EP0900729A1

EP0900729A1 - Method of producing rigid hinged-lid packets of cigarettes

Info

Publication number: EP0900729A1
Application number: EP98116686A
Authority: EP
Inventors: Fulvio Boldrini
Original assignee: GD SpA
Current assignee: GD SpA
Priority date: 1997-09-04
Filing date: 1998-09-03
Publication date: 1999-03-10
Also published as: CN1216731A; ITBO970531A1; IT1294184B1; ITBO970531A0

Abstract

A method of producing packets (2) of cigarettes having respective small lateral walls (31) each defined by a first and a second longitudinal portion (30; 32, 35) superimposed one on top of the other, and whereby incomplete packets (2a), having the first longitudinal portions (30) folded squarely and the second longitudinal portions (32, 35) projecting laterally and transversely with respect to the first longitudinal portions (30), are fed continuously and crosswise to the second longitudinal portions (32, 35) through a loading station (S1), and are fed parallel to the second longitudinal portions (32, 35) through a gumming and folding station (S3); and a transfer device (10), having a number of transfer pockets (58) movable through the loading station (S1), rotates the packets (2a) through 90° about an axis (B) of rotation crosswise to the first longitudinal portions (30).

Description

The present invention relates to a method of producing rigid hinged-lid packets of cigarettes.
The present invention may be used to advantage on packing machines for producing packets of cigarettes comprising a cup-shaped body and a lid coaxial with the cup-shaped body, and which are defined laterally by two small lateral walls, each defined by two longitudinal tabs gummed one on top of the other.
On known packing machines, each packet is normally formed by step-feeding a blank of packing material and a respective inner wrapping, defined by a group of cigarettes enclosed in a sheet of foil paper, in a given first direction along a given first path, and gradually folding the blank about the inner wrapping to form an incomplete packet of cigarettes, i.e. a packet in which one longitudinal tab in each pair projects laterally from a front surface of the incomplete packet, whereas the other tab in the pair is folded squarely. At this point, the incomplete packet is step-fed, crosswise to the longitudinal tabs, through a transfer station where it is engaged axially by a transfer device moving back and forth across the first path and in a second direction crosswise to the first direction to transfer the incomplete packet to a conveying device extending along a second path and through a gumming station.
On receiving the incomplete packets, the conveying device feeds them in steps, with the respective longitudinal tabs parallel to the second direction, through the gumming station where given portions of the tabs are gummed, and then through a folding station where the tabs are folded squarely and gummed to the respective already-folded tabs to form a complete packet.
The above method has several drawbacks, mainly due to the packets being transferred from the first to the second path. That is, the transfer device, despite being relatively slow as compared with the conveying devices to which it is connected, engages each packet sharply in an attempt to speed up the transfer operation. Being step-operated, however, there is a limit to the speed at which such transfer devices can be operated without incurring vibration capable of impairing the structure and reliability of the packing machine.
It is an object of the present invention to provide a method of producing rigid hinged-lid packets of cigarettes, designed to eliminate the aforementioned drawbacks.
According to the present invention, there is provided a method of producing rigid hinged-lid packets of cigarettes having respective small lateral walls, each defined by two superimposed longitudinal portions, the method comprising the steps of feeding a succession of blanks of packing material along a given path and in a given traveling direction by means of first conveying means, each blank comprising a central panel, two longitudinal lateral panels connected to the central panel and defining a first of said two longitudinal portions, two transverse end panels connected to the central panel, two front panels connected to the end panels, and, for each front panel, a further two longitudinal lateral panels defining a second of said two longitudinal portions, and each blank being fed along said path with the longitudinal lateral panels crosswise to said traveling direction; folding each blank to form a respective incomplete packet having said front panels parallel to said central panel, the respective first longitudinal portions folded squarely with respect to the central panel, and the respective second longitudinal portions coplanar with the front panels and projecting laterally with respect to the respective first longitudinal portions, the first and second longitudinal portions of each incomplete packet being arranged crosswise to said traveling direction; transferring each incomplete packet from said first conveying means to second conveying means, located along said path, by means of transfer means movable across said path and crosswise to said