WO2012076496A1

WO2012076496A1 - Method and apparatus for introducing objects into a continuous flow of material

Info

Publication number: WO2012076496A1
Application number: PCT/EP2011/071848
Authority: WO
Inventors: Diego Ferrazzin; Michele Pagnoni
Original assignee: Philip Morris Products S.A.
Priority date: 2010-12-07
Filing date: 2011-12-06
Publication date: 2012-06-14

Abstract

An apparatus for introducing objects into a continuous flow of material comprises: a reservoir (1) for providing a plurality of objects to be introduced into the continuous flow of material; a transfer wheel (3) for transporting the objects to a means for inserting the objects into the continuous flow of material, the transfer wheel (3) further comprising a peripheral surface (30); a transfer zone (31) extending about a portion of a peripheral surface (30) of the transfer wheel (3); delivery means (2) for moving the objects from the reservoir (1) to the transfer zone (31), and means (32) for moving the objects through the transfer zone (31); wherein the delivery means (2) and the transfer zone (31) are configured such that the objects are moved from the reservoir (1) to the transfer zone (31) and through the transfer zone (31) along a single line path.

Description

Method and apparatus for introducing objects into a continuous flow of material

The present invention relates to a method and to an apparatus for introducing objects into a continuous flow of material. For example, the objects may be beads or capsules which are to be introduced into a continuous flow of filter material during manufacture of the filter component of a smoking article.

Smoking articles, for example cigarettes, typically have a rod-shaped structure and include a charge, roll or column of smokable material such as cut tobacco. The cut tobacco is typically surrounded by a paper wrapper thereby forming a so-called "tobacco rod". In filter cigarettes a cylindrical filter element is aligned in an end-to-end relationship with the tobacco rod. By way of example, a filter element may comprise cellulose acetate tow filter material. The tow may be circumscribed by a paper material known as "plug wrap". The filter element is typically attached to one end of the tobacco rod using a circumscribing wrapping material known as "tipping paper".

Various proposed methods for modifying the sensory attributes of smoke involve using filter elements as vehicles for adding additional flavour to the mainstream smoke in the smoking article. For example, it has been suggested to introduce objects such as beads or capsules into the filter material during manufacture of the filter elements.

Various methods and apparatuses have been suggested for the introduction of such objects into the filter material during manufacture of the filter elements for smoking articles. One such apparatus for the introduction of objects into the continuous flow of material is described in WO-A-2010/055120. The prior art apparatus comprises a reservoir containing the objects. The reservoir opens out into a transfer chamber in which the objects are circulated. The objects circulating in the transfer chamber move along the peripheral surface of a rotatable transfer wheel. The transfer wheel has pockets in its peripheral surface, and the objects are introduced into and retained in the pockets with the aid of suction. By rotation of the transfer wheel the objects are transported to a location where they are released from the transfer wheel and introduced into the continuous flow of material.

There is an ongoing need in the mass manufacture of filters to manufacture such filters as efficient and reliable as possible.

According to the present invention there is provided a method and an apparatus for introducing objects into a continuous flow of material. While in the following

specification only embodiments are illustrated in which objects are inserted into filter material, the invention also comprises cases in which the objects are inserted into other parts of the smoking article, for example into the tobacco rod or into a cavity in the filter. The apparatus according to the invention comprises a reservoir for providing a plurality of objects to be introduced into the continuous flow of material and a transfer wheel for transporting the objects to a means for inserting the objects into the continuous flow of material. The transfer wheel comprises a peripheral surface, and a transfer zone extends about a portion of this peripheral surface of the transfer wheel. The apparatus further comprises delivery means for moving the objects from the reservoir to the transfer zone, and means for moving the objects through the transfer zone. The delivery means and the transfer zone are configured such that the objects are moved from the reservoir to the transfer zone and through the transfer zone along a single line path.

A "single line path" in this respect denotes a continuous path along which the objects can move or can be moved only one after another. By way of example, the single line path can be embodied as a channel the dimensions of which are chosen relative to the dimensions of the objects such that the objects can move or can be moved through the channel only one after another. Thus, the objects can be moved from the reservoir along the single line path to and through the transfer zone extending about the outer peripheral surface of the transfer wheel. In the transfer zone a number of objects which are moved through the transfer zone are transferred onto the transfer wheel. The transfer wheel transports these objects to the location where they are introduced into the filter material by any suitable means. The movement of the objects along the single line path enables a particular high speed of operation of the apparatus while at the same time the reliability of having the objects transferred onto the transfer wheel is increased. Also, the forces acting on the respective objects are reduced so that crushing of objects is prevented. This is particularly relevant for breakable capsules that contain a flavourant inside.

