SMOKING ARTICLES
United States Patent 3630210
A smoking article or attachment is provided with means by which a puff is divided automatically into a first portion and at least one later portion and the smoke portions produced are differentially and/or separately filtered. The puff-dividing means may be a valve device subject to the suction produced by the puff and arranged to control the opening of a smoke passage additional to a constantly open smoke passage. The constantly open passage opens into a high-density filter region and the additional passage into a lower-density filter region.
US Patent References:
Cigarette holder
Allen - June 1925 - 1543043
Pipe adapter
Davis - September 1958 - 2850021
Cigarette construction
Grow - June 1959 - 2890703
Smoker's mouthpiece
Huber - October 1967 - 3348553
SMOKERS' SMOKE TREATMENT ATTACHMENT
Bennett et al. - August 1969 - 3463166
Cigarette holder
Allen - June 1925 - 1543043
Pipe adapter
Davis - September 1958 - 2850021
Cigarette construction
Grow - June 1959 - 2890703
Smoker's mouthpiece
Huber - October 1967 - 3348553
SMOKERS' SMOKE TREATMENT ATTACHMENT
Bennett et al. - August 1969 - 3463166
Application Number:
04/859388
Publication Date:
12/28/1971
Filing Date:
09/19/1969
View Patent Images:
Export Citation:
Assignee:
Brown and Willamson Tobacco Corporation (Louisville, KY)
Primary Class:
Other Classes:
131/215.300, 131/339, 131/215.200
International Classes:
A24D3/04; A24D3/00
Field of Search:
131/10.5,10.3,10.7,215,215A,215B,261B,261,223
Primary Examiner:
Koren, Samuel
Assistant Examiner:
Pitrelli J. F.
Claims:
I claim
1. A filter device adapted to be inserted between the tobacco of a smoking article and the mouth of a smoker for automatically dividing a puff into a first portion and at least one later portion and differentially and separately filtering each portion comprising a filter section having first and second filter regions and a valve section positioned between the said filter section and the tobacco, said valve section including a constantly open smoke passage to the first filter region and an additional passage to the second filter region, said additional passage embodying a spring-loaded valve subject to the suction produced by the puff and positioned to control the opening of the additional passage.
2. The filter device of claim 1 in which the first filter region is of high density and the second filter region is of lower density.
3. The filter device of claim 1 in which the additional passage embodying the valve is provided with axially spaced radial ports leading to a substantially annular passage bypassing the valve.
1. A filter device adapted to be inserted between the tobacco of a smoking article and the mouth of a smoker for automatically dividing a puff into a first portion and at least one later portion and differentially and separately filtering each portion comprising a filter section having first and second filter regions and a valve section positioned between the said filter section and the tobacco, said valve section including a constantly open smoke passage to the first filter region and an additional passage to the second filter region, said additional passage embodying a spring-loaded valve subject to the suction produced by the puff and positioned to control the opening of the additional passage.
2. The filter device of claim 1 in which the first filter region is of high density and the second filter region is of lower density.
3. The filter device of claim 1 in which the additional passage embodying the valve is provided with axially spaced radial ports leading to a substantially annular passage bypassing the valve.
Description:
This invention concerns improvements relating to smoking articles, especially but not exclusively cigarettes.
It is known from experimental work using automatic smoking engines that the composition of the tobacco smoke from smoking articles can be altered by changes in puff volume, puff frequency and the velocity of the airstream during puffing. Consideration of the results obtained from such experiments suggests that the concentration of the more involatile, less desirable, compounds occurring in tobacco smoke is higher in the first portion of the puff than in the later part.
According to the invention, a smoking article is provided with means by which a puff is divided automatically into a first portion and at least one later portion and the smoke portions produced are differentially filtered.
Also according to the invention, a device adapted for attachment to a conventional smoking article comprises means for dividing a puff of smoke automatically into a first portion and at least one later portion and filter means arranged to filter the smoke portions produced differentially.
Suitably, the first smoke portion of the puff comprises the portion delivered during the first quarter to the first half of the duration of the puff.
Two embodiments of the invention, as applied to cigarettes, will now be more fully described by way of example and with reference to the accompanying drawings, in which:
FIGS. 1 and 2 are diagrammatic longitudinal sections through the said embodiments, and
FIG. 3 is a diagram in which pressure drop is plotted against time.
Referring to FIG. 1, the complete smoking article shown comprises a tobacco-containing section 1, a valve section 2 and a filter section 3. The section 1 may be of the nature of a conventional cigarette with tobacco 4 contained in a paper wrapping 5. The section 2 comprises a short cylinder 6 of cigarette diameter made of metal or a plastics material and attached in abutting relation to the section 1 by an adhesive band 7. A substantially complete narrow annular passage 8 or ring of narrow passages through the cylinder 6 near its periphery allows free flow of smoke during puffing. A larger axial passage 9 through the cylinder 6 is connected by axially spaced radial ports 10, 11 to a further substantially annular passage 12 extending for a substantial distance, but not completely through, the length of the cylinder. The axial passage 9 is normally obturated at the end adjacent to the section 1 by a resiliently loaded valve body. In the example, the valve body comprises a ball or spherical plug 13 retained in the obturating position illustrated, i.e. upstream of the radial ports 10, by a light helical compression spring 14 disposed in the axial passage 9. The filter section 3 secured in abutting relation to the section 2 by an adhesive band 15 comprises conventional fibrous or sheet tobacco-smoke-filtering material in a wrapper 16. At least the peripheral region 17 of the filter adjacent to the exit orifice of the annular passage 8 is of higher density, or has higher smoke-retention properties, than the inner or axial region 18, from which it is separated by a cylindrical paper sleeve 17'. A higher pressure drop is produced in the region 17 than in the region 18.
