HK1192125B - Filter for smoking article - Google Patents

Description

Smoking article filter

The present application is a divisional application of patent application No. 201280023154.1 entitled "smoking article filter" filed on 13/11/2013.

Technical Field

The present invention generally relates to a filter for a smoking article.

Background

The term "smoking article" as used herein includes smokeable products such as cigarettes, cigars and cigarillos, whether based on tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco or tobacco substitutes, and also products which are heated but not combusted. The smoking article may be provided with a filter to remove components from the smoke stream.

The filter may contain additives such as flavourants to improve smoke.

The filter may have a movable element to control the air dilution value, the resistance to draw and/or the amount of flavourant added to the smoke stream. However, filters with movable elements are often complex and expensive to manufacture, or do not provide a very satisfactory smoking experience for the smoker.

Disclosure of Invention

According to one embodiment of the invention there is provided a filter for a smoking article, the filter comprising a first flow path through the filter, a second flow path through the filter, the second flow path being arranged to surround the first flow path, and a selector to selectively pass a flow of smoke through the first and second flow paths.

The selector may include a portion movable relative to the first and second flow paths to allow selection.

The first and second flow channels may extend coaxially along the filter, and the first flow channel may be disposed within the second flow channel.

The cylindrical first filter portion and the hollow cylindrical second filter portion surrounding the first filter portion may define first and second flow channels, respectively.

The extension of the first filter portion may be received in a recess in the selector, wherein the recess preferably narrows towards an end wall of the recess. The selector may include: a projection on an end wall of the recess extending into and engaging the first filter portion, and/or at least one further projection on one side wall of the recess, wherein the further projection is adapted to allow movement of the first filter portion towards the end wall of the recess during assembly and thereafter prevent movement in the opposite direction. The projection may be adapted to deform the first filter portion such that it engages with the side wall of the recess. A layer may be disposed between the first and second filter portions and may extend with the first filter portion into the recess.

Alternatively, the extension of the second filter portion may form a recess which receives the tubular portion of the selector, wherein the tubular portion preferably widens towards its end at the opening of the recess.

The selector may include: a first selector portion substantially fixed relative to the first and second filter portions; and a second selector part which is rotatable and/or axially movable relative to the first selector part.

The first selector portion may have a first set of one or more windows aligned with the first filter portion and a second set of one or more windows aligned with the second filter portion; and the second selector part may be rotatable relative to the first selector part and may have a third set of one or more windows alignable with the first set of windows to select the first flow path, or with the second set of windows to select the second flow path, or with a portion of the first and second sets of windows to select the portion of the first and second flow paths.

Alternatively, the first selector portion may have a first flow passage communicating with a first flow passage defined by the first filter portion and a second flow passage communicating with a second flow passage defined by the second filter portion; and the second selector part may be axially movable relative to the first selector part and may have a section adapted to open or close a first flow passage within the first selector part in dependence on the axial displacement. The portion and/or the section may have a conical shape. Alternatively, the portion may have a constant outer diameter; the sections may comprise two or more constant diameter sections separated by one or more steps; and the portion is movable into a selected one of the constant diameter sections, thereby allowing selection of one of two or more discrete levels of flow through the first flow channel. The filter may comprise a threaded connection between the first and second selector portions such that the axial displacement may be varied by means of a rotational force.

The at least one flow channel may include an additive. The filter may comprise an additive release member adapted to release the additive in response to being deformed and/or ruptured. The additive release member may be deformable and/or frangible by movement of a portion of the selector. The additive release member may be included in the selector. The portion of the second selector portion may be further adapted to force the additive release member against a portion of the first selector portion to release the additive. A portion of the first selector portion may include one or more protrusions adapted to cause the released additive to preferentially enter the first filter portion.

According to an embodiment of the invention, there is provided a filter for a smoking article, the filter comprising a first flow path through the filter, a second flow path through the filter and a portion movable relative to the first and second flow paths to allow fluid to selectively pass through the first and second flow paths, the second flow path being arranged to surround the first flow path.

According to an embodiment of the invention, there is provided a method of providing a sealed attachment between a first portion of filter material comprising a wrapper and a second portion made of a stiff material, the method comprising: providing a recess in the second portion, the recess having a convex shape on its end wall and/or a narrowing shape towards its end wall; and inserting the first portion into the recess thereby causing the projection and/or shape to deform the portion so that it engages the side walls of the recess.

Drawings

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

figure 1 shows an exploded perspective view of a smoking article comprising a filter according to a first embodiment of the invention;

figure 2 shows a cross-sectional view of the smoking article of figure 1;

figure 3 shows an end view of the smoking article of figure 1 in a first state (a), a second state (b) and a third state (c);

figure 4 shows an exploded perspective view of a smoking article comprising a filter according to a further embodiment of the invention;

figure 5 shows a cross-sectional view of a smoking article comprising a filter according to a further embodiment of the invention;

figure 6 shows a perspective view of a smoking article comprising a filter according to a further embodiment of the invention;

figure 7 shows an end view of the smoking article of figure 6 in a first state (a), a second state (b) and a third state (c);

figure 8a shows a cross-sectional view of a portion of a filter according to a second embodiment of the invention;

FIG. 8b is a first (proximal) end view of the selector illustrated in FIG. 8 a;

FIG. 8c is a second (distal) end view of the selector illustrated in FIG. 8 a;

figure 9a shows a cross-sectional view of a portion of a filter according to a third embodiment of the present invention;

FIG. 9b is a second (distal) end view of the selector illustrated in FIG. 9 a;

figure 10a shows a cross-sectional view of a portion of a filter according to a fourth embodiment of the present invention;

FIG. 10b is a second (distal) end view of the selector illustrated in FIG. 10 a;

figure 11a shows a cross-sectional view of a portion of a filter according to a fifth embodiment of the present invention;

FIG. 11b is a first (proximal) end view of the selector illustrated in FIG. 11 a;

FIG. 11c is a second (distal) end view of the selector illustrated in FIG. 11 a;

FIG. 12 is a close-up view of the highlighted area of FIG. 11a with the selector in the closed position (a) and in the first (b), second (c) and third (d) open positions;

figure 13a shows a cross-sectional view of a portion of a filter according to a sixth embodiment of the present invention;

FIG. 13b is a second (distal) end view of the selector illustrated in FIG. 13 a;

fig. 14 is a close-up view of the highlighted area of fig. 13a with the selector in the initial position (a) and in the release position (b), closed position (c) and open position (d).

Detailed Description

First embodiment

Figures 1 and 2 show a smoking article 10 comprising a filter 11 according to a first embodiment of the invention. The smoking article 10 includes a source of smokable material, preferably tobacco in the form of a cylindrical tobacco rod 12. The filter 11 is coaxially attached to the tobacco rod 12.

The filter 11 includes inner and outer filter portions 13,14 which define respective inner and outer flow passages through a body filter portion 15. The inner filter portion 13 includes an additive, such as a flavoring agent (not shown). The selector 16 at the end of the body filter portion 15 comprises first and second selector parts 17,18 which are rotatable relative to each other to select the adjustable part of one or both of the flow paths. Also included are barrier layer 19, inner and outer overwrap layers 20,21 and cover layer 22.

The outer filter portion 14 forms a hollow cylindrical tube having an outer diameter substantially the same as the outer diameter of the tobacco rod 12. The inner filter portion 13 forms a cylinder having a diameter and length that are substantially the same as the inner diameter and length, respectively, of the outer filter portion 14. The inner filter portion 13 is coaxially and co-peripherally arranged within the outer filter portion 14, thus forming a cylindrical body filter portion 15. The inner and outer filter portions 13,14 preferably have respective outer and inner diameters such that they have substantially the same cross-sectional area. For example, the outer filter portion 14 may have a diameter of about 7.8mm, while the inner filter portion 13 may have a diameter of about 5.4 mm. However, different cross-sectional areas may be used to provide filters 11 with different characteristics.

The inner and outer filter portions 13,14 each comprise a filtering material. The filtering material in each filter portion preferably comprises a homogeneous filtering material, such as conventional cellulose acetate tow. The term "homogeneous" is used to indicate that the filter material is substantially homogeneous in each filter portion 13,14 and, in particular, is homogeneous in a radial direction through each filter portion 13, 14. The inner and outer filter portions 13,14 may comprise different filtering materials or filtering materials having different physical properties, such as density and/or hardness.

The inner filter portion 13 contains an additive, which is preferably a flavourant, but may also be a different kind of additive. For example, the additive may be selected from one or more of the following: a flavoring agent (e.g., menthol, peppermint oil), a cooling agent (e.g., menthol) that provides a cooling sensation, or a smoke modifying agent (e.g., water, activated carbon). The additive is preferably included in an additive release member (not shown) from which it can be released by the smoker. The additive releasing means preferably comprises an additive in fluid form, preferably a liquid. The additive in the additive-releasing means may be a flavourant, such as menthol, or may be water. The additive release member preferably comprises a capsule having an outer wall, preferably made of a gum, and an inner space filled with the fluid additive. The additive release member may fracture or rupture under pressure, thereby releasing the additive. The additive release member provides selective release of the additive into the filter portion in which it is located. The filter portion contains the additive in a passive state prior to release of the additive, wherein the additive does not affect the smoke. The term "release" is meant to include leakage of the additive to the atmosphere, in addition to the act of physically releasing and opening the package. The term "release" indicates that the additive is functional and may have an effect on the smoking article 10. When packaged, the additive is dormant and does not affect.

