United States Patent [191 Van Hall 1 Mar. 26, 1974 APPARATUS FOR OBTAINING ROUNDED Primary Examiner-R0y Lake FILTER PLUGS FOR CIGARETTES [75] Inventor: Floyd Van Hall, Durham, NC.
[73] Assignee: Liggett & Myers Incorporated, New
York, N.Y.
[22] Filed: Dec. 4, 1972 [21] Appl. No.: 311,565
[52] U.S. Cl. 93/1 C, 131/94 [51] Int. Cl B30b 3/02 [58] Field of Search 93/1 C, 1 G, 1 WZ, 77 FT, 93/83; 131/94 [56] References Cited UNITED STATES PATENTS 2,857,722 lO/l958 Smith 131/94 UX 3,164,243 1 H1965 Rudszinat et a1. 93/1 C 2,809,640 10/1957 Oldenkamp 131/94 Reilly, Carr 8!. Chapin [5 7] ABSTRACT The filter plug roller is formed by a pressure applying rotating roller and a holder having two inserts. The roller and inserts define a passageway for the filter plugs in which the first insert is more closely spaced to the roller than is the second insert so as to cause deformation of the filter plugs during rolling of the plugs over the first insert. The second insert is spaced from the roller at a distance equal to the diameter of the filter plug so as to cause a gentle rolling of the filter plugs out of the apparatus. The first insert serves to deform the relatively stiff papers used in enveloping the filter media of the filter plug while the second insert serves to impart a substantially perfect roundness to the filter plug.
16 Claims, 7 Drawing Figures PAIENIEDums mm 3799 041 sum 1 or 2 APPARATUS FOR OBTAINING ROUNDED FILTER PLUGS FOR CIGARETTES This invention relates to an apparatus and method for obtaining rounded filter plugs for cigarettes.
Heretofore, in the manufacture of filter cigarettes made of a filter and a tobacco column, it has been known to manufacture the filter separately from the tobacco column. Generally, the filters have been made in the form of a filter plug of a length to supply filters for six or more cigarettes. Such filter plugs have, in turn, been made from a continuous rod of filter material which is served into the composite filter plug lengths. ln forming such a filter rod, the filter media has been enveloped in a travelling strip of paper, commonly referred to as mouthpiece or filter paper. This paper has usually been delivered in a flat condition to receive the filter media and has thereafter been folded over the filter media with a seam being formed on the overlapping edges of the paper by various techniques. In many cases, during the formation of the seam, the filter plug has been deformed, for example, into an oblong crosssectional shape due to the forces required for seaming. As a result, the resultant filter plugs have also been of a deformed shape.
Since a deformed filter plug is usually not suitable for application to a tobacco column of round shape for the manufacture of a filter cigarette, the filter plugs have been subjected to various rounding techniques. For example, it has been known to pass the filter plugs individually through a confined path in which the filter plugs can be rolled into a round shape. For such a purpose, it has been known to use a plug roller formed of a press roller and abed plate-like structure having a curvilinear surface conforming to the shape of the roller and spaced a distance from the roller equal to the diameter of the filter plug. Such a structure serves to receive and roll the filter plug between the roller and plate-like structure so as to smooth out the deformed shape of the filter plug into a rounded cross-sectional shape.
However, in the case where a filter for a filter cigarette is made of multi-filter media, for example, where a granular adsorptive filter material such as charcoal has been sandwiched between two sections of fibrous entrainment filter material such as cellulose acetate, the filter plugs for which these filters are made have not been adequately rounded in the conventional plug rollers. This has been found to be caused, in part, by the use of one layer of plug wrap paper for enveloping the fibrous filter media sections and the use of a second layer of mouthpiece paper for enveloping both the wrapped fibrous filter media sections and the granular filter media sections. In addition, the stiffness of the papers has been such as to resist the deformation forces of the plug roller so that the filter plug does not respond to the rolling action imparted by the plug roller.