traveling direction to engage each incomplete packet by at least one respective end defined by a respective said end panel; rotating each incomplete packet 90° about a respective axis of rotation crosswise to said front panels to position the incomplete packet with the respective first and respective second longitudinal portions crosswise to said traveling direction; and feeding each incomplete packet, by means of said second conveying means, through a gumming and folding station located along said path, to gum a bottom surface of the respective second longitudinal portions, and to fold the second longitudinal portions squarely onto the respective first longitudinal portions to form said small lateral walls; the method being characterized by said first and second conveying means being conveying means moving continuously along said path, and by said transfer means being movable continuously, and parallel to said traveling direction, along a transfer station of said path common to the first and second conveying means.
A non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which:
Figure 1 shows a plan view, with parts in section and parts removed for clarity, of an input portion of a packing machine implementing the method according to the present invention;
Figure 2 shows a side view, with parts in section and parts removed for clarity, of an intermediate portion of a packing machine implementing the method according to the present invention;
Figure 3 shows a plan view, with parts in section and parts removed for clarity, of an output portion of a packing machine implementing the method according to the present invention;
Figure 4 shows a larger-scale plan view, with parts in section and parts removed for clarity, of a detail in Figure 1;
Figure 5 shows a side view, with parts in section and parts removed for clarity, of the Figure 4 detail;
Figure 6 shows a larger-scale view, with parts in section and parts removed for clarity, of the Figure 4 and 5 detail in a different operating position;
Figure 7 shows a larger-scale view, with parts in section and parts removed for clarity, of a detail in Figure 2.
Number 1 in Figures 1, 2 and 3 indicates as a whole a packing machine for forming rigid hinged-lid packets 2 of cigarettes (not shown) and comprising a substantially U-shaped packing path PI defined by an input branch P1 and an output branch P3 located one over the other at different levels L1 and L2, and by a curved branch P2 connecting branches P1 and P3.
Machine 1 comprises an input portion 3 (Figure 1) extending along branch P1 and defined by a packing device 4 for partially folding blanks 5 of packing material about respective inner wrappings 6 defining the content of packets 2; an output portion 7 (Figure 2) extending along branch P3 and defined by an unloading device 8 for unloading packets 2 off machine 1; and an intermediate portion 9 extending along branch P2 and defined by a transfer unit 10 for receiving incomplete packets 2a from device 4 at a loading station S1, and feeding packets 2a to device 8 at a supply station S2.
Packing device 4 comprises a pocket conveyor 11 traveling continuously at a given speed V1 in a given traveling direction D1, and in turn comprising a conveyor belt 12 looped about two pulleys defining, on belt 12, a conveying branch 13 extending at level L1 through station S1, and a number of packing pockets 14 arranged along belt 12 with a spacing K1 and traveling with conveyor 11 at speed V1 in direction D1. Device 4 also comprises a folding device 15 located along conveyor 11, upstream from station S1, and for partially folding blanks 5 about respective wrappings 6 to form incomplete packets 2a.
As shown in Figures 4, 5 and 6, each pocket 14 is U-shaped, has an open-topped inner seat 16 for receiving a respective blank 5 and respective wrapping 6, together with a respective collar 17, at a supply station (not shown) upstream from station S1, and comprises known retaining elements (not shown) for retaining blank 5 in a given prefolding configuration. Each pocket 14 also comprises a bottom wall 18 connected at the bottom to belt 12 and defined at the top by a top surface 19 defining the bottom of respective seat 16; and two lateral walls 20, which extend crosswise to direction D1, have respective inner lateral surfaces 21 facing each other and laterally defining seat 16, extend transversely outwards from bottom wall 18, and are defined vertically by respective top outer surfaces 22 crosswise to respective surfaces 21 and parallel to surface 19. Each seat 16 comprises two openings 23 and 24 crosswise to surface 19 and parallel to direction D1, and of which opening 23 permits insertion of respective wrapping 6 inside seat 16 and subsequent withdrawal of respective incomplete packet 2a from seat 16.
