FI60109B - FOERFARANDE FOER FORMNING AV ETT FOER EN CIGARRETT ELLER DYLIK TOBAKSPROUKUKT AVSETT FILTERS STAONGDEL - Google Patents

Description

ΓΒ] mvAdMISSION PUBLICATION ^ ΠΙΠΟ LBJ UTLÄGGNI NGSSKRIFT 6 U 1 0 9 * § £ § c <4S) -Ui, i ^ ^ ^ (51) K ».ik? / I» t.a3 A 24 D 3/02 ENGLISH I - FI N LAN D (21) P »t * nttlhak« nu «- PatMtantekmiit 770730 (22) H» k # ml * p * lvl - Antöknlnpd ·! 08.03-77 '' (23) Alkupiivft— GUtlghutsd · * 08.03.77 (41) Tullut | u | klMk * l - Bllvlt offvntlij 18.09.77

National Board of Patents and Registration m- *. ^. , (44) Date of publication and date of publication. - "

Patent and ocean registration Antttkan utiegd och uti ^ kriftan pubiicarad 31.08.8l (32) (33) (31) Requested «pays * - Bugtrd priority 17 * 03.76 20.12.76 England-England (GB) IO77U / 76 53089/76 (71) ) British-American Tobacco Company Limited, Westminster House, 7, Millbank, London SW1, England-England (GB) (72) John Anthony Luke, Romsey, Hampshire, Raymond John Harrison, North Baddesley, Hampshire, England-England ( GB) (7 * 0 Leitzinger Oy (5 ^) Method for shaping the filter rod part of a cigarette or similar tobacco product - Förfarande för moldning av ett för en cigarrett eller dylik tobaksprodukt avsett filters st & ngdel

The invention relates to a method for shaping a filter part of a filter for a cigarette or similar tobacco product, in which a bar of filter material is treated as it moves along a curved path in a direction transverse to the longitudinal axis of the bar. The invention also relates to an apparatus for carrying out a method of shaping a filter rod part, in which a rod of filter material is moved along a curved path in a direction transverse to the longitudinal axis of the rod.

In the device described in Swedish Patent Publication 336,753, the filter rods are arranged to be moved in said manner while being cut into separate pieces which are removed from the device in succession in rows for connection to cigarettes.

Instead, it is an object of the invention to provide a method and apparatus by which a rod-like filter material can be substantially reshaped to provide the desired smoke filtration effects or properties.

601 09 2

Previous proposals for making cigarette filters from a tan material have generally involved the design of a continuous rod or a rod whose length is many times the length of the actual filter, with the rod in question moving during processing or. during shaping in the direction of its longitudinal axis, usually at high speed. This causes manufacturing difficulties due, for example, to the limited time available for machining and shaping the high speed rod, the need for precise timing, and the periodic nature of the operations performed on the rod.

In order to overcome these manufacturing difficulties, the method according to the invention is characterized in that in order to shape the movable rod, the material rod and the heated shaping member are moved in contact with each other, whereby a recess is formed in the rod by means of the shaping member.

The device for carrying out the method is characterized in that it comprises a heated shaping member and means for moving the bar of material to be shaped and said shaping member in relation to each other in contact with each other.

Due to the relative movement between the filter rod and the shaping members, the invention achieves the following advantages: 1. Significantly longer processing time of the filter rod.

2. The device can easily switch from one filter rod model to another without uneconomical interruptions.

3. The device can produce certain types of filter rods, which are difficult and even impossible to manufacture by shaping axially moving filter rods. With the device according to the invention, filter rods with, for example, helical grooves can be easily manufactured.

4. Due to the longer contact time between the filter rod and the shaping members, the shaping members do not have to be heated to as high a temperature as in previously known shaping devices. The lower temperature 3 60109 also reduces the susceptibility of the filter media and the wrapping paper to damage.

In a preferred embodiment of the invention, for mutual movement of the filter rod and the shaping member, the rod is supported and conveyed on the circumference of the drum-like inner rotor, and the shaping member comprises a heated, curved outer stator element. or elements projecting inwards towards the rotor. Such an outer stator element may simply consist of a heated rod having a profile in contact with the filter rod, which is the complement profile of the groove formed in the filter rod, the groove being formed under the influence of the heat and pressure provided by such an element.