Accordingly, it is an object of this invention to provide a technique of rounding filter plugs made with relatively still paper.
It is another object of this invention to provide a technique of rounding multi-filter media filter plugs for cigarettes.
It is another object of this invention to provide a plug roller of simple construction for rounding filter plugs in an economical fashion.
It is another object of this invention to provide a technique of rounding filter plugs made with multiple layers of paper.
Briefly, the invention provides an apparatus and method for rounding filter plugs for cigarettes. The apparatus is constructed with a pressure applying means having an endless movable surface, a first surface means having a friction surface spaced a first distance from the pressure applying means of a magnitude less than the diameter of a filter plug to cause a deformation of the filter plug during rolling on the friction surface, and a second surface means having a friction surface spaced a second distance from the pressure applying means of greater magnitude than the first distance and of a magnitude equal to the diameter of a filter plug to cause rolling of the filter plug. The pressure applying means serves as a drive to move the delivered filter plugs over the respective surfaces of the two friction surface means. In addition, the narrower spacing between the pressure supplying means and the first surface means allows the filter plug to be positively deformed so as to overcome the resistance of the filter papers of the plug to deformation while at the same time removing any residual forces in the filter plug which would cause a return to the deformed state. For example, the distance between the first surface means and the pressure applying means can be 1/16 inch less than the nominal diameter of the filter plug. The distance between the second surface means and the pressure applying means permits the deformed filter plug to expand under its normal resiliency while being gently rolled into a truly round cross-sectional shape.
In one particular embodiment of the invention, the pressure applying means is in the form of a pressure roller having a resiliently deformable rubber cover thereon while the two surface means are in the form of insert members which are placed within a holder and which are each provided with a roughened curvilinear frictional surface, for example, a serrated surface.
In order to provide a smooth transition between the insert members, the surface of the first insert member is provided with an arcuately curved forward or first portion and a tapered tail or second portion while the surface of the second insert member is formed with an arcuate portion contiguous to the tapered surface of the first insert member. Also, the tapered surface-of the first insert member terminates at a point slightly higher than the initial point of the second insert member while providing a continuous surface therewith. In addition, the curvilinear surface of the two insert members are each formed on a radius corresponding to the radius of the roller.
The method of the invention resides in the step of moving a formed filter plug through a passageway having a first portion sized of a magnitude less than the diameter of the formed filter plug to cause deformation and rolling of the filter plug through the first portion, and a second portion sized of a magnitude greater than the first portion and equal to the diameter of the formed filter plug to cause rolling of the filter plug through the second portion.
These and other objects and advantages of the invention will become more apparent from the following de tailed description and appended claims taken in conjunction with the accompanying drawings in which:
FIG. 1 illustrates a schematic view of a machine for making multi-filter media filter plugs;
FIG. 2 illustrates a fragmentary view of a portion of a filter rod within the machine of FIG. 1;
FIG. 3 illustrates a view taken on line 33 of FIG.
FIG. 4 illustrates an exaggerated cross-sectional view of a filter plug made on a machine as shown in FIG. 1;
FIG. 5 illustrates a cross-sectional view of an apparatus according to the invention;
FIG. 6 illustrates a view taken on line 66 of FIG. 5; and
FIG. 7 illustrates a cross-sectional view ofa filter plug which has been rounded by the apparatus as shown in FIGS. 5 and 6.
