GB1602133A

GB1602133A - Apparatus for producing an area of desired permeability to air in wrapping material of or for rod-like articles of the tobacco-processing industry

Info

Publication number: GB1602133A
Application number: GB5082/78A
Authority: GB
Original assignee: Hauni Werke Koerber and Co KG
Current assignee: Koerber AG
Priority date: 1977-02-09
Filing date: 1978-02-08
Publication date: 1981-11-04
Also published as: IT7820086A0; DE2751522C2; DE2751522A1; JPS6113795B2; FR2379992B1; JPS53101600A; FR2379992A1; IT1158433B

Description

(54) APPARATUS FOR PRODUCING AN AREA OF DESIRED PERMEABILITY TO AIR IN WRAPPING MATERIAL OF OR FOR ROD-LIKE ARTICLES OF THE TOBACCO-PROCESSI9G INDUSTRY (71) We, HAUNI-WERKE KöRBER & CO. K.G., a German Company of Kampchaussee 12-22, 2050 Hamburg 80, Germany (Federal Republic) do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to an apparatus for producing an area of desired permeability to air in wrapping material of or for rodlike articles of the tobacco-processing industry on a machine for producing rod-like articles.

Within the scope of the invention, the term "machines for producing rod-like articles" is intended to mean all commercially available machines of the tobacco-processing industry, on which articles of this type are produced or processed from tobacco, smokable tobacco substitutes and filter material, such as for example cigarette rod machines, filter rod machines and filter attachment machines.

Providing smokable articles with an area of desired permeability to air (perforating the wrapping in the region of the mouthpiece end), through which cool air from the atmosphere is mixed with the smoke, is gaining increasing significance. The proportions of nicotine and condensate in the smoke can be influenced by means of the secondary air drawn-in through this area at the time of smoking. In order to be able to adhere to predetermined values for nicotine and condensate in the smoke of a smokable article with an area of desired permeabiltiy to air, it is necessary to keep the proportion of secondary air drawn-in through this area at the time of smoking, as constant as possible in proportion to the smoke for articles of one type.

It is known to insert holes by means of needles or the like in the mouthpiece end in the course of a rolling operation, by mechanical means, for example on a filter attachment machine. These needles are naturally subject to wear, resulting in changes in the size of hole of the perforations introduced, which must be corrected by adjusting the perforation means. On the other hand, the wear makes it necessary to change the perforation means at intervals.

The object of the invention is to facilitate troublefree perforation with means which are not subject to wear on machines of the said type.

According to a first aspect of the present invention there is provided apparatus for producing an area of desired permeability to air in wrapping material of or for rodlike articles of the tobacco-processing industry on a machine for producing rod-like articles, wherein the machine is provided with at least one radiation source for producing at least one beam of coherent radiation, means for pulsing the beam for the purpose of introducing a desired number of holes in selected regions of the wrapping material, and control means in operative connection with the main machine drive, for synchronising the pulsing means.

The advantage achieved by the invention consists in that both the size of the holes as well as the interval between the individual holes and thus the desired permeability to air can be preserved very accurately. The source of radiation is preferably a laser. According to a preferred embodiment of the invention, the radiation source precedes a wrapping device and the pulsing means is synchronised by the control means in such a way that the pulse sequence for the purpose of producing a desired number of holes per unit length of a strip of the wrapping material is synchronised with the speed of the wrapping material strip supplied continuously to the wrapping device.

Alternatively, the radiation source may be associated with a transverse conveyor for conveying rod-like articles with their ends overhanging the conveyor so as to intersect the radiation beam, the control means being adapted to synchronise the pulsing means with the conveying cycle so that, in use, the peripheral surface of an article passing the radiation source is provided with at least one hole.

In a further variant, the radiation source is associated with a rod conveyor for transporting a wrapped rod and the control means are adapted to synchronise the pulsing means with the speed of the rod such that a desired number of holes is produced in selected peripheral sections of the rod.

In order to ensure that the proportion of secondary air mixed with the smoke does not fall below a predetermined value, monitoring means for the area of desire permeability to air are preferably also provided, which are in operative connection with a correcting element for varying the energy of the radiation source or for shifting the focal point of the radiation, for the purpose of controlling the size of holes in this area. The monitoring means may appropriately be associated with the finished article.

It is naturally also conceivable to influence the permeability to air of the perforations by varying the number of holes.

In order to provide filter cigarettes in particular, without great expenditure, as they are conveyed at right-angles to their axes, with a plurality of holes arranged in the form of a ring over their periphery, there is provided according to a second aspect of the invention, apparatus for producing an area of de sired permeability to air in wrapping mat erial of rod-like articles of the tobacco-process- ing industry on a machine for producing rod like articles, on which the articles are conveyed at right-angles to their axes, wherein a transverse conveyor constructed as a rolling drum and an associated counter-rolling surface are adapted to be driven in opposite directions at co-ordinated speeds such that an article guided therebetween is rotated about its own axis at a fixed locus, a radiation source is provided for producing at least one beam of coherent radiation directed at said locus, and means is provided for pulsing the beam for introducing a desired number of holes into the wrapping material over the periphery of the article.

