WO2015162408A1

WO2015162408A1 - Adhesive applicator

Info

Publication number: WO2015162408A1
Application number: PCT/GB2015/051118
Authority: WO
Inventors: Kie Seon PARK
Original assignee: British American Tobacco (Investments) Limited
Priority date: 2014-04-24
Filing date: 2015-04-14
Publication date: 2015-10-29
Also published as: GB201407242D0

Abstract

An adhesive applicator (1) for applying adhesive to a tensioned web of tipping paper (7) as it moves through a smoking article filter assembly unit is disclosed. The adhesive applicator comprises a transfer roller (4) configured to transfer adhesive from an adhesive reservoir (3) onto a surface of a moving web of tipping paper (7) in contact with said transfer roller (4) as the transfer roller rotates, and a suction roller (11). The suction roller (11) is configured to enable a region of low pressure to be generated that is operable to suck a web of tipping paper (7) against the suction roller (11) to move the web as the suction roller rotates. A method of applying adhesive to a tensioned web of tipping paper (7) moving through a smoking article filter assembly unit is also disclosed.

Description

Adhesive Applicator

Technical Field

This invention relates to an applicator for applying adhesive to a moving web of tipping paper in an apparatus used to form smoking articles such as filter cigarettes. The invention also relates to a smoking article filter assembly apparatus incorporating the adhesive applicator of the invention and to a method of applying adhesive to a tensioned web of tipping paper moving through a smoking article filter assembly unit using the adhesive applicator of the invention.

Background

Apparatus used in the assembly of smoking articles, such as filter cigarettes, includes a filter attachment unit for attaching a filter and a tobacco rod to each other to form a filter cigarette. A double length filter rod may be aligned with two tobacco rods, one at either end of the filter rod, and the three rods are wrapped with a patch of wrapping material known as a 'tipping paper' to join them together. The centrally positioned double length filter rod is then cut into two to form two filter cigarettes. The patch is attached to the filter and tobacco rod using adhesive applied to sections, or to the entire surface, of a web of tipping paper by an adhesive applicator prior to the web being cut into patches.

Summary of the Invention

In accordance with an embodiment of the invention, there is provided an adhesive applicator for applying adhesive to a tensioned web of tipping paper as it moves through a smoking article filter assembly unit, comprising a transfer roller configured to transfer adhesive from an adhesive reservoir onto a surface of a moving web of tipping paper in contact with said transfer roller as the transfer roller rotates, and a suction roller, the suction roller being configured to enable a region of low pressure to be generated that is operable to suck a web of tipping paper against the suction roller to move the web as the suction roller rotates.

The suction roller preferably comprises a curved surface and a plurality of openings that extend through said surface that are spaced from each other around the circumference of the curved surface. A suction chamber may be formed within the suction roller and the openings may be in communication with the suction chamber.

The suction chamber is preferably connectable to a vacuum source for generating said region of low pressure in said suction chamber and through said openings.

In some embodiments, a blocking member is received in the suction chamber and the suction roller rotates relative to the blocking member so that the blocking member obstructs openings passing over the blocking member as the suction roller rotates to prevent low pressure being generated through said obstructed openings.

The adhesive applicator preferably comprises a motor to rotatably drive the suction roller and a control unit operable to control the speed of the motor. In a preferred embodiment, a control unit operable to control a suction force generated by the low pressure region is provided.

According to another aspect of the invention, there is provided a smoking article filter assembly apparatus comprising the adhesive applicator according to the invention.

The smoking article filter assembly apparatus may comprise a cutter for cutting the web and a controller that is operable to control the suction roller in dependence on the cutter. The controller may be operable to control the speed of rotation of the suction roller and/or the suction force through the suction roller.

According to another aspect of the invention, there is provided a method of applying adhesive to a tensioned web of tipping paper moving through a smoking article filter assembly unit using an adhesive applicator comprising a transfer roller configured to transfer adhesive from an adhesive reservoir onto a surface of a moving web of tipping paper in contact with said transfer roller as the transfer roller rotates, the method including the step of generating a region of low pressure operable to suck a web of tipping paper against a suction roller so that the web moves as the suction roller rotates.

Brief Description of the Drawings Embodiments of the invention will now be described, by way of example only, with reference to Figures 4 and 5 of the accompanying drawings, in which:

Figure 1 shows a schematic side elevation of a known adhesive applicator in an operational position with a web of tipping paper passing through it;

Figure 2 shows the same side elevational view of the adhesive applicator of Figure 1 but in a non-operational position;

Figure 3 shows a perspective view of an actual adhesive applicator without a tipping paper web passing through it;

Figure 4 shows a schematic side elevation of an adhesive applicator and tipping paper web according to an embodiment of the invention; and

Figure 5 shows a schematic side elevation of the suction roller shown in Figure 4.