The flavourant is preferably encapsulated to prevent it from migrating to the filter 11 or other parts of the smoking article 10 during storage. Encapsulation becomes especially important if the fragrance is menthol, which is relatively highly volatile. However, in some cases, the flavourant may be in powder form distributed throughout the filtration material or it may be applied to a substrate-e.g. a thread-embedded within the filtration material.

A barrier layer 19 is arranged between the inner and outer filter portions 13, 14. The barrier layer 19 is preferably made of a material that is substantially impermeable to liquid and gas flow, such as paper. The paper may be coated to be impermeable to liquid. The barrier layer 19 covers substantially the entire outer surface of the inner filter portion 13. The barrier layer 19 is preferably adhered to the inner filter portion 13 and/or secured therearound by a longitudinal seam of adhesive joining the opposed face edges. Thus, for example, when the smoking article 10 is in use, the barrier layer 19 blocks the passage of flavourant-laden or non-flavourant-laden smoke from the inner filter portion 13 to the outer filter portion 14 or vice versa, and also blocks the passage of flavourant from the inner filter portion 13 into the outer filter portion 14 after the flavourant has been released. The provision of the barrier layer 19 becomes particularly important if the flavourant is menthol of relatively high volatility.

The first selector portion 17 is formed with a plurality of openings or windows 23₁,23₂,24₁,24₂The opening or window extends axially over the entire length of the cylinder. The window comprises two outer windows 23₁,23₂And two inner windows 24₁,24₂. The first selector portion 17 has a diameter substantially equal to the diameter of the main body filter portion 15. The first selector portion 17 is coaxial with the body filter portion 15 and is joined to the body filter portion 15 at the end of the body filter portion 15 remote from the tobacco rod 12. The first selector part 17 is preferably made of a plastic material.

Each outer window 23 of the first selector part 17₁,23₂Having an annular sector-shaped cross section, i.e. the portion of the annulus between the two arcs and the two radial lines connecting the arcs. Outer window 23₁,23₂Is centred on the axis of rotation of the second selector part 18. The annulus has an outer diameter such that the first selector portion 17 has a relatively thin cylindrical wall surrounding the window and has an inner diameter substantially equal to the inner diameter of the outer filter portion 14. Outer window 23₁,23₂Each having an angular extent of about 90 deg., being rotationally offset from each other by about 180 deg., i.e. they are diametrically opposed.

Each inner window 24 of the first selector part 17₁,24₂Having an annular sector-shaped cross-section. Inner partWindow 24₁,24₂Is also centred on the axis of rotation of the second selector portion 18. The annulus has an outer diameter substantially equal to the outer diameter of the inner filter portion 13 and an inner diameter such that the first selector portion 17 has a relatively small central cylindrical cross-section. Inner window 24₁,24₂Each having an angular extent of about 90 deg., being rotationally offset from each other by about 180 deg., and being offset from the outer window 23₁,23₂There is a rotational offset of about 90.

The second selector part 18 forms a cylinder with two windows 25 extending axially over the entire length of the cylinder₁,25₂. The second selector part 18 has a diameter substantially equal to the diameter of the first selector part 17. The second selector part 18 is coaxial with the first selector part 17 and is connected to the first selector part 17 at the end of the first selector part 17 remote from the body filter part 15. The second selector part 18 is preferably made of a plastic material. Each window 25 in the second selector part 18₁,25₂Having a sector-shaped cross-section of a torus. Window 25₁,25₂Is centred on the axis of rotation of the second selector part 18. The annulus having an outer window 23 communicating with the first selector part 17₁,23₂Substantially equal outer diameter and inner window 24 of first selector part 17₁,24₂Substantially equal inner diameters. Window 25₁,25₂Have an angular extent of about 90 deg. and are rotationally offset from each other by about 180 deg.. The second selector part 18 is in a window 25₁,25₂The portion therebetween forms the louver 26₁,26₂。

The first and second selector parts 17,18 comprise means 27 for connecting them together. Preferably, the end face of the second selector 18 facing the first selector part 17 comprises a centrally axially extending pin 28. The first selector part 17 has a central socket 29 on its opposite end face. The pin 28 and the socket 29 are form-matched to each other such that once they engage each other they form a connection that substantially prevents relative displacement of the first and second selector parts 17,18 in either the axial or radial direction while allowing relative rotation. For example, the pin 28 may have an enlarged end cross-section at its distal end and the socket 29 may have a complementary shape, such that the pin 28 snaps into the socket 29.

The inner wrap 20 surrounds the body filter portion 15 and the first selector portion 17. The inner wrapper 20, such as a plug wrap, is preferably a porous paper but may also be a non-porous paper. The inner wrapper 20 is adhered to the body filter portion 15 and the first selector portion 17 and/or secured around them by a longitudinal seam of adhesive connecting the opposing edges. Thus, the wrapper layer helps to secure the body filter portion 15 and the first selector portion 17 together, for example during manufacture. In some cases, the inner wrapper 20 may be omitted.

An outer wrap 21 surrounds the inner wrap 20 and the adjacent length of tobacco rod 12. The overwrap layer 21, such as plug wrap, is preferably a porous paper but may also be a non-porous paper. The outer wrapper 21 is adhered to the inner wrapper 20 and the length of tobacco rod 12 and/or secured around them by a longitudinal seam of adhesive connecting the opposite edges. Thus, the overwrap layer 21 connects the body filter portion 15 to the tobacco rod 12 and forms a seal against the ingress of air between the body filter portion 15 and the tobacco rod 12 in use, for example when a smoker draws on the smoking article 10.

A cover layer 22 surrounds second selector portion 18 and overwrap layer 21. The cover layer 22 is preferably made of a paper material, such as tipping paper. A cover layer 22 is adhered to at least a portion of the outer surface of the second selector portion 18. The cover layer 22 is also secured by a longitudinal seam of adhesive connecting the opposite edges, thus forming a cylindrical sleeve. A snug fit is formed between the cover layer 22 and the overwrap layer 21 which forms a seal between the cover layer 22 and the overwrap layer 21 during use that resists the ingress of air. Also, the filter 11 is adapted so that friction between the cover layer 22 and the outer wrapper 21 and between the first and second selector parts 17,18 allows the cover layer 22 and the adhered second selector part 18 to be easily turned by the smoker, rather than having them fixed in place.

Use of the first embodiment

In use, a smoker can manipulate the filter 11 to control the flavour of the smoke.

In the initial inactive state, the flavourant is encapsulated and therefore the smoke drawn from the filter 11 is odourless irrespective of whether the first and second selector parts are rotated relative to each other.

The smoker can activate the filter 11 by applying inward radial pressure and thereby deforming the body filter portion 15 and the additive release member or capsule contained therein. This causes the capsule to rupture and release the flavoring.

Fig. 3a shows the filter 11 in one of two positions corresponding to the first activation state. The other of the two positions is obtained by rotating the second selector part 18 by 180 deg. with respect to the first selector part 17. In this state, when the window 25 of the second selector part 18 is opened₁，25₂And an inner window 24 of the first selector part 17₁，24₂In alignment, the louvers 26 of the second selector portion 18₁，26₂And an outer window 23 of the first selector part 17₁，23₂And (6) aligning. In other words, the outer window 23₁，23₂Inner window 24 is closed₁，24₂And (4) opening. Thus, when a smoker draws on the smoking article 10, smoke is directed through the inner filter portion 13, which contains the released flavourant, and is not directed through the outer filter portion 14. The smoke drawn from the selector 16 will therefore have the strongest flavour, the concentration of which will depend on the characteristics of the inner filter portion 13.

During manufacture, the filter 11 is preferably arranged in a position such that, after activation of the filter 11 by the smoker, the filter 11 is in the first activation state and the smoke drawn from the selector 16 has the strongest flavour.

The smoker can grip and rotate the overlay 22 relative to the tobacco rod 12 such that the second selector portion 18 rotates relative to the first selector portion 17. This changes the filter 11 between a first activation state and second and third states corresponding to the most intense flavoured, flavourable and flavourless smoke respectively. Thus, after release of the flavourant, the smoker can still adjust the concentration of flavour in the smoke and even return to the non-flavoured smoke.

Fig. 3b shows the filter 11 in a position corresponding to the second activation state. In this state, when the window 25 of the second selector part 18 is opened₁，25₂And an outer window 23 of the first selector part 17₁，23₂With partial alignment, the louvers 26 of the second selector portion 18₁，26₂And an inner window 24 of the first selector part 17₁，24₂Partially aligned. In other words, the outer and inner windows 23₁，23₂，24₁，24₂Are all partially open. Thus, when a smoker draws on the smoking article 10, smoke is directed through both the inner and outer filter portions 13, 14. The smoke drawn from the selector 16 will thus include both flavoured smoke and non-flavoured smoke. The concentration of the flavour in the smoke will depend on the ratio of flavoured and unscented smoke. Depending on the outer and inner windows 23₁，23₂，24₁，24₂The relative degree of opening and thus the relative angle of rotation of the first and second selector portions 17, 18.