The advantage achieved with this con-.

struction consists in that without interrupting their conveyance towards or away from the perforating station, the articles, e.g. double filter cigarettes, are made to carry out a rotary movement at the latter, beginning or ending at a predetermined instant such that a plurality of holes with perfect edges is introduced in the peripheral surface of the wrapping material strip at uniform intervals in a manner which treats the cigarettes carefully, i.e. does not deform them and the diameter of the holes remains largely constant.

Preferably, the radiation source is associated with control means in operative connection with the main machine drive for synchronising the pulsing means.

Preferably, the source of radiation is a laser. On filter attachment machines, it is normal firstly to place filter mouthpieces of double length between two tobacco rods and to form a double filter cigarette from the latter. Before cutting this double filter cigarette into two individual filter cigarettes, it is normal to perforate the latter. For this purpose, it is also proposed according to a preferred embodiment of the invention that in order to act upon the wrapping material strip of a double article, the source of radiation comprises two radiation heads arranged side-by-side in the longitudinal direction of the article. A particularly favourable arrangement for commercially available filter attachment machines is ensured according to an additional embodiment if the source of radiation is located inside the rolling drum.

In order to co-ordinate the beginning and end of the rolling operation exactly with the position of the source of radiation, an additional embodiment provides that the counterrolling surface constructed as a rolling belt is provided with raised rolling surfaces following each other at a distance apart, whose length corresponds to the distance between two grooves on the rolling drum for positioning the articles before rolling and after rolling.

In order to preclude changes in the timed sequence of the rolling operation with respect to the control of the laser, in the long term, according to the invention, the rolling belt is preferably also constructed as a toothed belt.

In order to prevent damage to the rolling belt by the laser, at the time of an interruption in the flow of articles conveyed, i.e. if an article is missing, it is also proposed that the rolling belt preferably consists of a plurality of toothed belts arranged in spaced parallel relationship and between which the radiation is directed.

In a particularly appropriate compact construction, which facilitates a defined beginning or defined end of a rolling operation for successive articles, in every case, the counter-rolling surface is a roll body, which is provided over the periphery with alternate successive elevations and recesses.

The peripheral length of the elevations preferably corresponds to the distance between two grooves on the rolling drum for positioning the article before and after rolling of the latter.

The roll body may be provided with three rolling cylinders for engaging and rolling a double article, a radiation head being res pectively associated with the central rolling cylinder of the latter, on both sides. Preferably, the radiation heads are associated with a single laser whose beam is divided or a separate laser is associated with both sides of the central rolling cylinder According to a third aspect of the present invention there is provided apparatus for producing an area of desired permeability to air in wrapping material of rod-like articles of the tobacco-processing industry on a machine for producing rod-like articles, on which the articles are conveyed at rightangles to their axes, comprising a transverse conveyor provided with a rolling surface and associated with a stationary counter-rolling surface such that the articles are conveyed and rotated about their own axes in use, a laser, means for guiding or deflecting the laser beam onto the articles during their conveyance and rotation, means for pulsing the beam for the purpose of producing a desired number of holes in selected regions of the wrapping material, and control means in operative connection with the machine drive for synchronising the pulsing means.

The stationary counter-rolling surface is preferably part of a rolling block and the laser or the means for guiding or deflecting the laser beam are preferably controlled such that the articles are completely penetrated.

The transverse conveyor is preferably constructed as a rolling drum.

Preferably, the means for guiding or deflecting the laser beam comprises flat mirrors located on the periphery of a rotary drum, which mirrors deflect the incident laser beam towards the articles. The arrangement is preferably such that associated with each pulse of the laser during the rolling of an article is another angle of incidence of a mirror causing the laser beam to strike the article at right-angles.

The invention is described in detail hereafter with reference to embodiments illustrated in the drawings: Figure 1 shows a filter attachment machine of the MAX S type of Hauni-Werke, Hamburg, Bergedorf, Figure 2 shows a laser head associated with a tipping strip withdrawal device of the machine according to Figure 1, Figure 3 shows a laser head for the apparatus according to Figure 2, Figure 4 shows a section of tipping strip perforated by the laser head according to Figure 3, Figure 5 shows a laser head associated with a transverse conveyor for filter cigarettes, Figure 6 shows details of the laser head according to Figure 5, Figure 7 shows a cigarette rod machine of the GARANT type of Hauni-Werk, Hamburg, Bergedorf, Figure 8 shows a laser head associated with the wrapping strip of the machine according to Figure 7, Figure 9 shows details of the laser head according to Figure 8)section 8, Figure 10 shows a section of the wrapping strip perforated by the laser head according to Figure 9, Figure 11 shows a laser head associated with the wrapped rod on the machine according to Figure 7, Figure 12 shows details of the laser head according to Figure 11, Figure 13 shows a rolling device associated with a transverse conveyor of the machine according to Figure 1 and combined with a laser, Figure 14 is a partial longitudinal section through the apparatus on line XIV-XIV of Figure 13, Figure 15 shows a modified apparatus for perforating filter cigarettes on a transverse conveyor according to Figure 1 during rota tion about their axis, at rest, Figure 16 is a front view of the transverse conveyor according to Figure 15, and Figure 17 shows a further variation for perforating filter cigarettes during their over rolling, as they are conveyed transversely.

The filter attachment machine according to Figure 1 has the following details: An inlet drum 1 transfers the cigarettes produced on a cigarette production machine to two grading drums 2, which re-arrange the cigarettes supplied in staggered manner and supply them to an assembly drum 3 in rows of two with a gap between the cigarettes. The filter rods pass from a maga zine 4 to a cutter drum 6, are cut by two circular cutters 7 to form filter plugs of double length, re-arranged on a grading drum 8, made to form a row of plugs located one behind the other by a shifter drum 9 and deposited in the gaps in the cigarette rows on the assembly drum 3 by an accelerator drum 11. The garette/filter/cigarette groups are moved together, so that they lie axially side-by-side. They are then received by a transfer drum 12. A tipping paper strip 13 is withdrawn from a tipping paper reel 14 by means of a withdrawal roller 16. The tipping paper strip 13 is guided around a pretreater 17 comprising a sharp edge, glued by a glueing device 18 and cut on a tipping roller 19 by a cutter drum 21. The cut tipping paper pieces are stuck to the cigarettes/ filter groups on the transfer drum 12 and rolled around the cigarettes/filter groups on a rolling drum 22 by means of a rollhand 23.

The finished groups of double filter cigarettes are supplied by a drying drum 24 to a cutter drum 26 and made into individual filter cigarettes on the latter by cutting centrally through the filter plug, in which case faulty filter cigarettes are simultaneously ejected.

A turning device 29 co-operating with a transfer drum 27 and a collecting drum 28 turns one row of filter cigarettes and simultaneously transfers it into the unturned row of filter cigarettes travelling by way of the transfer drum 27 and collecting drum 28. The filter cigarettes pass by way of a checking drum 31 to an ejection drum 32, on which the heads of the filter cigarettes are scanned before the ejection operation. A catcher drum 34 co-operating with a brake drum 33 deposits the filter cigarettes on a catcher belt 36. Either a laser head 37 in the region of the tipping paper strip 13 or alternately a laser head 38 in the region of a transverse conveyor, in the present case the collecting drum 28 is associated with the filter attachment machine.

Figures 2 to 4 show further details as regards the arrangement of the laser head 37.

The laser head 37 consists of a resonator 39, in which laser beams are produced and a radiation head 41 with several mirrors and lenses for dividing, deflecting and focussing the laser beams produced. According to Figure 3, the radiation head 41 consists of a semi-transparent mirror 42, which allows part, in the present case half of the laser beams produced by the resonator 39 to reach a converging lens 43 and reflects the other half of the rays to a deflecting mirror 44, which once more deflects them to a converging lens 46. The converging lenses 43 and 46 focus the divided laser beams on the continuously withdrawn tipping paper strip 13.

In order to introduce a desired number of holes in the moving tipping paper strip, at intervals, means 48 for producing pulses, shown as a mechanical switch to simplify the illustration, are provided in the energy supply to the laser head 37, illustrated as a lead 47. In order to synchronize the pulse sequence with the speed of the tipping paper strip 13, control means 49 are provided, consisting a timing disc 51 derived from the drive of the filter attachment machine, a proximity detector 52 as well as a control member 53. In this way, two rows of holes 55 are produced in the tipping paper strip 13 according to Figure 4. Naturally, more than two rows of holes could be introduced in the tipping paper strip 13 by further division (not shown) of the laser beams.

In addition, the filter cigarettes are checked on the checking drum 31 in the region of their perforations, as regards their permeability to air, for which purpose a checking device 54 is provided. The checking device 54 consists in known manner of a pneumatic measuring chamber 56, shown diagrammatically, a measuring device 57, an integrating arrangement 58 and a reference value transmitter 59. The measuring device 57 for the checking air pressure is constructed as a pneumatic/electrical transducer in the form of a checking membrane receiving checking air, whose position is monitored capacitively.

The measuring device may be constructed as described in the Applicant's U.S. Patent Specification 3,412,856. For each filter cigarette Z, the measuring device 57 sends a measurement signal to the integrating ar rangement 58, whose output signal reproduces the permeability to air of the perforations of a predetermined number of filter cigarettes. A comparison arrangement 61 is connected on the one hand to the integrating arrangement 58 and one the other hand to the reference value transmitter 59. The comparison arrangement 61 is also connected to a control unit 62. The control unit 62 is connected to a correcting element in the form of an adjustable compensating resistance 63 connected in the lead 47, which resistance is controlled by the control unit 62 according to the input signal from the comparison arrangement 61 (control deviation). In this way, the energy supply of the laser can be varied depending on the checking signals.

Figure 3 shows a variation for changing the size of holes of the perforation, which consists in that the control unit 62 acts on a correcting element 64 shown in dot-dash lines, due to which the distance of the two lenses 43 and 46 from the tipping paper strip 13 is varied and thus the focal point of the laser beams is shifted.

It should be mentioned that the means 48 for producing pulses can be constructed in a manner other than interrupting the supply of energy. It is thus possible to consider hole masks or the like for example, which interrupt the laser beam directly or allow the latter to pass. However, perforated drums or the like are also possible, over which the tipping paper strip is guided, in which case the pattern of holes on the drum determines the size, number and arrangement of holes in the tipping paper strip 13.

As regards the alternative arrangement of the laser head 38 according to Figure 5, parts which correspond to those of the previously described figures are provided with reference numerals increased by 100 and are not described again in detail. In this case, the laser comprises a radiation head 166 according to Figure 6, which is associated with the collecting drum 28 such that the finished filter cigarettes Z conveyed at right-angles to their axes on the collecting drum 28 are provided with holes directly in the region of their mouthpiece. For this purpose, the radiation head 166 comprises a semi-transparent mirror 167, which supplies part of the beams by way of deflecting mirrors 168 to 171 to a converging lens 172 and supplies the other part of the laser beams by way of de flecting mirrors 173 and 174 to a converging lens 176. The converging lenses 172 and 176 focus the laser beams directly on the mouthpiece end of the filter cigarette Z, so that two holes are introduced in the paper at opposite ends. Further holes may naturally be introduced in the mouthpiece end by further division of the laser beams by means of appropriately located dividing and deflecting mirrors and additional converging lenses.

Another possibility (not illustrated) for perforating articles conveyed at right-angles to their axes, may consist in that the articles are rolled as they are conveyed and thus intersect the path of rays of the laser or that the articles rotate about their own axis at rest, in which case an appropriately controlled laser introduces holes in the form of a ring one after the other in the mouthpiece end.

Another possibility of using the laser will be described briefly with reference to Figure 7.

Figure 7 shows a cigarette rod machine of the GARANT type of Hauni-Werke, Hamburg, Bergedorf.

A tobacco stream is formed in a tobacco duct 78 from a tobacco fleece showered on a tobacco belt 77. A shaping wheel 79, which is provided on its periphery with a U-shaped groove having a perforated base, to which vacuum intake air is supplied in the region of the feed path, receives the tobacco stream from the tobacco belt 77. An equalizer 81 removes the excess in the tobacco stream on the shaping wheel 79 and thus forms the tobacco rod 82. A rod conveyor 83 operating by suction lifts the tobacco rod 82 out of the groove in the shaping wheel 79 and deposits it on a cigarette paper strip 84 guided in synchronism, which strip is wthdrawn from a reel 86, guided through a printing unit 87 and placed on a driven shaping belt 88.

The shaping belt 88 conveys the tobacco rod 82 and the cigarette paper strip 84 through a shaping device 89, in which the cigarette paper strip 84 is folded around the tobacco rod, so that one edge still projects. A glueing device 91 glues this edge and a seam plate 92 dries the adhesive seam. A cigarette rod 93 formed in this way is cut by a cutter device 94 into individual cigarettes, which are inserted by an accelerator 96 in a catcher drum 97.

A laser head 98 in the region of the paper strip supply in front of the inlet to the shaping device or alternate a laser head 99 in the region of the rod in front of the cutter device 94 is associated with the rod machine, which are described briefly hereafter with reference to Figures 8 to 12.

As regards the laser head 98, parts in Figures 8 to 10, which corresponds to those of Figures 2 to 4, are provided with reference numerals increased by 200 and are not described again in detail.

The laser head 98 associated with the cigarette paper strip 84 comprises a radiation head 101, whose construction is illustrated in detail in Figure 9. The laser beams produced by the resonator 239 are divided by four deflecting mirrors 102 to 106 of varying permeability and deflected to four converging lenses 107 to 111, which focus four laser beams side-by-side on the cigarette paper strip 84. The arrangement of the holes 254 produced in this way in the moving cigarette paper strip 84 according to Figure 10 is produced by an appropriately constructed pulse generating disc 251, which after two pulses occurring shortly one after the other emits the next pulse only after a longer time interval, so that a pattern of holes according to Figure 10 is produced. The perforation is checked by the checking device 254 exactly as in the afore-described examples.

In the following description of the variation according to Figures 11 and 12, parts which correspond to those of Figures 2 to 4 are given reference numerals increased by 300 and are not described again in detail.

The laser head 99 for inserting a perforation in the wrapped cigarette rod 93 com prises a radiation head 111, which is con structed according to Figure 12. In this em bodiment, three laser beams are directed from different sides onto the cigarette rod Z by means of six dividing or deflecting mirrors 113 to 119 and three converging lenses 121 to 123. Successive sections of rod receive three successive rows of holes extending in the form of a ring, due to three pulses pro duced shortly one after the other by the pulse generating disc 351.

Similar arrangement of laser heads as on the cigarette rod machine may naturally also be provided on a filter rod machine.

Figures 13 and 14 show further details relating to the apparatus for inserting a perforation in the tipping paper strip 413 wrapped around the double filter cigarettes and in the filter plug.

In order to roll the double filter cigarettes 437 transferred by the rolling drum 422 to the rolling drum 424, once more, a rolling belt 439 is associated with the rolling drum 424 comprising grooves 438, which rolling belt 439 is constructed as a toothed belt on its inner side and is guided around rollers 441 and 442 and a driving roller 443.

According to Figure 14, the rolling belt 439 consists of several, in this embodiment of three rolling belts 439a, 439b and 439c extending parallel to each other at a distance apart, which are all provided on their surface with raised rolling surfaces 444 following each other at a distance apart. The length of each rolling surface 444 thus corresponds to the distance between two grooves 438A and 438B on the rolling drum 424 for posi tioning the double filter cigarettes 437 before or after they are rolled.

Located inside the rolling drum 424 con sisting of several drum discs 446 is a source of radiation in the form of a laser 447, which according to Figure 14 comprises two radia tion heads 448 and 449, which are directed towards the gaps between the rolling belts 439a and 439b respectively 439b and 439c.

The laser 447 comprises a resonator 451, in which the laser beams are produced, which are then supplied by way of a semi-trans parent deflecting mirror 452 to a converging lens 453 of the radiation head 449 and by way of a deflecting mirror 454 to a con verging lens 456 of the radiation head 448.

The converging lenses 453 and 456 focus the divided laser beams on the tipping paper strip 413 of the double filter cigarettes 437, which are firstly received in grooves 438A of the rolling drum 422. In which case all the grooves 438 are connected to suction channels 457, which is only shown on two grooves in the drawings. When a double filter cigarette 437 on the feed path of the rolling drum 424 reaches the range of radiation of the laser 447, it is engaged by the leading edge of a rolling surface 444 of the rolling belts 439 moving in the opposite direction to the rolling drum 424 at the same speed and in this way is held stationary exactly at the point of the laser beam directed onto the latter and thus rotated about its own axis.

In order to introduce a ring-shaped series of holes at regular intervals in the tipping paper strip 413 or the mouthpiece end of the double filter cigarettes 437, during this sequence of movements, means 459 for pro ducing pulses, shown as a mechanical switch for the sake of clarity of the drawings, are provided in the means for supplying energy to the laser 447, illustrated as a lead 458.

In order to synchronize the pulse sequence of the laser beams to the rotary speed of the double filter cigarettes 437, control means are provided consisting of a pulse generating disc 461, whose drive is taken from the main drive of the filter attachment machine, a proximity detector 462 as well as a control member 463. On its periphery, the pulse generating disc 461 comprises control seg ments 464, of which each control segment 464 is provided with teeth 466, according to one control segment 464A of the pulse gen erating disc 461 illustrated in detail, in the present embodiment with ten teeth.

When a double filter cigarette 437A on the rolling drum 424 arrives in the engagement region of the rolling belt 439, in which the leading edge of the rolling surface 444A engages the double filter cigarette 437A and begins to rotate the latter, the first leading tooth 466A of the control segment 464A is located opposite the proximity detector .46?, so that a first signal activates the control member 463 for initiating a first pulse of rays from the laser 447. Since the rolling surface 424A of the rolling drum 424 and the rolling surface 444A of the rolling belt 439 move at equal speeds in opposite directions, the cigarette 437A stops at a point and rotates about its own axis, in which case said rolling surfaces 424A and 444A travel past the double filter cigarette 437A below or above. Since the teeth 466 of the control segment 464A travel past the proximity detector 462 in synchronism with this rotary speed, ten holes are introduced in the peripheral surface of the mouthpiece of the double filter cigarette 437A one after the other at uniform intervals by a corresponding sequence of pulses of the laser 447.

During this sequence of movements, the leading groove 438A of the rolling surface 424A has released the double filter cigarette 437A, whereas at the end of the rotary movement of the double filter cigarette 437A, the lagging groove 438B has reached the latter and receives and discharges it at the time on both sides of the rolling cylinder 511. In order to obtain a laser beam for each of the radiation heads 514, 516, the laser beam leaving the laser 517 is divided outside the production machine by a slightly inclined beam divider 518, which reflects part of the beam thorugh a deflecting mirror 519 and directs both laser beams by way of further deflecting mirrors 521, 522, 523, 524, 526 and 527, via the radiation heads 514, 516, to the double filter cigarette 501. In Figure 15, one part of the beam is shown only as far as the deflecting mirror 519, and only the other half of the beam is illustrated completely.

According to one variation, instead of the single laser 517, a second laser 526 (shown in broken lines) can be provided in addition to the laser 517, so that the beam leaving the laser 517 does not need to be divided, but the second beam is provided by the laser 526. This construction has the advantage that the power losses or power drift of the partial beams occurring when the beam is split, are precluded. Also associated with the laser 517 in known manner are a gas supply 527 with an inlet pipe 528 and an outlet pipe 529, a supply of coolant 531 with a feed pipe 532 and a discharge pipe 533 as well as an energy production unit 534 with high voltage connections 536 and 537.

In addition, the energy production unit 534 is provided with a control unit 538, which is in operative connection with a proximity detector 539, with which control segments 541 are associated, which are located in the form of a circle on the end face of the rolling drum 502 and can be driven at the speed of the latter.

For the sake of greater clarity of the drawing, only part of the control segments 541 have been shown. The control segments 541 associated with each rolling surface 508 of the rolling drum 502, located between two grooves 503a and 5053b, are respectively provided with ten pulse generators 542.

When a double filter cigarette 501 on the feed path of the rolling drum 502 reaches the range of radiation of the radiation heads 514 and 516, it is engaged by the respective leading edge of a counter-rolling surface 507 of the roll body 506 moving in the opposite direction to the rolling drum 502 and at the same peripheral speed and in this way is held stationary exactly at the point of the laser beams directed towards the latter and is thus rotated about its own axis. The pulse generators 542 moved past the proximity detector 539 in synchronism with the speed of rotation send ten successive control signals to the control unit 538 of the laser, which respectively burns ten holes in the peripheral surface of the rotating double filter cigarette 501 according to the pulse sequence. During this operation, the double filter cigarette 501 is moved out of the groove 503a conveying it into the radiation range, in which case the vacuum is briefly reduced or even completely eliminated at least in the outer end regions of the groove located opposite the rolling cylinders 509 and 512. At the end of the rolling operation, the respective trailing groove 503b reaches the double filter cigarette 501 and receives the latter with the assistance of the vacuum. Since, at this instant, a recess between two counter-rolling surfaces 507 of the rolling body 506 reaches the rolled double filter cigarette, the latter can be discharged in an unhindered manner. In order to increase their gripping capacity, the rolling surfaces 508 of the rolling durm 502 may also be provided with a roughening.

In the further variation according to Figure 17, double filter cigarettes 601 are likewise conveyed on a rolling drum 602. In this case, each double filter cigarette 601 conveyed is held by suction in a flat groove 603 in a manner which is not shown, in which case, a tipping paper piece 604 is stuck to each double filter cigarette 601 or likewise held on the periphery of the drum by suction.

A stationary rolling block 606 with a counterrolling surface 608 located opposite the rolling surface 607 of the rolling drum 602 is associated in known manner with the rolling drum 602 at a distance equal to or somewhat less than the diameter of a cigarette. At the inlet end of the gap formed between the rolling surface 607 and the counter-rolling surface 608, the rolling block 606 is provided with a rolling bar 609, whose distance from the rolling surface 607 is somewhat less than the distance between the rolling surface 607 and the counter-rolling surface 608.

In the region of the rolling block 606, a further drum 611 is provided, which is provided on its periphery with flat deflecting mirrors 612. As the drum 611 rotates, the deflecting mirrors 612 travel through the path of rays of a laser 613, in which case the laser beam is deflected in the direction of the double filter cigarette 601 located below the rolling block 606, for which reason the rolling block 606 is provided with correspnding recesses (not shown) or passages.

A further laser located behind the laser 613, for introducing a second ring-shaped row of holes in the double filter cigarette is not shown.

At a delivery point which is not shown, double filter cigarettes 601 with a double length filter mouthpiece located therebetween, to which a tipping paper piece 604 is stuck, are placed in the grooves 603 of the rolling drum 602 such that the tipping paper piece 604 comes to lie on the rolling surface 607 of the rolling drum 602. In the region between the delivery point and the inlet end of the rolling block 606, the double filter cigarettes 601 are held by suction in the grooves 603.

The tipping paper pieces 604 are retained by means of suction openings (not shown) in the centre between the grooves 603 on the rolling surface 607 of the rolling drum 602, during the conveying operation from the delivery point to the inlet of the rolling block 606.

When they arrive below the rolling block 606, the double filter cigarettes 601 are rolled by the rolling bar 609 or rolled out of the grooves 603 receiving the latter previously, in which case the tipping paper strip 604 is guided increasingly around the double filter cigarette 601.

This sequence of movements is represented in the position of the double filter cigarette 601 designated by the reference A.

Since the grooves 603 are very flat, the double filter cigarettes 601 are also rolled by subsequent grooves 603. In the position B, the double filter cigarette 601 has rotated once completely about its axis. In this position B, the laser 613 with the afore-described means, (which are not illustrated again) is activated, in which case the pulse of rays emitted strikes the mirror 612a located in the radiation range of the laser 613 at a predetermined angle of incidence and from there is reflected at right-angles onto the double filter cigarette 601 located in position B. The intensity and duration of the laser beam is thus controlled such that it penetrates the double filter cigarette 601 completely. When the double filter cigarette 601 has reached the position C, the drum 611 and thus the mirror 612a has moved by a corresponding extent in the direction of the arrow, in which case a pulse of rays emitted by the laser 613 arrives at a flatter angle of incidence as a result of the changed position of the mirror 612a relative to the laser 613 and according to the double filter cigarette 601 drawn in full line is reflected or once more strikes the latter at right-angles and penetrates the double filter cigarette 601 completely. A further pulse of rays with an even smaller angle of incidence occurs at position D of the double filter cigarette 601-once more illustrated in broken lines. In this way, three through holes or six perforation openings are produced on the periphery of the double filter cigarette 601.

With a correspondingly modified pulse sequence of the laser 613, more holes could naturally be introduced in the double filter cigarette. When the mirror 612a leaves or when the next mirror 612b arrives in the radiation range of the laser 613, the next double filter cigarette 601 has sufficient time to terminate the wrapping operation with a tipping paper piece 604, whereby on reaching the positions B, C and D, the mirror 612b facilitates a further perforation.

WHAT WE CLAIM IS: 1. Apparatus for producing an area of desired permeability to air in wrapping material of or for rod-like articles of the tobaccoprocessing industry on a machine for producing rod-like articles, wherein the machine is provided with at least one radiation source for producing at least one beam of coherent radiation, means for pulsing the beam for the purpose of introducing a desired number of holes in selected regions of the wrapping material, and control means in operative connection with the main machine drive, for synchronising the pulsing means.

2. Apparatus according to claim 1, wherein the radiation source is a laser.

3. Apparatus according to claim 1 or 2, wherein the radiation source precedes a wrapping device and the pulsing means is synchronised by the control means in such a way that the pulse sequence for the purpose of producing a desired number of holes per unit length of a strip of the wrapping material is synchronised with the speed of the wrapping material strip supplied continuously to the wrapping device.

4. Apparatus according to claim 1 or 2, wherein the radiation source is associated with a transverse conveyor for conveying rodlike articles with their ends overhanging the conveyor so as to intersect the radiation beam, the control means being adapted to synchronise the pulsing means with the conveying cycle so that, in use, the peripheral surface of an article passing the radiation source is provided with at least one hole.

5. Apparatus according to claim 1 or 2, wherein the radiation source is associated with a rod conveyor for transporting a wrapped rod and the control means are adapted to synchronise the pulsing means with the speed of the rod such that a desired number of holes is produced in selected peripheral sections of the rod.

6. Apparatus according to any one of claims 1 to 5, including monitoring means for the area of desired permeability to air, which means, for the purpose of controlling the size of holes in this area, are in operative connection with a correcting element for varying the energy of the radiation source.

7. Apparatus according to any one of claims 1 to 5, including monitoring means for the area of desired permeability to air, which means, for the purpose of controlling the size of holes in this area, are in operative connection with a correcting element for shifting the focal point of the radiation.

8. Apparatus for producing an area of desired permeability to air in wrapping material of rod-like articles of the tobacco-processing industry on a machine for producing rod-like articles, on which the articles are conveyed at right-angles to their axes, wherein a transverse conveyor constructed as a rolling drum and an associated counter-rolling surface are adapted to be driven in opposite

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. The tipping paper pieces 604 are retained by means of suction openings (not shown) in the centre between the grooves 603 on the rolling surface 607 of the rolling drum 602, during the conveying operation from the delivery point to the inlet of the rolling block 606. When they arrive below the rolling block 606, the double filter cigarettes 601 are rolled by the rolling bar 609 or rolled out of the grooves 603 receiving the latter previously, in which case the tipping paper strip 604 is guided increasingly around the double filter cigarette 601. This sequence of movements is represented in the position of the double filter cigarette 601 designated by the reference A. Since the grooves 603 are very flat, the double filter cigarettes 601 are also rolled by subsequent grooves 603. In the position B, the double filter cigarette 601 has rotated once completely about its axis. In this position B, the laser 613 with the afore-described means, (which are not illustrated again) is activated, in which case the pulse of rays emitted strikes the mirror 612a located in the radiation range of the laser 613 at a predetermined angle of incidence and from there is reflected at right-angles onto the double filter cigarette 601 located in position B. The intensity and duration of the laser beam is thus controlled such that it penetrates the double filter cigarette 601 completely. When the double filter cigarette 601 has reached the position C, the drum 611 and thus the mirror 612a has moved by a corresponding extent in the direction of the arrow, in which case a pulse of rays emitted by the laser 613 arrives at a flatter angle of incidence as a result of the changed position of the mirror 612a relative to the laser 613 and according to the double filter cigarette 601 drawn in full line is reflected or once more strikes the latter at right-angles and penetrates the double filter cigarette 601 completely. A further pulse of rays with an even smaller angle of incidence occurs at position D of the double filter cigarette 601-once more illustrated in broken lines. In this way, three through holes or six perforation openings are produced on the periphery of the double filter cigarette 601. With a correspondingly modified pulse sequence of the laser 613, more holes could naturally be introduced in the double filter cigarette. When the mirror 612a leaves or when the next mirror 612b arrives in the radiation range of the laser 613, the next double filter cigarette 601 has sufficient time to terminate the wrapping operation with a tipping paper piece 604, whereby on reaching the positions B, C and D, the mirror 612b facilitates a further perforation. WHAT WE CLAIM IS:

1. Apparatus for producing an area of desired permeability to air in wrapping material of or for rod-like articles of the tobaccoprocessing industry on a machine for producing rod-like articles, wherein the machine is provided with at least one radiation source for producing at least one beam of coherent radiation, means for pulsing the beam for the purpose of introducing a desired number of holes in selected regions of the wrapping material, and control means in operative connection with the main machine drive, for synchronising the pulsing means.

2. Apparatus according to claim 1, wherein the radiation source is a laser.

directions at coordinated speeds such that an article guided therebetween is rotated about its own axis at a fixed locus, a radiation source is provided for producing at least one beam of coherent radiation directed at said locus, and means is provided for pulsing the beam for introducing a desired number of holes into the wrapping material over the periphery of the article.

9. Apparatus as claimed in claim 8, wherein the radiation source is associated with control means in operative connection with the main machine drive for synchronising the pulsing means.

10. Apparauts according to claim 8 or 9, wherein the source of radiation is a laser.

11. Apparatus according to any one of claims 8 to 10, wherein the counter-rolling surface is constructed as a rolling belt.

12. Apparatus according to any one of claims 8 to 11, wherein, for acting on the wrapping material of a double article, the radiation source comprises two radiation heads located side-by-side in the longitudinal direction of the article.

13. Apparatus according to any one of claims 8 to 12, wherein the radiation source is located inside the rolling drum.

14. Apparatus according to any one of claims 8 to 13, wherein the rolling belt is provided with raised rolling surfaces following each other at a distance apart, the length of which corresponds to the distance between two grooves on the rolling drum for positioning the articles before and after rolling.

15. Apparatus according to claim 11 and any one of claims 12 to 14, wherein the rolling belt is constructed as a toothed belt.

16. Apparatus according to claim 11 and any one of claims 12 to 15, wherein the rolling belt consists of a plurality of toothed belts arranged in spaced parallel relationship and between which the radiation is directed.

17. Apparatus according to any one of claims 8 to 10, wherein the counter-rolling surface is a roll body, which is provided over the periphery with alternate successive ele vations and recesses.

18. Apparatus according to claim 17, wherein the peripheral length of the ele vations corresponds to the distance between two grooves on the rolling drum for position ing the article before and after rolling of the latter.

19. Apparatus according to claims 17 or 18, wherein the roll body is provided with three rolling cylinders for engaging and rolling a double article, a radiation head being respectively associated with the central rolling cylinder of the latter, on both sides.

20. Apparatus according to claim 19, wherein the radiation heads are associated with a single laser whose beam is divided or a separate laser is associated with both sides of the central rolling cylinder.

21. Apparatus for producing an area of desired permeability to air in wrapping material of rod-like articles of the tobacco-processing industry on a machine for producing rod-like articles, on which the articles are conveyed at right-angles to their axes, comprising a transverse conveyor provided with a rolling surface and associated with a stationary counter-rolling surface such that the articles are conveyed and rotated about their own axes in use, a laser, means for guiding or deflecting the laser beam onto the articles during their conveyance and rotation, means for pulsing the beam for the purpose of producing a desired number of holes in selected regions of the wrapping material, and control means in operative connection with the machine drive for synchronising the pulsing means.

22. Apparatus according to claim 21, wherein the stationary counter-rolling surface is part of a rolling block.

23. Apparatus according to claim 21 or 22, wherein the laser or the means for guiding or deflecting the laser beam are controlled such that the articles are completely penetrated.

24. Apparatus according to any one of claims 21 to 23, wherein the transverse conveyor is constructed as a rolling drum.

25. Apparatus according to any one of claims 21 to 24, wherein the means for guiding or deflecting the laser beam comprises flat mirrors located on the periphery of a rotary drum, which mirrors deflect the incident laser beam towards the articles.

26. Apparatus according to daim 25, wherein the arrangement is such that associated with each pulse od the laser during the rolling of an article is another angle of incidence of a mirror causing the laser beam to strike the article at right-angles.

27. Apparatus for producing an area of desired permeability to air in wrapping material of or for rod-like articles of the tobaccoprocessing industry on a machine for producing rod-like articles, substantially as herein described with reference to the accompanying drawings.

28. Apparatus for producing an area of desired permeability to air in wrapping material of rod-like articles of the tobacco-processing industry on a machine for producing rod-like articles, on which the articles are conveyed at right-angles to their axes, substantially as herein described with reference to and as illustrated in the accompanying drawings.