In one particular embodiment of the apparatus according to the invention the delivery means for moving the objects from the reservoir to the transfer zone comprises Venturi means that are arranged at an exit of the reservoir. The Venturi means comprise accelerating means for speeding up the objects exiting the reservoir and guiding means for directing the objects into a delivery channel which is configured to only allow movement of the objects through the delivery channel along the single line path. In one embodiment, the guiding means may comprise a narrowing wall portion having tapering side-walls that lead into the delivery channel. Preferably, the accelerating means comprise at least one nozzle for applying an overpressure air flow along the travel path of the objects exiting the reservoir. This creates a negative pressure in the reservoir, sucking the objects into the delivery channel . Thus, the objects exiting the reservoir are accelerated and safely guided into the delivery channel at high speed. A further embodiment of the apparatus according to the invention further comprises a vibration element. The vibration element is arranged to extend into a space defined by the tapering side-walls of the narrowing wall portion in a manner such that the vibration element allows only one object at a time to pass and to enter the delivery channel. This embodiment further improves the process of singularizing the objects at the exit of the reservoir where the narrowing wall portion is arranged and where the objects leave the reservoir to enter the delivery channel. By way of example, the vibration element can be a vibrating pin or plate, but any other suitable vibration element is also

conceivable.

In a further embodiment of the apparatus according to the invention, the means for moving the objects through the transfer zone comprise suction means for generating a negative pressure causing the objects in the transfer zone to move towards the peripheral surface of the transfer wheel. Suction means, for example suction channel openings, are reliable means for assisting in moving the objects through the transfer zone and transferring them onto the peripheral surface of the transfer wheel. By way of example, pockets may be provided in the peripheral surface of the transfer wheel, as this is described in the afore-mentioned WO-A-2010/055120. In this case, the suction also assists in retaining the objects in the pockets of the transfer wheel where they are transported to the location where they are released from the transfer wheel and introduced into the filter material.

A further embodiment of the apparatus according to the invention comprises a return channel extending from an exit of the transfer zone to an upper region of the reservoir, and means for moving surplus objects through the return channel into the upper region of the reservoir. Preferably, the transfer wheel comprises circumferentially spaced apart pockets for the objects on the peripheral surface. The objects moved through the transfer zone along the single line path are partly transferred onto the pockets of the transfer wheel with high reliability. The objects in the single line path that are between the pockets in the transfer zone are not transferred onto the transfer wheel. These not transferred "surplus" objects are moved through the return channel. Preferably, the return channel comprises also a single line path, back to the upper region of the reservoir where the objects enter the reservoir again. Entering the reservoir in the upper region of the reservoir is advantageous in that there is no back pressure caused by objects contained in the reservoir. This is particularly so as long as the level of the objects contained in the reservoir is below the location where the return channel opens out into the reservoir in the upper region of the reservoir and the location of the return channel is selected to allow for a sufficient size of the reservoir. In one embodiment of the apparatus, the means for moving the objects through the return channel may comprise at least one nozzle for applying an overpressure air flow to the objects in order to return the objects into the upper region of the reservoir.

In yet a further embodiment of the apparatus according to the invention, the delivery means comprise at least one additional Venturi means being arranged at the exit of the reservoir and a corresponding at least one additional delivery channel which is configured to be opened and closed selectively. The delivery means further comprises at least one sensor, and the at least one sensor is associated with each delivery channel for detecting clogging of the respective delivery channel and for initiating the selective opening of the at least one additional delivery channel. This embodiment is particularly advantageous in that it provides for redundancy thus increasing the availability of the apparatus. In case the actual delivery channel gets clogged, the respective sensor detects that this delivery channel is clogged and initiates that another delivery channel is opened, so that production of filter elements can be continued without interruption even in case a delivery channel gets clogged. By way of example, the sensor detecting that the actual delivery channel is clogged may send a corresponding signal to a control device which then causes that another delivery channel is opened. Alternatively or in addition, the additional delivery channel may be used to clean or otherwise service the other delivery channel.