Detailed Description

As used herein, the term 'smoking article' includes smokeable products such as cigarettes, cigars and cigarillos whether based on tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco or tobacco substitutes and also heat-not-burn products. Whilst not all smoking articles have a filter, embodiments of the present invention relate to smoking articles that are provided with a filter for the gaseous flow drawn by the smoker and which is attached to a tobacco rod in a cigarette filter assembly apparatus using tipping paper.

A known adhesive applicator 1 forming part of a cigarette filter assembly apparatus (not shown) is illustrated in Figures 1 to 3. The adhesive applicator 1 includes a trough 2 containing a reservoir 3 of adhesive and a transfer roller 4 which is mounted to a frame 5 for rotation about an axis 'A' above the trough 2 and has a circumferential surface 6 projecting into reservoir of adhesive 3 received in the trough 2. During operation, a layer of adhesive is received on the circumferential surface 6 of the transfer roller 4 and is deposited on the underside surface 7a of a tensioned web of tipping paper 7 which is moving across the transfer roller 4 as it rotates. The path of the tipping paper web 7 through the adhesive applicator 1 is indicated by arrow 'W in Figure 1.

A web guide roller 8 is positioned to either side of the transfer roller 4. Each web guide roller 8 is rotatably mounted to a lower end of a respective arm 9 and each arm 9 is pivotally mounted to the frame 5 for rotation about an axis 'B', so that they can each pivot to move the web guide rollers 8 between an operational and a non-operational position under pneumatic control and in response to a signal from a filter assembly apparatus control unit (not shown).

In an operational position, as shown in Figure 1, the web guide rollers 8 are pivoted into a downward position about axis 'B' to alter the path of the tensioned web and force the underside surface 7a of the tensioned tipping paper web 7 into contact with the surface 6 of the transfer roller 4, so that adhesive is transferred from the rotating transfer roller 4 to the underside surface 7a of the moving web 7 in the region of contact between the web 7 and the transfer roller 4. The web guide rollers 8 rotate freely relative to their arms 9 to minimise friction between the circumferential surface 8a of each web guide roller 9 and the upper surface 7b of the web 7 as the web 7 passes beneath the web guide rollers 9 and over the transfer roller 4 situated between them.

When the filter assembly unit is stopped and the web 7 is stationary, the arms 9 pivot into an upward position about axis 'B', as shown in Figure 2. Due to the tension in the web 7, the web raises out of contact with the transfer roller 4. It is necessary for the web 7 to come out of contact with the transfer roller 4 because, if the web 7 remained in contact with the transfer roller 4 when stationary, it would quickly become saturated with the adhesive present on the transfer roller 4 causing the web 7 to break during subsequent processing through the filter assembly unit.

An embodiment of the invention is shown in schematic form in Figure 4, from which it can be seen that the adhesive applicator 1 includes a suction roller 10 located downstream of the transfer roller 4 so that the web 7 passes over the transfer roller 4 before passing beneath and around the suction roller 10. The web guide rollers 8 and control arms 9 have been omitted from Figure 4. Whilst it is envisaged that the suction roller 10 will be employed with the adhesive applicator 1 described with reference to Figures 1 to 3, it will be appreciated that its use is not limited as such and it may also be used with adhesive applicators having a different configuration to that shown in Figures 1 to 3.

The suction roller 10 is rotatably driven by a motor and has a circumferentially extending curved outer surface 11 which is provided with openings 12 that are spaced evenly around the curved outer surface 11. The openings 12 communicate with a suction chamber 13 within the suction roller 10. The suction chamber 13 is connectable to a vacuum source (not shown) in order to generate a low pressure region within the suction chamber 13 and through the openings 12. A controller (not shown) is used to enable the strength of the suction force to be controlled so that the web 7 is sucked against the circumferential surface 11 of the suction roller 10. As the suction roller 10 rotates, it pulls or draws the web 7 over the transfer roller 4 and through the adhesive applicator 1. Whilst it is envisaged that the openings are spread uniformly around the curved outer surface 11 of the suction roller 10, in other embodiments they may be spread in non-uniform pattern, they may be grouped together in separate arrays, or the openings may be spaced in some other way. Whilst the tension in the web 7 and its rate of movement through the adhesive applicator 1 can be controlled by controlling the speed of rotation of the suction roller 10, it is also possible to control the tension and rate of movement of the web 7 by varying the strength of the suction force. When a relatively high suction force is used, the web 7 will not move relative to the suction roller 10 and so it will be drawn through the adhesive applicator 1 at a rate which is dependent solely on the speed of rotation of the suction roller 10. However, if the suction force is reduced below a certain amount, a degree of slippage may occur between the suction roller 10 and the web 7 which can be used to control the rate of movement of the web 7 through the adhesive applicator 1 and isolate that part of the web 7 upstream from the suction roller 10, relative to a part of the web 7 downstream of the suction roller 10, from any fluctuations in tension that may occur in the downstream part which may be caused by, for example, cutting of the web in subsequent process step in the smoking article filter assembly apparatus. The smoking article filter assembly apparatus can include a web cutter and a controller operable to control the degree of slippage of the web 7 over the suction roller 10 and/ or the speed of the suction roller 10 in dependence on the operation of the web cutter to ensure that the web is cut accurately and consistently as the web 7 passes through the apparatus.

