Abstract:
A machine for making filter rods for use in the manufacture of smoking articles comprises a garniture configured to receive filter plug material and filter wrapping material and to form a wrapped elongate filter rod, the garniture comprising a tongue; the maker further comprises a rotatable object-transport member arranged to receive objects from an object store and to deliver said objects directly into the tongue such that the objects are inserted into filter plug material passing through the tongue and a cutter configured to cut the elongate filter rod, thereby forming filter rod segments having one or more objects therein.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to a machine for making filter rods for use in the manufacture of smoking articles such as filtered cigarettes. The machine is configured to insert objects into the filter rods. 
       BACKGROUND OF THE INVENTION 
       [0002]    Filter rods used in the manufacture of filtered cigarettes conventionally comprise a plug of cellulose acetate tow wrapped with a paper plugwrap. Known filter rod making machines comprise a garniture which receives a flow of tow and a ribbon of filter paper and forms a paper wrapped elongate filter rod, which is subsequently cut into filter rod segments. The garniture usually has a tongue which compresses the filter tow as it passes therethrough. This type of filter making machine and in particular the garniture and tongue elements are well known per se to those skilled in the art. 
         [0003]    EP1833316 describes a machine configured to provide filter media, in particular granular material or pre-measured capsules, into filter material during filter rod manufacture. The machine of EP1833316 has a suction dome which sucks filter media into a plurality of spaced apart pockets formed in the circular face of a rotating pocket wheel. Rotation of the pocket wheel positions the pockets filled with filter media in register with the inlet of an air transport tube. Once aligned, vacuum is released and air pressure applied through a perforated pocket “bottom” to expel the media into the transport tube. The tube is arranged to enter the tongue of the machine so that when the filter media exits the discharge end of the tube it passes into the centre of the filter rod being formed. Subsequently, the rod is wrapped with paper. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention provides an alternative approach to inserting objects into filter rod material during filter rod manufacture. 
         [0005]    The invention provides a machine for making filter rods for use in the manufacture of smoking articles, comprising a garniture configured to receive filter plug material and filter wrapping material and to form a wrapped elongate filter rod, the garniture comprising a tongue configured so that filter plug material is compressed as it passes therethrough; the filter maker further comprises a rotatable object-transport member arranged to receive objects from an object store and to deliver said objects directly into the tongue such that the objects are inserted into filter plug material passing through the tongue, and a cutter configured to cut the elongate filter rod, thereby forming filter rod segments having one or more objects therein. 
         [0006]    In this way, the objects are delivered into the tongue of the garniture directly, without intermediary. Thus mechanical complexity of the maker is minimised. 
         [0007]    Further, the filter plug material follows a steady, controlled path through the tongue and thereafter and thus the position and/or spacing of the objects in the eventual rod can be precisely controlled by placing the objects in appropriate positions of the filter plug material passing through the tongue. 
         [0008]    Preferably, the filter plug material undergoes compression in the tongue such that the filter plug material presses against the objects so as to secure them in position in the filter plug material passing through the tongue. In this way, unwanted positional variation from object to object is minimised. 
         [0009]    Preferably, the filter plug material is cellulose acetate tow. 
         [0010]    Preferably, the objects are inserted into the tow in the tongue such that the objects in the wrapped elongate filter rod are evenly spaced. Further preferably, the objects are inserted into the tow in the tongue such that the one or more objects are axially centred within the eventual filter rods. 
         [0011]    The objects are preferably frangible fluid-containing capsules, but other objects such as pellets, strands, beads or any combination of pellets, strands, beads and capsules may alternatively or in addition be inserted. The capsule diameter is preferably within the range 2-6 mm. 
         [0012]    The rotatable object-transport member preferably penetrates into the tongue such that each object received by the rotatable object transfer member exits the object-transport member at an exit point inside the tongue. 
         [0013]    The rotatable object-transport member is preferably a rotatable wheel having a plurality of recesses arranged around the rim thereof. 
         [0014]    Preferably the machine has a stuffer jet configured to compress the tow before it enters the garniture. Advantageously, the stuffer jet allows a more uniform density of tow to be achieved and enables manufacture of filters with different densities/pressure drops. 