Further advantageous aspects of the invention become apparent from the following description of embodiments of the invention with the aid of the drawings in which:

Fig. 1 shows the essential parts of a first embodiment of the apparatus according to the invention,

Fig. 2 shows an embodiment of the Venturi zone of the embodiment of the apparatus shown in Fig. 1 ,

Fig. 3 shows an embodiment of the delivery channel leading from the reservoir to the transfer zone of the embodiment of the apparatus shown in Fig. 1 ,

Fig. 4 shows an embodiment of the return channel leading from the

transfer zone to the upper region of the reservoir of the embodiment of the apparatus shown in Fig. 1 ,

Fig. 5 shows the essential parts of a further embodiment of the apparatus according to the invention comprising an additional Venturi means. Essential parts of an embodiment of the apparatus according to the invention are shown in Fig. 1. These parts comprise a reservoir 1 for providing a plurality of objects which are to be introduced into a continuous flow of material. The filter material can be supplied from a source (not shown) such as a storage bale, bobbin or the like in form of a continuous strand of filter material. The continuous strand of filter material is drawn through the apparatus, and the individual objects are introduced at a predetermined location into the filter material. This can be performed in a manner known in the art, for example in the manner described in the afore-mentioned WO-A-2010/055120 (see Figs. 6-12 and the corresponding parts of the specification of WO-A-2010/055120), the disclosure of which is incorporated herein by reference.

The apparatus further comprises delivery means 2 comprising Venturi means 20 and a delivery channel 21. The Venturi means 20 are arranged at the exit of the reservoir 1 and comprise accelerating means in the form of a nozzle 200 and guiding means comprising a narrowing wall portion having tapering side-walls 201. The nozzle 200 speeds up the objects exiting the reservoir 1 , for example beads or capsules, by blowing overpressure air at the objects or past the objects along their travel path to have them enter the delivery channel 21. The tapering side-walls guide the objects into the delivery channel 21. The delivery channel 21 leads from the reservoir 1 to a transfer zone 31 and opens out tangentially into the transfer zone 31. The transfer zone extends about a portion of the peripheral surface 30 of a transfer wheel 3.

In the delivery channel 21 the objects are moved one after another along a single line path to the transfer zone 31. The dimensions of the delivery channel 21 are chosen such that only one object after another can be moved through the delivery channel 21. A sensor 22 may be provided to monitor clogging of the delivery channel 21 and to generate a corresponding signal in case the delivery channel 21 gets clogged.

In order to improve singularizing of the objects exiting the reservoir 1 a vibration element 10, for example a vibration blade, is provided. The vibration element 10 is arranged to extend into the space defined by the tapering side-walls 201 of the narrowing wall portion, as is shown enlarged in Fig. 2. The vibration element 10 allows the objects (for example beads) to pass only one after another, thus improving singularizing of the objects. The excitation for vibration element 10 can either be branched-off of the excitation of the chassis of the reservoir 1 which may have an electric vibration means (not shown) to vibrate the reservoir 1 in order to move the objects towards the tapering side-walls 201 and into the delivery channel 21. Alternatively, the vibration element 10 can be excited by a separate excitation means. Once an object has passed the vibration element 10, the object enters the delivery channel 21 and is accelerated by the pressurized air from nozzle 200 so that the object is moved along the single line path through the delivery channel 21 to the transfer zone 31. Additional nozzles may be provided for sorting the objects and for further improving acceleration of the objects on entry into the delivery channel 21.

