US2890703A - Cigarette construction - Google Patents

Description

June 16, 1959 H. B. GROW 2,890,703

I CIGARETTE CONSTRUCTION Filed Sept. 29, 1954 IN V EN TOR. /70//0W 5. 6/0/44 5 wwlmu 2,890,703 Ice Patented June 16, 1959 CIGARETTE CONSTRUCTION Harlow B. Grow, Pacific Palisades, Calif.

Application September 29, 1954, Serial No. 459,153

Claims. (Cl. 131-10) This invention relates to a cigarette construction which results in a tasteful satisfying smoke comparatively free of harmful components.

It is known that cigarette smoking is injurious to the health of the smoker because of the many irritants contained in the smoke. Consequently various types of filters have been incorporated into the structure of a cigarette, or in the holders therefor, in an attempt to remove the irritants. However, such filters are not effective or they alter the smoke of a cigarette to the extent that smokers find the smoke tasteless and unsatisfactory.

It is believed that the irritants in cigarette smoking are formed under low burning conditions when the burning temperature is low and there is lack of suificient air to support optimum combustion. On the other hand, if optimum combustion could be maintained the irritants would be greatly reduced. It is obvious that optimum conditions cannot be maintained because of the idle periods between draws that occur during the leisurely smoking of a cigarette. During these idle periods, the temperature is low with the result that irritating tars, oils and vapors are generated in the slow burning tobacco. Then during the initial draw on the cigarette these irritants are carried with the smoke into the mouth of the smoker until the temperature and air flow is sufiicient to obtain optimum combustion and a material reduction of the irritants. Thus during each draw on the cigarette, the initial portion is harmful but the remaining portion is less harmful and more tasteful.

With this in mind, it is the principal object of the present invention to provide a cigarette structure whereby the irritants are filtered out of the smoke during the initial portion of the draw on the cigarette and during the remaining portion of the draw, the smoke by-passes the filter media. In this manner, the irritants which have been generated during the low burning period are removed by the filtering media and the by-passed smoke which is substantially free of injurious factors, passes directly into the mouth of the smoker and is not contaminated by passage through the filter.

Other objects of the invention are to provide a cigarette structure having a selective filter of simple and inexpensive construction; and to provide a filter element having one or more valved passages forming a part thereof and operable responsive to the pressure differential established at the respective ends of the filter element.

In accomplishing these and other'objects of the invention hereinafter pointed out, I have provided improved structure the preferred forms of which are illustrated in the accompanying drawings wherein:

Fig. 1 is an enlarged longitudinal section through a cigarette constructed in accordance with the present invention, the section being taken on the line 11 of Fig. 2, to show the filtering elements and the passageways therebetween, with the passageways being closed by tions of the filtering elements.

Fig. 2 is an end view of the filter end of the cigarette.

Fig. 3 is a longitudinal section similar to Fig. 1 but showing the passageways open for by-passing the smoke.

Fig. 4 is an end View showing the opened passageways.

Fig. 5 is a graph showing the temperature values along the length of a lighted cigarette during-an idle period in the smoking thereof.

Fig. 6 is a similar graphic representation but showing the temperature values when the draft and temperature is increased.

Fig. 7 is a longitudinal section through the filter end portion of a modified form of construction and showing the filtering element in position for removing irritants from the smoke.

Fig. 8 is an end view of the form of invention shown in Fig. 7.

Fig. 9 is a section similar to Fig. 7 and showing the filter element in position for by-passing the smoke.

Fig. 10 is an end view of the cigarette, showing the by-pass open.

Fig. 11 is an end view of a further modified form of the invention.

Fig. 12 is a fragmentary sectional view of the form of invention illustrated in Fig. 11 and showing the bypass with the valving element therefor in closed position.

Fig. 13 is a section similar to Fig. 12 but showing the valving element in open position.

Referring more in detail to the drawings and first to the form of invention illustrated in Figs. 1 to 4 inclusive:

1 designates a lighted cigarette including a cylinder of finely shredded tobacco 2 contained in a wrapper 3. And inset at one end is a filter 4 constructed in accord ance with the present invention. The drawing shows the cigarette lighted as indicated by a fire area 5 and an ash area 6. Fig. 5 depicts the temperature values along the length of the cigarette l and while the cigarette is smoldering between periods of active draft through the tobacco. The horizontal line 8 in Fig. 5 representsa base or external temperature, the line 9, the temperature of the ash 6 and the lines 10 and 11 converging in the peak 12 indicate the temperature of the burning tobacco 5 while the line 13 indicates the temperature on the tobacco side of the fire. It will be noted tempera ture rises from the ash temperature to a maximum value in the fire area and the temperature decreases over the. distance indicated at A when no air is being drawn through the cigarette indicating that the burning rate is relatively slow. On the other hand, when air is drawn through the cigarette the temperature rise from the line 9' as represented by the line W in Fig. 6, is substan tially higher and a higher peak 12 is reached and the. temperature drop therefrom, as represented by the line 11, is over a much shorter period B.