         [0015]    The machine may have a first body part comprising a first tongue part and a second body part comprising the object-transport member and a second tongue part, and a hinge arranged so that the relative position of the first and second body parts can be adjusted between a first position in which the first and second tongue parts are separated so that the interior of the tongue is accessible for cleaning and tow threading and a second position in which the first and second tongue parts are aligned so that tow can pass from one to the other. 
         [0016]    In order that the invention may be more fully understood embodiments thereof will now be described by way of example with reference to the accompanying drawings in which: 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a cross sectional view of a filter rod making machine. 
           [0018]      FIG. 2  is a perspective view of the machine in its operative (in use) position. 
           [0019]      FIG. 3  is a perspective view of the machine in a position in which the upper body of the machine is raised relative to the lower body. 
           [0020]      FIG. 4  is a perspective view of the upper body and shows an exploded view of the inlet tongue section. 
           [0021]      FIG. 5  shows the inlet tongue section. 
           [0022]      FIG. 6  is a cross sectional view showing the capsule transport wheel positioned in the inlet tongue section. 
           [0023]      FIG. 7  is a perspective view of a part of the lower body of the machine. 
           [0024]      FIG. 8  is an exploded perspective of the view of  FIG. 7 . 
           [0025]      FIG. 9  shows the plough of the inlet tongue section. 
           [0026]      FIG. 10  shows filter rods. 
           [0027]      FIG. 11  shows alternative ploughs. 
           [0028]      FIG. 12  shows an alternative transport wheel. 
           [0029]      FIG. 13  shows the stuffer jet of the machine. 
       
    
    
     DETAILED DESCRIPTION 
       [0030]      FIGS. 1 and 2  show part of a filter rod making machine  1 . In operation, filter plug material in the form of cellulose acetate filter tow is drawn from a source, stretched in a set of stretching rollers (not shown) and compressed through stuffer jet  3  and through the tongue  4  of garniture  5 . As shown, the machine  1  has a rotatable capsule transport wheel  6  arranged to deliver frangible flavourant-containing capsules from circumferential recesses  6   a  directly into the tongue so that the capsules come into contact with filter tow passing therethrough. The tow is paper wrapped in the garniture to form an elongate rod which is then cut to form filter rod segments, each of which contains a desired number of capsules, for example one, two, three or four. 
         [0031]    The filter rod segments can be subsequently used in cigarette manufacture to make cigarettes having one or more capsules in the cigarette filter. In one exemplary cigarette manufacturing process, a filter rod segment containing two capsules is axially aligned with two paper wrapped tobacco rods positioned at opposing ends of the filter rod. A wrapper, known as a tipping paper, is then wrapped around the tobacco rods and filter rod to join them together. The wrapped filter rod is then transversely cut through its centre, between the two capsules, thereby forming a pair of filtered cigarettes, each having a capsule in its filter. 
         [0032]    Each frangible capsule is preferably substantially spherical, formed from gelatin and contains a flavourant, for example menthol, spearmint, orange essence, mint, liquorice, eucalyptus, one or more of a variety of fruit flavours or any mixture of flavourants. By applying pressure to the outside of the filter the capsule can be ruptured, thereby releasing the flavourant, which acts to flavour the smoke drawn through the filter of the cigarette. 
         [0033]    Turning now to a more detailed description of the machine  1 , as shown in  FIGS. 1 and 2 , the transport wheel  6  is vertically orientated and rotatably mounted to the body  7  of the machine  1  on a shaft. The wheel  6  has a disk section  8  and a front section  9  bolted to the disk section  6 . The disk section  8  is arranged between a capsule hopper  10  and the tongue  4  and is configured to sequentially transfer capsules therebetween. 
         [0034]    The tongue  4  of the garniture  5  is tapered along its length so as to radially compress the filter tow as it passes through the tongue  4 . Tow compression in the tongue is the final tow compression stage of the rod making process. 
         [0035]    An opening is formed in the top of the tongue  4 , the opening being wide enough to receive the disk section  8  of the transport wheel  6 , which penetrates into the tongue  4  through the opening as shown in  FIG. 1 . 
         [0036]    As the wheel  6  rotates, capsules fall under gravity from the hopper  10  into the plurality of capsule-receiving recesses  6   a  arranged circumferentially around the rim of the disk section  8 , as shown in  FIG. 1 . The clockwise rotating wheel  6  carries the capsules through the opening in the top of the tongue and into the tongue interior, where the capsules exit the wheel  6  and pass into the filter rod being formed. As shown in  FIG. 2 , housing  7   a  is provided around the rim of disk section  8  to prevent capsules from falling from the wheel  6 . 