The transfer zone 31 which extends about the peripheral surface 30 of the transfer wheel 3 is also dimensioned such that the objects can be moved through the transfer zone 31 only one after another along a single line path. In the transfer zone 31 , the objects are transported with the aid of a suitable air flow which is provided by a number of nozzles 32 with the aid of which either an overpressure air flow or a suction air flow is generated to move the objects through the transfer zone 31. Some of the objects are transferred onto the peripheral surface 30 of the transfer wheel 3. the transfer is assisted with suction means. The suction means comprise suction channels 4 for providing a negative pressure acting on the peripheral surface 30 of the transfer wheel 3 to attract the objects moving through the transfer zone 31. The transfer wheel 3 may be embodied similar to that described in detail in WO-A-2010/055120 and may comprise pockets (not shown) in its peripheral surface 30, with the negative pressure being applied to these pockets. Thus, the objects are sucked into the respective pockets in the peripheral surface 30 of the transfer wheel 3 where they are retained until the respective pocket has been rotated to the location where the object is released and introduced into the filter material. The way of sucking the objects into the pockets provided in the peripheral surface 30 of the transfer wheel 3 with the aid of negative pressure is known for example from the afore-mentioned WO-A-2010/055120. The way of releasing an object from the pocket once the transfer wheel has rotated the respective pocket to the location where the object is introduced into the filter material, is also known and is described in detail, for example, in the afore-mentioned WO-A-2010/055120 (see in particular Figs. 3,5,6-12, and the corresponding parts of the specification), the disclosure of which is incorporated herein by reference.

As mentioned already, only some but not all of the objects moved through the transfer zone 31 along the single line path are transferred to the peripheral surface 30 (for example into the pockets, see above) of the transfer wheel 3. To make sure that each pocket of the transfer wheel 3 contains an object, for example a bead or a breakable capsule, a number of objects higher than the number of pockets provided in the peripheral surface 30 of the transfer wheel is moved through the transfer zone 31.Preferably the speed of the objects moved through the transfer zone 31 is similar to the speed of the transfer wheel 3.

The surplus objects, that is those objects which are moved through the transfer zone 31 but are not transferred into the pockets are returned into the reservoir 1. For that purpose, a return channel 5 is provided (see Fig. 4). The return channel 5 extends from the exit of the transfer zone 31 to an upper region of the reservoir 1. The entry of the return channel 5 into the reservoir 1 is arranged above the level of the objects contained in the reservoir 1. When compared to the apparatus disclosed in WO-A-2010/055120 the introduction of objects into the transfer zone and the transport of objects out of the transfer zone is separated whereas the in the apparatus disclosed in WO-A-2010/005120 the objects are circulated within the transfer zone.

In order to return the objects to the upper region of the reservoir 1 through the return channel 5, at least one nozzle 50 is provided for applying an overpressure air flow to the objects. The overpressure airflow moves the objects towards the upper region of the reservoir 1 through the return channel 5. The return channel is dimensioned to allow the transport of the surplus objects in a single line path.

A further embodiment of the apparatus according to the invention is shown in Fig. 5. According to this embodiment at least one additional Venturi means 60 is provided. The at least one additional Venturi means 60 comprises a nozzle 600 as well as tapering side- walls 601 which are arranged at the exit of the reservoir 1. Further, in this embodiment at least one additional delivery channel 61 is provided. The at least one additional delivery channel 61 can be selectively opened and closed. Also, an additional vibration blade 1 1 is provided assisting in the singularizing of the objects as the objects exit the reservoir 1.

While only one additional Venturi means is shown in Fig. 5, more then one additional Venturi means may be provided as well. Also, at least one additional sensor 62 is provided. The additional Venturi means 60 and the additional delivery channel 61 provide for redundancy. When the delivery of objects is interrupted due to clogging of the delivery channel 21 , the sensor 22 detects that delivery channel 21 is clogged, a corresponding signal is generated to initiate that the additional delivery channel 61 is opened. A control unit (not shown) receives the signal from the sensor 22 indicating that delivery channel 21 is clogged, selectively activates the additional Venturi means 60 and opens the additional delivery channel 61 so that production can continue without interruption. The more additional Venturi means and delivery channels are provided, the higher the availability of the apparatus and the lower the risk that production must be interrupted due to clogging of a delivery channel.

While specific embodiments of the apparatus have been described with the aid of the drawings, it is obvious for the person skilled in the art that many changes and modifications are conceivable without departing from the spirit of the present invention.

Claims

1. A method for introducing objects into a continuous flow of material, comprising the steps of:

providing a reservoir (1) containing the objects to be introduced into the continuous flow of material;

moving the objects along a single line path from the reservoir (1) to a transfer zone (31) extending about a portion of a peripheral surface (30) of a transfer wheel (3) and through the transfer zone (31);

transferring the objects onto the peripheral surface (31) of the transfer wheel (3); transporting the objects by the transfer wheel (3) to a location where the objects are introduced into the continuous flow of material,

wherein moving the objects along a single line path from the reservoir (1) to the transfer zone (31) comprises providing a Venturi zone at an exit of the reservoir (1) for accelerating the objects exiting the reservoir (1) and for having them enter a delivery channel (21) leading to the transfer zone (31), the delivery channel (21) being configured to only allow movement of the objects through the delivery channel (21) along the single line path.