As shown in Figure 5, the suction roller 10 may contain a stationary blocking element 14 which blocks some of the openings 12 for part of the rotation of the suction roller 10 so that there is no suction through the openings 12 that lie directly over the blocking element 14. For example, the blocking element 14 may block those openings 12 over a region where the web 7 and the suction roller 10 are not in contact with each other. By eliminating the low pressure at a point at which the web 7 breaks contact with the suction roller 10, the web 7 will be released from the surface 11 of the suction roller 10 more cleanly and freely than if it had to be pulled off the suction roller 10 against the suction force which would tend to keep it against the suction roller 10. The blocking element 14 may be made of a ceramic material.

In order to address various issues and advance the art, the entirety of this disclosure shows by way of illustration various embodiments in which the claimed invention(s) may be practiced and provide for a superior adhesive applicator. The advantages and features of the disclosure are of a representative sample of embodiments only, and are not exhaustive and/ or exclusive. They are presented only to assist in understanding and teach the claimed features. It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects of the disclosure are not to be considered limitations on the disclosure as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilised and

modifications may be made without departing from the scope and/or spirit of the disclosure. Various embodiments may suitably comprise, consist of, or consist essentially of, various combinations of the disclosed elements, components, features, parts, steps, means, etc. In addition, the disclosure includes other inventions not presently claimed, but which may be claimed in future.

Claims

1. An adhesive applicator for applying adhesive to a tensioned web of tipping paper as it moves through a smoking article filter assembly unit, comprising a transfer roller configured to transfer adhesive from an adhesive reservoir onto a surface of a moving web of tipping paper in contact with said transfer roller as the transfer roller rotates, and a suction roller, the suction roller being configured to enable a region of low pressure to be generated that is operable to suck a web of tipping paper against the suction roller to move the web as the suction roller rotates.

2. An adhesive applicator according to claim l, wherein the suction roller comprises a curved surface and a plurality of openings that extend through said surface spaced from each other around the circumference of the curved surface.

3. An adhesive applicator according to claim 2, comprising a suction chamber formed within said suction roller, said openings being in communication with said suction chamber.

4. An adhesive applicator according to claim 3, wherein said suction chamber is connectable to a vacuum source for generating said region of low pressure in said suction chamber and through said openings.

5. An adhesive applicator according to claim 3 or 4, comprising a blocking member received in the suction chamber, the suction roller rotating relative to the blocking member so that the blocking member obstructs openings passing over the blocking member as the suction roller rotates to prevent low pressure being generated through said obstructed openings.

6. An adhesive applicator according to any preceding claim, comprising a motor to rotatably drive the suction roller and a control unit operable to control the speed of the motor.

7. An adhesive applicator according to any preceding claim, comprising a control unit operable to control a suction force generated by the low pressure region.

8. A smoking article filter assembly apparatus comprising the adhesive applicator according to any preceding claim.

9. A smoking article filter assembly apparatus according to claim 8, comprising a cutter for cutting the web and a controller, the controller being operable to control the suction roller in dependence on the cutter.

10. A smoking article filter assembly apparatus according to clam 9, wherein the controller is operable to control the speed of rotation of the suction roller and/or the suction force through the suction roller.

11. A method of applying adhesive to a tensioned web of tipping paper moving through a smoking article filter assembly unit using an adhesive applicator comprising a transfer roller configured to transfer adhesive from an adhesive reservoir onto a surface of a moving web of tipping paper in contact with said transfer roller as the transfer roller rotates, the method including the step of generating a region of low pressure operable to suck a web of tipping paper against a suction roller so that the web moves as the suction roller rotates.

12. An adhesive applicator substantially as hereinbefore described, with reference to the accompanying drawings.