Fig. 3c shows the filter 11 in one of two positions corresponding to the third activation state. The other of the two positions is obtained by rotating the second selector part 18 by 180 deg. with respect to the first selector part 17. In the first active state, when the window 25 of the second selector part 18 is open₁，25₂And an outer window 23 of the first selector part 17₁，23₂In alignment, the louvers 26 of the second selector portion 18₁，26₂And an inner window 24 of the first selector part 17₁，24₂And (6) aligning. In other words, the inner window 24₁,24₂Is turned off, andand an outer window 23₁,23₂Is open. Thus, when a smoker draws on the smoking article 10, smoke will be directed through the outer filter portion 14 and will not be directed through the inner filter portion 13. The smoke drawn from the selector 16 is therefore unscented.

As the smoker rotates the cover 22 relative to the tobacco rod 12 from the position corresponding to the first most intense flavour state, the concentration of flavour in the smoke progressively decreases until the smoke becomes non-flavoured, i.e. the position corresponding to the third state, after a 90 ° clockwise or anticlockwise rotation.

Conversely, as the smoker rotates the cover 22 relative to the tobacco rod 12 from the position corresponding to the third, non-flavoured state, the concentration of flavour in the smoke progressively increases until the smoke flavour is strongest after 90 ° clockwise or anticlockwise, i.e. the position corresponding to the first state.

The cover layer 22 and a section of the tobacco rod 12 adjacent one end of the cover layer 22 are preferably provided with markings (not shown) which indicate the different states of the filter 11. The indicia may include a scale to indicate the intensity of the smoke scent.

It will also be appreciated that if additives other than flavourants are used, the different states of the filter 11 will correspond to different amounts of smoke modification, rather than different flavour concentrations of the smoke.

Variations of the first embodiment

Some variations and modifications of the filter 11 will now be described. It is to be appreciated that any feature described in any embodiment may be combined with any other feature in any other embodiment.

Figure 4 shows a smoking article 10 'comprising a filter 11' according to a further embodiment of the invention. Filter 11' is similar to filter 11 (fig. 1). In this embodiment, however, the modified second selector portion 18' includes a body portion 30 and a sleeve portion 31. The body portion 30 has the same cross-section as the second selector portion 18 (fig. 1) of the first embodiment, but is shorter in length, i.e. relatively thin. The sleeve portion 31 is a thin-walled cylindrical tube having an outer diameter substantially equal to that of the body portion 30. The sleeve portion 31 extends coaxially from an end surface of the body portion 30 facing the first selector portion 17'. The sleeve portion 31 surrounds and forms a sliding fit around a section of the first selector portion 17'. This increases the mechanical strength of the selector 16 ' and also forms a seal between the first and second selector parts 17 ', 18 ' in use, which blocks the ingress of air.

In the embodiment shown in fig. 4, the modified first selector portion 17' comprises a body portion 32 and two sleeve portions 33, 34. The body portion 32 has the same cross-section as the second selector portion 17 (fig. 1) of the first embodiment, but is shorter in length, i.e. relatively thin. The sleeves 33,34 are thin-walled cylindrical tubes that extend coaxially from the end surface of the body portion 32 that faces the body filter portion 15'. The first sleeve part 33 has an outer diameter substantially equal to the main body part 30, and the second sleeve part 34 is arranged such that it forms two concentric chambers within the first selector part 17 ', one of which connects the inner filter part 13' with the inner window 24₁’,24₂'connected and the other connecting the outer filter portion 14' with the outer window 23₁’,23₂' connect. The first and second sleeve portions 33,34 are preferably tapered such that they each have a thin rounded edge at the end near the main body filter portion 15'. Thus, the first and second sleeve portions 33,34 may encircle a section of the outer and inner filter portions 14 ', 13', respectively. This arrangement may help improve the seal between the first selector portion 17 'and the main body filter portion 15'. In particular, the first sleeve portion 33 can help block gas from entering the first selector portion 17 ', and the second sleeve portion 34 can help block smoke from the inner filter portion 13' from reaching the outer window 24₁’,24₂'or smoke from the outer filter portion 14' to the inner window 23₁’,23₂'. The modified first and second selector portions 17 ', 18' can also provide for lighter weight and/or be moreA compact selector.

In the embodiment shown in fig. 4, the modified cover layer 22 'does not surround the second selector portion 18', but it is used to connect the body filter portion 15 'to the tobacco rod 12'. Therefore, the outer layer 21 (fig. 1) can be omitted. In this case, the cover layer 22 'surrounds a section of the first connector portion 17', the body filter portion 15 ', and a section of the tobacco rod 12' and is adhered to and/or fastened around them. Thus, unlike the first embodiment in which the cover layer 22 (fig. 1) is retained and rotated relative to the tobacco rod 12 (fig. 1), for example, the smoker can retain and rotate the second selector portion 18' itself.

The seal between the first and second selector portions 17 ', 18 ' is such that, in use, air is substantially prevented from entering between them by the modified cover layer 22 '. Thus, the modified overlay layer 22 'preferably incorporates the modified second selector portion 18'. However, a modified overlay layer 22' may also be used for the second selector portion 18 (fig. 1) of the first embodiment. A modified second selector portion 18' may also be used for the overlay 22 (fig. 1) of the first embodiment.

Figure 5 shows a smoking article 10 "comprising a filter 11" according to a further embodiment of the invention. The filter 11 "is similar to the filter 11 except that the modified cover layer 22" has an extension 22 "a that surrounds and is adhered to and/or secured around the second selector portion 18". The extended portion 22 "a is separated from the other portion 22" of the cover layer by a perforated line 35, the perforated line 35 preferably surrounding where the first and second selector portions 17 ", 18" meet. Thus, the cover layers 22 ", 22" a weakly connect the first and second selector parts 17 ", 18" to each other. This can help to maintain their original relative orientation, for example, at the location corresponding to the first strongest scent state. When the smoker first rotates the second selector part 18 "relative to the first selector part 17", the cover layer 22 ", 22" a tears along the perforation line 35, thus providing tactile and/or audible feedback to the smoker.

Alternatively, for example in the first embodiment (fig. 1), the inner and/or outer package layers 20,21, but not the cover layer 22, may have extensions to weakly connect the first and second selectors 17,18 to each other.

In the embodiment shown in fig. 5, the first selector part 17 "comprises a connection plug 36, i.e. a hollow cylindrical sleeve, which extends axially from the center of the end surface of the first selector part 17" facing the body filter part 15 ". The connection plug 36 engages in a recess provided in the centre of the mutually facing end surfaces of the inner filter part 13 ″. The connection plug 36 preferably has an outer diameter substantially equal to the outer diameter of the inner filter portion 13 "and an inner diameter equal to the inner window 23' of the first selector portion 17 ″.₁,23’’₂Are substantially equal in outer diameter. Connection plug 36 helps to prevent smoke from entering outer window 24' from inner filter portion 13 ″.₁,24’’₂Or smoke from the outer filter portion 14 '' into the inner window 23 ''₁,23’’₂。

The embodiment shown in fig. 5 can be easily made using the following method: in this method two ' back-to-back ' connected filter portions 11 ' are wrapped together simultaneously with two tobacco rods 12 ' and then cut transversely to form two smoking articles 10 '.

Figure 6 shows a smoking article 10 "'comprising a filter 11"' according to a further embodiment of the invention. The filter 11 '"is similar to the filter 11' (fig. 4). In this embodiment, the first selector portion 17 "' has only one outer window 23" ' and only one inner window 24 "'. The outer window 23 "'and the inner window 24"' correspond respectively to one of the outer windows 23 '(fig. 4) and to one of the inner windows 24' (fig. 4) described above, except that they each have an angular extent of about 180 ° and a rotational offset from each other of about 180 °. In addition, the second selector portion 18 "' has only one window 25" ', which corresponds to one of the windows 25 ' (fig. 4) described above, except that it has an angular range of about 180 °.

Fig. 7 shows the filter 11 "' in a position corresponding to the first, second and third activation states. A clockwise or counterclockwise rotation of 180 ° changes the filter 11' ″ from the first state to the third state via the second state and vice versa. This enables the smoker to more accurately control the concentration of the flavour.

The number of windows or the size or shape or arrangement of the windows of the first and second selector parts may be different from the above described embodiments. For example, referring to fig. 1, the window 25 of the second selector part 18 may extend over a smaller angle than the windows 23,24 of the first selector part 17. Thus, there is a range of angles in which the filter 11 is in the first most flavoured state or the third non-flavoured state. This allows the smoker to select these conditions more easily.

The filter may include a mechanism to provide indexing for relative rotation between the first and second selector portions, thereby limiting rotation, and/or providing tactile and/or audible feedback to the smoker during rotation.

For example, referring to fig. 1, the opposite end surfaces of the first and second selector portions 17,18 may be provided with first and second indexing members, respectively. The first indexing member preferably has a plurality of elongate recesses separated by ridges which extend substantially radially. The ridges between adjacent depressions may have a curved profile or may have a pointed, corrugated or tapered profile. The second indexing member may have substantially the same profile and configuration as the first indexing member, in which case the first and second indexing members may each be provided with a projection which engages with a recess of the other of the first and second indexing members. The mechanism 27 connecting the first and second selector portions 17,18 is resiliently deformable so as to allow the raised features of each component to be releasably engaged.

