, harsh-tasting smoke. Importantly, the enhanced delivery is achieved without overdriving the heater element of the lighter. The elevated delivery is achieved without additional load upon the batteries of the lighter and without driving the heater element to excessive peak temperatures.




A further aspect is provision of cooperative features within the lighter and the cigarette such that a large majority of the resistance to draw of the smoking system originates along the side walls of cigarette, with a lesser portion originating from flow passages within the lighter.




A further aspect of the present invention is provision of an air-flow deflector along an interior portion of the lighter to favorably direct air toward the cigarette.




In addition to the above, the invention provides an apparatus for perforating a tobacco rod prior to assembly of the tobacco rod to a filter rod via tipping paper, comprising a drum link-up assembly adapted to transfer a tobacco rod from a combining apparatus to a tipping apparatus wherein the tobacco rod is attached to a filter rod by tipping paper; and a laser perforating apparatus adapted to bum one or more holes in an outer surface of the tobacco rod while the tobacco rod is in the drum link-up assembly.




According to one embodiment of the invention, the laser perforating apparatus includes a lens arrangement which bums at least one circumferentially extending row of perforations around the tobacco rod. According to another embodiment, the drum link-up assembly includes a drum having flutes on an outer surface thereof, the laser perforating apparatus being adapted to rotate the tobacco rod about its axis while pulsing a laser to burn the at least one row of perforations into the tobacco rod as the tobacco rod is rolled from one flute to an adjacent flute. If desired, the laser perforating apparatus can include a beam splitter which separates a beam from a pulsed laser into at least two beams which bum at least two rows of elongated holes into the tobacco rod to form a laser perforated tobacco rod. Preferably, the drum link-up assembly comprises at least one rotating drum having flutes sized to carry 2-up tobacco rods.




According to a preferred embodiment, the drum link-up assembly includes a series of drums which transfer 2-up tobacco rods to the tipping machine, the drums including a catch drum, a transfer drum, a swash plate drum, a laser drum, a cutting drum, and a separating drum, the catch drum receiving 2-up tobacco rods from a delivery device of a combining apparatus and delivering the 2-up tobacco rods to the transfer drum, the transfer drum delivering the 2-up tobacco rods to the swash plate drum, the swash plate drum aligning the 2-up tobacco rods and delivering the aligned 2-up tobacco rods to the laser drum, the laser drum orienting the 2-up tobacco rods such that the laser perforating apparatus bums at least two longitudinally spaced apart rows of perforations on each of the 2-up tobacco rods, the laser drum delivering the 2-up tobacco rods to the cutting drum, the cutting drum cutting the 2-up tobacco rods into a pair of tobacco rods of unit length and delivering the pair of tobacco rods to the separating drum at which the pair of tobacco rods are spaced longitudinally apart, the separating drum delivering the tobacco rods to an assembly drum of a tipping apparatus at which the pair of tobacco rods are combined with a 2-up filter rod by placing the 2-up filter rod between the pair of spaced apart tobacco rods.




The apparatus can further comprise a combining machine which includes means for wrapping a tobacco plug and a free-flow filter plug within a tobacco matt and an outer paper wrapper to form a continuous tobacco rod, the combining machine including a cutting apparatus which cuts the continuous tobacco rod into 2-up tobacco rod segments, the laser perforating apparatus being adapted to burn perforating holes at locations on the 2-up tobacco rods such that the perforating holes pass through the outer paper wrapper and the tobacco matt and into the tobacco plugs of the 2-up tobacco rod segments. Further, the apparatus can include a tipping apparatus which includes means for attaching the perforated tobacco rods to filter rods by locating a 2-up filter rod in a space between a pair of the perforated tobacco rods, wrapping tipping paper around the 2-up filter rod such that the tipping paper overlaps portions of the perforated tobacco rods, gluing ends of the tipping paper together, and cutting the 2-up filter rods to produce a pair of cigarettes. If desired, the tipping apparatus can include a laser perforating station at which the cigarettes are provided with additional perforation holes, the laser perforating station including a lens arrangement which provides at least one circumferentially extending row of the additional perforations at a location along the tobacco rod.




The invention also provides a method of perforating a tobacco rod prior to assembly of the tobacco rod to a filter rod via tipping paper, comprising supplying a tobacco rod to a drum link-up assembly wherein the tobacco rod is moved from a combining apparatus to a tipping apparatus wherein the tobacco rod is attached to a filter rod by tipping paper, and forming a perforated tobacco rod by actuating a laser perforating apparatus so as to burn one or more perforating holes in an outer surface of the tobacco rod while the tobacco rod is in the drum link-up assembly.




Another object of the present invention is to establish a method of manufacturing with high speed production machinery a cigarette of the type operable with an electric lighter and containing cut filler.




It is another object of the present invention to provide a cigarette suited for consumption with a lighter of an electrical smoking system and a method of manufacturing same, wherein the cigarette is not subjected to forces which would tend to collapse or break the cigarette during its manufacture.




It is still a further object of this invention to provide a novel cigarette that is operative with an electrical lighter and a cost-effective method of manufacturing the cigarette.




These objects and other advantages are provided by the present invention which provides a cigarette operable with an electrically operated lighter, which lighter includes a plurality of electrical heaters, with each of the heaters being adapted to, either singularly or in concert, to generate tobacco smoke by applying heat to the cigarette along portions of the cigarette adjacent the heaters as a result of activation of the heater or heaters.




In accordance with one aspect of the present invention, the cigarette comprises a tubular tobacco web, wherein a first portion of the tubular tobacco web is filled with a column of tobacco, preferably in the form of cut filler, and a second portion of the tubular tobacco web is left unfilled or hollow so as to define a void in the tobacco column.




More particularly, the aforementioned cigarette preferably comprises a tobacco rod formed from a tubular tobacco web and a plug of tobacco located within the tubular tobacco web. The tobacco rod is adapted to be slidingly received by an electrical heater fixture such that the heater elements locate alongside the tobacco rod at a location between the free end and an opposite end of the tobacco rod. Preferably the plug (or column) of tobacco extends from the free end of the tobacco rod to a location that is spaced from the opposite end of the tobacco rod so as to define a void (or hollow portion) adjacent the opposite end.




Still another aspect of the present invention is to provide a filler containing cigarette that is operative with an electrical lighter, which cigarette includes a tobacco rod having a free-flow filter and a filler-free rod portion adjacent the free flow filter so as to promote consistent aerosol production.




A preferred embodiment of the present invention provides a method of manufacturing such cigarettes, wherein the method comprises the steps of establishing a succession of 2-up hollow plugs in alternating, spaced apart relation to 2-up tobacco plugs and wrapping the succession of plugs in a tobacco web and overwrap so as to produce a continuous rod; severing the resultant continuous rod to establish associated pairs of singular tobacco rod plugs; separating the members of each associated pair of singular tobacco rod plugs so as to establish a space therebetween; placing a 2-up filter tipping plug in the space between each a pair of separated, singular tobacco rod plugs; bringing the 2-up filter tipping plug and said singular tobacco rod plugs together into an abutting relation; and subsequently wrapping tipping paper about the placed 2-up filter tipping plug together with adjacent portions of the abutting singular tobacco rod plugs to form a 2-up cigarette rod; and severing the 2-up cigarette into individual cigarettes.











BRIEF DESCRIPTION OF THE DRAWINGS




The features and advantages of the present invention are well understood by reading the following detailed description in conjunction with the drawings in which like numerals indicate similar elements and in which:





FIG. 1

is a perspective view of a smoking system in accordance with a preferred embodiment of the present invention with a cigarette of the system inserted into the electrically operated lighter;





FIG. 2

is a perspective view of the smoking system of

FIG. 1

, but with the cigarette withdrawn from the lighter upon conclusion of a smoking;





FIG. 3A

is a partial perspective detail view of portions of the heater fixture of

FIG. 1

, including wavy hairpin heater elements and portions of a preferred air admission system;





FIG. 3B

is a sectional side view of a preferred heater fixture which includes the wavy hairpin heater elements of

FIG. 3A

;





FIG. 3C

is a side view of the cigarette shown in

FIG. 4

inserted into the heater fixture of

FIG. 6

, with the latter being shown in cross-section;





FIG. 4

is a detail perspective view of a preferred embodiment of the cigarette shown in

FIG. 1

, with certain components of the cigarette being partially unraveled;





FIG. 5

is a schematic, block-diagram of a preferred control circuit for the lighter shown in

FIGS. 1 and 2

;





FIG. 6

is a side cross sectional view of the cigarette shown in

FIG. 4

wherein a free end of the cigarette is in contact with a stop piece in the lighter;





FIG. 7

is a representation of steps and apparatus in a preferred process of manufacturing tobacco rod portions of the cigarette shown in

FIG. 4

in accordance with a preferred method of manufacturing such cigarettes;





FIGS. 8A-8E

are successive cross-sectional views at lines A—A to E—E, respectively at the garniture in

FIG. 7

, as components of the cigarette shown in

FIG. 4

progress through the garniture;





FIG. 9

is a diagram of a tipping apparatus which is adapted to attach filter tipping to the tobacco rod portions produced in accordance with the process in

FIG. 7

;





FIGS. 10A and 10B

are diagrams showing the relative movement and placement of cigarette pieces during execution of the tipping operation of the preferred method of manufacturing cigarettes of the type shown in

FIG. 4

;





FIG. 11

shows a perspective side view of a laser perforating apparatus which can be used to burn perforation holes in tobacco rods in accordance with the invention;





FIG. 12

is a perspective view of the apparatus shown in

FIG. 11

but from an opposite side thereof;





FIG. 13

is a cross sectional view of a portion of the apparatus shown in

FIG. 11

;





FIG. 14

is a cross sectional view of a beam splitting arrangement which can be used in the apparatus shown in

FIG. 1

; and





FIG. 15

is a schematic diagram showing a combining apparatus directly linked to a tipping apparatus by a transfer apparatus in accordance with the invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring to

FIGS. 1 and 2

, a preferred embodiment of the present invention provides a smoking system


21


which preferably includes a partially-filled, filter cigarette


23


and a reusable lighter


25


. The cigarette


23


is adapted to be inserted into and removed from a cigarette receiver


27


which is open at a front end portion


29


of the lighter


25


. Once the cigarette


23


is inserted, the smoking system


21


is used in much the same fashion as a more traditional cigarette, but without lighting or smoldering of the cigarette


23


. The cigarette


23


is discarded after one or more puff cycles. Preferably, each cigarette


23


provides a total of eight puffs (puff cycles) or more per smoke; however it is a matter of design expedient to adjust to a lesser or greater total number of available puffs. In the preferred embodiment, the cigarette


23


includes at least one peripheral ring of perforations


12


located adjacent the free end


15


of the cigarette


23


and optionally a second ring or rings of perforations


14


and optionally a plurality of holes


16


underneath the outer wrapper of the cigarette


23


.