In general, the length of the filter to be formed is a multiple of the length of a single finished component, for example a cigarette filter.

The filter rod can also be rotated about its axis as it moves in a direction transverse to the axis of the circumference, but this rotation about the axis is not necessary. For this purpose, the filter rod can be supported on the circumference of the rotor by means of a pair of rollers extending parallel to the longitudinal axis of the filter rod, said rollers rotating about their axes, thus causing the filter rod to rotate about its axis.

By the above-mentioned method, various recess shapes can be formed, for example one or more annular grooves which extend continuously around the filter rod. Generally, the recess or groove extends only a portion of the length of the rod. To make a groove extending helically around the rod, the heated stator element can be placed at an angle other than a right angle to the filter rod placed transversely.

Because the filter rod is shaped as it moves transversely to its longitudinal axis, more time is available for shaping the filter rod 4 60109. Not only can a better design be achieved in a simple manner and with a simple device, it is also possible to economically manufacture a large number of different filters without having to use complex and expensive machinery for cutting and other work steps that would require periodic movement if longitudinal.

Filter rods can be made of various filter materials, such as thermoplastic polymers, for example cellulose acetate or polypropylene. Paper filters would be suitable if the paper were wetted or contained a certain amount of thermoplastic material or coated with a heat-activated adhesive. The rod material may contain additives, for example carbon. It can consist of concentric tubes, the inner part being, for example, paper and the outer plastic material. At least parts of the multi-part filter rods can be made in this way, although not all parts may be permanently deformable.

Before the actual shaping takes place, the filter material or filter rod can be sprayed or otherwise treated with a liquid additive of water or steam to bring the filter rod to the correct condition for handling and to minimize the risk of damage to the materials.

The shaped filter rod is preferably wrapped in the wrapping material while moving in a transverse direction with respect to the longitudinal axis of the filter rod. In this case, a simple wrapping step can be achieved. Said shaping and wrapping steps are preferably performed in the same machine or unit, which is preferably in combination with the filter mounting unit or machine.

In the following, an embodiment of the invention will be explained in full, but by way of example, with reference to the accompanying schematic drawings, in which:

Figure 1 is an overview of a complete filter rod manufacturing machine with forming and wrapping members, the figure showing the device from the end.

S 60109

Figure 2 is an elevational view of the shaping member at right angles and on a larger scale relative to Figure 1.

Fig. 3 is also an end view on a larger scale, showing the way in which the filter rods to be shaped are supported in the shaping member.

Figure 4 shows a filter rod shape that can be manufactured with the unit of Figure 2.

Fig. 5 is a block diagram showing ways of operating a machine or device.

The machine in Fig. 1 comprises a receiving drum 1, the circumferential surface of which has elongate grooves 2 for receiving rods 4 of uniform tobacco smoke filter material coming from a storage location (not shown) through a trough 3, which material may be, for example, cellulose acetate, the curved guide 5 holding the rods in positions parallel to the axis of the drum in the grooves as they move to the rod forming member 6 described below. position throughout the transfer. Drums 7 and 8 are provided with longitudinal rod receiving grooves in the same way as the frame 1.

The member 11 includes an alignment drum 12 and a wrapping drum 13, each of which has longitudinal rod receiving grooves and guides 12 * and 13 '. Drums 12 and 13 operate in a manner known per se. Wrapping material, for example paper, is fed to the drum 12 in the form of a continuous web 14 from a spool (not shown) with the aid of a roll 15. The latter cooperates with a cutting roller 16 having a plurality of radially extending knives 17 at suitable distances from each other to cut a web corresponding to the length of the filter strands 10 into separate pieces to wrap them around individual filter rods. in connection with the filter rod 10 in a known manner. In its path from the spool to the roll 15, a web passes a spreader (not shown) which applies an adhesive to the surface of the web 6 60109 which comes into contact with the filter jacks. Each piece of wrapping material with an adhesive coating is arranged in contact with a rod 10 running around the circumference of the drum 12. Together with the respective wrapping pieces, the filter rods 10 move from the drum 12 to the drum 13, where each rod in a position transverse to its axis rotates about its axis without moving in the longitudinal direction, each rod wrapping its own From the drum 13, the wrapped filter rods 18 are transferred to the adhesive belt 19 by a longitudinally grooved transfer drum 20 with a guide 20 '.

