US2954780A

US2954780A - Device for removal of tar and other deleterious substances from tobacco smoke

Info

Publication number: US2954780A
Application number: US704422A
Authority: US
Inventors: Herbert A Lebert
Original assignee: Mac Farland Aveyard & Co
Current assignee: Mac Farland Aveyard & Co; Mac-Farland Aveyard & Co
Priority date: 1957-12-23
Filing date: 1957-12-23
Publication date: 1960-10-04
Anticipated expiration: 1977-10-04

Description

Oct. 4, 1960 H. A. LEBERT 2,954,780

. DEVICE FOR REMOVAL OF TAR AND OTHER DELETERIOUS SUBSTANCES FRQM TOBACCO, SMOKE Filed Dec. 23, 1957 H, x IIIIIIIIllIIIIIlIIII/lllllV 1 infa Patented Oct. 4, 1960 DEVICE FOR REMOVAL OF TAR AND OTHER gE-LETERIOUS SUBSTANCES FROM TOBACCO MOKE Herbert A. Lebert, MillbraegCalifi, assignor to Mac- Farland, Aveyard & Company, Chicago, 111., a corporation of Delaware FiledDec. 23, 1957, Ser. No. 704,422 2 Claims. (Cl. 131-187) This invention relates to the removal of tar and other deleterious substances from tobacco smoke and particularly to an orifice and impingement barrier combination for the removal of tars, resins, and other harmful substances in the smoke. In the following description, such harmful substances will be referred to for convenience as tars.

In the past, many devices have been proposed for the treatment of tobacco smoke and for the elimination of portions or fractions of component parts of the smoke therefrom. The removal of tars has posed a serious problem because of their known harmful effects to health. Screens and orifice-equipped disks have been proposed, the effective opening for the flow of smoke being quite minute, but while some tar is removed in the operation of such devices, a satisfying flow of smoke is not obtained. Furthermore, a sufficient proportion of the tars are not removed.

The present structure or tar filter device fundamentally differs from previous types of tar filter devices by obtaining tar separation by means of providing a structure adapted to cause tar separation by impingement of high velocity tar ladened smoke against an impingement barrier. Tests tend to indicate the present new technique is far more effective than any previously known tar filtering device in effectively removing tars and especially the more dangerous high temperature tars from tobacco smoke while at the same time enabling the smoker to obtain a pleasurable smoke without a hard draw.

The results of research by independent experts in this field tend to indicate that the tars extracted from the lower temperature-burning ranges (560 to 720 C.) produce few or no cancers. The number of cancers increased sharply through the use of tar taken from tobacco burning from the higher temperature ranges (720 to 880 C.). Tests have also shown that a cigarette burns between 800 to 880 C. so that the more dangerous high temperature tars are presently being inhaled by the cigarette smokers. (See Time magazine, April 22, 1957, page 50.)

Early experiments indicate that where the velocity eX- pansion cooling principle is used to obtain tar separation, a relatively low percentage of the high temperature tars are separated out of the smoke as opposed to the use of the instant relationship involving high velocity tobacco smoke impingement without expansion wherein a relatively high percentage of high temperature tars are separated.

In the application of this new technique, manufacturing advantages are present since structures of this type are far more compact than those using the velocity-expansion principle where a relatively large chamber is required for condensing the smoke. 7

It has been found that there is a practical dimensional range with regard to the size of the orifice and its distance from the barrier.

.If the orifice is too small the smoker is inconvenienced through his difiiculty in drawing the smoke through the device, and if the orifice is too large, the velocity of the smoke passing through the device is reduced in a manner whereby the percentage of tar separation is materially reduced. If the gap between the orifice and the barrier is too great or too small the A, percentage of tar separation or the rate of tar flow is adversely effected. In this respect, the impingement barrier is almost in contact with the orifice with there being just enough clearance to allow the formed relatively viscous tar to flow out of the path of the tar subsequently 3 formed. There is no expansion space or condensing surface as in the above patents required here for tar separation from the smoke.

By using an orifice with a .028" to .030 diameter and a distance between the impingement barrier and the orifice of to 1 the best results are obtainable. In other words, by constructing a device incorporating the above dimensional range, the smoker may have a more pleasurable easy draw smoke with the high percentage removal of the tars including the more dangerous high temperature tar. Early tests of structures utilizing this principle tend to indicate that at least 40% of the tars may be removed. This 40% represents almost of the high temperature formed tars while the low temperature aromatic fractions of smoke are passed on to the smoker.