Further particulars of the smoking system is described also in the commonly assigned, U.S. Pat. Nos. 5,388,594; 5,505,214; 5,591,368 and 5,499,636, all which are hereby incorporated by reference in their entireties.




The lighter


25


includes a housing


31


having front and rear housing portions


33


and


35


. One or more batteries


35




a


are removably located within the rear housing portion


35


and supply energy to a heater fixture


39


which includes a plurality of electrically resistive, heating elements


37


(shown in FIGS.


3


A-C). The heating elements


37


are arranged within the front housing portion


33


to slidingly receive the cigarette


23


along an intermediate portion of the cigarette receiver


27


. A stop


183


located at the base


300


of the heater fixture


39


defines a terminus of the cigarette receiver


27


.




A control circuit


41


in the front housing portion


33


selectively establishes electrical communication between the batteries


35




a


and one or more the heater elements


37


during execution of each puff cycle. The preferred embodiment of the present invention includes details concerning an air management system for effecting the admission and routing of air within the lighter, including aspects which are discussed in greater detail beginning with reference to FIG.


3


C.




Still referring to

FIGS. 1 and 2

, preferably the rear portion


35


of the lighter housing


31


is adapted to be readily opened and closed, such as with screws or snap-fit components, so as to facilitate replacement of the batteries. If desired, an electrical socket or contacts may be provided for recharging the batteries in a charger supplied with house current or the like. Preferably, the front housing portion


33


is removably joined to the rear housing portion


35


, such as with a dovetail joint or a socket fit.




The batteries


35




a


are sized to provide sufficient power for the heaters


37


to function as intended and preferably comprise a replaceable and rechargeable type. Alternate sources of power are suitable, such as capacitors. In the preferred embodiment, the power source comprises four nickel-cadmium battery cells connected in series with a total, non-loaded voltage in the range of approximately 4.8 to 5.6 volts. The characteristics of the power source are, however, selected in view of the characteristics of other components in the smoking system


21


, particularly the characteristics of the heating elements


37


. Commonly assigned U.S. Pat. No. 5,144,962, hereby incorporated by reference, describes several types of power sources useful in connection with the smoking system of the present invention, such as rechargeable battery sources and power arrangements which comprise a battery and a capacitor which is recharged by the battery.




Referring specifically to

FIG. 2

, preferably, the circuitry


41


is activated by a puff-actuated sensor


45


that is sensitive to either changes in pressure or changes in rate of air flow that occur upon initiation of a draw on the cigarette


23


by a smoker. The puff-actuated sensor


45


is preferably located within the front housing portion


33


of the lighter


25


and is communicated with a space inside the heater fixture


39


adjacent the cigarette


23


via a port


45




a


extending through a side wall portion


182


of the heater fixture


39


. A puff-actuated sensor


45


suitable for use in the smoking system


21


is described in commonly assigned U.S. Pat. No. 5,060,671 and U.S. Pat. No. 5,388,594, the disclosures of which are incorporated herein by reference. The puff sensor


45


preferably comprises Fujikura Ltd. Model FSS-02 PG. Another suitable sensor is a Model 163PCO1D35 silicon sensor, manufactured by the MicroSwitch division of Honeywell, Inc., Freeport, Ill. Flow sensing devices, such as those using hot-wire anemometry principles, have also been successfully demonstrated to be useful for actuating an appropriate one of the heater elements


37


upon detection of a change in air flow. Once actuated by the sensor


45


, the control circuitry


41


directs electric current to an appropriate one of the heater elements


37


.




An indicator


51


is provided at a location along the exterior of the lighter


25


, preferably on the front housing portion


33


, to indicate the number of puffs remaining in a smoke of a cigarette


23


. The indicator


51


preferably includes a seven-segment liquid crystal display. In the preferred embodiment, the indicator


51


displays a segmented image which correlates with the digit “8” when a cigarette detector


57


detects the presence of a cigarette in the heater fixture


39


. The detector


57


preferably comprises an inductive coil


1102


adjacent the cigarette receiver


27


of the heater fixture


39


and electric leads


1104


that communicate the coil


1102


with an oscillator circuit within the control circuitry


41


. The cigarette


23


internally bears a foil ring or the like which can affect inductance of the coil winding


1102


such that whenever a cigarette


23


is inserted into the receiver


27


, the detector


57


generates a signal to the circuitry


41


indicative of the cigarette being present. The control circuitry


41


in turn provides a signal to the indicator


51


. The display of the digit “8” on the indicator


51


reflects that the eight puffs provided on each cigarette


23


are available, i.e., no puff cycle has been undertaken and none of the heater elements


37


have been activated to heat the cigarette


23


. After the cigarette


23


is fully smoked, the indicator displays the digit “0”. When the cigarette


23


is removed from the lighter


25


, the cigarette detector


57


no longer detects a presence of a cigarette


23


and the indicator


51


is turned off.




The operation and details of the inductive cigarette detector


57


is provided in commonly assigned U.S. Pat. No. 5,902,501, which is incorporated herein by reference in its entirety. Other detectors may be employed instead of the above-described one for the detector


57


, such as a Type OPR5005 Light Sensor, manufactured by OPTEX Technology, Inc., 1215 West Crosby Road, Carrollton, Tex. 75006.




In the alternative to displaying the remainder of the puff count, the detector display may instead be arranged to indicate whether the system is active or inactive (“on” or “off”).




As one of several possible alternatives to using the above-noted cigarette detector


57


, 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 into the lighter


25


, e.g., to cause the indicator


51


to display the digit “8”, etc. Power sources, circuitry, puff-actuated sensors, and indicators useful with the smoking system


21


of the present invention are described in commonly assigned, U.S. Pat. Nos. 5,060,671; 5,388,594 and 5,591,368, all which are incorporated herein by reference.




Referring now to

FIGS. 3A and 3B

, the front housing portion


33


of the lighter


25


encloses a substantially cylindrical heater fixture


39


whose heater elements


37


slidingly receive the cigarette


23


. The heater fixture


39


is adapted to support an inserted cigarette


23


in a fixed relation to the heater elements


37


such that the heater elements


37


are positioned alongside the cigarette


23


at approximately the same location along each newly inserted cigarette


23


. In the preferred embodiment, the heater fixture


39


includes eight mutually parallel heater elements


37


which are disposed concentrically about the axis of symmetry of the cigarette receiver


27


. The locations where each heater element


37


bears against (or is in thermal communication with) a fully inserted cigarette


23


is referred to herein as the heater footprint or char zone


42


. In the preferred embodiment, the char zone may extend approximately 14 mm in length, beginning approximately 9 mm from the free-end


15


of the cigarette


23


. Of course, these relations may be varied amongst different lighter and cigarette designs. In another model for example, the char zone


42


extends from 12 mm to 23 mm from the free-end of the cigarette


23


.




Referring also to

FIG. 3C

, to assure consistent placement of the heating elements


37


relative to each cigarette


23


from cigarette to cigarette, the heater fixture


39


is provided with a base portion


300


having a cupped stop-piece


183


against which the free end


15


of the cigarette


23


is urged during its insertion into the cigarette receiver


27


of the lighter


25


. The cupped shape of the stop-piece


183


is configured to close-off (occlude) the free end


15


of the cigarette


23


upon full insertion of the cigarette


23


so that air cannot be drawn through the free end


15


, but instead only from along the side walls of the cigarette


23


.




Still referring to

FIGS. 3A and 3B

, most preferably the heater elements


37


are of a design referred to herein as a wavy hairpin heater element


37


, wherein each heater element


37


includes at least first and second serpentine, elongate members


53




a


and


53




b


which are adjoined at an end portion (tip)


54


. The tips


54


are adjacent the opening


55


of the cigarette receiver


27


. The opposite ends


56




a


and


56




b


of each heater element


37


are electrically connected to the opposite poles of the power source


35




a


as selectively established by the controller


41


. More specifically, an electrical pathway through each heater fixture


37


is established, respectively, through a terminal pin


104


, a connection


121


between the pin


104


and a free end portion


56




a


of one of the serpentine members


53




a


, through at least a portion of the tip


54


to the other serpentine member


53




b


and its end portion


56




b


. Preferably, an integrally formed, common connection ring


110


provides a common electrical connection amongst all the end portions


56




b


of the elongate member


53




b


. In the preferred embodiment, the ring


110


is connected to the positive terminal of the power source


35




a


(or common) through a connection


123


between the ring


110


and a pin


105


. Further details of the construction and establishment of electrical connections in the heater fixture


39


are illustrated and described in the commonly assigned U.S. Pat. Nos. 5,060,671; 5,388,594 and 5,591,368, all which are incorporated herein by reference.




The heater portions


53




a


,


53




b


and


54


establish what is here referred to as a heater blade


120


.




Other preferred designs of the heater fixture


39


include heater elements in the form of a straight hairpin heater elements


37


, which are set forth in the commonly assigned U.S. Pat. No. 5,591,368 and “singular serpentine” heater elements each which are set forth in commonly assigned U.S. Pat. No. 5,388,594, said patents being incorporated herein by reference in their entireties.




Additional heater fixtures


37


that are operable as part of the lighter


25


include those disclosed in commonly assigned, U.S. Pat. No. 5,665,262; and commonly assigned, U.S. Pat. No. 5,498,855, all which are incorporated herein by reference in their entireties.




Preferably, the heaters


37


are individually energized by the power source


35




a


under the control of the circuitry


41


to heat the cigarette


23


preferably eight times at spaced locations about the periphery of the cigarette


23


. The heating renders eight puffs from the cigarette


23


, as is commonly achieved with the smoking of a more traditional cigarette. It may be preferred to activate more than one heater simultaneously for one or more or all of the puffs.




Referring now to

FIG. 4

, the cigarette


23


is preferably constructed in accordance with the preferred embodiment set forth in commonly assigned, U.S. Pat. No. 5,499,636, herein incorporated by reference in its entirety.




Referring particularly to

FIGS. 3A

,


3


B, and


3


C, preferably the puff sensor


45


is communicated to the interior of the heater fixture


39


through a port


45




a


. Preferably, the port


45




a


is located adjacent the base portion


300


of the heater fixture


39


. Such location minimizes the risk that the port


45




a


and adjacent passageways leading thereto through the body of the heater fixture


39


would become clogged by the debris or smoke condensates.