         [0037]    Thus, the capsules are delivered directly into the tongue of the garniture, where the path of the tow is steady and controlled, remaining so until the rod is formed. 
         [0038]    Furthermore, since the capsules are inserted during compression of the tow, the tow is compressed around the capsules and thus secures them in position. Accordingly, the position and spacing of the objects in the eventual rod depends only on the position that the objects are placed in the tow passing through the tongue. Thus, the present machine allows the position of the capsules to be precisely controlled, with little variation from capsule to capsule or from filter to filter. This is desirable because consumers may perceive variations in capsule position negatively and may for example consider filters having off-centre capsules to be defective. Preferably, the capsules are positioned in the tow so as to be axially aligned and centered within the eventual rod. 
         [0039]    The capsules exiting the wheel  6  may drop under gravity from the recesses  6   a  of the wheel  6  into the tow passing through the tongue  4 . Alternatively, the transport wheel  6  may have a capsule ejection mechanism, for example an air-jet propulsion mechanism, configured to sequentially eject the capsules from the recesses in the rim section  8  and into the tow passing through the tongue  4 . The transport wheel may alternatively, or in addition comprise a suction pump configured to apply suction to the capsules to hold them in position in the recesses before ejection. 
         [0040]    As shown in  FIGS. 2 and 3 , the machine  1  has a hinge mechanism which allows part of the tongue  4  to be lifted away from the machine  1 . This facilitates threading of the tow from the stuffer jet  3  through the tongue  4  prior to machine start-up, and also allows convenient cleaning of the interior of the tongue  4 . 
         [0041]    The hinge mechanism comprises a hinge  11  connected to upper body  12  and lower body  13  of the machine  1 , and a lifting cylinder  14  passing through a bore  15  in the lower body and attached to the bottom of the distal end of the upper body  12 . 
         [0042]    The hinge  11  is arranged so that upper body  12  of machine  1  can pivot upwards with respect to lower body  13  from the operative position shown in  FIG. 2  to the lifted position shown in  FIG. 3 , and vice versa. In the operative position the upper body  12  rests on the lower body  13  and the outlet of the stuffer jet  3  is in register with the tongue entrance  4  as shown in  FIG. 2 . In the lifted position shown in  FIG. 3  an inlet portion  16  of the tongue is positioned clear of the stuffer jet so that an operator can access the tongue interior for convenient cleaning and tow threading. The machine can be selectively positioned in either position by raising or lowering the lifting cylinder  14 , which is preferably hydraulically actuated. 
         [0043]    Referring to  FIG. 4 , upper body  12  comprises hopper  10 , transport wheel  6  and inlet tongue portion  16 , which is shown in exploded perspective view. As shown in  FIGS. 4 ,  5  and  6 , inlet tongue portion  16  comprises left and right sidewalls  17 ,  18 , a plough  19  and a shoe  20 . The plough  19  and shoe  20  are positioned at opposite ends of the inlet tongue portion  16  and between the sidewalls  17 ,  18 , with a gap between the shoe  20  and plough  19 . As shown, sidewalls  17  and  18  and plough  19  have extending upwardly attachment parts that have threaded holes in register with one another through which a set of bolts is threaded to hold the sidewalls  17 ,  18  and plough  19  together at one end of the inlet tongue portion  16 . As shown in  FIG. 5  the shoe  20  is bolted between and to the sidewalls  17 ,  18  at the opposing end of the tongue portion  16 . As shown, the sidewalls  17 ,  18  and plough  19  define an inlet tube  21  at the input end of the inlet tongue portion  16 , through which tow enters the tongue  4 , and an outlet  22  through which tow exits the inlet tongue portion  16 . Referring to  FIG. 5(   b ), which shows a bottom view, the bottom of the inlet tongue portion  16  has an elongate opening  23  extending from the outlet  22  along the bottom of the inlet tongue portion  16  to the inlet tube  21 . 