To operate the machine, drums 1, 7 to 9, 12, 13 and 20, rollers 15, 16 and a belt 19 from a power source (not shown) are used in alignment with each other and with the shaping member 6 to be explained below.

The shaping member 6 has a rotor and a stator part. The rotor part has two circular end discs 21 (Fig. 2) on which are mounted a circumferential series of small rollers 22, preferably with rounded surfaces. A pair of adjacent rollers 22 receiving rods from the drum 1a support them between the circumferential areas of said rollers while the rotation of the rotor conveys the rods through the unit. The rotor is suitably driven by a shaft 23 of an electric motor (not shown). The coupling indicated by reference numeral 24 may be provided between the end discs 21 to facilitate axial adjustment of the member to accommodate rods of different lengths to be placed in the member. The rotation of the rollers 22 about their axes is transmitted by rotating wheels 25, which wheels are attached at one end to long bearing pins and are in tooth contact with the central wheel 26. The center wheel 26 is rotatably mounted on a shaft 27 rotated by another motor (not shown). If, as shown here, the adjacent disc 21 is supported by a shaft pin 28 in the wheel 26 and / or in the bearing 29 on the shaft 27, a reciprocal axial adjustment. The motors can be speed-adjustable motors, in which case the motor speed and the speed around the axes of the rollers can be chosen to meet certain requirements, in particular so that the number of revolutions of the rods can be changed or controlled as they pass the stator. If this condition 60109 7 is not required, the driving forces required for the rotation of the rotor and the rotation of the rollers about its axes can be drawn from a common power source.

The stator part has a curved outer part 31 with radially inwardly projecting parts 32 in the form of curved ridges. The part 31 is provided with heating elements at least in the protruding parts, which are preferably electrical elements arranged in place in a known manner. The number, shape and arrangement of the protruding parts correspond to the required recesses 33 to be formed in the rod 10. The shape of the rod shown in Fig. 4 is given purely by way of example, the cross-sectional shape of the stator shown in Fig. 2 being complementary to this rod shape. The curved guides 34 (Fig. 1) extend from the ends of the part 31 to points located next to the drums 1 and 7, respectively.

The portion 31 and its protruding portions 32 extend generally at a constant radial distance from the rotor axis. However, the distance of said parts 32 to the rotor in the direction of rotation may decrease, whereby the shaping effect is progressive.

When the member 6 is used from the receiving drum 1 between the pairs of rollers 22, the rods arranged one by one move as the rotor rotates past the stator part 31, while at the same time rotating around the axes due to the rotation of the rollers 22. The rotating rods 10 are then pressed against the protruding stator parts 32 so that, under the influence of heat and pressure, recesses or spaced-apart areas 33 of smaller diameter than the actual rod are formed.

It is preferable to use means for rotating the rods about their axes by rotating the rollers 22. However, for some purposes, the rods can rotate only as a result of contact with the stator part 31. Elements can be provided to monitor the heating of the stator. The required temperature of the protruding parts 32 depends on the material properties of the filter rods and their residence time in the stator. The temperature should be between the softening and charring temperatures of this material. The temperature would be below the carbonization temperature of the paper if the filter rod were wrapped in paper during shaping. One advantage of the described arrangement is that the residence time can be made long, allowing low temperatures to be used and thus reducing the risk of damage to the filter material and the wrapping material.

If parts of the filter rod surface, either cylindrical outer surfaces or bottom and / or side surfaces of grooves or other recesses, should be partially or completely sealed against the ingress of smoke particles into the filter rod, this can be achieved by setting the stator temperature in the desired area or areas high enough to create a local surface. resulting in partial or complete closure or condensation of the filter rod material.

In practice, the member 6 does not normally shape rods 10 of single filter length, but mainly rods whose length is a multiple, for example six times the length of a single filter, whereby such rods are subsequently cut into single filter lengths.