Referring to FIG. 1, a machine 10 for making filter plugs 11 is of generally known construction and includes a conveyor system 12 for receiving a supply of fibrous filter media 13, such as tow, from a source at one end, a tube 14 for gathering and forming the tow into a cylinder and a supply means 15 for supplying a continuous strip of plug wrap paper 16 for enveloping the tow to form a plug rod 18. In addition, a suitable means is provided to fold the longitudinal edges of the plug wrap paper 16 about the tow cylinder and a seam sealer 17 is provided to overlap and seal the longitudinal edges of the plug wrap paper 16 to form a longitudinal seam. The machine 10 also includes a knife assembly 19 which serves to sever the plug rod 18 into sequential spaced apart plugs 20 and a conveyor system 21 downstream of the knife assembly 19 to receive and convey the individual plugs 20 on a travelling web 22 of mouthpiece paper supplied from a supply means 23. This mouthpiece paper 22 can be of lighter weight and thinner thickness than the plug wrap paper 16. As shown, the mouthpiece paper 22 is'delivered from a supply roll 23 over a plurality of suitable guide rolls 24 and is positioned on the conveyor 21 so as to convey the filter plugs 20 under a granulated filter media dispensing apparatus 25 as is known. In addition, a garniture section (not shown) is provided in which the mouthpiece paper 22 is sequentially formed into a U- shape to receive the granulated filter material and thereafter enveloped over the filter plugs 20 are granulated filter media 26 in a tube-like cylinder with overlapping edges 27 (see FIG. 3).
Referring to FIGS. 1 and 3, a seam sealer 28 of generally known construction is positioned downstream of the dispensing apparatus 25 to seal the overlapping edges 27 of the mouthpiece paper 22 to each other. For example, the seam sealer 28 includes a heater bar 29 which is mounted over the travelling assembly of mouthpiece paper 22 and filter media. This seam sealer 28 applies heat and pressure to the mouthpiece paper 22 in the area of the overlapped edges 27 to effect a longitudinal seam seal and to form a continuous filter rod 30. A suitable guide (not shown) can also be pro vided to shape the conveyor ribbon 31 into a rounded shape to act as a backup for the heater bar 29.
Referring to FIG. 1, the filter rod is conveyed to a single knife cutter 32 which is timed to sever the filter rod 30 into equal lengths of filter plugs 11, each made up of a multisectional construction (see FIG. 2), for example, to provide two or more filters. These filter plugs 11 are then pushed by the plugs behind as well as by the rod 30 through a heat sealing apparatus 33, for example, as described in US. Pat. application Ser. No. 268,816 filed July 3, I972.
Referring to FIG. 5, after the plugs 11 leave the heat sealing apparatus 33, each is deposited onto a ramp 34 which is downwardly inclined so as to deliver each plug 11 to a plug roller 35.
Referring to FIG. 4, as a filter plug 11 passes out of the machine 10, the plug 11 may have a deformed shape from a rounded, i.e. circular, cross-sectional shape. For purposes of exaggeration, the filter plug 11 is shown with an oblong shape with the longitudinal seam shown flattened.
Referring to FIGS. 5 and 6, the plug roller 35 includes a rotatable roller 36 provided with a resiliently deformable rubber cover 37 and a holder 38 below the roller 36 which has a recess 39 receiving a pair of insert members 40, 41.
Referring to FIG. 6, the roller 36 is fixedly mounted on a shaft 42 which carries a pulley 43 at one end so as to be driven in a suitable manner by a drive source (not shown). The shaft 42 is journalled within suitable anti-friction bearings 44 near each end which bearings 44 are mounted within upstanding legs 45 secured to the holder 38 so as to fix the roller 36 in a preset position.
Referring to FIG. 5, the inserts 40, 41 which can be of any suitable material such as steel or other metal are each provided with a frictional surface 46, 47, for example, a serrated surface, in opposition to the surface of the roller 36. In addition, the surface 48 of the first insert 40 is provided with a first portion A which is disposed on a radius substantially equal to the radius of the surface of the cover 37 on roller 36 as well as with a second portion B which is tapered away from the roller 35 towards the second insert 41. The surface 47 of the second insert 41 also has a curvilinear surface corresponding to the radius of the surface of the cover 37 and to the surface portion A of the first insert 40.