In use, when initial suction is applied to the smoking article through the section 3, smoke is drawn only through the narrow passage 8, the valve body 13 remaining in the obturating position. This initial portion of the puff passing through the passage 8 is filtered by the high-density filter region 17. As suction continues to be applied, the valve body 13 is retracted just pass the radial ports 10 and, while still closing the axial passage 9 for the middle portion of its length, permits smoke from the section 1 to pass into the annular passage 12 and so, via the ports 11, to the lower density filter region 18. The smoke path through the passage 8 and filter region 17 is thus bypassed to an extent which can be predetermined by design.
With such a device, the smoke produced during the earlier part of the puff is more strongly filtered, at 17, than the smoke of the later part of the puff, at 18, whereby more efficient filtration and a more desirable composition of the smoke entering the smoker's mouth can be ensured.
The smoking article of FIG. 2 differs from that of FIG. 1 in that the lower density inner filter region 18a is enclosed to the rear, as well as circumferentially, by the higher density filter material of the region 17a. A similar differential filtration effect is obtained.
FIG. 3 in which the pressure drop PD in smoking article in accordance with the invention is plotted against time T, illustrates, in general profile only, an example of a two-portion puff comprising a brief, initial, high peak 19 followed by a maintained lower value 20 of the pressure drop. The diagram is not dimensional, but the whole puff may, for the sake of example, be assumed to have a duration of about 2 seconds.
It is known from experimental work using automatic smoking engines that the composition of the tobacco smoke from smoking articles can be altered by changes in puff volume, puff frequency and the velocity of the airstream during puffing. Consideration of the results obtained from such experiments suggests that the concentration of the more involatile, less desirable, compounds occurring in tobacco smoke is higher in the first portion of the puff than in the later part.
According to the invention, a smoking article is provided with means by which a puff is divided automatically into a first portion and at least one later portion and the smoke portions produced are differentially filtered.
Also according to the invention, a device adapted for attachment to a conventional smoking article comprises means for dividing a puff of smoke automatically into a first portion and at least one later portion and filter means arranged to filter the smoke portions produced differentially.
Suitably, the first smoke portion of the puff comprises the portion delivered during the first quarter to the first half of the duration of the puff.
Two embodiments of the invention, as applied to cigarettes, will now be more fully described by way of example and with reference to the accompanying drawings, in which:
FIGS. 1 and 2 are diagrammatic longitudinal sections through the said embodiments, and
FIG. 3 is a diagram in which pressure drop is plotted against time.
Referring to FIG. 1, the complete smoking article shown comprises a tobacco-containing section 1, a valve section 2 and a filter section 3. The section 1 may be of the nature of a conventional cigarette with tobacco 4 contained in a paper wrapping 5. The section 2 comprises a short cylinder 6 of cigarette diameter made of metal or a plastics material and attached in abutting relation to the section 1 by an adhesive band 7. A substantially complete narrow annular passage 8 or ring of narrow passages through the cylinder 6 near its periphery allows free flow of smoke during puffing. A larger axial passage 9 through the cylinder 6 is connected by axially spaced radial ports 10, 11 to a further substantially annular passage 12 extending for a substantial distance, but not completely through, the length of the cylinder. The axial passage 9 is normally obturated at the end adjacent to the section 1 by a resiliently loaded valve body. In the example, the valve body comprises a ball or spherical plug 13 retained in the obturating position illustrated, i.e. upstream of the radial ports 10, by a light helical compression spring 14 disposed in the axial passage 9. The filter section 3 secured in abutting relation to the section 2 by an adhesive band 15 comprises conventional fibrous or sheet tobacco-smoke-filtering material in a wrapper 16. At least the peripheral region 17 of the filter adjacent to the exit orifice of the annular passage 8 is of higher density, or has higher smoke-retention properties, than the inner or axial region 18, from which it is separated by a cylindrical paper sleeve 17'. A higher pressure drop is produced in the region 17 than in the region 18.
In use, when initial suction is applied to the smoking article through the section 3, smoke is drawn only through the narrow passage 8, the valve body 13 remaining in the obturating position. This initial portion of the puff passing through the passage 8 is filtered by the high-density filter region 17. As suction continues to be applied, the valve body 13 is retracted just pass the radial ports 10 and, while still closing the axial passage 9 for the middle portion of its length, permits smoke from the section 1 to pass into the annular passage 12 and so, via the ports 11, to the lower density filter region 18. The smoke path through the passage 8 and filter region 17 is thus bypassed to an extent which can be predetermined by design.
With such a device, the smoke produced during the earlier part of the puff is more strongly filtered, at 17, than the smoke of the later part of the puff, at 18, whereby more efficient filtration and a more desirable composition of the smoke entering the smoker's mouth can be ensured.
The smoking article of FIG. 2 differs from that of FIG. 1 in that the lower density inner filter region 18a is enclosed to the rear, as well as circumferentially, by the higher density filter material of the region 17a. A similar differential filtration effect is obtained.
FIG. 3 in which the pressure drop PD in smoking article in accordance with the invention is plotted against time T, illustrates, in general profile only, an example of a two-portion puff comprising a brief, initial, high peak 19 followed by a maintained lower value 20 of the pressure drop. The diagram is not dimensional, but the whole puff may, for the sake of example, be assumed to have a duration of about 2 seconds.