The heater fixture


39


includes an air inlet port


1200


, which communicates with a manifold


1202


that is at least partially defined by a perforated annulus


1204


and the body of the receiver


27


. The annulus


1204


includes preferably four holes


1206


of approximately 0.029 inch diameter for effecting a minimal pressure drop as air is drawn into the lighter through the air inlet port


1200


and the manifold


1202


. The size and number of the holes


1206


may be varied, but such are configured to provide sufficient pressure drop that upon drawing action upon an inserted cigarette


23


, a pressure drop is induced upon the air entering the lighter such that the puff sensor


45


is operative to recognize initiation of a puff. In the preferred embodiment, the holes


1206


of the annulus


1204


induce an RTD of approximately 25 mm water plus or minus 5 mm. The range of pressure drop induced at the annulus


1204


should be selected such that it is within the range of pressure drop detectable by the pressure sensor


45


, but minimized to that need so that the remainder of desired RTD (Resistance To Draw) is effected predominantly by the cigarette


23


. In the preferred embodiment, a grand total RTD of 4 to 5 inches water (100 to 130 mm water) is desired and approximately 25 mm of that is produced at the annulus


1204


. Accordingly, the RTD of the cigarette


23


is preferably in the range of approximately 75 to 105 mm water RTD, when inserted in lighter


25


and the induced pressure drop of the lighter


25


is approximately 25 mm water. Adjustment of cigarette RTD in accordance with the present invention includes provision of and adjustment of the number and extent of perforations


12


(and optionally


14


) in the filled portion


88


of the cigarette


23


.




Advantageously, the holes


1206


of the annulus


1204


, being located adjacent the receiver


27


, is positioned away from sources of debris and condensates which might otherwise tend to clog the holes


1206


.




Air that has been drawn into the lighter upon initiation of a puff enters alongside the cigarette with a substantial longitudinal (axial) velocity component toward the base portion


300


of the heater fixture


300


. It has been discovered that a flow deflector or annular air-swoop


1210


adjacent the base portion


300


enhanced smoke output (delivery) of the system


21


by directing at least a portion of the entering airflow back toward the inserted cigarette


23


. Not wishing to be bound by theory, it is believed that the air-swoop


1210


tends to direct airflow toward regions of the cigarette


23


bearing perforations


12


. Preferably, the annular air-swoop


1210


is located relative to a fully inserted cigarette


23


such that the air-swoop


1210


circumscribes the general location along the cigarette


23


of the perforations


12


.




It has discovered that the functioning of the air-swoop


1210


is improved if it is constructed from metal, or alternatively, all body portions of the heater fixture


39


are constructed from a metal such as a stainless steel, or at least those portions of the heater fixture


39


that are disposed adjacent an inserted cigarette


23


. Such provision can provide an increase of delivery of 1 mg TPM (FTC).




The cigarette


23


comprises a tobacco rod


60


and a filter tipping


62


, which are joined together with tipping paper


64


.




The tobacco rod


60


of the cigarette


23


preferably includes a tobacco web or “mat”


66


which has been folded into a tubular (cylindrical) form about a free-flow filter


74


at one of its ends and a tobacco plug


80


at the other. In the alternative, a plug of cellulose acetate might be used in place of the tobacco plug


80


. The longitudinal (axial) extent of the tobacco plug


80


defines a tobacco filled portion


88


of the partially-filled cigarette


23


.




An overwrap


71


is intimately enwrapped about the tobacco web


66


and is held together along a longitudinal seam as is common in construction of more traditional cigarettes. The overwrap


71


retains the tobacco web


66


in a wrapped condition about a free-flow filter


74


and a tobacco plug


80


.




The tobacco web


66


itself preferably comprises a base web


68


and a layer of tobacco material


70


located along the inside surface of the base web


68


. At the tipped end of the tobacco rod


60


, the tobacco web


66


together with the overwrap


71


are wrapped about the tubular free-flow filter plug


74


. Preferably, the tobacco plug


80


is constructed separately from the tobacco web


66


and comprises a relatively short column of cut filler tobacco that preferably has been wrapped within and retained by a plug wrap


84


.




As a general matter, the length of the tobacco plug


80


is preferably set relative to the total length of the tobacco rod


60


such that a void


90


is established along the tobacco rod


60


between the free-flow filter


74


and the tobacco plug


80


. The void


90


corresponds to an unfilled portion of the tobacco rod


60


and is in immediate fluid communication with the tipping


62


through the free flow filter


74


of the tobacco rod


60


.




The tipping


62


preferably comprises a free-flow filter


92


located adjacent the tobacco rod


60


and a mouthpiece filter plug


94


at the distal end of the tipping


62


from the tobacco rod


60


. Preferably, the free-flow filter


92


is tubular and transmits air with very little pressure drop. Other low efficiency filters of standard configuration could be used instead, however. The inside diameter for the free flow filter


92


is preferably at or between 2 to 6 mm and is preferably greater than that of the free flow filter


74


of the tobacco rod


60


.




The mouthpiece filter plug


94


closes off the free end of the tipping


62


for purposes of appearance and, if desired, to effect some filtration, although it is preferred that the mouthpiece filter plug


94


comprise a low efficiency filter of preferably about 15 to 25 percent efficiency.




Still referring to

FIG. 4

, preferably, the partially-filled cigarette


23


includes at least one row of perforations


12


at a location adjacent the free end


15


of the tobacco rod portion of the cigarette


23


. Preferably, the row of perforations


12


are twelve holes in count and may be formed as slits


17


(perf-holes) at a 400 microsecond pulse width setting of a Hauni Model 500-1 on-line laser perforator system. Each perf-hole


17


of the row of perforations


12


preferably extends through the outer wrapper


71


, through the tobacco mat


66


and the plug wrap


84


.




Referring now also

FIG. 2

, preferably, the row of perforations


12


is located at or adjacent to end portion


42




a


of the char zone


42


. Such placement is believed to promote entrance of heated air into the tobacco plug


80


and create other additional favorable effects upon pyrolysis during a puff cycle such that delivery (TPM-FTC) is enhanced.




To further improve delivery, additional row or rows of perforations


14


comprising perf holes


17


as previously described may be provided at a location along the filled portion


88


of the tobacco rod


60


preferably, at a location superposed, or at least partially superposed, by the heater char zone or footprint


42


and/or alternatively, adjacent the free end


15


of the cigarette


23


. In the latter alternate embodiment, the second row of perforations


14


is established at approximately 4 mm from the free end


15


of the cigarette


23


. Either or both of the perforation rows


12


or


14


may comprise a single row or a dual row of perf-holes


17


.




The number and extent of perf-holes


17


are resolved in accordance with two countervailing considerations. The addition of rows of perforation


12


,


14


as described above contributes to enhanced delivery of the cigarette


23


. However, each additional row of perforations


12


,


14


reduces RTD along the side walls of the cigarettes


23


. Preferably, the grand total RTD of the electrical smoking system


21


should provide the smoker a resistance to draw approximately the same as that experience with traditional cigarettes of approximately 4 to 5 inches water (approximately 100-130 mm water) or thereabouts, 80-130 mm water.




It has been found that at a total energy input of 23.8 Joules to a heater element


37


, a cigarette


23


bearing a dual row of perforations


12


at a location 12 mm from the free end


15


of the cigarette (dual rows of 12 holes each) can produce deliveries substantially greater than 3 milligrams TPM (FTC). Further deliveries may be obtained by addition of a second row or rows of perforations


14


.




However, each additional row of perf-holes


17


lowers RTD, which preferably is to remain at or above 100 mm water for the whole system


21


. Should one find that for a given cigarette


23


, additional delivery is desired yet the RTD level is nearing its lower limit, additional delivery can be obtained by provision of a plurality of circumferentially spaced-apart holes


16


placed in the mat


66


itself. Preferably, the mat holes


16


are each approximately one mm in diameter and preferably


6


in number so that the requisite tensile strength of the mat material


66


is maintained and may withstand machine manufacturing. Preferably, these holes are formed by an opposing punch-and-die roller assembly


240


as shown in

FIG. 7

which is located along the feed-path of the mat in the cigarette making operation, as is described in U.S. Pat. No. 5,666,976, which patent is hereby incorporated by reference in its entirety.




For example, in the preferred embodiment, the mat holes


16


are preferably produced utilizing opposing rollers bearing hole-punching elements. Other devices may be employed instead, such as a disk or endless belt arrangement located along the feed path of the mat, with the disk or endless belt including multiple hole-punching dies which are brought to approximate feed speed of the mat by the movement of the disk or endless belt.




Preferably, the holes


16


in the mat


66


are covered by the outer wrapper


71


. Preferably, any row of perforations


12


,


14


is displaced away from the location of the row of mat holes


16


so that they do not overlap. In a preferred embodiment, the mat holes


16


are located approximately 7 mm from the free-end


15


of the cigarette


23


, and a dual row of perforations


12


is established approximately 12 mm from the end


15


of the cigarette


23


. So arranged, the cigarette achieves a 6 mg TPM (FTC) or more. Advantageously, the mat holes


16


can contribute an additional delivery to the cigarette


23


without the same extent of reduction in RTD as is experienced with each addition of row of perf-holes


17


. Accordingly, one may utilize the rows of perforations


12


,


14


to approximate desired delivery levels for the cigarette


23


, with the mat holes


16


being used to adjust or increase delivery with a lesser effect on RTD.




More traditional cigarettes exhibit a resistance to draw (RTD) of approximately 80 mm to 130 mm water. The lighter of the electrical smoking system according to the present invention when tested without a cigarette exhibits an RTD of approximately 20-30 mm water. The cigarettes according to the present invention having the laser perforations and mat holes as taught herein exhibit an RTD of approximately 20-30 mm water when drawn upon by themselves (outside of the lighter of the electrical smoking system), but when inserted, the electrical smoking system (the lighter and the fully inserted cigarette) generate an RTD of approximately 50-75 mm water. Table 1 sets forth results of RTD measurements for cigarettes without perforations or mat holes, cigarettes with mat holes only and cigarettes with mat holes and a double row of laser perforations. The cigarettes had a circumference of 24 to 25 mm, the mat holes consisted of a single row of 6 mat holes 7 mm from the end of the cigarettes and the double row of perforations consisted of 12 holes in each row at a location about 12 mm from the end of the cigarette with the rows about 1 mm apart.

















TABLE 1












Circumference




RTD-OE




RTD-BE







Run




(mm)




(mm)




(mm)





























1




24.58




32




875







2




24.53




35




551







3




24.57




30




57













- circumference and RTD values are average of results obtained for 25 cigarettes tested during each run











OE RTD of cigarettes tested in smoking machine with tobacco end of cigarettes open to atmosphere











BE RTD of cigarettes tested in smoking machine with tobacco end of cigarettes blocked by cup fitted over cigarette end













In order to compare various aspects of cigarettes having various combinations of perf-holes


17


and mat holes


16


to cigarettes having no perforations or holes, test cigarettes having circumferences of 24 to 25 mm were constructed having the features set forth in Table 2.




The control cigarette had no perforations nor mat holes and test cigarettes


1


-


7


included laser perforations located 12 mm from the tobacco end of the cigarette and/or mat holes located 7 mm from the tobacco end of the cigarette.




The test cigarettes with laser perforations included either a single row of evenly spaced laser cut slits extending circumferentially around the cigarette or a double row of such laser perforations wherein the rows are located approximately 1 mm apart.




The test cigarettes with mat holes included a single row of six evenly spaced mat holes having diameters of 1 mm circumferentially spaced about the cigarette. As shown in the test results, the sample having a double row of 12 laser holes and the six 1 mm diameter mat holes provided tobacco smoke having the highest TPM. In the tests, the electrical smoking system was mounted in a conventional cigarette smoking machine that measures that portion of the smoke which is collected on a pad, its tar, nicotine and water. During the tests, the cigarette smoking machine was operated under FTC smoking conditions wherein a 2 second puff is taken every 60 seconds for a total of 8 puffs.
