Thus, relative rotation of the first and second selector parts 17,18 is blocked until sufficient force is applied to rotate to the next index position. This helps prevent accidental rotation from the initial or smoker selected position. The indexing mechanism preferably defines a plurality of positions corresponding to different filter states. For example, there may be five locations, one location corresponding to the first most intense fragrance state ("100%"), three different locations corresponding to the second partial fragrance state ("75%", "50%" and "25%"), and one location corresponding to the third no fragrance state ("0% fragrance"). The indexing mechanism may also be adapted to limit the rotation to a predetermined angular range, for example a 90 ° range between the position corresponding to the first strongest fragrance state and the position corresponding to the third non-fragrance state. The indexing mechanism also provides feedback to the smoker in the form of touch and/or sound during rotation, such as a click when each indexed position is engaged.

Alternatively, the first and second indexing mechanisms may be provided on the inner and outer surfaces of the outer wrapper layer 21 and the cover layer 22, respectively, or on the modified first and second connector portions 17 ', 18' (fig. 4), respectively.

Instead of the selector 16 (fig. 1), other types of selectors may be used, such as mechanical baffles to select between inner and outer flow paths.

Instead of rotating, portions of the selector may be slidable or otherwise movable relative to each other.

For example, referring to fig. 1, the socket 29 of the first selector part 17 may extend radially so that the pin 28 on the second selector part 18 may slide along it. Also, the pin 28 may have a square or rectangular cross-section such that it cannot rotate within the socket 29. In this case, the windows 23,24,25 of the first and second selector parts 17,18 are arranged such that smoke can be guided only through the inner filter part 13, only through the outer filter part 14 or through the adjustable parts of the inner and outer filter parts 13, 14.

Alternatively, the selector parts 17,18 may slide relative to each other in the axial direction rather than in the radial direction. For example, the selector portions 17,18 may each comprise a hollow cylindrical portion, one of which is adapted to be slidably fitted within the other, and which has one or more windows in its circumferential wall, which can be opened or closed by sliding the selector portions 17,18 axially relative to each other.

The selector parts 17,18 may also be helically movable relative to each other, for example by providing them with complementary screw threads.

The additive releasing means, e.g. the encapsulated flavourant, may be arranged such that the filter 11 can be activated by moving the second selection means 18 in some way, e.g. away from its initial position. For example, second selection device 18 may be secured to cover layer 22 and may include one or more protrusions on an inner surface of cover layer 22. These projections may be arranged such that when the cover layer 22 is rotated relative to the body filter portion 15, the projections are pressed onto the filter portion comprising the capsule, or onto the capsule itself, thereby deforming the capsule and causing them to rupture and release the flavourant

Second embodiment

Fig. 8a,8b and 8c show different views of a part of a filter 51 according to a second embodiment of the invention. The filter 51 includes a body filter portion 52 having one end attached to one end of a tobacco rod (not shown) similar to the tobacco rod 12 in the first embodiment and the other end attached to a selector 53. The selector 53 comprises first and second selection means 54, 55. As described in more detail below, the second selection means 55 is attached to the body filter portion 52, and the first selection means 54 is movably attached to the second selection means 55. The tobacco rod, body filter portion 52, and first and second selection means 54,55 are generally cylindrical, have similar outer diameters, and are coaxially disposed so as to define an axis 56.

The relative axial positions of portions of the filter 51 will be described below as if the filter 51 were positioned such that the tobacco rod is at the distal end of the filter 51. The words "near" and "far" should also be understood accordingly. This is merely for convenience. It should be appreciated that the filter 51 may be positioned in any manner.

The body filter portion 52 includes inner and outer filter portions 57,58 which define respective inner and outer flow passages. The inner and outer filter portions 57,58 are identical to the inner and outer filter portions 13,14 of the first embodiment, except that they have different lengths as described in more detail below. As in the first embodiment, the inner filter portion 57 includes an additive, such as a flavoring agent, preferably contained in an additive release member (not shown).

An intermediate layer 59 is disposed between the inner and outer filter portions 57, 58. The intermediate layer 59 is the same as the barrier layer 19 of the first embodiment.

The inner filter portion 57 can have an additional plug wrap (not shown). The outer filter portion 58 can also have a plug wrap (not shown).

The first and second selection means 54,55 can be made of a plastic material or other suitable material.

As can be seen, the first and second selection devices 54,55 are movable relative to each other to adjustably open and close the inner flow path within the second selection device 54, the outer flow path of the device being open during this action.

The first selection means 54 comprises a generally cylindrical outer tube portion 54a and a generally cylindrical inner portion 54 b. The axes of portions 54a and 54b coincide with axis 56. The portions 54a,54b are substantially coextensive. Portion 54b is solid except that it includes a recess 54c, which will be described in more detail below. An annular space 54d between the portions 54a,54b defines a flow path through the first selection device 54. The portions 54a,54b are connected to one another by a plurality of radially extending structures ("spokes") 54 e. Each spoke 54e has an elongated rectangular cross-section that is aligned with the axis 56. Spoke 54e extends from the proximal end of first selection device 54 for part of its length.

The second selection means 55 comprises a generally cylindrical outer tube portion 55a, a generally cylindrical intermediate tube portion 55b and a generally cylindrical inner solid portion 55 c. The axes of the portions 55a, 55b, 55c coincide with the axis 56. The outer and middle portions 55a, 55b are substantially coextensive, while the inner portion 55c (excluding the projection 55d and pin 55e as described in more detail below) is shorter and centrally disposed relative to the other portions 55a, 55 b. The intermediate portion 55b divides the second selection device 55 into inner and outer spaces 55f, 55g, thereby defining respective inner and outer flow channels. The middle and inner portions 55b, 55c are connected to each other by a plurality of inner spokes 55 h. The outer and intermediate portions 55a, 55b are connected to each other by a plurality of outer spokes 55 i. The spokes 55h, 55i are similar to the spokes 54e in the first selection device 54.

The first and second selection means 54,55 are attached to each other by a threaded connection. The inner portion 55c of the second selection means 55 comprises a threaded cylindrical projection 55d which cooperates with a threaded cylindrical recess 54d of the inner portion 54c of the first selection means 54. Thus, the smoker can control the relative axial position of the first and second selection means 54,55 by rotating one relative to the other. The projection 55d and the recess 54d can comprise matching portions (not shown) to differentiate angularly the rotation and thereby the axial displacement and/or to define a stop position corresponding to a maximum axial separation of the first and second selection means 54, 55. Alternatively, such indexing and/or stop positions can be otherwise defined or undefined.

A section at the proximal end of the outer portion 55a of the second selection means 55 has a reduced outer diameter. Which internally matches the section proximal to the outer portion 54a of the first selection device 54. As shown, portion 54a can have an annular ridge 54f on its inner wall that engages the outer wall of portion 55a, and portion 55a can have an annular ridge 55f on its outer wall that engages the inner wall of portion 54 a. The ridges 54f, 55j serve to form a relatively low friction seal between the first and second selection devices 54, 55. The seal is to prevent air from being drawn into the first selection device 54 (or to limit the amount of such air). Alternatively, the ridges 54f, 55j can be omitted and such a seal formed directly between the inner and outer walls of the respective portions 54a, 55 a.

The inner filter portion 57 is longer than the outer filter portion 58 and projects from the proximal end of the main body filter portion 52. The intermediate layer 59 is coextensive with the inner filter portion 57. The protruding portion of the inner filter portion 57 is received in the interior space 55f of the distal end of the second selection means 55. The distal end of the inner space 55f has a tapered (conical) portion. The taper is such that at the distal end of the taper, the interior space 55f is wider than the width of the inner filter portion 52 (when undeformed) and at the proximal end of the taper, it is narrower. Thus, when assembled (as shown), the inner filter portion 57 deforms and forcibly engages the intermediate portion 55 b. This arrangement serves to hold the second selection means 55 and the body filter portion 52 together and forms a seal which prevents the passage of additive between the inner and outer flow paths. Furthermore, this arrangement makes assembly of the filter 51 easier and reduces the risk of damaging the intermediate layer 59 during assembly.

Thus, the inner flow path defined by the inner filter portion 57 is connected to the inner flow path defined by the interior space 55f within the second selection means 55, while the outer flow path defined by the outer filter portion 58 is connected to the outer flow path defined by the exterior space 55g in the second selection means 55.

An elongated pin 55e is provided on the distal wall of the inner portion 55c of the second selection means 55. The longitudinal axis of the pin 55e coincides with the axis 56. The pin 55e extends axially towards (or beyond) the distal end of the second selection means 55. The pin 55e is received in a hole in the inner filter portion 57 and friction therebetween holds the second selection means 55 and the main body filter portion 52 together. The holes may be preformed or may be formed by the pins 55e during assembly. As shown, the pin 55e can have a cruciform cross-section that decreases in size toward its distal end. Alternatively, the pin (or pins) may have a different shape.

The inner portion 54b of the first selection means 54 and the intermediate portion 55b of the second selection means are arranged such that they can cooperate with each other to open or close the inner flow channel within the second selection means 55 depending on the relative axial position of the first and second selection means 54, 55. The inner space 55f in the second selection means 55 has a tapered (conical) part towards its proximal end, wherein the taper is arranged such that the space 55f is wider at its proximal end. In addition, the inner portion 54b of the first selection means 54 has a tapered (conical) portion towards its distal end, wherein the taper is arranged such that the portion 54b is narrower at its distal end. The taper of the portion 55b is slightly shallower than the taper of the space 55 f.