The surface 46 of the first insert 40 is spaced from the surface of the rubber cover 37 of the roller 36 by a distance which is of a magnitude less than the diameter of a filter plug 11, that is, the nominal diameter of the filter plug 11. For example, for a filter plug having a diameter of inch, the distance between the insert member 40 and the cover 37 of the roller 36 is 5/16 inch. The surface 47 of the second insert member 41 is spaced from the roller 36 and the cover 37 by a distance substantially equal to the diameter of the filter plug and is therefore of a magnitude greater than the distance between the first insert 40 and the roller 36.
The edge of the first insert member 40 contiguous to the second insert member 40 is of slightly greater height than the contiguous edge of the second insert member 41 so as to provide a small step therebetween.
For purposes of illustration, the dimensions of the insert members are as follows. The first insert member 40 is of a length of 2 inches while the curvilinear portion A is of a length of 1% inches with a radius of 2% inches and a height at the initial end of 0.690 inches. The tapered portion B tapers from a height or thickness of 0.178 inches to 0.160 inches at the edge of the member 40. The second insert member 41 is of a length of 1% inches with the curvilinear surface 47 being formed of a radius of 2% inches. In addition, the thickness of the second insert member at the forward edge is 0.155 inches and at the tail edge is 0.650 inches. Both insert members 40, 41 are provided with serrations disposed with sidewalls at an angle of 60 and of a length of 0.050 inches and a throat width of the same length as a sidewall.
In forming the insert members 40, 41 each can be machined at the same time provided a shim plate is placed under the smaller member 41 to bring the memher up to the correct radius.
Referring to FIG. 5, the holder 38 is provided with a bevelled edge 48 adjacent the recess 39 which begins at a point contiguous to the tail edge of the second insert member 41 to provide a small continuous exit surface for a filter plug 11. The holder 38 also cooperates with a guide ramp 49 down which a rounded plug 11 can roll and a grooved delivery roller 50 which individually receives a filter plug 11 and transfers the filter plug into a suitable catcher 51.
The plug roller 35 can also be provided with a pneumatic device adjacent the delivery ramp 34 so as to facilitate entry of the filter plugs 11 into the passageway formed between the roller 36 and the insert members 40, 41 in a straight manner, i.e. parallel to the axis of the roller 36. In this respect, a conduit 52 is placed near the bottom of the ramp 34 so as to direct a continuous stream of air across the bottom of the ramp 34 into the passageway. In addition, the ramp 34 can be inclined in a manner so that the filter plugs 11 drop under gravity to a point on the holder 38 adjacent the entry to the passageway between the roller 36 and insert members 40, 41. A recess (not shown) can be formed in the holder at this point in a location corresponding to one end of a filter plug. This aids in aligning the filter plug in a straight manner before being blown under the roller 36.
In operation, after a filter plug 11 has been made on the machine (FIG. 1), the filter plug 11 is directed onto the ramp 34 (FIG. 5) for delivery into the plug roller 35. Next, upon rolling down the ramp 34 the plug roller is directed, as by the air stream of the conduit 52 into the passageway between the rotating roller 36 and the insert members 40, 41 in the holder 38. The filter plug 11 is then initially engaged by the roller 36, which is rotating in a counterclockwise direction as shown in FIG. 5, and rolled across the serrated curvilinear surface 46 of the insert member 40. At the same time, due to the restriction of the passageway, the plug 11 is deformed under a positive force. This causes the stiffness of the mouthpiece paper 22 and the plug wrap paper 16 to be overcome. Thereafter, the deformed filter plug 1 l is rolled across the transition portion B of the insert member 40 wherein the deformation force is relieved and rolled across the curvilinear surface 47 of the second insert member 41. In rolling across the surface of the second insert member 41, thefilter plug is driven by the roller 37 under a gentle rolling force which effects a rounding of the filter plug into the final rounded shape as shown in FIG. 7. Next, the filter plug is rolled away from the roller 36 across the bevelled edge 48 of the holder 38. The filter plug 1 1 then rolls down the remainder of the holder surface across the ramp 49 onto the delivery roller 50 from which the filter plug 11 is then directed into the catcher 51.