Blanks 5 are of the type normally used in the tobacco industry, and each comprise a central panel 25 defining a rear wall of respective packet 2; two end panels 26 and 27, which are located at opposite ends of panel 25, are connected to panel 25 by respective preformed transverse bend lines, and define respective end walls of respective packet 2; a large lateral panel 28 connected to panel 27 along a respective preformed transverse bend line and defining a bottom portion of a front wall of respective packet 2; and a further lateral panel 29 connected to panel 26 along a respective preformed transverse bend line and defining a top portion of the front wall. Each blank 5 also comprises two lateral panels 30 connected to panel 25 along respective preformed longitudinal bend lines and defining respective inner portions of respective small lateral walls 31 (Figure 3) of respective packet 2; and a further two lateral panels 32 connected to panel 28 along respective preformed longitudinal bend lines.
In said given prefolding configuration, each blank 5 is housed inside respective seat 16 with panels 25 and 30 respectively contacting bottom surface 19 and inner lateral surfaces 21 of seat 16; with panels 27 and 28 coplanar with each other and folded substantially 90° with respect to panel 25 (panel 28 projects outwards of seat 16 with respect to outer surfaces 22 of seat 16); and with panels 26 and 29 coplanar with each other and sloping downwards with respect to panel 25 and surface 19. Each lateral panel 30 comprises two tabs 33 and 34 connected to opposite ends of panel 30; and, in said given prefolding configuration, tabs 33 are folded 90° with respect to panel 30 and are located facing panel 27 inside opening 24, while tabs 34 are located to the side of opening 23 and panel 26, and are maintained parted in known manner to permit insertion of wrapping 6 and collar 17 inside blank 5 at said supply station. Finally, panel 29 comprises two substantially trapezoidal panels or tabs 35, which are connected by respective longer sides to panel 29 along respective preformed longitudinal bend lines, and define, with respective panels 32, respective outer portions of respective small lateral walls 31.
Folding device 15 comprises a first shaped plate 36 extending alongside conveying branch 13 of conveyor 11 up to station S1, and which in turn comprises a flat initial portion 37 perpendicular to branch 13 and located in front of openings 24 of seats 16 to fold panels 27 squarely with respect to respective panels 25; a helical intermediate portion 38 for squarely folding panels 28 with respect to respective panels 27, so as to fold panels 28 onto respective wrappings 6 and panels 32 onto outer surfaces 22 of respective pockets 14; and a flat end portion 39 parallel to branch 13 and for maintaining panels 28 contacting respective wrappings 6, and panels 32 contacting respective surfaces 22.
Device 15 also comprises two folding plates 40 and 41 arranged in series alongside branch 13, on the opposite side of branch 13 to plate 36; plate 40 is fitted to an endless belt 40a alongside branch 13, and travels parallel to direction D1 at a faster speed than speed V1 to fold one of tabs 34 squarely; and plate 41 is fixed and provides for squarely folding the other of tabs 34.
Device 15 also comprises a further shaped plate 42 located in series with plates 40 and 41 and in turn comprising a flat initial portion 43 substantially coplanar with branch 13 and for positioning panels 26 coplanar with bottom surfaces 19 of seats 16; a helical first intermediate portion 44 for squarely folding panels 26 onto tabs 34 to close openings 23; a flat intermediate portion 45 crosswise to branch 13 and for maintaining panels 26 contacting tabs 34 parallel to openings 23; a helical second intermediate portion 46 extending over portion 45 and outer surfaces 22 of pockets 14, and for squarely folding panels 29 onto respective wrappings 6 and tabs 35 onto surfaces 22; and a flat end portion 47 parallel to and coplanar with flat end portion 39 of plate 36, and for maintaining panels 29 contacting wrappings 6 and tabs 35 contacting surfaces 22.
Upstream from and along station S1, portions 39 and 47 of plates 36 and 42 join to form a common portion defined by a plate 48 parallel to conveying branch 13 of conveyor 11, and which cooperates with panels 28, 32 and 29 and with tabs 35 to maintain panels 28 and 29 contacting respective wrapping 6, and panels 32 and tabs 35 contacting surfaces 22. More specifically, by the time each pocket 14, in use, reaches plate 48, seat 16 contains an incomplete packet 2a, i.e. a packet 2a in which panels 30 are at right angles to panel 25, and panels 32 and tabs 35 are coplanar with one another and crosswise to panels 30.
As shown in Figures 2 and 3, unloading device 8 comprises a further pocket conveyor 49 traveling continuously at a given speed V2 in a given traveling direction D2, and which in turn comprises a conveyor belt 50 looped about two pulleys 51 (only one shown) defining on belt 50 a conveying branch 52 extending in series and at level L2 through station S2 and through a gumming and folding station S3 downstream from station S2 in direction D2 along branch P3, and a number of conveying pockets 53 arranged along belt 50 with a spacing K2 and traveling with conveyor 49 at speed V2 in direction D2.
In the example embodiment shown, speed V2 is greater than speed V1; direction D2 is parallel to direction D1; the width of belt 50, measured crosswise to direction D2, is less than the width of packets 2; and each pocket 53 is defined by a transverse projection 54 fitted integrally and crosswise to belt 50 and of a width, measured crosswise to direction D2, equal to the width of belt 50.