In the closed position (as shown in the figures), the area of the inner portion 54b of the first selection means 54 is pressed against the area of the inner wall of the intermediate portion 55b of the second selection means 55. Thus, a portion of space 55f is sealed and no fluid enters the flow path in first selection device 54 from the inner flow path in second selection device 55. The smoking article will typically be provided with the selector 51 in the closed position.

In the open position, in which the first and second selection devices 54,55 are further separated, a gap is created between the inner portion 54b of the first selection device 54 and the middle portion 55b of the second selection device 55. The gap allows fluid to pass from the internal flow channel in second selection device 55 into the flow channel in first selection device 54. The size of the gap increases as the axial separation of the first and second selection means 54,55 increases. Thus, the flow resistance through the slit is reduced and thus the ratio of the fluid passing through the inner flow channel to the fluid passing through the outer flow channel is increased (because the resistance of the outer flow channel is constant). If, for example, the inner filter portion 57 contains a fragrance (which may be released from the additive releasing means as described above with reference to the first embodiment), this ratio corresponds to a particular fragrance concentration. Thus, the fragrance concentration can be increased or decreased by increasing or decreasing the separation of the first and second selection means 54, 55.

As mentioned above, the relative movement of the first and second selection means 54,55 can be angularly differentiated. For example, the indexed (or differentiated angular) position may correspond to a closed position and one or more different open positions.

The filter 51 can be attached to the tobacco rod by a cover layer (not shown). The overlay 60 can be made of tipping paper or other suitable material. In some embodiments, the cover layer can be secured around the first and second selection means 54,55, the body filter portion 52 and a section of the tobacco rod, and can have a perforation line or other line of weakness around where the first and second selection means 54,55 meet. The perforation line is broken when the first selection means 54 is first rotated relative to the second selection means 55. Alternatively, the cover layer may have two portions, a first portion secured around the first selection device 54 and a second portion secured around the second selection device 55, the body filter portion 52 and a section of the tobacco rod. In such an embodiment, the first portion of the cover layer can overlap (rather than be secured to) the second portion of the cover layer, thereby providing a greater gripping area for the smoker when the first selection means 54 is rotated relative to the second selection means 55. The cover layer may be provided with markings (not shown) to indicate various positions or for example the fragrance concentration.

Third embodiment

Fig. 9a and 9b show different views of a selector 53' comprised in a filter according to a third embodiment of the invention. The selector 53 'is identical to the selector 53 of the second embodiment, except that first, the pin 53 e' is wider at its "proximal" end (the end remote from the tobacco rod) and/or adds a considerable width to the pin 53e of the first embodiment. Second, the space 55 f' for receiving the inner filter portion (not shown) need not be tapered (conical) but may have a right circular cylindrical shape. This is because, in this embodiment, the pins 53 e' deform the inner filter portion so that its outer surface is forced radially outwardly and into forceful engagement with the inner wall of the intermediate portion 55 b. As explained above, this engagement holds second selection device 55 and body filter portion 52 together and forms a seal that prevents passage of additive between the inner and outer flow channels. Alternatively, assuming that pin 53e 'is wide enough, space 55 f' may be tapered such that it is wider towards its proximal end. Also, the pin 53 e' need not have the form shown and may have any suitable form to deform the inner filter portion in the manner described above.

Fourth embodiment

Fig. 10a and 10b show different views of a selector 53 "comprised in a filter according to a fourth embodiment of the invention. The selector 53 "is identical to the selector 53 in the second embodiment, except that additional features are provided to more securely hold the second selection means 55" with the body filter portion (not shown). These additional features are a plurality of barb-like structures ("barbs") 101 provided on the inner wall of the intermediate portion 55b "of the second selection means 55". As shown, there can be 4 barbs 101 that are more evenly distributed around the inner wall of the middle portion 55b ". Alternatively, there may be a different number of barbs 101. Also, the barbs can be placed in different locations, and in some embodiments, the barbs can be placed on the pins 55e ″. As shown, each barb 101 may be generally wedge-shaped with a slightly inclined side 101a and a steeply inclined side 101b oriented toward the "distal" end of second selection device 55 "(i.e., toward an end of the tobacco rod). The slightly inclined side 101a can also narrow towards the distal end of the second selection means 55 ". Alternatively, the barbs 101 can have different shapes. In either case, the barb 101 is provided such that the inner filter portion (not shown) can be moved relatively easily into the second selection means 55 "during assembly, but is then prevented from moving out of the second selection means 55" by the barb 101.

Fifth embodiment

Fig. 11a, 11b and 11c show different views of a part of a filter 151 according to a fifth embodiment of the invention. The filter 151 comprises a body filter portion 152, one end of which is attached to one end (not shown) of a tobacco rod similar to the tobacco rod 12 of the first embodiment, and the other end of which is attached to a selector 153. The selector 153 includes first and second selection devices 154, 155. As will be described in more detail below, second selection means 155 is attached to body filter portion 152, and first selection means 154 is movably attached to second selection means 155. The tobacco rod, body filter portion 152, and first and second selection means 154,155 are generally cylindrical/cylindrical, have similar outer diameters, and are coaxially aligned, thus defining an axis 156.

The words "near" and "far" are understood in the same manner as in the second embodiment.

The body filter portion 152 includes inner and outer filter portions 157, 158 that define respective inner and outer flow channels. The inner and outer filter portions 157, 158 are identical to the inner and outer filter portions 13,14 of the first embodiment, except that they have different lengths as explained in more detail below. As in the first embodiment, the inner filter portion 157 includes an additive, such as a flavoring agent, preferably in an additive release element (not shown).

An intermediate layer 159 is disposed between the inner and outer filter portions 157, 158. The intermediate layer 159 is the same as the barrier layer 19 of the first embodiment.

The inner filter portion 157 may have an additional plug wrap (not shown). The outer filter portion 158 may also have a plug wrap (not shown).

First and second selection devices 154,155 may be made of plastic or other suitable material.

Similar to the second embodiment, the first and second selection means 154,155 are movable relative to each other so that the inner flow channel in the second selection means 155 can be adjustably opened and closed. In this embodiment, however, the inner flow path has a plurality of discrete open states.

The first selection means 154 includes an outer generally cylindrical sleeve portion 154a and an inner generally cylindrical portion 154 b. The axes of the portions 154a,154b coincide with the axis 156. The portions 154a,154b are largely coextensive. Portion 154b is solid except that it has a notch 154 c. An annular space 154d between the portions 154a,154b defines a flow passage through the first selection device 154. The portions 154a,154b are connected to one another by a plurality of spokes 154e similar to the spokes 54e of the second embodiment.

Second selection means 155 includes an outer generally cylindrical sleeve portion 155a, an intermediate generally cylindrical sleeve portion 155b and an inner generally cylindrical solid portion 155 c. The axes of portions 155a,155b and 155c coincide with axis 156. Outer and intermediate portions 155a,155b are axially offset from each other, outer portion 155a being located towards the proximal end of second selection means 155 and intermediate portion 155b being located towards the distal end of second selection means 155. The inner portion 155c is largely coextensive with the intermediate portion 155 b. Inner portion 155b separates second selection device 155 into inner and outer spaces 155f,155g, defining respective inner and outer flow channels. The middle and inner portions 155b,155c are connected to each other by a plurality of inner spokes 155 h. The outer and middle portions 155a,155b are connected to each other by a plurality of outer spokes 155 i. Spokes 155h,155i are similar to spokes 154e in first selection device 154.

The first and second selection means 154,155 are attached to each other by a threaded connection. A segment of the distal end of first selector member 154 has a reduced outer diameter and fits within a segment of the proximal end of outer portion 155a of second selector member 155. The outer wall of first selection means 154 and the inner wall of outer portion 155a of second selection means 155 comprise cooperating threaded portions 154f,155 k. Thus, the smoker can control the axial relative position of the first and second selection means 154,155 by rotating relative to each other. The threaded portions 154f,155k may comprise cooperating portions (not shown) for angularly differentiating the rotation and therefore the axial displacement and/or defining a stop position corresponding to a maximum axial separation of the first and second selection means 154, 155. Alternatively, such indexing and/or stop positions can be defined otherwise or not. The threaded connection can form a seal that prevents air from being drawn into the first selection device 154 (or limits the amount of such air). There is also a contact area between the outer wall of device 154 and the non-threaded portion of the inner wall of portion 155a, as shown. The contact area may also form a seal.

The proximal end of inner portion 155c of second selection means 155 is received by notch 154d of inner portion 154c of first selection means 154. This arrangement helps maintain coaxial alignment of first and second selection devices 154, 155.

The inner filter portion 157 is shorter than the outer filter portion 158, leaving a cylindrical recess at the proximal end of the main body filter portion 152. The intermediate layer 159 is coextensive with the outer filter portion 158. The intermediate and inner portions 155b,155c of the second selection means 155 extending from the second selection means 155 are received in the recess of the body filter portion 152. Intermediate portion 155b of second selection device 155 has a tapered (conical) portion at its distal end. The taper is arranged such that at the distal end of the taper, portion 155b is narrower than the width of the cylindrical recess in the main body filter portion 152 (when undeformed), and it is wider at the proximal end of the taper. Thus, when assembled (as shown), the outer filter portion 157 is deformed by the intermediate portion 155b and forcibly engages the intermediate portion 155 b. This arrangement holds second selection means 155 and body filter portion 152 together and forms a seal that prevents passage of additive between the inner and outer flow channels. Moreover, this arrangement makes it easier to assemble the filter 151 during assembly and reduces the risk of damaging the intermediate layer 159.