Accordingly, a very important object of the present invention is to provide means for the tar removal fromtobacco smoke through the use of an impingement barrier employed at a spaced and effective distance from a Venturi orifice or a small orifice which causes the smoke to flow at a sufiicient velocity to cause separation of the tar as the smoke strikes the impingement barrier.

Another object of this invention is to provide a multipart cigarette structure having novel means for separating tars including a high percentage of high temperature tars from tobacco smoke While at the same time allowing the smoke to be drawn through the cigarette holder without great difficulty enabling a smoker to obtain a pleasurable smoke without the danger attendant with the drawing of the high temperature tars into the body and lungs of the smoker.

Another object of this invention is to provide a multipart cigarette holder structure which is easy to clean by readily separating the parts, and which structure may be manufactured on a large production basis at an economical cost.

A further object of this invention is to provide a thermoplastic holder having new and improved structure for separating tars from tobacco smoke which insert is adapted for use in a tobacco burning smoking structure.

Yet another object of the present invention is to provide a highly compact structure for separating the tar from tobacco smoke.

Other objects and features of the present invention will more fully become apparent in View of the following detailed description taken in conjunction with the accompanying drawings illustrating therein a single embodiment, and in which:

Figure 1 is a top plan view of a multi-part cigarette holder structure carrying a cigarette and which holder structure has tar separation structure according to the principles of the present invention.

Figure 2 is an enlarged exploded view of the multi part cigarette holder structure shown in Figure 1;

Figure 3 is an enlarged fragmentary cross-sectional view taken substantially along the line IIIIII on Fig ure 1 looking into the direction indicated by the arrows;

Figure 4 is an enlarged fragmentary cross-sectional view of a portion of the structure shown in Figure 3;

and

suitable materials although I have found that excellent, results may be attained through the manufacture. of'the,

mouthpiece 12 from a suitable plastic, such as thermoplastic, a suitable composition, or any suitable material.

The outer sleeve or tube 13 may be manufactured. from,-

metal or plastics, or from any suitable material.

The mouthpiece 12 has an. enlarged or transversely elongated downstream end 14 and a reduced diameteredupstream end portion 15 with an axiallyv or longitudinally upstream facing shoulder 16 disposed at the junction of the reduced end portion 15 with the full diameter body portion of the mouthpiece 12. The reduced end, portion 15 most suitably has a circular peripheral surface 15a having a diameter corresponding to the outside diameter of peripheral surface 11a of the cigarette. Thetubular sleeve 13 most suitably has an internal circular surface 13a having a diameter very slightly at variance with the diameters of the peripheral surfaces 11a and 15a of thev cigarette 11 and the reduced end portion 15. Thus when. the components are assembled, the sleeve has an. annular shoulder 13b abutted against the annular shonld'er'16 of the mouthpiece and the internal surface 13a is frictionally engaged with the peripheral surface 15a of the reduced end 15. The sleeve 13 has a free cigarette-receiving socket end portion projecting beyond a blunt forwardly facing stop end 15b of the mouthpiece and is flared at 130 at the tip end of the socket to aid in telescoping the butt end of the cigarette 11 inside of the sleeve socket in frictional engagement therewith and with the cigarette abutted against the circular longitudinally forwardly facing shoulder 15b.

The mouthpiece 12 includes a main longitudinally extending passageway 12a which extends into and internally of the reduced end 15 whereupon the main passageway is linked to a radial passageway 15c.

Extended along the length of the reduced end in longitudinally or axially spaced relation is a series of annular or circular grooves or passageways 15d which are separated by annular lands or partitions 152 and linked together by single reduced cross-sectional flow area longitudinal or axial grooves or passages 8 respectively extending through the peripheries of the partitions 15a and which passages. 18 are alternated in approximately 180 relation to one another. The grooves 15d. and 18 are both semi-circular in cross section and opening outwardly from the periphery of the mouthpiece reduced diameter portion 15 for easy cleaning.