TABLE 2











Tar,




Nicotine,




Water,






Description




TPM, mg/cig.




mg/cig.




mg/cig




mg/cig











Control




5.24




2.18




0.15




2.91
















1




single row of 6




5.67




2.36




0.18




3.12







laser perforations






2




single row of 12




5.25




2.15




0.17




2.92







laser perforations






3




double row of 6




5.28




2.08




0.15




2.73







laser perforations







per row






4




double row of 12




5.57




2.06




0.17




3.34







laser perforations







per row






5




single row of 6




5.41




2.25




0.18




2.97







laser perforations







and 6 mat holes






6




double row of 12




6.44




2.39




0.19




3.86







laser perforations







and 6 mat holes






7




6 mat holes only




5.56




2.07




0.16




3.33














Referring now to

FIGS. 2 and 5

, the electrical control circuitry


41


of the lighter


25


includes a logic circuit


195


, which preferably comprises a micro-controller or an application specific, integrated circuit (or “ASIC”). The control circuitry also includes the cigarette sensor


57


for detecting the insertion of a cigarette


23


in the cigarette receiver


27


of the lighter


25


, the puff sensor


45


for detecting a draw upon the inserted cigarette


23


, the LCD indicator


51


for indicating the number of puffs remaining on a cigarette, the power source


35




a


and a timing network


197


.




The logic circuit


195


may comprise any conventional circuit capable of implementing the functions discussed herein. A field-programmable gate array (e.g., a type ACTEL A1280A FPGA PQFP 160, available from Actel Corporation, Sunnyvale, Calif.) or a micro controller can be programmed to perform the digital logic functions with analog functions performed by other components. An ASIC or micro-controller can perform both the analog and digital functions in one component. Features of control circuitry and logic circuitry similar to the control circuit


41


and logic circuit


195


of the present invention are disclosed, for example, in commonly assigned, U.S. Pat. Nos. 5,388,594; 5,505,214; 5,591,368; and 5,499,636, all which are hereby incorporated by reference in their entireties. Further details are also provided in the copending, commonly assigned U.S. Pat. No. 6,040,560, hereby incorporated by reference in its entirety.




In the preferred embodiment, eight individual heater elements


37


are connected to a positive terminal of the power source


35




a


and to ground through corresponding field effect transistor (FET) heater switches


201


-


208


. Individual (or selected) ones of the heater switches


201


-


208


will turn on under control of the logic circuit


195


through terminals


211


-


218


, respectively, during execution of a power cycle by the logic circuit


195


. The logic circuit


195


provides signals for activating and deactivating particular ones of the heater switches


201


-


208


to activate and deactivate the corresponding heater element


37


of the heater fixture


39


.




The logic circuit


195


cooperates with the timing circuit


197


to precisely execute the activation and deactivation of each heater element


37


in accordance with a predetermined total cycle period (“T


total


”) and to precisely divide each total cycle period into a predetermined number of phases, with each phase having its own predetermined period of time (“t


phase


”). In the preferred embodiment, the total cycle period T


total


has been selected to be 1.6 seconds (so as to be less than the two-second duration normally associated with a smoker's draw upon a cigarette, plus provision for margin) and the total cycle period T


total


is divided preferably into two phases, a first phase having a predetermined time period (“t


phase 1


”) of 1.0 seconds and a second phase having a predetermined time period (“t


phase 2


”) of 0.6 seconds. The total cycle period T


total


, the total number of phases and the respective phase periods are parameters, among others, that are resolved in accordance with the teachings which follow for establishing within the control circuit


41


, a capacity to execute a power cycle that precisely duplicates a preferred thermal interaction (“thermal profile” or “thermo-histogram”) between the respective heater element


37


and adjacent portions of the cigarette


23


. Additionally, once the preferred thermo-histogram is established, certain parameters (preferably, duty cycles within each phase) are adjusted dynamically by the control circuit


41


so as to precisely duplicate the predetermined thermo-histogram with every power cycle throughout the range of voltages v


in


encompassed by the aforementioned battery discharge cycle.




The puff-actuated sensor


45


supplies a signal to the logic circuit


195


that is indicative of smoker activation (i.e., a continuous drop in pressure or air flow over a sufficiently sustained period of time). The logic circuit


195


includes a debouncing routine for distinguishing between minor air pressure variations and more sustained draws on the cigarette to avoid inadvertent activation of heater elements in response to errant signal from the puff-actuated sensor


45


. The puff-actuated sensor


45


may include a piezoresistive pressure sensor or an optical flap sensor that is used to drive an operational amplifier, the output of which is in turn used to supply a logic signal to the logic circuit


195


. Puff-actuated sensors suitable for use in connection with the smoking system include a Model 163PC01D35 silicon sensor, manufactured by the MicroSwitch division of Honeywell, Inc., Freeport, Ill., or a type NPH-5-02.5G NOVA sensor, available from Lucas-Nova, Fremont, Calif., or a type SLP004D sensor, available from SenSym Incorporated, Sunnyvale, Calif.




The cigarette sensor


57


is located at the cigarette receiver


27


and supplies a signal to the logic circuit


195


that is indicative of insertion of a cigarette


23


in the lighter


25


. Optionally a second sensor may be located adjacent the stop


183


so as to determine whether the cigarette has been fully inserted into the receiver


27


.




In order to conserve energy, it is preferred that the puff-actuated sensor


45


and the cigarette sensor


57


be cycled on and off at low duty cycles (e.g., from about a 2 to 10% duty cycle). For example, it is preferred that the puff actuated sensor


45


be turned on for a 1 millisecond duration every 10 milliseconds. If, for example, the puff actuated sensor


45


detects pressure drop or air flow indicative of a draw on a cigarette during four consecutive pulses (i.e., over a 40 millisecond period), the puff actuated sensor sends a signal through a terminal


221


to the logic circuit


195


. The logic circuit


195


then sends a signal through an appropriate one of the terminals


211


-


218


to turn an appropriate one of the FET heater switches


201


-


208


ON.




Similarly, the cigarette sensor


57


is preferably turned on for a 1 millisecond duration every 10 milliseconds. If, for example, the cigarette sensor


57


detects four consecutive reflected pulses, indicating the presence of a cigarette


23


in the lighter


25


, the light sensor sends a signal through terminal


223


to the logic circuit


195


. The logic circuit


195


then sends a signal through terminal


225


to the puff-actuated sensor


45


to turn on the puff-actuated sensor. The logic circuit


195


also sends a signal through terminal


227


to the indicator


51


to turn it on. The above-noted modulation techniques reduce the time average current required by the puff actuated sensor


45


and the cigarette sensor


57


, and thus extend the life of the power source


37


.




The logic circuit


195


includes a PROM (programmable read-only memory)


301


, which includes preferably at least two data bases or “look-up tables”


302


and


304


, and optionally, a third data base (look-up table)


306


and possibly a fourth look-up table


307


. Each of the look-up tables


302


,


304


(and optionally


306


,


307


) converts a signal indicative of battery voltage v


in


to a signal indicative of the duty cycle (“dc


1


” for the first phase and “dc


2


” for the second phase) to be used in execution of the respective phase of the immediate power cycle. Third and fourth look-up tables


306


and


307


function similarly.




Upon initiation of a power cycle, the logic circuit receives a signal indicative of battery voltage v


in


, and then references the immediate reading v


in


to the first look-up table


302


to establish a duty cycle dc


1


for the initiation of the first phase of the power cycle. The first phase is continued until the timing network


197


provides a signal indicating that the predetermined time period of the first phase (t


phase 1


) has elapsed, whereupon the logic circuit


195


references v


in


and the second look-up table


304


and establishes a duty cycle dc


2


for the initiation the second phase. The second phase is continued until the timing network


197


provides a signal indicating that the predetermined time period of the second phase (t


phase 2


) has elapsed, whereupon the timing network


197


provides a shut-off signal to the logic circuit


195


at the terminal


229


. Optionally, the logic circuit


195


could initiate a third phase and establish a third duty cycle dc


3


, and the shut-off signal would not be generated until the predetermined period of the third phase (t


phase 3


) had elapsed. A similar regimen could optionally be established with a fourth phase (t


phase 4


). The present invention could be practiced with additional phases as well.




Although the present invention can be practiced by limiting reference to the look-up tables to an initial portion of each phase to establish a duty cycle to be applied throughout the substantial entirety of each phase, a refinement and the preferred practice is to have the logic circuit


195


configured to continuously reference v


in


together with the respective look-up tables


302


,


303


,


306


and


307


so as to dynamically adjust the values set for duty cycles in response to fluctuations in battery voltage as the control circuit progresses through each phase. Such device provides a more precise repetition of the desired thermo-histogram.




Other timing network circuit configurations and logic circuits may also be used, such as those described in the commonly assigned, U.S. Pat. Nos. 5,388,594; 5,505,214; 5,591,368; 5,499,636; and 5,372,148, all which are hereby incorporated by reference in their entireties.




During operation, a cigarette


23


is inserted in the lighter


25


and the presence of the cigarette is detected by the cigarette sensor


57


. The cigarette sensor


57


sends a signal to the logic circuit


195


through terminal


223


. The logic circuit


195


ascertains whether the power source


35




a


is charged or whether the immediate voltage is below an acceptable minimum v


in min


. If, after insertion of a cigarette


23


in the lighter


25


, the logic circuit


195


detects that the voltage of the power source


35




a


is too low, below v


in min


, the indicator


51


blinks and further operation of the lighter will be blocked until the power source


35




a


is recharged or replaced. Voltage of the power source


35




a


is also monitored during firing of the heater elements


37


and the firing of the heater elements


37


is interrupted if the voltage drops below a predetermined value.




If the power source


35




a


is charged and voltage is sufficient, the logic circuit


195


sends a signal through terminal


225


to the puff sensor


45


to determine whether a smoker is drawing on the cigarette


23


. At the same time, the logic circuit


195


sends a signal through the terminal


227


to the indicator


51


so that the LCD will display the digit “8”, reflecting that eight puffs are available.




When the logic circuit


195


receives a signal through terminal


221


from the puff-actuated sensor


45


that a sustained pressure drop or air flow has been detected, the logic circuit


195


sends a signal through terminal


231


to the timer network


197


to activate the timer network, which then begins to function phase by phase in the manner previously described. The logic circuit


195


also determines, by a downcount routine, which one of the eight heater elements is due to be heated and sends a signal through an appropriate terminal


211


-


218


to turn an appropriate one of the FET heater switches


201


-


208


ON. The appropriate heater stays on while the timer runs.




When the timing network


197


sends a signal through terminal


229


to the logic circuit


195


indicating that the timer has stopped running, the particular ON FET heater switch


211


-


218


is turned OFF, thereby removing power from the particular heater element


37


. The logic circuit


195


also downcounts and sends a signal to the indicator


51


through terminal


227


so that the indicator will display that one less puff is remaining (e,g., “7”, after the first puff). When the smoker next puffs on the cigarette


23


, the logic circuit


195


will turn ON another predetermined one of the FET heater switches


211


-


218


, thereby supplying power to another predetermined one of the heater elements. The process will be repeated until the indicator


51


displays “0”, meaning that there are no more puffs remaining on the cigarette


23


. When the cigarette


23


is removed from the lighter


25


, the cigarette sensor


57


indicates that a cigarette is not present, and the logic circuit


195


is reset.




Other features, such as those described in U.S. Pat. Nos. 5,505,214; 5,388,594; and 5,372,148 which are incorporated by reference, may be incorporated in the control circuitry


41


instead of or in addition to the features described above. For example, if desired, various disabling features may be provided. One type of disabling feature includes timing circuitry (not shown) to prevent successive puffs from occurring too close together, so that the power source


35




a


has time to recover. Another disabling feature includes means for disabling the heater elements


37


if an unauthorized product is inserted in the heater fixture


39


. For example, the cigarette


23


might be provided with an identifying characteristic that the lighter


25


must recognize before the heating elements


37


are energized.




Referring now to

FIG. 6

, the cigarette


23


, as constructed in accordance with the preferred embodiment of the present invention, comprises a tobacco rod


60


and a filter tipping


62


, which are joined together with tipping paper


64


. During manufacture of the cigarette, perforation holes


263


can be provided in one or more locations in the outer surface of the tobacco rod


60


.




The partially-filled, filler cigarette


23


preferably has an essentially constant diameter along its length and, which like more traditional cigarettes, is preferably between approximately 7.5 mm and 8.5 mm in diameter so that the smoking system


21


provides a smoker a familiar “mouth feel”. In the preferred embodiment, the cigarette


23


is approximately 62 mm in overall length, thereby facilitating the use of conventional packaging machines in the packaging of the cigarettes


23


. The combined length of the mouthpiece filter


94


and the free-flow filter


92


is preferably 30 mm. The tipping paper preferably extends approximately 6 mm over the tobacco rod


60


. The total length of the tobacco rod


60


is preferably 32 mm. Other proportions, lengths and diameters may be selected instead of those recited above for the preferred embodiment.




The tobacco rod


60


of the cigarette


23


preferably includes a tobacco web or mat


66


which has been folded into a tubular (cylindrical) form.




An overwrap


71


intimately enwraps the tobacco web


66


and is held together along a longitudinal seam as is common in construction of more traditional cigarettes. The overwrap


71


retains the tobacco web


66


in a wrapped condition about a free-flow filter


74


and a tobacco plug


80


.




Preferably, the cigarette overwrap paper


71


is wrapped intimately about the tobacco web


66


so as to render external appearance and feel of a more traditional cigarette. It has been found that a better tasting smoke is achieved when the overwrap paper


71


is a standard type of cigarette paper, preferably a flax paper of approximately 20 to 50 CORESTA (defined as the amount of air, measured in cubic centimeters, that passes through one square centimeter of material, e.g., a paper sheet, in one minute at a pressure drop of 1.0 kilopascal) and more preferably of about 30 to 45 CORESTA, a basis weight of approximately 23 to 35 grams per meter squared (g/m


2


) and more preferably about 23 to 30 g/m


2


, and a filler loading (preferably calcium carbonate) of approximately 23 to 35% by weight and more preferably 28 to 33% by weight. The overwrap paper


71


preferably contains little or no citrate or other burn modifiers, with preferred levels of citrate ranging from 0 to approximately 2.6% by weight of the overwrap paper


71


and more preferably less than 1%.




The tobacco web


66


itself preferably comprises a base web


68


and a layer of tobacco material


70


located along the inside surface of the base web


68


. At the tipped end


72


of the tobacco rod


60


, the tobacco web


66


together with the overwrap


71


are wrapped about the tubular free-flow filter plug


74


. The free-flow filter


74


(also known in the art as “whistle-through” plugs) provides structural definition and support at the tipped end


72


of the tobacco rod


60


and permits aerosol to be withdrawn from the interior of the tobacco rod


60


with a minimum pressure drop. The free-flow filter


74


also acts as a flow constriction at the tipped end


72


of the tobacco rod


60


, which is believed to help promote the formation of aerosol during a draw on the cigarette


23


. The free-flow filter is preferably at least 7 millimeters long to facilitate machine handling and is preferably annular, although other shapes and types of low efficiency filters are suitable, including cylindrical filter plugs.




At the free end


78


of the tobacco rod


60


, the tobacco web


66


together with the overwrap


71


are wrapped about a cylindrical tobacco plug


80


. Preferably, the tobacco plug


80


is constructed separately from the tobacco web


66


and comprises a relatively short column of cut filler tobacco that has been wrapped within and retained by a plug wrap


84


.




Preferably the tobacco plug


80


is constructed on a conventional cigarette rod making machine wherein cut filler (preferably blended) is air formed into a continuous rod of tobacco on a traveling belt and entrapped with a continuous ribbon of plug wrap


84


which is then glued along its longitudinal seam and heat sealed. In accordance with the preferred embodiment of the present invention, the plug wrap


84


is preferably constructed from a cellulosic web of little or no filler, sizing or burn additives (each at levels below 0.5% weight percent) and preferably little or no sizing. Preferably, the tobacco plug wrap


84


has a low basis weight of below 15 grams per meter squared and more preferably about 13 grams per meter squared. The tobacco plug wrap


84


preferably has a high permeability in the range of about 20,000 to 35,000 CORESTA and more preferably in the range of about 25,000 to 35,000 CORESTA, and is constructed preferably from soft wood fiber pulp, abaca-type cellulose or other long fibered pulp. Such papers are available from Papierfabrik Schoeller and Hoescht GMBH, Postfach 1155, D-76584, Gernsback, GERMANY; another paper suitable for use as the plug wrap


84


is the paper TW 2000 from DeMauduit of Euimperle FRANCE, with the addition of carboxy-methyl cellulose at a 2.5 weight percent level.




The tobacco rod making machine is operated so as to provide a tobacco rod density of approximately 0.17 to 0.30 grams per cubic centimeter (g/cc), but more preferably in a range of at least 0.20 to 0.30 g/cc and most preferably between about 0.24 to 0.28 g/cc. The elevated densities are preferred for the avoidance of loose ends at the free end


78


of the tobacco rod


60


. However, it is to be understood that the lower rod densities will allow the tobacco column


82


to contribute a greater proportion of aerosol and flavor to the smoke. Accordingly, a balance must be struck between aerosol delivery (which favors a low rod density in the tobacco column


82


) and the avoidance of loose-ends (which favors the elevated ranges of rod densities).




The tobacco column


82


preferably comprises cut filler of a blend of tobaccos typical of the industry, including blends comprising bright, burley and oriental tobaccos together with, optionally, reconstituted tobaccos and other blend components, including traditional cigarette flavors. However, in the preferred embodiment, the cut filler of the tobacco column


84


comprises a blend of bright, burly and oriental tobaccos at the ratio of approximately 45:30:25 for the U.S. market, without inclusion of reconstituted tobaccos or any after cut flavorings. Optionally, an expanded tobacco component might be included in the blend to adjust rod density, and flavors may be added.




The continuous tobacco rod formed as described above is sliced in accordance with a predetermined plug length for the tobacco plug


80


. This length is preferably at least 7 mm in order to facilitate machine handling. However, the length may vary from about 7 mm to 25 mm or more depending on preferences in cigarette design which will become apparent in the description which follows, with particular reference to FIG.


7


.




As a general matter, the length of the tobacco plug


80


is preferably set relative to the total length of the tobacco rod


60


such that a void


91


is defined along the tobacco rod


60


between the free-flow filter


74


and the tobacco plug


80


. The void


91


corresponds to an unfilled portion of the tobacco rod


60


and is in immediate fluid communication with the tipping


62


through the free flow filter


74


of the tobacco rod


60


.




Referring particularly to

FIG. 6

, the length of the tobacco plug


80


and its relative position along the tobacco rod


60


is also selected in relation to features of the heater elements


37


. When a cigarette is properly positioned against a stop


182


within the lighter


25


, a portion


93


of each heater element


37


will contact the tobacco rod


60


along a region of the tobacco rod


60


. This region of contact is referred to as a heater footprint


95


. The heater footprint


95


(as shown with a double arrow in

FIG. 2

) is not part of the cigarette structure itself, but instead is a representation of that region of the tobacco rod


60


where the heater element


37


would be expected to reach operative heating temperatures during smoking of the cigarette


23


. Because the heating elements


37


are a fixed distance


96


from the stop


182


of the heater fixture, the heater foot print


95


consistently locates along the tobacco rod


60


at the same predetermined distance


96


from the free end


78


of the tobacco rod


60


for every cigarette


23


that is fully inserted into the lighter


25


.




Preferably, the length of the tobacco plug


80


, the length of the heater footprint


95


and the distance between the heater footprint


95


and the stop


182


are selected such that the heater footprint


95


extends beyond the tobacco plug


80


and superposes a portion of the void


91


by a distance


98


. The distance


98


by which the heater footprint


95


superposes the void


91


(the unfilled portion of the tobacco rod


60


) is also referred to as the “heater-void overlap”


98


. The distance by which the remainder of the heater footprint


95


superposes the tobacco plug


80


is referred to as the “heater-filler overlap”


99


.




The tipping


62


preferably comprises a free-flow filter


92


located adjacent the tobacco rod


60


and a mouthpiece filter plug


94


at the distal end of the tipping


62


from the tobacco rod


60


. Preferably the free-flow filter


92


is tubular and transmits air with very little pressure drop. Other low efficiency filters of standard configuration could be used instead, however. The inside diameter for the free flow filter


92


is preferably at or between 2 to 6 millimeters and is preferably greater than that of the free flow filter


74


of the tobacco rod


60


.




The mouthpiece filter plug


94


closes off the free end of the tipping


62


for purposes of appearance and, if desired, to effect some filtration, although it is preferred that the mouthpiece filter plug


94


comprise a low efficiency filter of preferably about 15 to 25 percent efficiency.




The free-flow filter


92


and the mouthpiece filter plug


94


are preferably joined together as a combined plug with a plug wrap


101


. The plug wrap


101


is preferably a porous, low weight plug wrap as is conventionally available to those in the art of cigarette making. The combined plug is attached to the tobacco rod


60


by the tipping paper


64


of specifications that are standard and conventionally used throughout the cigarette industry. The tipping paper


64


may be either cork, white or any other color as decorative preferences might suggest.




Preferably, a cigarette


23


constructed in accordance with the preferred embodiment has an overall length of approximately 62 mm, of which 30 mm comprises the combined plug of the tipping


62


. Accordingly, the tobacco rod


60


is 32 mm long. Preferably, the free-flow filter


74


of the tobacco rod


60


is at least 7 mm long and the void


91


between the free-flow filter


74


and the tobacco plug


80


is preferably at least 7 mm long. In the preferred embodiment, the heater foot print


95


is approximately 12 mm long and located such that it provides a 3 mm heater-void overlap


98


, leaving 9 mm of the heater foot print


95


superposing the tobacco plug


80


.




It is to be understood that the length of the void


91


, the length of the tobacco plug


80


, and the distribution of the perforation holes


263


may be adjusted to facilitate manufacturing and more importantly, to adjust the smoking characteristics of the cigarette


23


, including adjustments in its taste, draw and delivery. The pattern of holes


263


, the length of the void


91


and the amount of heater-filler overlap (and heater-void overlap) may also be manipulated to adjust the immediacy of response, to promote consistency in delivery (on a puff-to-puff basis as well as between cigarettes) and to control condensation of aerosol at or about the heaters.




In the preferred embodiment, the void


91


(the filler-free portion of the tobacco rod


60


) extends approximately 7 mm to assure adequate clearance between the heater foot print


95


and the free-flow filter


74


. In this way, margin is provided such that the heater foot print


95


does not heat the free-flow filter


74


during smoking. Other lengths are suitable, for instance, if manufacturing tolerances permit, the void


91


might be configured as short as approximately 4 mm or less, or in the other extreme, extended well beyond 7 mm so as establish an elongate filler-free portion along the tobacco rod


60


. The preferred range of lengths for the filler-free portion (the void


91


) is from approximately 4 mm to 18 mm and more preferably 5 to 12 mm.




Referring to

FIG. 7

, a preferred method of manufacturing cigarettes


23


in accordance with a preferred embodiment of the present invention may initiate with the production of a plug comprising a multiple of tobacco plugs


80


, preferably in a 2-up configuration and enwrapped with the plug wrap


84


.




It is to be understood that reference to a 2-up tobacco plug


80


refers to a plug construction such that if it were divided into two pieces, would render two complete tobacco plugs


80


of the preferred cigarette


23


. Likewise, a 2-up tipping plug


62


, if separated into 2 pieces, would provide a pair of tippings


62


, each comprising free-flow filter


92


, a mouth piece filter


94


and a plug wrap


84


as described in connection with the partially-filled cigarette


23


of the preferred embodiment. As a further example, a 2-up tobacco rod plug


60


, if severed, would render two complete tobacco rods


60


.




Referring back to

FIG. 7

, production of the 2-up tobacco rod plugs


60


initiates with the construction of 2-up tobacco plugs


80


and the establishment of a supply of 12-up free-flow filter plugs


74


.




Preferably the tobacco plug


80


is constructed on a conventional cigarette rod making machine


122


(such as a Molins Mark 9 tobacco rod maker) wherein cut filler (preferably blended) is air formed into a continuous rod of tobacco on a traveling belt and enwrapped with a continuous ribbon of plug wrap


84


which is then glued along its longitudinal seam and heat sealed. The output of the tobacco rod maker


122


is then cut at a cutter


124


and delivered by a suitable arrangement


126


to a first hopper


128


of a combining machine such as a Molins double-action plug-tube combiner. The delivery arrangement


126


may include a HCF tray filler or some other equally suitable arrangement to load the first hopper


128


with the 4-up tobacco plugs


80


. Other suitable plug delivery systems might be employed such as mass flow conveyors or pneumatic tubes or the like.




Similarly, the 12-up free-flow filter plugs


74


are produced in continuous fashion from a tubular filter rod maker


130


, such as with a maker as described in U.S. Pat. No. 3,637,447 to Berger et al, particularly at column 4. The continuous rod of tubular filter material from the rod maker


130


is cut at a cutter


132


into the 12-up free-flow filter plugs


74


and delivered to a second hopper


134


of the Molins double-action plug-tube combiner (“DATPC ”) via a suitable delivery arrangement


136


which preferably comprises a HCF tray filler, although other delivery arrangements as previously described might be used instead.




The 12-up free-flow filter plugs


74


from the second hopper


134


are cut into six 2-up free-flow filter plugs


74


and the 4-up tobacco plugs from the first hopper


128


are cut into two 2-up tobacco plugs


80


. These 2-up tobacco plugs


80


and 2-up free-flow filter plugs


74


are then placed in alternating relation to one another upon a conveyor


140


leading to a garniture belt


142


. Such mechanical action can be provided at the front end of a Molins DAPTC combiner. The spacing between the 2-up tobacco plugs


80


and the 2-up free-flow filter plugs


74


is set to equal the desired amount of void


91


desired in the tobacco rod


60


of the cigarette


23


being produced.




In most Molins DAPTC combiners, this spacing


91


between the 2-up plugs on the conveyor


140


is set precisely with a collator/spacer drum


139


located at or about the location where the compression belt


141


and the garniture belt


142


receive the 2-up free-flow filter plugs


74


and the 2-up tobacco plugs


80


. Other suitable arrangements for assuring proper placement of the 2-up plugs


74


and the 2-up tobacco plugs


80


would be readily apparent to one of ordinary skill in the art of combining plugs.




Just upstream of the garniture belt


142


, a continuous ribbon of tobacco web


66


is reeled from a bobbin


144


through a series of slack and tension controlling rollers generally designated


146


and past a glue applicator


148


prior to its arrival at the final roller


150


, which then directs the ribbon of tobacco web


66


toward the path of the garniture belt


142


.




Likewise, a continuous ribbon of overwrap


71


is reeled from a bobbin


152


through an arrangement for adjusting slack and/or tension in the ribbon


71


generally designated


154


, past a plurality of glue applicators


156


and then about a final roller


158


which directs the ribbon of overwrap


71


toward the path of the garniture belt


142


and between the garniture belt


142


and the tobacco web


66


.




During passage through the garniture


160


, the continuous ribbon of tobacco web


66


and the overwrap


71


are folded about the spaced apart 2-up tobacco plugs


80


and the 2-up free-flow filter plugs


74


to produce a continuous rod


162


which is then cut at the cutter head of the DAPTC machine to produce tobacco rod portions


164


. The cutter head


166


is arranged to cut every other 2-up tobacco plug


80


so as to produce 2-up tobacco rods


164


having a 1-up tobacco plug


80


at opposite ends thereof and a 2-up free-flow filter


74


separated from the tobacco plugs


80


by spaces


91


. The 2-up tobacco rods


164


are delivered from the output of the combining machine to a drum link-up assembly


220


which cuts the 2-up tobacco rods in half to form tobacco rods of unit length and delivers the cut tobacco rods to an assembly drum of the tipping apparatus.




The apparatus according to the invention eliminates the need to load cut tobacco rods into a hopper of a tipping machine and thereby minimizes damage which could occur to the tobacco rods during transport through such a hopper system. For instance, commonly-owned U.S. Pat. No. 5,666,976 discloses an arrangement wherein 4-up tobacco rods are delivered to a tray filler and then to a hopper of a tipping machine wherein the 4-up tobacco rods are transported through a series of drums which effect cutting of the 4-up tobacco rods into 2-up tobacco rods and then into 1-up tobacco rods. Such an arrangement exposes the 4-up tobacco rods to mechanical abrasion which can damage the tobacco rods. The apparatus according to the invention obviates the need for a hopper to receive the tobacco rods since the output of the combining apparatus wherein the tobacco rods are manufactured is directly linked to the tipping machine by the drum link-up assembly.




The DAPTC machine shown in

FIG. 7

, is hard-linked to the cigarette tipping machine


200


(shown in

FIG. 9

) by the drum link-up assembly


220


. The drum link-up assembly can be comprised of a plurality of drums in any suitable arrangement. A preferred arrangement which allows optional laser perforation of the tobacco rod is shown in FIG.


9


. It should be appreciated that this connection between the DAPTC machine and the tipping machine


200


, allows for a smooth transition from the DAPTC to the tipping machine


200


in a quick and efficient manner.




Referring back to the garniture


160


of FIG.


7


and in specific reference to

FIGS. 8A-8E

, as the various components of the tobacco rod


60


are pulled through the garniture


160


, a progression of folding steps wraps the continuous ribbon of tobacco mat


66


and the continuous ribbon of overwrap


71


about the alternating succession of 2-up plugs


80


and


74


.




Referring now to

FIG. 8A

, upon their arrival at the garniture belt


142


, the plugs


74


and


80


, the tobacco web


66


and the overwrap


71


are urged against one another and the garniture belt


142


by the compression belt


141


. A continuous bead of adhesive


172


is located at or about the center region of the continuous ribbon of tobacco web


66


as applied by the glue applicator


148


. This bead of adhesive


172


anchors the 2-up tobacco plugs


80


and 2-up free-flow filter plugs


74


to the ribbon of tobacco web


66


.




Likewise, a glue applicator can be used to lay down intermittent beads of adhesive or plural glue applicators


156


can be used to lay down continuous beads of adhesive


174


,


176


and


178


on the side


180


of the continuous ribbon of overwrap


71


which is to come into contact with the continuous ribbon of tobacco web


66


at the garniture


160


. It is preferred that these “laminating” beads of adhesive


174


,


176


and


178


are not allowed to set prior to entry into the garniture


160


so the tobacco web


66


and the overwrap


71


may slip slightly relative to one another as they are folded about the 2-up plugs


80


and


74


in the garniture


160


. This provision for at least some “give” avoids breaks and tears in the materials.




Referring now to

FIGS. 8B and 5C

, the garniture


160


progressively folds the continuous ribbon of tobacco web


66


, together with the continuous ribbon of overwrap


71


about the 2-up plugs


74


and


80


. It is to be noted that the relative placements of the tobacco web


66


and the overwrap


71


are slightly offset from one another so that along one side of the plugs


74


and


80


an edge portion


182


of the overwrap


71


extends only slightly beyond the adjacent edge of the tobacco mat


66


, preferably at about 1 millimeter or so, whereas along an opposite side of the plugs


74


and


80


, an edge portion


384


of the overwrap


71


extends at least several millimeters beyond the adjacent edge of the tobacco web


66


. Such provision allows for the application of a bead of adhesive along the edge portion


184


by a glue applicator


186


as shown in

FIG. 8D

, prior to the edge portion


184


being folded completely down and over the plugs


74


and


80


as shown in

FIG. 8E

to form a seam


189


.




It is to be noted that the tobacco web


66


is folded such and its width is selected such that it does not overlap upon itself at its seam


188


. Preferably, no adhesive is applied at or about the seam


188


of the tobacco web


66


so as to minimize the application of adhesive to the structure of the tobacco rod structure


60


.




It has also been found effective to locate the laminating adhesive beads


174


,


176


and


178


at 4 o'clock, 6 o'clock and 8 o'clock positions relative to the cross-sectional form of the 2-up plugs


74


and


80


at the garniture


160


.




The preferred adhesive for all adhesive beads


174


,


176


,


178


,


172


and


190


is a liquid starch adhesive such as obtainable from National Starch. The bead of adhesive


190


is sufficiently strong enough to retain the tobacco web


66


in its completely folded condition.




According to a preferred embodiment, the output of the combining apparatus is a 2-up tobacco rod plug


164


which is directly linked to a catch drum


222


of the drum link-up assembly


220


at the entrance to a cigarette tipping machine


200


such as a Hauni Max that has been modified to operate in the manner as described with reference to

FIGS. 10A and 10B

. A preferred layout of the modified Hauni Max is shown in FIG.


9


. However, other tipping machines or the like could be arranged to execute the steps of cigarette manufacture that are described below.




Referring now to FIGS.


9


and


10


A-


10


B, a hopper


192


of the tipping machine


200


receives 4-up tipping plugs


62


which are the product of a combining operation


194


(FIG.


10


A), wherein 2-up free-flow filter plugs


92


from a tubular filter rod maker


196


and 2-up mouthpiece filter plugs


94


from another filter rod maker


198


, such as a KDF-2, are combined, together with plug wrap


84


, to produce the aforementioned 4-up tipping plugs


62


(a plug which when severed into four pieces provides four tippings


62


, each comprising a free-flow filter


92


, a mouthpiece filter


94


and plug wrap


84


). The 4-up tipping plugs


62


are delivered to the hopper


192


of the tipping machine


200


by suitable delivery arrangement.




The description of further steps in the preferred method of producing the cigarettes


23


will now be described with reference to the relative movement and position of the cigarette components as shown in

FIGS. 10A-10B

, with cross-reference to respective drum stations along the mechanical pathway of the machine


200


as shown in FIG.


9


.

FIGS. 10A-10B

include dashed lines that bear designations which correlate to drums in the machine


200


of the same designation.




The 2-up tobacco rod portions


164


are transferred directly from the combining apparatus to the drum link-up assembly


220


. In the embodiment shown in

FIG. 9

, the 2-up tobacco rods are transferred to a catch drum


222


of the drum link-up assembly. The drums of the drum link-up assembly include flutes for receiving tobacco rods and vacuum arrangements which apply vacuum to the flutes at rotational positions of the drums where it is desired to hold the tobacco rods via suction. The vacuum is terminated at rotational positions of the drum where it is desired to release the tobacco rods for transfer to an adjacent drum. To facilitate transfer of the tobacco rods from one drum to another, the drums rotate in opposite directions, i.e., a tobacco rod traveling in a clockwise direction on one drum is picked up by an adjacent drum rotating in a counterclockwise direction after which the tobacco rod is picked up by a drum rotating in a clockwise direction and so on.




As shown in

FIG. 9

, the next member to receive the tobacco rods


60


from the catch drum


222


is a transfer drum


224


which transfers the tobacco rods onto the next component. The main purpose of the transfer drum


224


is to properly orient the tobacco rods


164


to be transferred to the next component. Another purpose of the transfer drum is to allow the tobacco rods to be properly passed so a desired delivery of the tobacco rods may be achieved due to the rotation of the various drums. For example, the drum


232


in

FIG. 9

currently is rotating in a counterclockwise direction.




Next, the tobacco rods are transferred to a swash-plate drum


226


. The main purpose of the swash-plate drum


226


is to center the tobacco rods, and to properly align the tobacco rods, before the tobacco rods are transferred to the next component.




Subsequently, the tobacco rods are transferred to a laser drum


228


which can be used to form perforations on the tobacco rods. The laser drum


228


may be set up as needed by the user to create perforations either circumferentially or longitudinally, but in the preferred method the perforations are positioned circumferentially. Any type of laser system may be used that can accomplish the objective of creating perforations. However, the perforations can be omitted or formed by another suitable technique.




After passing around the laser drum


228


, the tobacco rods are transferred to a cutting drum


230


, wherein the tobacco rods are cut by a cutter (not shown). In the preferred apparatus, the tobacco rods are cut by a cutter which is rotating in a direction opposite to that of the cutting drum


230


. Preferably, the cutter cuts the tobacco rods in half from a 2-up 64 mm tobacco rod to two 32 mm tobacco rods


60


,


60


′.




After the tobacco rods


60


,


60


′ are cut, to a length desired by the user, the tobacco rods


60


,


60


′ are transferred to a separator drum


232


. The primary purpose of the separator drum


232


is to separate the two tobacco rods


60


,


60


′ to create a space between the two tobacco rods


60


,


60


′ so that a 2-up tipping plug


62


may be placed in between the two tobacco rods


60


,


60


′.




The tipping plugs are combined with the tobacco plugs as follows. First, 4-up tipping plugs


62


from the hopper


192


are delivered onto a third cutting drum


242


and cut into two, 2-up tipping plugs


240


and


240


′. Each 2-up tipping plug


240


comprises a 1-up free-flow filter


92


at one end, a centrally located 2-up mouthpiece filter


94


and another 1-up free-flow filter


92


at the other end of the 2-up tipping plug


240


.




The 2 two-up tipping plugs


240


and


240


′ are then graded at a grading drum


244


and aligned on a alignment drum


246


. The aligned two-up tipping plugs


240


and


240


′ are then transferred through an accelerator drum


248


onto a central portion of the assembly drum


238


so as to locate the 2-up tipping plugs


240


and


240


′ centrally between the pairs of separated tobacco plugs


60


,


60


′. At the conclusion of this operation, on each flute of the assembly drum


238


, the free ends of the free-flow filters


92


of a 2-up tipping plug face the free-flow filters


74


of a separated pair of tobacco rods


60


′.




Next, the aforementioned components placed at the assembly drum


238


are transferred to a swash-plate drum


250


whose outer rail pushes the associated pairs of tobacco rods


60


,


60


′ into abutting relationship with the respective 2-up tipping plug


240


situated therebetween. Meanwhile, a continuous ribbon of tipping paper is drawn from a bobbin


254


and directed through a glue applicator


255


and severed into double-wide pieces


256


at a cutter


257


. Once the cigarette components are positioned by the swash plate, an edge-portion of a double-wide piece of tipping paper


64


is attached to the respective 2-up tipping plug


240


and abutting portions of the pair of tobacco rods


60


,


60


′ so as to initiate connection of these components to form 2-up cigarette rods


252


. The tipping operation is then continued on a roll drum


260


which rolls the double-wide pieces of tipping paper


256


about the 2-up cigarette rods


252


. The 2-up cigarette rods


252


are then transferred to drum


261


, wherein a plurality of perforations are optionally created on the 2-up cigarette rods


252


. In the preferred embodiment, the perforations


263


are created by a laser system. The perforations


263


are oriented circumferentially around the cigarette rods


252


, and are preferably located anywhere from 4 mm to 20 mm, e.g. 4 to 12 mm from the free end


15


of the cigarette such that the perforations extend into the tobacco plugs


80


. The rods


252


are then cut in two at a final cut drum


262


to produce a pair of cigarettes


23


and


23


′ from each of the rods


252


. At a turning drum


264


, one of the cigarettes


23


is turned and aligned with the other cigarette


23


′.




The continuous stream of cigarettes


23


produced from the tipping machine


200


is then directed to packers


266


and cartoners


268


and finally case packers


270


for shipment from the manufacturing facilities.




It will be understood that any type of perforating system can be used to perforate the tobacco rods prior to being attached to the filter rods and/or after the tobacco rods are attached to the filter rods. A preferred perforating system is a laser perforating system, many forms of which are available commercially.

FIG. 11

shows a perspective side view of portions of a Hauni 500 laser perforating system which is commercially available from Hauni Maschinenbau AG, located in Hamburg, Germany. According to the invention, the laser system can be used to burn perforation holes in tobacco rods at a location in the drum link-up assembly


220


located between a combining apparatus and a tipping apparatus. In addition, another Hauni 500 laser system can be used to burn perforation holes in a tobacco rod of a completed cigarette at a location near the exit of the tipping apparatus.




As shown in

FIG. 11

, the laser perforating apparatus


298


includes the laser perforating drum


228


, flutes


302


for holding tobacco rods (or completed cigarettes in the case where the laser perforating apparatus is located in the tipping apparatus), rolling cams


304


which engage the rods/cigarettes located in the flutes


304


so as to roll the rods/cigarettes from a first portion of the flute to a second portion of the flute (see FIG.


13


), and a laser beam directing device


306


which splits a laser beam into two beams for perforating two locations on the tobacco rods/cigarettes. The preferred location for burning the perforating holes in the 2-up tobacco rods passing through the drum link-up apparatus


220


(or in the tobacco rods of the completed cigarettes) is with an area located 4 to 20 mm from the end of the tobacco rod at which the tobacco plug


80


is located. With reference to

FIG. 6

, the perforating holes


263


thus formed will pass through the tobacco rod outer overwrap


71


, the tobacco mat


66


, the overwrap


84


surrounding the tobacco plug


80


and into the tobacco plug


80


.





FIG. 12

is a perspective view of the apparatus shown in

FIG. 11

but from an opposite side thereof. As shown in

FIG. 12

, the laser beam directing device


306


includes a focusing device


308


wherein a plurality of beams are focused on an individual tobacco rod


164


. Further details of the focus device


308


can be seen in

FIGS. 13 and 14

. As shown in

FIG. 13

, the focusing device directs a focused laser beam


310


onto the tobacco rod


164


as the tobacco rod is rotated about its axis along the surface of the flute


302


by the rolling cam


304


. The laser (not shown) is actuated by a controller (not shown) which is programmed to deliver a pulsed beam during rotation of the tobacco rod in the flute after which the beam is shut off until the next tobacco rod is in a location suitable for perforation by the beam.

FIG. 14

shows a beam


312


from the laser (not shown), a first mirror


314


for deflecting a portion of the beam


312


to a first lens


316


, and a second mirror


318


for deflecting a second portion of the beam


312


to a second lens


320


. As a result, the beam splitter arrangement shown in

FIG. 14

directs a pair of beams onto the 2-up tobacco rod


164


at locations near the free ends thereof.




The laser system can be set up to provide any desired perforation hole pattern in the tobacco rods. According to a preferred embodiment, the laser is programmed to burn 12 to 24 holes having a width of about 0.06 mm into the outer surface of each tobacco rod. The holes can be provided in a single row or multiple rows extending around the circumference of the tobacco rod and depending on the length of the laser pulse width (the amount of time the laser is in the “on” portion of a pulse cycle), the length of the holes in the circumferential direction can vary accordingly. Further, the row or rows can be provided at longitudinally spaced apart locations along the tobacco rod. For example, a row of perforations could be provided at a location about 4 mm from the end of the tobacco rod and another row of perforations could be provided at a location about 7 to 12 mm from the end. Moreover, by focusing the beam such that the focal point is inside the tobacco rod, a pair of adjacent holes can be burned into the tobacco rod during each pulse of the laser, i.e., a single beam focused in this way can provide a double row of perforations extending around the tobacco rod.




In terms of operational parameters, the laser system should be capable of penetrating the outer layers of the tobacco rod and provide a desired pattern of holes while the tobacco rods travel through the drum link-up assembly at speeds capable of producing over 4000 rods/cigarettes per minute. As an example, a 300 watt laser having a pulse duration of 1000 μs can be operated with a pulse width of 200 to 400 μs (the amount of time the laser is “on” during the pulse duration) to obtain a single or double row of perforations in a 2-up tobacco rod traveling through the drum link-up assembly at a speed sufficient to produce 5000 cigarettes per minute. In such a system, a double row of 24 perforations with 12 perforations in each row can be obtained using a pulse width of 400 μs. However, the actual power settings used will depend on the particular laser system and the set-up associated therewith.





FIG. 15

shows a schematic layout of a combining apparatus (DAPTC)


400


, a link-up


402


, a first laser perforating station


404


, a tipping apparatus (MAX S)


406


, a second laser perforating station


408


, and a conveying apparatus


410


for transporting, loading and packaging the finished cigarettes. As shown, the DAPTC


400


conveys tobacco rods in a direction perpendicular to the direction in which the tobacco rods are attached to filter rods in the tipping apparatus.




It is to be understood that the present invention may be embodied in other specific forms and process the use without departing from the spirit or essential characteristics of the present invention. For example, the cutting and slitting operations may be reconfigured to cut different multiples of plugs. Although the disclosure specifies certain machines as being preferred, one of ordinary skill in the art, once familiar with these teachings, would be able to select other machines for executing the disclosed process. Additionally, certain plug structures might be altered such as replacing tubular plugs with those that may have a filled central portion. Thus, while the invention has been illustrated and described in accordance with various preferred embodiments, it is recognized that variations and changes may be made therein without departing from the invention as set forth in the claims.



Claims
  • 1. An electrical smoking system comprising:a cigarette comprising a tubular tobacco mat partially filled with tobacco material so as to define a filled tobacco rod portion and an unfilled tobacco rod portion, said filled tobacco rod portion being adjacent a free end of said cigarette; and a lighter comprising an electrical heater element and a system for electrically actuating said heater element, said lighter arranged to at least partially receive said cigarette; said cigarette and said lighter being mutually arranged so that when the cigarette is received in said lighter, said electrical heater element of the lighter at least partially superposes at least a portion of the filled tobacco rod portion; said cigarette and said lighter being mutually arranged so that when the cigarette is received in said lighter, said free end of said cigarette is occluded; said cigarette including a zone of perforations at a first location along said filled tobacco rod portion; said cigarette being free of perforations along said unfilled tobacco rod portion.
  • 2. The electrical smoking system as claimed in claim 1, wherein said lighter further comprises an air admission passage and an arrangement operative at a location along said air admission passage to produce a pressure drop in the range of 10 to 40 mm water.
  • 3. The electrical smoking system as claimed in claim 2, wherein said lighter further comprises a puff sensor having a sensitivity to a change in pressure in the range of 10 to 40 mm water.
  • 4. The system as claimed in claim 1, said lighter further comprising an air admission passage and an arrangement operative at a location along said air admission passage to produce a pressure drop in the range of 20 to 30 mm water.
  • 5. The system as claimed in claim 4, said lighter further comprising a puff sensor having a sensitivity to a change in pressure in the range of 20 to 30 mm water.
  • 6. The system as claimed in claim 5, wherein said cigarette has a resistance to draw of approximately 20 to 25 mm water.
  • 7. The system as claimed in claim 4, wherein said lighter further comprises an air flow deflector arranged to direct air drawn into said lighter toward a cigarette receiving location within said lighter, the air flow deflector directing the air in a circumferential zone around the cigarette at the location of the zone of perforations.
  • 8. The system as claimed in claim 7, wherein at least a portion of said lighter adjacent said cigarette receiving location is constructed of a metal, including at least said air flow deflector.
  • 9. The system as claimed in claim 1, wherein said lighter further comprises a flow deflector arranged to direct air drawn into said lighter toward a cigarette receiving location within said lighter, the air flow deflector directing the air in a circumferential zone around the cigarette at the location of the zone of perforations.
  • 10. The system as claimed in claim 9, wherein at least a portion of said lighter adjacent said cigarette receiving location is constructed of a metal, including at least said air flow deflector.
  • 11. A cigarette of an electrical smoking system, comprising a tobacco rod and a filter tipping attached to a tipped end portion of said tobacco rod, said tobacco rod comprising:a tubular tobacco mat partially filled with tobacco material so as to define a filled tobacco rod portion and an unfilled tobacco rod portion, said filled tobacco rod portion being adjacent a free end of said cigarette; said cigarette including a zone of perforations at a first location along said filled tobacco rod portion; said cigarette being free of perforations along said unfilled tobacco rod portion.
  • 12. The cigarette as claimed in claim 11, said tobacco rod further comprising a cigarette wrapper disposed about said tubular tobacco mat, said perforations extending at least partially through said wrapper and said mat.
  • 13. The cigarette as claimed in claim 12, wherein said cigarette is adapted to receive thermal treatment along a length portion of said tobacco rod corresponding to a heater footprint of an electrical lighter, said length portion spaced a predetermined distance from said free end portion of said tobacco rod, said first location of said zone of perforations being spaced from said free end of said tobacco rod a first distance approximately equal to said predetermined distance.
  • 14. The cigarette as claimed in claim 12, wherein said cigarette is adapted to receive thermal treatment along a length portion of said tobacco rod corresponding to a heater footprint of an electrical lighter, said length portion spaced a predetermined distance from said free end portion of said tobacco rod, said first location of said zone of perforations being spaced from said free end of said tobacco rod a first distance greater than said predetermined distance.
  • 15. The cigarette as claimed in claim 12, wherein said cigarette is adapted to receive thermal treatment along a length portion of said tobacco rod corresponding to a heater footprint of an electrical lighter, said length portion spaced a predetermined distance from said free end portion of said tobacco rod, said first location of said zone of perforations being spaced from said free end of said tobacco rod a first distance less than said predetermined distance.
  • 16. The cigarette as claimed in claim 12, further comprising a plurality of circumferentially spaced-apart holes in said tubular tobacco mat at a second location along said filled tobacco rod portion, said wrapper covering said mat holes.
  • 17. The cigarette as claimed in claim 16, wherein said tubular tobacco mat comprises a tubular base web and a layer of tobacco material disposed along an interior of said tubular base web;said mat holes extending through said base web and said layer of tobacco material.
  • 18. The cigarette as claimed in claim 16, wherein said mat holes are approximately 1 mm in diameter and 6 in number, arranged in a row and said zone of perforations comprises one or two rows of perf-holes, each row having 12 perf-holes.
  • 19. The cigarette as claimed in claim 16, wherein said second location of mat holes is spaced from said free end of said tobacco rod a second distance of approximately 7 mm and said zone of perforations comprises at least one row of 12 perf-holes spaced approximately 12 mm from said free end.
  • 20. The cigarette as claimed in claim 16, wherein a second perforation zone is established at a third location along said tobacco rod;said second location of mat holes being between said first and third locations, said second location of mat holes is optionally spaced from said free end of said tobacco rod a first distance of approximately 7 mm and said perforation zones are optionally spaced from said free end of said tobacco rod approximately 4 and 12 mm, respectively.
  • 21. The cigarette as claimed in claim 11, said tobacco rod further comprising a cigarette wrapper disposed about said tubular tobacco mat, said perforations extending at least partially through said wrapper and said mat.
  • 22. The cigarette as claimed in claim 21, wherein said cigarette is adapted to receive thermal treatment along a length portion of said tobacco rod corresponding to a heater footprint of an electrical lighter, said length portion spaced a predetermined distance from said free end portion of said tobacco rod, said first location of said zone of perforations being spaced from said free end of said tobacco rod a first distance approximately equal to said predetermined distance.
  • 23. The cigarette as claimed in claim 21, wherein said cigarette is adapted to receive thermal treatment along a length portion of said tobacco rod corresponding to a heater footprint of an electrical lighter, said length portion spaced a predetermined distance from said free end portion of said tobacco rod, said first location of said zone of perforations being spaced from said free end of said tobacco rod a first distance greater than said predetermined distance.
  • 24. The cigarette as claimed in claim 21, wherein said cigarette is adapted to receive thermal treatment along a length portion of said tobacco rod corresponding to a heater footprint of an electrical lighter, said length portion spaced a predetermined distance from said free end portion of said tobacco rod, said first location of said zone of perforations being spaced from said free end of said tobacco rod a first distance less than said predetermined distance.
  • 25. The cigarette as claimed in claim 21, wherein a second perforation zone is established at a third location along said tobacco rod;a second location of mat holes in said tubular tobacco mat being between said first and third locations, said second location of mat holes is optionally spaced from said free end of said tobacco rod a first distance of approximately 7 mm and said perforation zones are optionally spaced from said free end of said tobacco rod approximately 4 and 12 mm, respectively.
  • 26. The cigarette as claimed in claim 11, wherein said tobacco rod includes a tubular body at the tipped end portion of the tobacco rod; andsaid filter tipping includes a free flow filter adjacent said tubular body and a mouthpiece filter adjacent said free flow filter.
  • 27. The cigarette as claimed in claim 26, wherein said tubular body has a smaller inside diameter than said free flow filter.
Parent Case Info

This application claims priority under 35 U.S.C. §119 to Provisional Application No. 60/191,455 filed in the U.S. on Mar. 23, 2000; Provisional Application No. 60/191,460 filed in the U.S. on Mar. 23, 2000; and Provisional Application No. 60/191,461 filed in the U.S. on Mar. 23, 2000; the entire contents of which are hereby incorporated by reference.

US Referenced Citations (18)
Number Name Date Kind
3496945 Tomkin Feb 1970 A
3637447 Berger et al. Jan 1972 A
5060671 Counts et al. Oct 1991 A
5144962 Counts et al. Sep 1992 A
5372148 McCafferty et al. Dec 1994 A
5388594 Counts et al. Feb 1995 A
5498855 Deevi et al. Mar 1996 A
5499636 Baggett, Jr. et al. Mar 1996 A
5505214 Collins et al. Apr 1996 A
5591368 Fleischhauer et al. Jan 1997 A
5665262 Hajaligol et al. Sep 1997 A
5666976 Adams et al. Sep 1997 A
5692291 Deevi et al. Dec 1997 A
5692525 Counts et al. Dec 1997 A
5865185 Collins et al. Feb 1999 A
5902501 Nunnally et al. May 1999 A
5954979 Counts et al. Sep 1999 A
6040560 Fleischhauer et al. Mar 2000 A
Non-Patent Literature Citations (2)
Entry
Notification of Transmittal of International Preliminary Examination Report for PCT/US01/09302, dated Aug. 29, 2002.
Written Opinion dated Mar. 25, 2002 for International Application No. PCT/US01/09302.
Provisional Applications (3)
Number Date Country
60/191455 Mar 2000 US
60/191460 Mar 2000 US
60/191461 Mar 2000 US