Thus, the inner flow path defined by the inner filter portion 157 is connected to the inner flow path defined by the interior space 155f in the second selection means 155, while the outer flow path defined by the outer filter portion 158 is connected to the outer flow path defined by the exterior space 155g in the second selection means 155.

The inner portion 154b of the first selection means 154 and the intermediate portion 155b of the second selection means are arranged such that they can cooperate with each other to open or close the inner flow channel in the second selection means 155 depending on the relative axial position of the first and second selection means 154, 155. As mentioned above, in this embodiment, there are a plurality of discrete open states.

Fig. 12a,12b,12c and 12d show the filter 151 in a closed position and three different open positions, respectively, as described below.

Second selection device 155 has annular ridge 155m on the inner wall of intermediate portion 155 b.

In the closed position (as shown in fig. 11a and 12 a), the distal wall of the inner portion 154b of the first selection means 154 is pressed to the proximal side of the ridge 155 m. Thus, a section of space 155f in second selection device 155 is sealed and no fluid enters the flow channels in first selection device 154 from the inner flow channels in second selection device 155. The smoking article is normally provided with the selector 151 in the closed position.

There are a plurality of steps 155n between the ridge 155m and the proximal end of the intermediate portion 155b where the inner diameter of the intermediate portion 155b changes. At each step 155n, the inner diameter increases in a direction towards the proximal end of second selection means 155. There may be two such steps 155n as shown. Alternatively, there may be a different number of steps or no steps. In the case of two steps, there is a first section of portion 155b having a first inner diameter, a more proximal second section having a second inner diameter, the second inner diameter being greater than the first inner diameter, and an even more proximal third section having a third inner diameter, the third inner diameter being greater than the second inner diameter. The length of each section between steps 155n is greater than the height of steps 155 n.

In the open position, in which the first and second selection means 154,155 are further separated, there is a gap between the portion 154b and the ridge 155 m. The gap allows fluid to pass from the internal flow channel in second selection device 155 into the flow channel in first selection device 154.

In a first open position (as shown in fig. 12 b), portion 154b is in a position such that it extends approximately half way into a first segment of portion 155b having a first inner diameter. The resistance of fluid through the gap between the outer wall of portion 154b and the inner wall of portion 155b depends on the size of the gap.

In the second open position (as shown in fig. 12 c), portion 154b is in a position such that it extends approximately half way into the second section of portion 155 b. Because portion 155b has a larger inner diameter in the second section than in the first section, the gap between the outer wall of portion 154b and the inner wall of portion 155b in the second open position is larger than in the first open position. Thus, the resistance of the fluid passing through the gap is reduced.

In the third open position (as shown in fig. 12 d), portion 154b is in a position such that it extends approximately half way into the third section of portion 155 b. Because the third section of portion 155b has a larger inner diameter than the second section, the gap between the outer wall of portion 154b and the inner wall of portion 155b in the third open position is larger than in the second open position. Thus, the resistance of the fluid passing through the gap is reduced.

In each case, the decreasing resistance of the fluid through the slit is related to the increasing ratio of the fluid through the inner flow channel to the fluid through the outer flow channel (since the resistance of the outer flow channel is constant) and vice versa. For example, if the inner filter portion 157 contains a flavorant (which may be released from the additive releasing component as described above with reference to the first embodiment), then the ratio corresponds to a particular flavor concentration. Thus, the scent can be set to one of three different concentrations by setting the selector 153 into one of three different open positions.

The advantage of the stepped arrangement of this embodiment over the tapered arrangement of the second embodiment is that the preferred gap size can be defined during manufacture and selected relatively easily by the user, that is to say without the need for precise control of the relative axial positions of the first and second selection means 154, 155. Preferred gap sizes may include, for example, very small gaps that are difficult for a user to select.

As mentioned above, the relative movement of the first and second selection means 154,155 may be angularly differentiated and/or limited. For example, the indexing and stop positions may correspond to a closed position and three different open positions.

The filter 150 may be attached to the tobacco rod by a cover layer (not shown) similar to that of the second embodiment.

Sixth embodiment

Fig. 13a and 13b show a part of a filter 201 according to a sixth embodiment of the invention. The filter 201 comprises a body filter portion 202, one end of which is to be attached to a tobacco rod (not shown) similar to the tobacco rod 12 of the first embodiment, and the other end of which is attached to a selector 203. The selector 203 comprises first and second selection devices 204, 205. As will be described in detail below, the second selection means 205 is attached to the body filter portion 202, while the first selection means 204 is movably attached to the second selection means 205. The tobacco rod, body filter portion 202, and first and second selection means 204,205 are generally cylindrical/cylindrical, have similar outer diameters, and are coaxially aligned, thereby defining an axis 206.

The words "near" and "far" are understood in the same manner as in the second embodiment.

The body filter portion 202 includes inner and outer filter portions 207,208 that define respective inner and outer flow channels. The inner and outer filter portions 207,208 are identical to the inner and outer filter portions 13,14 of the first embodiment, except that they need not include any additives. Instead, an additive release member 209 is provided within the second selection device 204, as will be described in more detail below.

An intermediate layer 210 is disposed between the inner and outer filter portions 207, 208. The intermediate layer 210 is the same as the barrier layer 19 of the first embodiment.

The inner filter portion 57 may have an additional plug wrap (not shown). The outer filter portion 58 may also have a plug wrap (not shown).

The first and second selection means 204,205 may be made of plastic or other suitable material.

As will become apparent, the first and second selection means 204,205 are movable relative to each other to firstly release additive from within the additive release member 209 and secondly adjustably open and close the inner flow passage.

The first selection device 204 includes an outer generally cylindrical sleeve portion 204a and an inner generally cylindrical solid portion 204 b. The axes of the portions 204a,204b are coincident with the axis 206. The portions 204a,204b are largely coextensive. An annular space 204c between the portions 204a,204b defines a flow path through the first selection device 204. The portions 204a,204b are connected to each other towards their proximal ends by spokes (not shown) similar to the spokes 54e of the second embodiment.

Second selection means 205 comprises an outer generally cylindrical sleeve portion 205a, and an inner generally cylindrical sleeve portion 205 b. The axes of the portions 205a, 205b are coincident with the axis 206. The outer portion 205a is shorter than the inner portion 205b and is centrally disposed with respect to the inner portion 205 b. Inner portion 205b separates second selection device 205 into inner and outer volumes 205c,205d, defining respective inner and outer flow channels. The portions 205a, 205b are connected to each other by a disc-shaped structure 205e at the distal end of the outer portion 205 a. Disc 205e is positioned perpendicular to axis 206. As will be described in greater detail below, the disc 205e is axially pierced with a plurality of holes 205 f.

The first and second selection means 204,205 are attached to each other by a threaded connection. The inner wall of the outer portion 204a of the first selection means 204 and the outer wall of the inner portion 205b of the second selection means 205 comprise cooperating threaded portions 204d, 205 g. Portion 204d is toward the middle of portion 204a, while portion 205g is toward the proximal end of portion 205 b. Thus, the smoker can control the relative axial position of the first and second selection means 204,205 by rotating one relative to the other. The threaded connection is adapted to allow fluid to pass through it. This may involve one or both of the portions 204d, 205g having an axially extending slit (not shown). The portions 204d, 205g can comprise cooperating portions (not shown) to index the rotation and thus the axial movement and/or to define a stop position corresponding to the maximum axial separation of the first and second selection means 204, 205. Alternatively, such indexing and/or stop positions may be otherwise defined or undefined.

A section of the distal end of the outer portion 204a of the first selection device 204 has a reduced outer diameter. Which fits within a section of the proximal end of the outer portion 205a of the second selection means 205. As shown, portion 205a can have an annular ridge 205h on its inner wall that engages the outer wall of portion 204a, and portion 204a can have an annular ridge 204e on its outer wall that engages the inner wall of portion 205 a. The ridges 204e, 205h serve to form a relatively low friction seal between the first and second selection means 204, 205. The seal serves to prevent air from being drawn into the first selection device 204 (or to limit the amount of such air). Alternatively, the ridges 204e, 205h can be omitted and such a seal formed directly between the inner and outer walls of the respective portions 204a, 205 a.

The inner portion 205b of the second selection means 205 extends axially from the distal side of the disc 205e in the form of a thin cylindrical tubular section. As shown, at this stage, the inner diameter of portion 205b may be constant, while the outer diameter of portion 205b, and therefore its wall thickness, decreases towards its distal end. Portion 205b is positioned between inner and outer filter portions 207,208 and intermediate layer 209 is positioned outside of portion 205 b. Alternatively, the outer diameter of portion 205b may be constant while the inner diameter decreases towards its distal end, and intermediate layer 209 may be positioned inside portion 205 b. In either case, this arrangement serves to hold second selection means 155 and body filter portion 152 together so as to form a seal that prevents the passage of additive between the inner and outer flow channels.