         [0044]    As shown in  FIG. 5(   a ), left and right sidewalls  17 ,  18  define an opening  24  in the top of inlet tongue portion  16  into which the wheel  6  penetrates, as shown in  FIG. 6 . As shown, the plough  19  and shoe  20  have arcuate surfaces  25 ,  26  facing the wheel  6  and arranged so that in operation, the wheel  6  rotates in close proximity to the surfaces  25  and  26 . The surface  25  of the plough  19  prevents capsules from unintentionally falling from the clockwise rotating wheel  6  while the surface  26  of the shoe acts to scrape off any tow which becomes attached to the wheel  6  so as to prevent tow from being carried by the wheel out of the opening  24 . As shown in 
         [0045]      FIG. 5(   d ), a gap  27  is defined between the bottom end of surface  25  and the bottom end of surface  26 , and the bottom end of surface  25  is lower than the bottom end of surface  26 . 
         [0046]    As shown in  FIGS. 2 and 3 , stuffer jet  3  (which can also be referred to as a “transport jet”) is mounted to the lower body  13  and is arranged to deliver tow directly into the inlet tube  21  of the tongue  4 . Advantageously, the stuffer jet  3  allows a more uniform density of tow to be achieved in the eventual filters and enables filter manufacture with selected densities/pressure drops. The stuffer jet  3  is shown in more detail in  FIG. 13 . The length L of the body of the stuffer jet is preferably between 100 mm and 120 mm is further preferably 107.5 mm. 
         [0047]    As shown in  FIGS. 3 ,  7  and  8 , lower body  13  has a garniture inlet channel  28  which tapers from the upstream to the downstream end thereof. In operation, the garniture tape runs along the floor of the channel  28  and a ribbon of plugwrap paper in frictional contact with the garniture tape is dragged through the channel  28  on top of the tape and is thereby drawn from a bobbin (not shown) along a series of rollers and into the garniture. The feature of a garniture tape in the garniture to progressively wrap plugwrap paper around the filter tow to form a filter rod is well known per se in the art and will not be described in detail herein. 
         [0048]    As shown in  FIGS. 2 and 3  the inlet tongue portion  16  is adapted to fit into and cover the channel  28  in the operative position shown in  FIG. 2 . In operation, tow passes through the inlet tube  21  and onto the moving paper ribbon in the channel  28  via the elongate opening  23  in the bottom of the inlet tongue portion  16 . The tow is then dragged along the channel  28  by frictional contact with the paper ribbon. 
         [0049]    Referring to  FIG. 3 , tongue  4  further comprises a fixed tongue portion  29  positioned just downstream of the inlet tongue portion  16 . In use, tow in the channel  28  passes from through the outlet  22  of the inlet tongue portion  16  directly into the fixed tongue section  29 . As shown, the inlet and fixed tongue sections  16 ,  29  are both tapered so that a continuous tapering is obtained along the length of the tongue  4  to compress the tow as it passes through. 
         [0050]    The fixed tongue section  29  is shown in more detail in  FIGS. 7 and 8 . As shown, the fixed tongue section  29  is formed as a tapered half-pipe, mounted in a tapered channel  30  formed in the lower body  13 . In the operative position, channel  28  is integral with channel  30  and the inlet tongue portion  16  is aligned with the inlet of the fixed tongue section  29 . 
         [0051]    As shown in  FIGS. 7 and 8 , fixed tongue section  29  is held in place in channel  30  by a mounting assembly  31 , which comprises first, second and third mounting brackets  32 ,  33 ,  34 . As shown, mounting bracket  32  is integrally formed with the top of tongue section  29  and bolted to mounting bracket  34 . Mounting bracket  33  is bolted to mounting bracket  34  and to the lower body  13  of the machine  1 , thereby fixing the fixed tongue section  29  in position. 
         [0052]    The plough  19  of tongue  4  is shown in more detail in  FIG. 9 . As shown, the plough  19  has an attachment part  35  and a tow separating edge  36  oppositely disposed to the arcuate surface  25 . In operation, tow passing through the tongue  4  comes into contact with tow separating edge  36 , which separates the tow into two tow streams on either side of the plough  19 . In this way, a furrow is created in the tow, into which capsules are received from the wheel  6 . This furrow extends beyond the length of the plough  19 , up to a point where the movement of the tow flow causes the furrow to close. During capsule delivery, capsules are carried in the recesses  6   a  of wheel  6  through the opening  24  and to an exit point, where they exit the wheel and pass through the gap  27  between the plough and shoe and into furrow in the tow. The furrow subsequently closes around the capsules which are carried with the tow through the remainder of the garniture. The paper is subsequently fully wrapped around the tow by the action of the garniture to form an elongate paper wrapped rod, which is subsequently cut to form individual filter rods segments. 