The speed of combustion indicated B in Fig. 6,- being quite short, eliminates many of the irritants generated during the slow burning time A, and the smoke produced during the shorter burning time is relatively free of irritants. However, this smoke will pick up and carry with it the irritants that have been formed during the slow burning period.

When ordinary filters are used to filter out the irritants generated during time A, they also contaminate the smoke that is generated during burning time B so that the net result of filtering is substantially nullified. The present invention avoids this difficulty and providesai satisfactory smoke by providing the cigarette with a novel filter 4. The filter 4 of the present invention is arranged to filter the smoke which results from the burning tifiie A during the initial draw on the cigarette andto h y pass the smoke generated during, the burningtime Bff The form of invention shown in Fig. 1 includes a disk- A m: m

support 14 having a series of openings or pockets 15 in which are mounted filter elements 16 with the areas intermediate the openings 15 being provided with perforations or pores 17 through which the smoke is drawn. Each filter element 16 is tubular and may comprise one 'or more layers of filter material such as a filter paper or the like. The filter element 16 that is illustrated in Figs. 1, 3, 7 and 9 is of substantially cone-shape whereby the walls 18 flare outwardly providing filter areas closing the outer ends of passageways therebetween. It will be noted that the filter elements 16 are supported in a regular and orderly manner in side to side relation, with the apical ends spaced apart and carried by the support through the passageways of the outer sides of the cones 14, with the base portions extending toward the mouth of the smoker, consequently, definite filter areas and passageways 20 are provided. It is also obvious that the apical ends are closed as at 18 to cooperate with the walls 18 in providing inner suction chambers 16" open through the base portions 19 of the elements to the mouth of the smoker. The filter elements have sufficient inherent resiliency so that the base portions 19 of the filter elements are normally in yieldable contact with each other to provide valve means adapted to open when the draft becomes sufficient. With this arrangement the initial flow of air and smoke is through the filter media, until the pressure acting on the exterior walls of the filter elements effects contraction of the base portions thereof, as shown in Figs. 3 and -4, to open the passageways 20 and allow direct passage of the smoke into the mouth of the smoker. When the pressure differential again drops, the inherent resiliency of the filter elements causes the base portions 19 to again close the passageways 20.

In the form of the invention illustrated in Figs. 7, 8, 9, and 10, the filter 21 includes a capsule-like support 22 that is formed of porous material and which provides an enclosure for a similarly shaped filter element 23 that is contained therein. The support has an annular wall 24 which fits within the cigarette wrapper and a rounded end 25 which extends across the tobacco compartment of the cigarette. The filter element has a similar annular wall 26 and end 27 normally contacting the corresponding portions of the support. The wall portion 26 of the filter element is resistant to the initial pressure to cause the initial flow of smoke through the filtering material but as the pressure differential increases, the Wall portion 26 contracts under the increased pressure and moves inwardly from the support to provide an open annular passageway 28 for the smoke, as shown in Figs. 9 and 10.

The form of invention shown in Fig. 11 includes a cylindrical filter 29 having a passageway 30 therethrough and which is normally closed by a valve 31. The valve 31 may be formed of resilient material and has a relatively narrow tongue portion 32 that is attached to the outer periphery of the filter and has a flap 33 suitably connected therewith as indicated at 34 to cover the mouth end of the passageway 30. Under normal conditions occurring as represented by the diagram Fig. 5, the flap 33 closes the passageway 30 so that during the initial draw, the smoke which carrys the harmful components is caused to pass endwise through the wall of the filter and around the closed flap, but as the pressure differential increases, the flap 33 opens to allow direct flow of smoke through the passageway 30.

When a cigarette constructed in accordance with any one of the various forms of the invention has been lighted and the tobacco is burning under the conditions depicted by the graph Fig. 5, the valve means of the filter is closed because there is no air being drawn through the cigarette. Under this condition, the tobacco burns with very little air and the burning rate is slow as represented by A. Consequently, the combustion is poor and harmful prodnets are formed, but when the smoker begins to draw upon the cigarette, the suction establishes an initial low 4 pressure within the cones, but the initial pressure differential on the respective sides of the wall portions of the filters is not sufficient to open the valve means with the result that the initial smoke, heavy with tars and other harmful products, is drawn through the filtering media. The filtering media therefore eliminates the harmful components that have been formed under the poor burning conditions. Continuation of the draw on the cigarette results in a future pressure drop within the cones and an increased air supply to promote combustion of the tobacco to the point where the harmful components are not formed. Consequently the smoke now formed being free of harmful components is by-passed directly to the mouth of the smoker as soon as the pressure differential becomes high enough to open the valve means. This smoke being unfiltered provides the desired tasts and gives a satisfactory smoke without the hazards which result by the use of conventional cigarettes.