Disposed radially of the area of the shoulder 15b. the reduced end portion 15 is formed with a rabbet groove prow'ding an annular stepped shoulder area 15 f defining a smoke collection recessarea about the stop shoulder 15b. The stepped groove 15 thecigarette 11 and the sleeve surface 13a cooperate together to define a smoke collection chamber 1'7. The reduced flow area passages. 18 define discharge orifices of predetermined cross-sectional fiow'area or diameter. The annular grooves 15d have wallareas longitudinally or axially opposite the orifices 18 defining impingement barriers 19 so that the smoke mayv passthrough the-orifices 18 at highvelocitytoimpinge tar T from the smoke upon the collision of the smokeagainst. the barrier 19 in each instance.

As heretofore stated, the problem presented has beenone. of. providing. sufficient. smoke flow to satisfy the smoker, while at the same time removing the deleterious tars,,etc.. In. the structure of the present invention, this result is achieved by employing an impingement barrier in combinationwith an orifice which greatly increases the velocity of'the smoke stream so-that when the stream strikes the barrier, the tar is lodged and collected upon the surface of the barrier 19 and in the chamber respectively providing by each of the grooves 15d and the resulting purified smoke alters its course through the passageway 15c and passes on to the smoker through the mouthpiece. While there will be variations in the size of the orifice, and in the spacing of the barrier from the outlet of the orifice, depending upon' the character of the smoke, the density of the cigarette mass, etc., I find that in general efiective results are obtained where the orifice diameter isfrom .025" to .038 (square inch area of .0005 to .001). Very satisfactory results have been obtained 1 where the orifice diameter is .028 to .032 (.0006 to .0008

square inch)". As a preferred example, I have employed effectively an orifice havinga diameter of 0.030 (.0007 square inch), which gives excellent tar removal and ease of drawing. I

The critical orifice size is correlated. with the impingement barrier which is located as close as possible to the orifice or Venturi outlet consistent with the free flowing of the collected tars; e.g., without impairing the flowing of the tar away from the point of impingement. In practice, I have found that a satisfactory range is a distance of 3 to of an inch, or about .03 to .187 of an inch. A still more satisfactory range lies between to of an inch. A preferred distance is .030 of an inch. In the specific example referred to, the barrier is spaced from the orifice outlet by of an inch (.030 of an inch), or approximately the orifice diameter.

The operation resulting from the structure shown here in is in contrast to the operation of cooling devices heretofore employed with cigarettes. Such cooling devices bring about a peripheral cooling of the smoke but allow substantial core portions of the tars to pass on to the smoker. In my structure, the entire cross section of the smoke strearn is subject to the action of the impingement barrier so that the tars and other harmful particles are removed by the foregoing high velocity impingement action upon the barrier.

The barrier is presently illustrated as a solid barrier. The slight spacing between the outlet of the orifice and the barrier enables the smoke stream to reach the barrier with substantially undiminished speed, while at the same time enabling the purified smoke to change direction whereas tar fractions, by reason of their high inertia, can not change direction and therefore deposit on the first surface contacted.

The passage or orifice is effective in greatly increasingthe velocity of the smoke so that it is substantially in excess of feet per second. Of course, the velocity will vary considerably with different smokers and with cigarettes of varying degrees of density. By spacing the barrier close to the outlet of the orifice, the attained high velocity is effective in lodging the tar fractions directly upon the barrier wall where an impervious barrier is employed, and further, such high velocity is effective, in the case of the solid barrier wall, in moving the viscous tar along the barrier face to an unobstructing position in the sump or reservoir space. The space between orifice outlet and impingement barrier may be from 0.01 to 0.187". In the preferred structure, the spacing is about 0.30.

In operation, upon the smoker applying a suction force on the enlarged end 14, smoke is drawn through the ignited cigarette into the smoke collection chamber 17 and then into thefirst orifice passage 18 in the series. A high velocity smoke stream is formed 'as the smoke is drawn through the orifice 18, and the smoke stream is impinged against the barrier 19 leaving the tars T. The smoke stream is deflected in opposite directions away from the barrier 19 dividing the stream into sub-streams which are flowed in semi-circles and are merged at the next' orifice 18 in the series which is circumferentially spaced from the first-in-the-series orifice 18 approximately on the opposite side of the reduced end' portion 15 so that tars collected at the barrier will not interfere with the passage of the smoke through the second reduced orifice passageway 18. The smoke stream then passes through the second orifice 18 and is directed at high velocity against the barrier 19 confronting it and more tars are separated from the smoke with the stream again being divided into sub-streams and then collected and passed through a third reduced orifice passageway 18 against a third barrier 19 downstream therefrom. The smoke after striking the last barrier, and any suitable number of barriers may be employed, is then deflected into the radial passage 15c and out through the main passage 12a into the smokers mouth.