         [0053]      FIG. 10  illustrates different filter rods  37 ,  38 ,  39 , which may be produced using the machine  1 . As shown, each rod includes one or more evenly spaced gelatin capsules  40  surrounded by a plug of cellulose acetate tow  41 , the tow being wrapped with a paper wrapper  42 . The first, second and third rods  37 ,  38 ,  39  respectively comprise one, two and four capsules. The second rod  38  is twice as long as the first rod  37  and the third rod  39  is twice as long as the second rod  38 . The skilled person will appreciate that many different rod configuration having different lengths and different numbers of capsules could be produced by the machine  1 . 
         [0054]      FIG. 11(   a ) illustrates an alternative plough  43   a  to the plough  19  which has a capsule guide  44   a  arranged to receive capsules from the wheel  6  and to guide the capsules into the furrow. The capsule guide  44   a  assists in positioning the capsules so that once the rod is fully formed, the capsules are axially centred and axially aligned with one another. As shown, the capsule guide  44   a  is shaped so as to direct the capsules exiting the guide in a direction substantially parallel to the direction of movement of the tow. In this way, impact forces on the capsule are minimised, thus preventing capsule damage. Further, since the capsules do not have a substantial vertical velocity component, vertical deflection due to elastic interaction with the tow is minimised.  FIG. 11(   b ) illustrates a further alternative plough  43 ( b ) having an alternative capsule guide  44 ( b ). 
         [0055]    Many other modifications and variations will be evident to those skilled in the art. For example, although the machine  1  has been described as inserting frangible fluid-containing capsules into filter rods, other objects such as pellets, strands, beads or any combination of pellets, strands, beads and capsules could alternatively or in addition be inserted. 
         [0056]    Furthermore, the filter rods may be suitable for use in the manufacture of any smoking article, including cigarettes cigars and cigarillos whether based on tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco or tobacco substitutes and also heat-not-burn products. 
         [0057]      FIG. 12  shows an alternative transport wheel  45 . As shown, transport wheel  45  has a front section  46 , a delivery drum  47  and a clamp plate  48 . As shown a dowel pin  49  connects front section  46  to delivery drum  47 . Clamp plate  48  is urged against delivery drum  47  by clamp screw  50 , which is bolted to front section  46 . The transport wheel  45  can be conveniently disassembled by removing clamp screw  50 , thereby allowing easy cleaning of the components. Furthermore, the dowl pin  49  may be used as a marker to identify the angular position of the wheel  45  in relation to the shaft. Thus, before removing the wheel  45  for cleaning, an operator can record the rotational position so that the wheel can be loaded back onto the shaft in the same rotational position after cleaning. 
         [0058]    The hopper  10  may include a deflector or roller arranged to carry the weight of some of the capsules in the hopper, so that capsules do not become crushed therein. The hopper  10  may further comprise a vibrating plate to agitate the capsules, to facilitate transfer into the wheel  6 . An air jet unit may be mounted in the hopper  10  to assist capsule movement. The wheel  6  may comprise raised notches to further agitate the capsules in the hopper. 
         [0059]    Further, although the capsule-receiving recesses are preferably arranged evenly around the circumference of the wheel  6 ,  45  so that an even separation is achieved between capsules in the elongate filter rod, alternatively the capsule-receiving recesses may be arranged according to a different pattern to provide different spacings between different capsule pairs in the elongate filter rod. 
         [0060]    For example, the capsule-receiving recesses  6   a  may be arranged so that the separation between a first pair of capsules is 24 mm while the separation between a neighbouring pair of capsules is 12 mm. A filter rod  51  produced by a machine having capsule-receiving recess arranged in this way is illustrated in  FIG. 10(   d ). The separation between capsules in capsule pair  52  is 24 mm and the separation between capsules in neighbouring capsule pair  53  is 12 mm. The filter rod  51  is 108 mm long. The separation between the edge of the rod  51  and the first capsule is 6 mm. 
         [0061]    Many other modifications and variations will be evident to those skilled in the art, that fall within the scope of the following claims: