DE2711784A1 - Mfr. of grooved element for cigarette filter tip - uses hot forming tool along which rotating element is passed - Google Patents

Abstract

A cylindrical rod of the material to be formed is held in contact with a heated forming tool while the two are relatively displaced over a curved path transversal to the longitudinal axis of the rod. In this way a channel, groove or other impression is hot pressed into the rod by the tool. The rod is pref. held and carried in a longitudinal slot along the circumference of a rotor while a fixed tool has projections extending towards the rotor. While the rotor turns, the rod is pref. rotated on its own axis in a rotor slot; to achieve this conveniently, each slot is defined as the space between the two parallel, longitudinal, driven rollers. The impression formed by the tool in the rod is pref. a coaxial, helical and/or annular channel. Part or all of the channel surface is made impermeable to cigarette smoke during the forming operation. Tools and tool paths can provide a variety of impressions in the insert, and make selected areas of the impression impermeable to smoke. This facilitates altering the filtration characteristics of the tip element as desired.

Description

Method and device for the production of

Tobacco Smoke Filters The invention relates to the improved Manufacture of smoke filters, in particular filters for tobacco products, and in particular, but not exclusively, from tobacco smoke filters for cigarettes.

Previous proposals for making filters from bar stock concerned the machining of a continuous bar or a bar from several Filter tip lengths, while usually moving at high speed move in the direction of their longitudinal axis. This results in terms of manufacture Difficulties by limiting the time available that is necessary is, to machine the bars in a suitable way.

The object of the present invention is the method and to improve the apparatus for manufacturing filters such that areas of the rod-shaped material for the manufacture of the filter changed significantly can be in order to thereby the rod to achieve a desired smoke filtering to improve. Furthermore, the manufacturing process should be simplified.

The invention solves this problem with a method and a device for the design of a smoke filter rod, which is characterized in that a bar to be formed and a heated mold in contact with each other standing relative to one another on a curved treatment path in one direction are moved transversely to the longitudinal axis of the rod, whereby by means of the forming device an impression is made in the bar. Preferably the rod is for a Relative movement supported and promoted on the circumference of a drum-shaped inner rotor. The former has a heated, curved outer stator element or elements a if protruding inward towards the rotor. Such an element can consist in a simple way of a heated bar, which has a bar contact profile has, which with the through this in the rod under the action of heat and pressure corresponds to the impression to be produced. The rod to be trained has in in practice generally a length which is a multiple of the length of an individual Completely machined components, for example corresponds to a filter tip.

The rod can, but does not have to, during the relative movement in the direction be rotated transversely to their axis around their own axis. For this purpose, the Rod on the circumference of the rotor are supported by a pair of rollers that are parallel extend to the longitudinal axis of the rod. The rollers rotate around their axis, around the To put the rod in a rotary motion around its longitudinal axis.

Through the aforementioned method, various configurations of the Impressions can be made, e.g. in a simple case one or more ring-shaped Grooves that extend continuously around the rod. In general it will the impression only extend over part of the length of the rod.

To make one that extends helically around the rod Groove, the heated stator element can be arranged at an angle which is from deviates from a right angle to the transverse rod.

As during the movement of the rod in a direction transverse to its Longitudinal axis machining of the same takes place, stands for machining of the rod more time available. It just can't be done in a simple way and with simple Means a better molding process can be achieved, but it is also possible to manufacture a wide range of different filters economically without complicated and using expensive machines for pinching or other operations, which would require an interrupting movement in the event that the rods in the direction of their longitudinal axis would be moved.

The filter rods can be made of various filter materials, such as thermoplastic Polymers such as cellulose acetate or polypropylene. Paper filter would be suitable if the paper was either moistened or thermoplastic material or coated with a heat activated adhesive. The rod material may contain additives such as carbon. It can consist of concentric tubes, e.g.

an inner one made of paper and an outer one made of plastic material exist. Parts of at least composite or multiple filter rods can can be made in this way, even if not all parts are permanently deformable.

Before the filter material or the rod is formed, it can be sprayed or some other type of fluid additive treatment, including Water, or steam, is done to treat the rod and reduce the risk of damage of the material to a minimum.

Preferably, the formed rod is wrapped in wrapping material, while the rod is moved in a direction transverse to its longitudinal axis. This can a simple wrapping process can be carried out. Advantageously, the aforementioned form and wrapping operations performed on a single machine or assembly, preferably in combination with a device for connecting or attaching the filter tips.

Further details, features and advantages of the invention result purely from the following description of the accompanying drawings schematically illustrated embodiments. 1 shows a general Front view of a complete machine for the production of filter rods, including the molding and wrapping equipment, Figure 2 is a view of the molding device at right angles to Fig. 1 and on a larger scale, Fig. 3 is an end view of the Forming device in turn on a larger scale with representation of those supporting the rods Rollers, Fig. 4 is a perspective view of a filter rod configuration as they by the device according to FIG. 2, and FIG. 5 is a block diagram with the representation of the type of use of the machine.

The machine shown in Fig. 1 has a take-up drum l, which has longitudinal grooves 2 in its circumferential surface, which are not shown by a Magazine fed through a shaft 3 smooth, cylindrical rods 4 made of tobacco smoke filter material, e.g. cellulose acetate. The take-up drum 1 directs the means of a curved Guide plate parallel to the drum axis held in the grooves rods to a Rod forming device to be described below 6. Transfer devices in the form of three transfer drums 7, 8 and 9 with curved guide plates 8 'and 9' serve to transfer the filter rods formed in the device 6 10 to a wrapping device 11, the rods in their transverse orientation during throughout the entire transfer process. The drums 7 and 8 are elongated Bar grooves are provided, similar to drum 1.

The device 11 has a connecting drum 12 and a wrapping drum 13, which in turn have elongated rod receiving grooves and guide plates 12 'and 13 '. The drums 12 and 13 are unc ise operated. The drum 12 is wrapping material, for example paper, in the form of a continuous belt 14 with the support of a roller 15 of one not shown reel fed. This roller 15 cooperates with a cutting roller 16, which has a plurality of radially protruding knives 17, which are at suitable intervals are arranged around the band, the width of which is equal to the length of the rods 10, Separate into separate length sections around the individual rods to be wrapped. The length sections then become the drum through the roller 15 12 promoted, a length element doing with each rod in a known manner is associated. The belt 14 runs on its way from the reel to the roller 15 past an application device, not shown, which on applies adhesive to the area of the tape that will come into contact with the rod. Each length element bearing an adhesive layer is attached to a rod 10 in Brought in connection, which is located on the circumference of the drum 12. The poles 10 get together with the respective length elements made of envelope material from the Drum 12 to drum 13 where, in a position transverse to its axis, each rod rotated around its axis without longitudinal movement and wrapped in the respective length element the longitudinal edges brought into connection with one another by the adhesive be connected to each other. From the drum 13, the wrapped or wrapped Rods 18 through a longitudinally grooved transfer drum having a guide plate 20 ' transferred to a receiving belt 19.

When the machine is in operation, drums 1, 7-9, 12, 13 and 20, the rollers 15, 16 and the conveyor belt 19 from a power source, not shown driven in coordination with each other and the molding device now to be described.

The shaping device 6 has a rotor part and a stator part. The rotor part consists of two circular end plates 21 (Fig. 2), in which one circularly arranged row of small rollers 22 is mounted, which is preferably have a knurled surface. Pairs of these adjacent rollers 22 serve for receiving the rods from the drum 1 and for supporting the same between Circumferential areas of these rollers while the rods as the rotor rotates through the establishment to be worn. The rotor is driven by a shaft 23 on suitable Way driven by means of an electric motor, not shown. One schematic at 24 indicated coupling can be between the end plates 21 to facilitate the axial adjustment of the device with regard to the adaptation of different lengths the bars to be machined be provided. The rotation of the rollers 22 around their Axes is caused by planet gears 25, which on the protruding bearing ends of the rollers are fixed and mesh with a sun gear 26. The sun gear 26 is rotatably mounted on a shaft 27, which is driven by a motor, not shown is driven. If, as shown, the adjacent disc 21 means a connecting piece 28 is supported in a bearing 29 of the sun gear 26 and / or the shaft 27, can be a device, indicated schematically at 30, for a relative axial adjustment be provided. The motors can be those with controllable speed, so that the speed of rotation of the rotor and the speed of rotation of the rollers around their axes can be selected according to suitable requirements, so that in particular the number of rotations of the rods during their course through the stator can be varied or controlled, if this simplification is not required is, the drives for the rotation of the rotor and for the rotation of the rollers be of the usual type about their axes.

The stator has an outer curved part 31 with radially inward protruding molded parts 32 in the form of curved ribs. The part 31 is at least provided in the above areas with a heating device, which is preferably in the form of electrical elements, which in a known manner in the protruding parts are embedded.

The number, shape and arrangement of the protruding mold parts 32 fully correspond to the desired impressions formed in the rod 10 33. The shape of the rod according to FIG. 4 is to be regarded as a pure application example.

The cross section of the corresponding stator is shown in FIG. The curved guide plates 34 (Fig. 1) extend from the ends of the part 31 to adjacent points on drums 1 and 7, respectively.

The part 31 and its protruding mold parts 32 are generally extending at a constant radial distance from the axis of the rotor. However, the proximity of this Moldings 32 for the rotor can increase in the direction of rotation, so that the training effect, d. H.

the effect of producing the impressions increases.

When the molding device 6 is in operation, they are individually one after the other rods 4 displaced from the drum 1 between a pair of rollers 22 by rotation of the rotor carried past the stator 31, while the rods 4 through the Rotate rotation of the rollers 22 about their axes. The rotating rods 10 are against the protruding stator parts, d. H. the mold parts 32, pressed so that annular impressions or spaced apart zones of small diameter 33 formed in the bars under the action of heat and pressure.

A device is preferably provided for rotating the rods about theirs Axes with positive, d. H. direct drive of the rollers 22 for use.

For some purposes, however, the rods can also expand as a result rotate their contact effect with the stator part 31.

A device for controlling the stator heating can be provided be. The required temperature of the protruding mold parts 32 depends on the material properties the rods and their residence time in the stator. It should be between the melting temperature and the cooking temperature of the material. It would be below stewing temperature of paper if the bar is already wrapped in paper during the molding process were. An advantage of the arrangement described is that the residence time can be extended, whereby lower temperatures can be used and the risk of injury to the filter material and any envelope can be avoided can.

If it is necessary that parts of the surface of the rod, whether the outer cylindrical surfaces or the bottom and / or side surfaces of the grooves or other impressions, partially or completely against ingress of smoke components to be sealed in the rod, this can be achieved in that the stator temperature is sufficient in a required range or ranges is high to create a local superficial amalgamation from the one partial or complete sealing of the rod material results.

In practice, rods will be the length of a single filter normally not formed in a device 6, but rather bars of such a device Length, which is a multiple, e.g. B.

corresponds to six times the individual length of the filter. Such poles are then cut into individual lengths.

A molding device of the type described can be used for the production different types of training of filter elements or parts thereof are used will. Annular grooves can have a right-angled cross-section, as shown in Fig. 4 is shown. The cross-section can also be rounded, V-shaped or of of any other form, but can also be in any required training, Arrangement and number can be provided, with constant or changing depth and / or Broad. In the case of a substantially cylindrical rod, a body can also extend outwards protruding annular ribs can be achieved. Non-ring-shaped formations, z. B. a helical groove or helical grooves, can by using a stator with protruding parts are created, which are in a plane located, which is arranged at an angle that is from right angle to the transverse direction deviates in which the rods extend during the conveyance through the device 6, the rods rotating slowly about their axes, but without any axial movement. The slope of the helix depends on the angle mentioned.

Filter end designs can, for example, be conical, convex or inclined Ends or folded, wavy or ribbed ends may be connected be made with at least one partial seal of such ends. The molding process takes place directly or partially with the aim of achieving a different degree of compactness or a different compaction factor (the dimensioning of the in the case of fibrous Filter material occupied filter space). For example, a cylindrical Rod part next to a compacted, inclined or conical part.

Shapes can be provided that do not overlap extend the entire circumference and which over the circumference in relation to each other can be staggered. It can such impressions be achieved which are limited on the ground by a belt boundary or a profile boundary. Such Training can be done by choosing lengths, shapes and arrangements of the above stator designs can be produced, but also through the selection the speed of rotation of the rotor. For some purposes the poles are not supposed to can rotate around their axes when the rotor rotates, causing only one Side of the rod an impression is provided. A similar impression can be made on the opposite side can be made by turning the rod over or over a second molding device 6 is guided.

Such formations can be in connection with an internal cavity and with either a closed or open end can be made by initially a hollow or tubular rod material is used.

Elongated trainings can either be used alone or in conjunction with Circumferential formations are provided by using protruding stator parts, which protrude transversely from the stator. An execution of elongated impressions, cavities or perforations, ribs, or teeth, including staggered grooves, may appear this way in combination with circumferential impressions, provided this is desired or required.

For many purposes, required training can be achieved through use a single forming device such as the rod forming device. However, more than one mold assembly can be used to perform different molding operations or to complete an operation in more than one stage. Parts of a filter element can be processed by separate molding devices and provided with a certain shape and subsequently brought together.

For example, filters with ribbed bodies can be used in a hollow Cylinders are enclosed, the hollow cylinder by a conically ending closure part be closed, which was produced in the manner described above.

Composite filters can e.g. B. at the ends a flat acetate closure part and in the middle a carbon-enriched acetate part, the the latter part is assembled to form an annulus or ring path, through which the smoke can flow past the carbon instead of through it to stream. A high-performance filter lt cellulose acetate filter properties can have two massive cylindrical bodies with conical adjacent ends, the with a smooth, hollow, cylindrical filter body in between Are composed of diameter.

The invention enables high speed manufacture a number of filters which, if at all, only with great difficulty and expensive devices are manufactured at comparatively slower speeds could become. The invention increases the versatility of the machine for manufacturing of filter rods as one type of rod forming apparatus in the same basic machine can easily be replaced with another.

A bar forming and wrapping machine such as those in the context was described with FIGS. 1 to 4, can in different ways and used in close conjunction with other devices.

According to the representation, pre-cut from a warehouse or magazine Rods 4 fed. The shaped and wound rods 18 are conveyed through a conveyor belt 19 again delivered to a warehouse or magazine. Corresponding However, according to the schematic representation in FIG. 5, the rod forming and wrapping machine or device 35 combined or connected to a known production machine 36 will.

For example, this is a machine in which filter material, see B. Cellulose acetate mats or towels, added at 37 and manufactured by and cut bars 4 are transferred to the machine 35 at 38. For this purpose can usually be used in the known rod making machine for collecting and Define the longitudinal movement of the rods and their movement in one direction grooved drums used across their axes simply by a device be replaced for conveying the rods to the rotor of the device 6 according to FIG.

Alternatively, the device 6 can be located in the vicinity of a take-up drum be arranged, the rods being conveyed from this drum to the device will. With any of the foregoing arrangements, the rods 18 instead of the machine 35 to the warehouse or magazine at 39 directly to a facility 40 for Attachment of the filter tips are promoted. Also get into the facility 40 wrapped rods 41 of cigarette tobacco, as shown at 42, from a magazine or, advantageously, directly from a machine 43 on the production line of cigarettes. The machine or device 40 is designed so that using the bar forming and winding machine of the type operated with reference to FIGS. 1 to 4 Type the bars 18 traverse this machine 40. The tobacco rods 41 are in the axial position, as indicated schematically, from the machine 43 to Device 40 promoted, which with reference to the device 35 laterally is arranged by the machine 43. The rods 41 are in a suitable position for coaxial joining same with the shaped P iterstangen 18 shown. In the device 40, the tobacco rods 41 and the filter rods 18 in known manner and by known means be connected to each other.