A method according to claim 1 , further comprising the step of providing a vibration element (10) in the Venturi zone, the vibration element (10) being arranged and configured to allow only one object at a time to pass and to enter the delivery channel (21).

A method according to any one of claims 1 or 2, further comprising the step of in the Venturi zone applying an overpressure air flow to the objects for accelerating the objects and for having the objects enter the delivery channel (21).

4. A method according to any one of the preceding claims, further comprising the step of returning objects, that have moved through the transfer zone (31) and that have not been transferred onto the transfer wheel, into an upper region of the reservoir (1).

A method according to claim 4, wherein returning the objects comprises providing a return channel (5) leading into the upper region of the reservoir (1) and applying an overpressure air flow to the objects for moving them through the return channel (5) into the upper region of the reservoir (1).

A method according to any one of the preceding claims, further comprising providing at least one additional Venturi zone and a corresponding at least one additional delivery channel (61) capable of being opened and closed selectively, and further comprising providing means (22) for detecting clogging of a respective delivery channel (21)and for initiating the selective opening of the at least one additional delivery channel (61).

An apparatus for introducing objects into a continuous flow of material, comprising: a reservoir (1) for providing a plurality of objects to be introduced into the continuous flow of material;

a transfer wheel (3) for transporting the objects to a means for inserting the objects into the continuous flow of material, the transfer wheel (3) further comprising a peripheral surface (30);

a transfer zone (31) extending about a portion of a peripheral surface (30) of the transfer wheel (3);

delivery means (2) for moving the objects from the reservoir (1) to the transfer zone (31), and

means (32) for moving the objects through the transfer zone (31);

wherein the delivery means (2) and the transfer zone (31) are configured such that the objects are moved from the reservoir (1) to the transfer zone (31) and through the transfer zone (31) along a single line path.

Apparatus according to claim 7, wherein the delivery means comprise Venturi means (20) being arranged at an exit of the reservoir (1), the Venturi means (20) comprising accelerating means for speeding up the objects exiting the reservoir (1) and guiding means for directing the objects into a delivery channel (21) which is configured to only allow movement of the objects through the delivery channel (21) along the single line path.

Apparatus according to claim 8, wherein the guiding means comprise a narrowing wall portion having tapering side-walls (201) leading into the delivery channel (21), and wherein the accelerating means comprise at least one nozzle (200) for applying an overpressure air flow to the objects exiting the reservoir (1).

Apparatus according to claim 9, further comprising a vibration element (10), which is arranged to extend into a space defined by the tapering side-walls (201) of the narrowing wall portion in a manner such that the vibration element (21) allows only one object at a time to pass and to enter the delivery channel (21).

1 1. Apparatus according to any one of claims 7 to 10, wherein the means for moving the objects through the transfer zone (31) comprise suction means (4, 32) for generating a negative pressure causing the objects in the transfer zone (31) to move towards the peripheral surface (30) of the transfer wheel (3).

12. Apparatus according to any one of claims 7 to 11 , further comprising a return channel (5) extending from an exit of the transfer zone to an upper region of the reservoir (1), and means for moving surplus objects through the return channel (5) into the upper region of the reservoir (1) , where these surplus objects have not been transferred in the transfer zone (31).

13. Apparatus according to claim 12, wherein the means for moving the objects

through the return channel (5) comprise at least one nozzle (50) for applying an overpressure air flow to the objects in order to return the objects into the upper region of the reservoir (1).

14. Apparatus according to any one of claims 7 to 13, wherein the delivery means comprise at least one additional Venturi means (60) being arranged at the exit of the reservoir (1) and a corresponding at least one additional delivery channel (61) which is configured to be opened and closed selectively, wherein the delivery means further comprises at least one sensor (22), where the at least one sensor is associated with each delivery channel (21) for detecting clogging of the respective delivery channel (21) and for initiating the selective opening of the at least one additional delivery channel (61).