Some of the apertures 205f in the disc 205e connect the outer flow path defined by the outer filter portion 208 to the outer flow path defined by the exterior space 205d in the second selection means 205 and other apertures 205f connect the inner flow path defined by the inner filter portion 207 to the inner flow path defined by the interior space 205c in the second selection means 205.

The first and second selection means 204,205 are arranged such that they can cooperate with each other to firstly release the additive from the additive releasing member 209 and secondly adjustably open and close the inner flow path.

The inner portion 205b of the second selection means 205 and the disc 205e form a holder for the additive releasing member 209. As shown, component 209 may be in the form of a frangible capsule 209a containing liquid flavorant 209 b. Alternatively, other kinds of additive release means may be provided, such as those described elsewhere. As shown, a pair of annular ridges 205i can be provided on the inner wall of portion 205b to hold component 209 in place. A plurality of pin-like structures 205j extend axially from the proximal side of the disc 205e and are in contact with the feature 209.

Fig. 14a, 14b, 14c and 14d show the filter 201 in an initial position, a so-called release position, a closed position and an open position, respectively.

In the initial position (shown in fig. 13a and 14 a), the distal wall of the inner portion 204b of the first selection means 204 does not contact or contacts the part 209 light enough not to break it.

First and second selection means 154,155 can be moved closer together and the distal wall of portion 204b can force member 209 against pin 205 j. In the release position (as shown in fig. 14 b), the unbroken capsule 209a is pierced by the spike 205j and releases the flavourant 209 b. At least one aperture 205f in the disk 205j is aligned with the component 209 so that released scent 209b can flow into the inner filter portion 207.

The inner space 205c in the second selection means 205 has a tapered (conical) part towards its centre, wherein the taper is arranged such that the space 205c is wider at its proximal end. The inner portion 204b of the first selection device 204 is cylindrical.

In the closed position (as shown in fig. 14 c), a region of the inner portion 204b of the first selection means 204 is pressed against a region of the inner wall of the intermediate portion 205b of the second selection means 205. Thus, a section of space 205c is sealed and no fluid can flow from the inner flow path in second selection device 205 into the flow path in first selection device 204. The closed position may be the same as the release position, or the first and second selection means 204,205 may be closer together in the closed position than in the release position.

In the open position, in which the first and second selection devices 204,205 are further separated, there is a gap between the inner portion 204b of the first selection device 204 and the middle portion 205b of the second selection device 205. The gap allows fluid to pass from the inner flow path in second selection device 205 into the middle flow path in first selection device 204. The size of the gap increases with increasing axial separation of the first and second selection means 204, 205. Thus, the resistance of the fluid through the slit is reduced and thus the ratio of the fluid resistance through the inner flow channel compared to the fluid resistance through the outer flow channel is increased (because the resistance of the outer flow channel is constant). This ratio corresponds to a particular scent concentration after the scent 209b is released.

Thus, the smoker can control the release of the flavourant and then the intensity of the flavourant by the same action, i.e. by rotating the first and second selection means 204,205 relative to each other.

As mentioned above, the relative movement of the first and second selection means 204,205 may be angularly differentiated. The indexed positions may correspond to an initial position, a released position, a closed position, and one or more different open positions.

The filter 200 can be attached to the tobacco rod by a cover layer (not shown) similar to that of the second embodiment.

Variations of the second, third, fourth, fifth and sixth embodiments

Some variations of the filter according to the second, third, fourth, fifth and sixth embodiments will now be described.

The described embodiments may include features of any of the other embodiments. For example, any of the embodiments may use any of the arrangements described for holding the second selection means and the body filter portion together. In addition, any of the second, third, fourth and sixth embodiments may use the step arrangement of the fifth embodiment rather than the tapered arrangement for opening or closing the inner smoke passage, and vice versa.

Instead of spokes (e.g. the spokes 54e of the second embodiment), different parts of the first and second selection means can be connected to each other by other structures which allow fluid to pass through them. An example of such a structure is the perforated disc 205e of the sixth embodiment.

Instead of a threaded connection (e.g. the threaded portions 154f,155k of the fifth embodiment), the first and second selection means may be movably connected to each other in other suitable ways. Furthermore, the first selection means need not necessarily be rotated with respect to the second selection means. Instead, for example, the first selection device may simply slide toward or away from the second selection device. In this case, the first and second selection means can be connected to each other by means of a suitable sliding connection. Further, in this case, some or all of the cylindrical portions of the first and second selection means may have a cross section of a different shape, for example, a square.

Instead of the described mating portion, e.g. the tapered (conical) portion of the second embodiment, other suitable portions may be used to open or close the inner flow channel in the second selection means. Such portions may include different combinations of tapered portions, cylindrical portions, annular ridges, and the like.

Instead of overlapping regions (e.g. the portions with ridges 204e, 205h in the sixth embodiment) between the first and second selection means, other suitable ways may be used to establish a seal that prevents air from being sucked into the first selection means.

Instead of the arrangement described, other suitable means may be used to hold the second selection means and the body filter portion together and also to form a seal that prevents the passage of additive between the inner and outer flow channels.

Embodiments include specific mating features on the first and second selection devices, and/or features having specific orientations. However, where appropriate, the cooperating features may be provided on a different one of the first and second selection means and/or may have a different orientation.

Further variants

It should be appreciated that the foregoing exemplary embodiments should not be construed as limiting. Other variations and modifications will be apparent to persons skilled in the art upon reading the present application.

For example, in embodiments other than the sixth embodiment, the additive is contained within the inner flow passage in the body filter portion. Alternatively or additionally, the additive may be contained within the outer flow channel. In the fifth embodiment, additional additives may be included in the body filter portion 202. There may be one flow channel containing one additive and one flow channel containing a different additive. One flow channel may contain more than one additive, preferably in more than one additive release member. These additives may have a complementary effect or fragrance. Alternatively, none of the flow channels may contain an additive, and instead the flow channels may have different characteristics, related to, for example, the type of smoke being filtered or the amount of ventilation air being introduced.

Where the additive or one of the additives comprises activated carbon, it may be contained within the outer filter portion in the form of an activated carbon packet disposed on the inside of the outer plug wrap.

Instead of the smoke flow, one or both flow channels may be flow channels for the flow of scents only, for the flow of ventilation air only, or for the flow of scents and ventilation air only. These flow channels need not pass through the filter portion containing the filtering material.

There may be three or more flow channels. For example, there may be a plurality of grooved channels around the outer circumference of the non-fragranced filter portion. The channels may be separated from the non-fragranced filter portion by a corrugated barrier layer. The channels may contain additives, such as menthol flavors. A rotating portion at the end of the filter further from the tobacco rod may be provided to open or close the channel and thereby open or close the flow channel, for example so that smoke passes through a menthol environment.

The three or more flow channels may contain different additives or have different characteristics and may be individually selected.

The additive need not be contained within the additive-releasing member. In this case, the smoker need not first release the additive and can only use the selector to change the ratio of modified smoke.

The selector may be any selection device that allows fluid to selectively pass through the first and second flow paths.

As used herein, the terms "flavor" and "aroma" refer to materials that can be used to create a desired taste and aroma in a product for an adult consumer, as permitted by local regulations. They may include extracts (e.g. glycyrrhiza uralensis, hydrangea aspera, japanese white bark hackberry leaves, chamomile, fenugreek, clove, menthol, japanese mint, anise, cinnamon, herb vanilla, wintergreen oil, cherry, berry, sleeve, apple, liqueur, bourbon, scotch whisky, whiskey, spearmint, peppermint, lavender, cardamom, celery, balsam, bergamot, nutmeg, sandalwood, bergamot, geranium, honey essence, rose oil, vanilla, lemon oil, orange oil, cinnamon, caraway, brandy, jasmine, ylang, sage, fennel, allspice, ginger, anise, coriander, coffee, or mint oil obtained from any mint), flavour site enhancers, bitter taste acceptor site blockers, sensory acceptor site activators or mimetics, sugars and/or sugar substitutes (e.g. galactose, sugar alcohols, and/or sugar substitutes, Acesulfame potassium, aspartame, saccharin, cyclamate, lactose, sucrose, glucose, fructose, sorbitol, or mannitol), and other additives such as activated carbon, chlorophyll, minerals, botanicals, or breath fresheners. They may be imitation, synthetic or natural ingredients or mixtures thereof. They may be in any suitable form, for example oil, liquid or powder.

The additive release member may be a capsule having a housing, an interior cavity of which contains an additive fluid (liquid or powder). The housing of each additive release member is frangible to release all of the additive upon application of pressure.

The filter may comprise a reaction surface against which the additive release member can be pressed to facilitate release of the additive. In particular, the additive releasing member may be placed on the outer circumference of the filter. Radially adjacent filter material may provide a reaction surface against which the additive release member may be pressed. Preferably, the filtering material may be relatively hard (e.g., by including a relatively large amount of plasticizer) to form the reaction surface, and may have a hardness in excess of 90% Filterna value. The additive release member may be placed within the filtering material or within a cavity adjacent the filtering material. The cavity may be formed by an elongate inner rod of filter material surrounded by one or two annular outer portions of filter material. A cover layer forming the exterior of the filter is attached to the exterior of one or both filter materials and is spaced from the inner rod to define a cavity. Preferably, the inner rod is stiffer than the annular outer segments, optionally by comprising more plasticizer.