The devices 35 and 40 can form an arrangement based on simple way with the machine 43 in connection and in common Coordination with this are driven.

In the manufacture of double or multiple filters, the shaped rods 10 are cut into individual independent lengths, before they are wrapped. Devices are provided for interconnection other cut filter parts fed from another source. For each filter, each of the lengths are cut off and a different part in joined together in a single shell.

Expectations:

Claims (16)

Patent pending process for designing a smoke filter rod, in that a material rod to be formed and a heated mold means standing in contact with one another relative to one another a curved treatment path in a direction transverse to the longitudinal axis of the rod are moved, whereby an impression is made in the rod by means of the shaping device will. 2. The method according to claim 1, characterized in that g e k e n n z e i c h -n e t that the rod for a relative movement on the circumference of a drum-shaped inner rotor is supported and conveyed and that the forming device is a heated, curved Has outer stator element or elements that point inwardly towards the rotor protrude. 3. The method according to claims 1 or 2, characterized in that g e -k e n n z e i c h n e t that the rod during the relative movement in the direction transverse to it Longitudinal axis is rotated about its longitudinal axis. 4. The method according to claim 2, characterized in that g e k e n n z e i c h -n e t that the rod is supported on the periphery of the rotor by a pair of rollers that extend parallel to the longitudinal axis of the rod. 5. The method according to claim 4, characterized in that g e k e n n z e i c h -n e t that the rollers rotate around their axis, around the rod in a rotary motion to offset their longitudinal axis. 6. The method according to any one of claims 1 to 5, characterized g e -k e n it is not indicated that the formed rod is encased in wrapping material, while moving in a direction transverse to the longitudinal axis of the rod. 7. The method according to claim 6, characterized in that g e k e n n z e i c h -n e t that the rod is moved transversely to between the forming and wrapping process their longitudinal axis is promoted. 8. The method according to any one of claims 1 to 7, characterized in that g e -k e n n z e i h n e t that one gives the impression, for example an annular groove or a helical groove, limiting surface or the limiting surfaces during the Forming process are sealed so that they are impermeable to smoke. 9. The method according to claim 8, characterized in that g e k e n n z e 1 c h -n e t that the impression is a groove arranged around the rod and which delimit the groove Surfaces or only the bottom surface of the groove are sealed. 10. Device for performing the method according to the claims 1 to 9, g e k e n n n z e i c h n e t by a heated molding device (6) and a device (22) for a relative movement of a bar of material to be formed (4) and the forming device (6) in a curved treatment path in a direction transverse to the longitudinal axis of the rod (4), the rod (4) and the Forming device (6) are in contact with one another. 11. The device according to claim 10, characterized in that g e k e n n -z e i c h n e t that the rod (4) for a relative movement on the circumference of a drum-shaped Inner rotor rests and is promoted, and that the molding device (6) is a heated, curved outer stator element (32) or elements, which inwardly towards protrude on the rotor. 12. Device according to claims 10 or 11, characterized g e k e n nz e i c h n e t that the rod (4) during the relative movement transversely to their Longitudinal axis is rotated about its longitudinal axis. 13. Device according to one of claims 10 to 12, characterized g e k It is noted that a pair is used to support the rod (4) on the rotor circumference Rollers (22) running parallel to the longitudinal axis of the rod (4) are provided. 14. The device according to claim 13, characterized in that g e k e n n -z e i c h n e t that a device (25, 26) is provided with which a rotation of the rollers (22) takes place around its axis, a rotation of the rod (4) generated around its axis will. 15. Device according to one of claims 10 to 14, characterized g e k It is noted that a rod wrapping device (11) is operational Combination with the molding device (6) is provided in which the molded pole (10) is wrapped while moving in a direction transverse to its longitudinal axis will. 16. The device according to claim 15, characterized in that g e k e n n -z e i c h n e t that the molding device (6), the wrapping device (11) and a device for connecting the filter tips to a tobacco rod to which the wrapped rods be promoted, as an overall arrangement on the side of a cigarette making machine are assigned, wherein the tobacco rods are promoted to the connecting device.