From the foregoing it is obvious that I have provided a cigarette structure wherein the filter element acts to filter the portion of the smoke containing the harmful components and has by-pass means to by-pass the smoke when the smoke is comparatively free of the harmful components.

It is also obvious that the filter element when used between the tobacco and the mouth of the smoker provides a generally elongated body of filtering media for filtering the smoke under low draft conditions when the tobacco of smoke through the filter media and by the yielding of the valving part or parts from closed position under an increase in draft to open the passage to direct flow of unfiltered smoke.

What I claim and desire to secure by Letters Patent is:

l. A cigarette including a generally cylindrical wrapper and tobacco contained in the wrapper, a filter in one end of the wrapper and in the path of the smoke when the cigarette is in use, said filter including a support having openings and having perforated areas between said openings for passing smoke, and substantially cone-shaped filter elements having apical portions mounted in said openings and having base portions in contact with each other and with the wrapper to close passageways between said filter elements and said base portions being yieldable responsive to the volume of air drawn through the cigarette for establishing flow through said passageways.

2. A filter for a cigarette including a generally cylindrical body composed of a plurality of hollow cones having wall portions formed of a filtering media, and adapted for use between the tobacco of the cigarette and the mouth of a smoker, for filtering smoke under low draft conditions when the tobacco of the cigarette burns responsive to a limited air supply, said cones being arranged in a bundle with the apical ends at the tobacco end of said body and spaced apart to form passages therebetween and with base portions thereof in yielding contact with each other for closing said passages under low draft conditions whereby the smoke is diverted through the walls of said cones to remove harmful components of the smoke resulting from slow burning of tobacco under the low air supply and said contacting portions being yieldable from said closing position under an increase in the draft to open the passages to direct flow of unfiltered smoke.

3. A filter adapted for insertion between the tobacco of a cigarette and the mouth of a smoker, said filter including a plurality of tubular members having wall portions formed of filtering material and each having one end closed and the other end open, means for supporting said tubular members with the closed ends thereof in the direction of the tobacco and in side to side spaced apart relation to provide outer passageways therebetween and with the open ends toward the mouth and in substantial contact with each other for providing valving means closing 01f the outer passageways to the mouth of the smoker, said tubular members providing interior chambers open to the mouth of the smoker for establishing initial low pressure within the chambers responsive to suction from the mouth of the smoker to first efiect flow of smoke from the outer passageways through wall portions of the cones into said chambers and through said open ends into the mouth of the smoker under slow burning of the tobacco, said wall portions at the open ends being resilient and yieldable inwardly upon further drop in pressure within said chambers to open the exterior passageways directly to the mouth of the smoker for passing unfiltered smoke to the mouth of the smoker under increased burning of the tobacco.

4. A filter adapted for insertion between the tobacco of a cigarette and the mouth of a smoker, said filter including a plurality of hollow cones having wall portions formed of filtering material, means for supporting said cones with apex ends thereof in the direction of the tobacco and in side to side spaced apart relation to provide outer passageways therebetween and with the base portions toward the mouth and in substantial contact with each other for providing valving means closing 011 the outer passageways to the mouth of the smoker, said cones providing interior chambers having openings through the bases of the cones to the mouth of the smoker for establishing initial low pressure within the chambers responsive to suction from the mouth of the smoker to first effect flow of smoke from the outer passageways through the wall portions of the cones into said chambers and through said open bases into the mouth of the smoker under slow burning of the tobacco, said base portions of the cones being resilient and yieldable inwardly under further drop in pressure within said chambers to open the exterior passageways directly to the mouth of the smoker for passing unfiltered smoke to the mouth of the smoker under increased burning of the tobacco.

5. A cigarette including a generally cylindrical wrapper and tobacco contained in the wrapper, a filter in one end of the wrapper and in the path of the smoke when the cigarette is in use, said filter including a porous support encircled by the wrapper of the cigarette and being porous for passing the smoke therethrough, and substantially cone-shaped filter elements having apical portions carried by the support and having base portions in contact with each other and with a part of the wrapper to close passageways between the filter elements, and said base por-' tions being yieldable responsive to the volume of air drawn through the cigarette for establishing flow through said passages.

References Cited in the file of this patent UNITED STATES PATENTS 973,890 Surburg Oct. 25, 1910 1,338,529 Richter Apr. 27, 1920 1,500,802 Chantilis July 8, 1924 1,557,351 Fisher Oct. 13, 1925 2,039,298 Davidson May 5, 1936 2,064,239 Aivaz Dec. 15, 1936 2,164,702 Davidson July 4, 1939 2,171,770 Strauch Sept. 5, 1939 2,222,948 Hellfritzsch Nov. 26, 1940 2,511,898 Brothers June 20, 1950 2,597,124 Nohr May 20, 1952 FOREIGN PATENTS 60,967 Germany Mar. 3, 1892

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