A shaping member such as that described can be used to make various shapes of filter elements or parts thereof. The ring grooves may be rectangular in cross-section, as shown in Figure 4, or may be circular, V-shaped in cross-section, and may be arranged in any desired size, their position and number may be varied, and their depth and / or width may be constant or variable. . In addition, a generally cylindrical filter rod body with outwardly projecting annular ridges can be provided. Non-annular shapes, for example a helical groove or grooves, can be formed by using a stator whose protruding portions in the plane are at an angle other than at right angles to the transverse direction in which the rods extend slowly as they move about their axes but without axiality. movement, through the member 6, the pitch of the thread depending on said angle. Various V-shapes of the filter may be formed, for example conical, convex or oblique ends or corrugated, corrugated or brushed ends, optionally associated with at least partial sealing of said ends. The shaping can be performed mainly or partially in order to provide a differential sealing factor (the amount taken up by the volume of the filter when using a fibrous filter material). For example, the cylindrical rod portion may be associated with a sealed tapered portion.

In addition, formations can be arranged which do not extend around the entire circumference and which can be staggered on the circumference relative to each other. In addition, recesses 60109 can be provided which are bounded at the bottom by a tendon-boundary line. Such formations can be made by selecting the lengths, shapes and positions of the parts protruding into the stator and the rotational speed of the rotor. For some purposes, the rods are not allowed to rotate about their axes as the rotor rotates, with the recess forming only on one side of the rod. A similar recess can be formed on the opposite side by turning the rod around or feeding it to another shaping member 6.

Formations as shown can be made in connection with the inner cavity with the head or ends either open or closed using initially a hollow or tubular filter rod material.

The elongate formations can be made either alone or in conjunction with the circumferential formations by using protruding portions of the stator that extend transversely to the stator. If desired, a pattern of longitudinal recesses, cavities or perforations, ridges or teeth and associated stepped grooves can then be provided in combination with the circumferential recesses.

For many purposes, the desired formations can be made by using only one shaping member 6 to shape the filter rod.

However, more than one design member may be used to perform different design steps or to complete one entire operation in more than one step. The parts of the filter element can be formed by separate shaping elements and then brought together.

For example, in the case of filters with drinking bodies enclosed in a hollow cylinder, said cylinder may be closed by a conically terminating plug portion made as described above. For example, composite filters may have uniformly sized acetate plugs at the ends with the acetate portion used on the carbon in the middle, the latter being compressed to form an annular path through which smoke can flow past the carbon and not through it. A highly efficient filter with a cellulose acetate filtration feature may comprise two closed cylindrical bodies with a uniformly sized, hollow cylindrical filter body of smaller diameter interposed between adjacent conical ends.

The invention makes it possible to produce quickly a number of filters which could otherwise be produced, if at all, only with the greatest difficulty and expensive equipment and at relatively slow speeds. In addition, the invention makes it possible to diversify the filter rod manufacturing machine, since one type of rod forming device can be easily replaced by another in the same basic machine.

A filter rod wrapping machine such as that shown in Figures 1-4 can be used in many different ways and in suitable combinations with other devices. As shown, pre-cut filter rods 4 are fed into the machine from storage, and the shaped and wrapped rods 18 are delivered to storage by means of a belt 19. However, as schematically shown in Figure 5, the filter rod forming and wrapping machine or unit 35 may be connected to or connected to a known filter rod manufacturing machine or unit 36, which may be, for example, a machine fed filter material such as cellulose acetate fluff at 37 the manufactured and cut rods 4 are fed at 38 to a machine 35. For this purpose, a conventional grooved drum used in a known filter rod manufacturing machine to catch and fasten longitudinally moving rods and move them transversely to their axes can simply be replaced by means for feeding rods to the rotor of unit 6 shown in Fig. 1. In either of the above arrangements, the rods 18 need not be fed from the machine 35 to the warehouse, but may instead be fed at 39 directly to the filter attachment machine or unit 40, to which 42 pre-wrapped cigarette butts 41 are fed from either the warehouse or preferably directly from a known type of cigarette making machine 43. 1-4, it can be seen that the machine or unit 40 is constructed so that the filter rods 18 pass through it in a transverse position. As schematically shown, the tobacco rods 41 are fed from the machine 43 to the unit 40 in an axial position, which unit 40, like the unit 35, is located to the side of the machine 43. The cigarette rods 41 are then in a position suitable for connecting them to the coaxially shaped filter rods 18. In the unit 40, the cigarette rods 41 and the filter rods 60109 11 18 can be connected by known devices.