Alternatively, each additive release member may release its additive composition in a plurality of discrete doses, preferably activated by a plurality of separate pressure applications. Such an additive releasing member may comprise an elastically or plastically deformable housing, which is preferably designed to release the additive through cracks formed in predetermined areas. Alternatively, this type of additive-releasing member may comprise a porous absorbent matrix (e.g., an open cell foam material) having an open cell structure, in which the additive is contained. The substrate may be at least partially elastically deformable. The matrix is surrounded by a shell to hold additives, which may be frangible, elastically deformable, plastically deformable, or have a thin coating. The matrix may form a discontinuous additive-releasing means, or may be present in the first filter portion in an annular form. Alternatively, this type of additive-releasing member may comprise a porous matrix containing the additive in discrete cavities and having a closed-cell structure (e.g., a closed-cell foam) that is plastically deformable to release the additive.

The additive release member may be separately attached to the filter or the substrate. Alternatively, the additive release members may be connected by a mesh and may be connected by a laminated sheet strip of sheet material. Alternatively, the strip of sheet material may form the additive release member such that the additive release member does not have a separate housing and the strip of sheet material contains the additive.

The additive release component may be manually manipulated to release the additive, or the movable portion may be configured such that movement of the movable portion around the exterior of the smoking article releases the additive from the at least one additive release component. This movement is preferably a sliding or rotating movement by a ring or c-clip on the outer surface of the filter. The filter may provide a reaction surface against which the additive release member may be forced by the movable portion. The additive release member may be placed in one or more grooves extending circumferentially, longitudinally or helically. Alternatively, the movable portion comprises a cover layer defining two adjacent surfaces, wherein the additive release member is placed between the adjacent surfaces such that relative movement of the adjacent surfaces of the cover layer can release the additive from within the at least one additive release member.

The additive releasing member is preferably spherical. Alternatively, the additive release member may be elongate, having a longitudinal axis extending parallel to the longitudinal axis of the filter. The elongated additive release member preferably has a circular or elliptical cross-section and contains more additive than an additive release member of the same diameter. The elongate additive release member preferably has a maximum transverse width of less than 3.5mm, or less than 3mm, or from 2mm to 3 mm. Alternatively or additionally, the elongate additive release member may have a radial cross-sectional area that is less than 50% of the radial cross-sectional area of the smoking article, and optionally less than 40% or less than 30% of the radial cross-sectional area of the smoking article.

The additive release component is preferably separately located within the smoking article. Alternatively, the plurality of additive release members may be surrounded by an outer wall or outer wrap. The outer wrapper may be porous or configured to rupture or deform upon compression to allow release of the additive. The outer package may be contained in a further outer package. The additives may be contained within a plurality of discrete cavities within an open cell matrix or within a closed cell matrix. The open cell matrix and optionally the closed cell matrix have an outer wrap. One or more additive release members may be adhered to the exterior of a substantially larger additive release member. Alternatively, multiple additive release members having the same or different dimensions may be adhered together. Any of these embodiments may be considered to be multiple components connected into a unitary structure.

Embodiments of the present invention are configured to comply with applicable laws and/or regulations, such as, by way of non-limiting example, regulations relating to flavors, additives, emissions, ingredients, and/or the like. For example, the invention may be configured such that a smoking article embodying the invention complies with applicable legislation, both before and after adjustment by the smoker. These embodiments may be configured to comply with applicable regulations in all smoker-selectable locations. In some embodiments, the configuration is such that a smoking article embodying the invention meets or exceeds required regulatory tests, such as by way of non-limiting example, test thresholds/ceiling for cigarette emissions and/or smoke constituents, at all smokers selectable locations.

To address various problems and improve upon the prior art, the entire specification describes, by way of explanation, embodiments in which the claimed invention may be implemented and may provide superior filters for smoking articles. The advantages and features described in this specification are merely representative of embodiments and are not exhaustive and/or exclusive. They are used only to aid in understanding and teaching the claimed features. It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects of the present invention are not to be considered limitations on the invention as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilized and other modifications may be made without departing from the scope and/or spirit of the present invention. Various embodiments may suitably comprise, consist of, or consist essentially of various combinations of the disclosed elements, components, features, parts, steps, means, and the like. Additionally, the present invention includes other inventions not presently claimed, but which may be claimed in the future.

Claims (20)

1. A filter for a smoking article, the filter comprising: a first flow path through the filter; a second flow path through the filter, the first and second flow paths extending coaxially along the filter, the second flow path being disposed around the first flow path; a selector including a portion rotatable relative to the first and second flow passages to enable fluid to selectively pass through the first flow passage and to enable fluid to selectively pass through the second flow passage, wherein a cylindrical first filter portion and a hollow cylindrical second filter portion surrounding the first filter portion define the first and second flow passages, respectively; and wherein: or an extension of the first filter portion is received in a recess of the selector, wherein the recess narrows towards an end wall of the recess; or the extension of the second filter portion forms a recess receiving the tubular portion of the selector, wherein the tubular portion widens towards its end at the opening of the recess.

2. The filter of claim 1, wherein the selector includes a portion that is movable relative to the first and second flow passages to allow selection.

3. A filter according to any one of the preceding claims, wherein the first and second flow channels extend coaxially along the filter and the first flow channel is disposed within the second flow channel.

4. A filter according to claim 1, wherein the selector comprises a projection on the end wall of the recess extending into and engaging the first filter portion and/or at least one further projection on the side wall of the recess, wherein the further projections are arranged to allow movement of the first filter portion towards the end wall of the recess and thereafter prevent movement in the opposite direction during assembly.

5. A filter according to claim 4, wherein the projection is arranged to deform the first filter portion so that it engages with a side wall of the recess.

6. A filter according to claim 4 or 5, wherein a layer is arranged between the first and second filter portions and extends with the first filter portion into the recess.

7. A filter according to claim 4 or 5, wherein the selector comprises:

a first selector portion substantially fixed relative to the first and second filter portions; and

a second selector part which is rotatable and/or axially movable relative to the first selector part.

8. A filter according to claim 7 wherein:

the first selector portion having a first set of one or more windows aligned with the first filter portion and a second set of one or more windows aligned with the second filter portion; and is

The second selector part is rotatable relative to the first selector part and has a third set of one or more windows which may be aligned with the first set of windows to select the first flow path, or may be aligned with the second set of windows to select the second flow path, or may be partially aligned with the first and second sets of windows to partially select the first and second flow paths.

9. A filter according to claim 7 wherein:

the first selector portion having a selector first flow passage in communication with the first flow passage defined by the first filter portion and a selector second flow passage in communication with the second flow passage defined by the second filter portion; and is

The second selector portion is axially movable relative to the first selector portion and has a portion arranged to open or close a segment of the selector first flow passage in the first selector portion in dependence on the axial displacement.

10. A filter according to claim 9, wherein the portion and/or the section arranged to open or close a section of the selector first flow channels in the first selector part in dependence on the axial displacement has a conical shape.

11. A filter according to claim 9, wherein:

the portion arranged to open or close a section of the selector first flow passage in the first selector part in dependence on the axial displacement has a constant outer diameter;

the section comprising two or more constant diameter portions separated by one or more steps; and is

The portion arranged to open or close a section of the selector first flow passage in the first selector part in dependence on the axial displacement is movable into a selected one of the constant diameter portions to allow selection of one of two or more discrete levels of flow through the first flow passage.

12. A filter according to any one of claims 9 to 11, comprising a threaded connection between the first and second selector portions to allow for varying axial displacement by rotational force.

13. A filter according to any one of claims 4,5 and 8 to 11, wherein at least one flow channel comprises an additive.

14. A filter according to claim 13, comprising an additive release member arranged to release additive in response to deformation and/or rupture.

15. A filter according to claim 14, wherein the selector comprises a portion movable relative to the first and second flow channels to allow the rotation, and wherein the additive release member is deformable and/or breakable under the action of movement of the portion of the selector.

16. A filter according to claim 14 or 15, wherein the additive release member is included in the selector.

17. A filter according to claim 11, wherein at least one flow channel contains an additive, the filter comprising an additive release member arranged to release the additive in response to deformation and/or rupture, the additive release member being comprised in the selector, and the portion of the second selector part arranged to open or close a segment of the selector first flow channel in the first selector part in dependence on the axial displacement is further arranged to press the additive release member against a portion of the first selector part in order to release the additive.

18. A filter according to claim 17, wherein the portion of the first selector part comprises one or more projections arranged to cause preferential release of additive into the first filter part.

19. A filter according to any one of claims 4,5,8 to 11,14 to 15, 17 and 18, comprising an additive release element disposed in the first flow path.

20. A filter for a smoking article, the filter comprising: a first flow path through the filter; a second flow path through the filter, the first and second flow paths extending coaxially along the filter, the second flow path being disposed around the first flow path; and a portion rotatable relative to the first and second flow passages to allow fluid to selectively pass through the first and second flow passages, wherein the cylindrical first filter portion and the hollow cylindrical second filter portion surrounding the first filter portion define the first and second flow passages, respectively; and wherein: or an extension of the first filter portion is received in a recess of the selector, wherein the recess narrows towards an end wall of the recess; or the extension of the second filter portion forms a recess receiving the tubular portion of the selector, wherein the tubular portion widens towards its end at the opening of the recess.