It is noted that the papers 16, 22 used in making the filter plugs are relatively thin compared to the diameter of the plugs and much thinner than as illustrated in the exaggerated FIG. 7 so that the final cross-sectional shape of the plugs upon emanating from the plug roller 35 is, for all practical purposes, a truly round circular shape both to the naked eye and to the touch.
The invention thus provides a simple apparatus of relatively few parts which is capable of rounding filter plugs into a truly round cross-sectional shape against the resistance of the various papers and materials which are used in the formation of the filter plug.
The invention also provides a technique whereby the out of roundness of a filter plug can be quickly and efficiently corrected.
What is claimed is:
1. An apparatus for obtaining rounded filter plugs for cigarettes comprising a pressure applying means having an endless movable surface thereon disposed in a preset position;
a first surface means made of metal and having a serrated friction surface spaced a first distance from said movable surface of said pressure applying means, said first distance being of a magnitude less than the diameter of a filter plug to cause a deformation of the filter plug during passage of the filter plug between said pressure applying means and said first surface means; and
a second surface means made of metal and having a serrated friction surface spaced a second distance from said movable surface of said pressure applying means, said second distance being of greater magnitude than said first distance and of a magnitude equal to the diameter of a filter plug to cause rolling of the filter plug between said pressure applying means and said second surface means after passage from said first surface means.
2. An apparatus as set forth in claim 1 wherein said movable surface of said pressure applying means is resiliently deformable.
3. An apparatus as set forth in claim I wherein said movable surface is made of rubber.
4. An apparatus as set forth in claim 1 wherein said friction surface of each surface means is a roughened surface.
5. An apparatus as set forth in claim 4 wherein each said friction surface is a curvilinear surface.
6. An apparatus as set forth in claim 5 wherein said pressure applying means is a rotatable roller.
7. An apparatus for rolling filter plugs comprising a rotatable pressure roller;
a first member having a roughened curvilinear surface spaced a first distance from said roller, said distance being of a magnitude less than the diameter of a filter plug to cause a deformation of the filter plug during rolling passage of the filter plug between said roller and said first member; and
a second member having a roughened curvilinear surface spaced a second distance from said roller, said second distance being of greater magnitude than said first distance and of equal magnitude to the diameter of a filter plug to cause rolling of the filter plug between said roller and said second member after passage from said first member.
8. An apparatus as set forth in claim 7 wherein said pressure roller has a resilient deformable surface thereon in facing relation to said members.
9. An apparatus as set forth in claim 7 wherein said surface of said first member has a first portion of arcuate shape and a second downstream portion of tapered shape.
10. An apparatus as set forth in claim 9 wherein said surface of said second member is of arcuate shape and extends from said tapered surface of said first member.
11. An apparatus as set forth in claim 10 wherein said second member is of a length less than said first memher and is of a height at the upstream end thereof slightly less than the height of said first member at the downstream end thereof.
12. An apparatus as set forth in claim 7 wherein said members are made of metal and said surfaces are serrated.
13. An apparatus as set forth in claim 12 wherein said pressure roller has a rubber surface in facing relation to said members.
14. An apparatus as set forth in claim 7 which further comprises a holder having a recess receiving said members therein in contiguous relation to each other to form a continuous surface of said curvilinear surfaces.
15. An apparatus as set forth in claim 14 wherein said holder has a beveled edge adjacent said recess and said second member to form a continuous surface with said second member.
16. An apparatus for rolling filter plugs for cigarettes comprising a rotatable roller;
a holder having a recess therein disposed below said roller;
a first insert member in said recess spaced a first distance from said roller to rollably engage and deform a filter plug passing therebetween; and
a second insert member in said recess contiguous to said first insert member and spaced a second distance from said roller to rollably engage the filter plug passing therebetween, said second distance being of less magnitude than said first distance.