The units 35 and 40 can form an arrangement which can simply be fitted to the machine 41 and which can be used in parallel with it.

The rods 10 shaped to make double or multi-part filters can be cut into individual pieces before they are wrapped, with means provided for interposing second cut filter parts fed from different stocks. In order to obtain one filter at a time, one such section and these other parts are combined in one wrapping step.

Claims (16)

A method for shaping a filter rod portion of a cigarette or similar tobacco product, wherein the rod (4) of filter material is treated as it travels along a curved path transverse to the longitudinal axis of the rod, characterized in that the rod (4) and the heated shaping member (6) is moved relative to each other in contact with each other, whereby a recess (33) is formed in the rod by means of the shaping member. Method according to claim 1, characterized in that the rod (4) is supported and moved on the circumference of the drum-shaped inner rotor (21) for mutual movement of the rod and the shaping member, and that the heated, curved outer stator element or elements (31, 32) ) protrude inwards towards the rotor (21). Method according to Claim 1 or 2, characterized in that the rod (4) is also pivoted about its axis as it moves in a direction transverse to this axis. Method according to Claim 2 or 3, characterized in that the rod (4) is supported on the circumference of the rotor (21) by a pair of support rollers (22) which extend parallel to the longitudinal axis of the rod. Method according to Claims 3 and 4, characterized in that the support rollers (22) rotate about their axes, thus causing the rod to rotate about its own axis. Method according to Claims 1 to 5, characterized in that the shaped bar (4) is wrapped in the wrapping material (14) as it moves in a direction transverse to the longitudinal axis of the bar. Method according to claim 6, characterized in that the rod (4) moves between the shaping and wrapping steps (6 and 11) in a direction transverse to said axis. 13 601 09 Method according to Claims 1 to 7, characterized in that the surface or surfaces delimiting the recess (33), for example an annular or helical groove, are sealed during the shaping step, so that they become impermeable to smoke. Method according to Claim 8, characterized in that the recess (33) is a groove extending around the rod (4) and only the surfaces delimiting the groove or the bottom surface of the groove are sealed. Apparatus for performing a method of shaping a filter rod part according to one or more of claims 1 to 9, wherein the rod (4) of filter material is moved along a curved path in a direction transverse to the longitudinal axis of the rod, characterized by heated shaping member (6) and members (21, 22) for moving the rod (4) of material to be shaped and said shaping member (6) relative to each other in contact with each other. Device according to claim 10, characterized in that the members supporting and moving the rod (4) comprise a drum-shaped inner rotor (21) on the circumference of which the rod is moved, and that the shaping member has a heated, curved outer stator element or elements (31, 32) projecting inwards towards the rotor (21). Device according to claim 10 or 11, characterized in that it further comprises means (25-27) for turning the rod (4) about its own axis as it moves in a direction transverse to said axis. 12 60109 Device according to Claim 11, characterized in that support ends (22) are mounted at the ends of the rotor (21) to support the rod (4) and extend parallel to the longitudinal axis. Device according to Claim 13, characterized in that means (25-27) are provided for rotating the support rollers (22) about their axes, which cause the rod (4) to rotate about its own longitudinal axis. 14 60109 Device according to Claims 10 to 14, characterized in that a functional combination with the shaping elements (6) is a filter rod wrapping element (12), in which the rod (4) is wrapped while moving in a direction transverse to its longitudinal axis. Device according to claim 15, characterized in that the shaping member (6), the wrapping member (35, Fig. 5) and the filter fixing member (40) into which the wrapped filter rod (4) is fed are arranged as one unit on the side of the cigarette making machine (43). is arranged to supply cigarette rods (41) to the fastening member (40). 15 601 09