The passageways 15d and 18 are preferably semicircular and disposed at the periphery of the reduced end portion 15 since upon pulling the sleeve and removing it from the reduced end, a cloth may be used to wipe the tar out of the grooves. The grooves are separated by the dividing lands 15e whose peripheral portions of the surface 15a form a substantially air tight fit with the sleeve 13.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention.

I claim as my invention:

.1. In a device for removal of tar and other deleterious substances from tobacco smoke, a mouthpiece having a forward end portion, a sleeve removably engaging encompassingly about said end portion and projecting forwardly therefrom and providing a socket receptive therein of the butt end portion of a smokable article, the forward article opposing end of said end portion having a smoke collecting recess therein, the periphery of said end portion having a plurality of annular grooves therein spaced from one another by a partition land respectively therebetween, a single longitudinally extending peripheral orifice groove in said end portion connecting said collection recess with one of said annular grooves which is nearest said end and a single longitudinal orifice groove in the periphery of the land partition separating said one annular groove from the next and adjacent annular groove thereto and ofiset circumferentially a substantial distance relative to the first mentioned orifice groove, said mouthpiece having a rearwardly opening passageway therein extending forwardly short of said forward end and communicating with said next adjacent annular groove, each of said orifice grooves having an orifice cross-sectional flow area of .0005 to .001 square inch whereby to effect acceleration of smoke downstream therefrom at a velocity in excess of 100 feet per second and the respective annular grooves into which the orifice grooves discharge presenting impingement barriers confronting the downstream ends of the orifice grooves at a distance of .01 to .187 inch so that smoke issuing from each of the orifice grooves successively will impinge the respective barrier and d posit tars t ere n and move laterally in the respective annular groove to continue downstream until the smoke passes out through said passageway, said sleeve providing a circumferential closure for all of said grooves and maintaining said recess and said annular grooves in substantially airtight separation so that communication therebetween is limited to said orifice grooves, said annular grooves and said orifice grooves being of smoothly rounded cross-section to facilitate cleaning thereof when said sleeve is removed from said end portion to expose the grooves.

2. In a device for removal of tar and other deleterious substances from tobacco smoke, an elongated mouthpiece having a generally cylindrical forward end portion, a sleeve removably encompassingly engaging said end portion and projecting therebeyond and providing a socket receptive of a smokable article therein, said end portion having a forward end smoke-collecting recess therein, an annular groove in the periphery of said end portion adjacent to said forward end but spaced from and closed 011 from said recess by an intervening portion of said end portion and circumferentially closed by said sleeve, a single longitudinal peripheral orifice groove in said intervening end portion connecting said recess and said annular groove and providing a smoke stream accelerating orifice of a size of about .0005 to .001 square inch cross-sectional flow area, said groove providing an impingement barrier confronting said orifice in a spaced relation of about .01 to .187 inch, the mouthpiece having a rearwardly opening longitudinal smoke passageway therein extending short of said forward end, the forward end portion of said passageway communicating with said groove at a point ofiset peripherally from said orifice groove whereby smoke issuing at high speed from said orifice impinges said barrier and then travels laterally in said annular groove and passes on into said passageway, said annular groove and said orifice groove being of rounded cross-section for ease in cleaning when the sleeve is removed from said end portion.

References Cited in the file of this patent UNITED STATES PATENTS 256,033 Naughten Apr. 4, 1882 708,404 Remore Sept. 2, 1902 925,381 Regenold June 15, 1909 2,024,865 McArdle Dec. 17, 1935 2,202,288 Heron May 28, 1940 2,385,651 Ricketts Sept. '25, 1945 2,511,898 Brothers June 20, 1950 2,764,513 Brothers Sept. 25, 1956 FOREIGN PATENTS 146 Great Britain 1880 155,189 Great Britain Dec. 16, 1920 341,552 France June 13, 1904 760,772 Great Britain Nov. 7, 1956