Transfer unit 10 comprises an orienting device 56 for receiving packets 2a from conveyor 11 at station S1 and feeding packets 2a from level L1 to level L2; and a loading device 57 located on opposite sides of device 56 and conveyor 11 at station S1 and for loading packets 2a onto device 56.
Orienting device 56 comprises a number of substantially tubular transfer pockets 58, each for receiving a respective incomplete packet 2a; and a conveying transmission 59 for rotating each pocket 58 about a horizontal first axis A1 of rotation crosswise to directions D1 and D2 to transfer packet 2a from level L1 to level L2, and about a second axis B of rotation (Figure 7) crosswise to axis A1 and to directions D1 and D2 to transfer packet 2a from a receiving position, in which pocket 58 is located at station S1 and packet 2a is oriented with panels 30 crosswise to direction D1, to a release position in which pocket 58 is located at station S2 and packet 2a is oriented with panels 30 parallel to direction D2.
As shown in Figure 7, each pocket 58 comprises two large lateral walls 60 and 61 parallel to each other and to conveying branches 13 and 52 of conveyors 11 and 49; and two small lateral walls 62 connecting walls 60 and 61 and defining, with walls 60 and 61, an inner seat 63 of pocket 58 for receiving a respective incomplete packet 2a. More specifically, seat 63 is substantially T-shaped, and comprises a central portion 64 with a substantially rectangular cross section for receiving the portion of blank 5 enclosing respective wrapping 6; and two lateral portions 65 extending on opposite sides of portion 64 and for each receiving a respective panel 32 and respective tab 35.
Each seat 63 is open at each longitudinal end to permit insertion and withdrawal of respective packet 2a; lateral portions 65 are defined by respective gaps formed between wall 60 and walls 62, and which are coplanar with each other and parallel to wall 60; and wall 61, which defines the bottom wall of central portion 64 and is located on the opposite side of portion 64 to lateral portions 65, comprises a through opening 66 extending along the whole of portion 64 and which is engaged by both belt 50 and transverse projections 54 to enable projections 54 to withdraw packet 2a from seat 63.
Conveying transmission 59 comprises, for each pocket 58, an output shaft 67, in turn comprising a respective supporting portion 68 parallel to axis B and connected to respective bottom wall 61 to the side of through opening 66, and a respective conveying portion 69 connected crosswise to portion 68 and parallel to axis A1. Transmission 59 carries shafts 67 along an annular path PA extending partially about axis A1 and partially about a further axis A2 of rotation parallel to axis A1 and located a given distance from axis A1 so as to define, along path PA, two linear portions 70 and 71 parallel to each other and to respective directions D1 and D2, and two curved portions 72 and 73 connecting portions 70 and 71. More specifically, portion 70 is located at level L1 and extends parallel to conveying branch 13 of conveyor 11; portion 71 is located at level L2 and extends parallel to and alongside conveyor 49; and portions 72 and 73 are substantially circular portions centered about respective axes A1 and A2.
Transmission 59 provides for feeding pockets 58 along portions 70 and 71 at speed V1 to enable pockets 58 to receive and release respective packets 2a, and comprises a known rotation device (not shown) common to all of shafts 67, and which rotates supporting portion 68 of each shaft 67 through 90° about respective axis B to transfer respective pocket 58 from the receiving position along portion 70, in which seat 63 is aligned with seat 16 of a packing pocket 14 and has a respective central longitudinal axis C crosswise to direction D1, to the release position in which pocket 58 is located over conveying branch 52 of belt 50 with respective axis C parallel to direction D2, and respective opening 66 is engaged in sliding manner by belt 50. More specifically, transmission 59 carries shafts 67 along path PA while maintaining portions 69 parallel to themselves at all times, and rotates portions 68 through 90° about respective axes B in a first rotation direction along portion 72, and through 90° in a second rotation direction, opposite the first, along portion 73.
Loading device 57 comprises a number of pushers 74 and counter-pushers 75 movable back and forth with respect to one another and crosswise to direction D1 to respectively engage seats 16 and 63 and unload packets 2a from seats 16 into seats 63 along station S1. More specifically, each pusher 74 and counter-pusher 75 engage a respective packet 2a by two end surfaces 76 and 77 of packet 2a respectively facing openings 24 and 23 of respective seat 16, and are movable crosswise to direction D1 as well as in direction D1 together with the respective pair of seats 16 and 63 aligned with each other along station S1.
Device 57 also comprises two endless belts 78 and 79, which are coplanar with conveying branch 13, are located on opposite sides of device 56 and conveyor 11, and have respective forward branches 81 and 80 parallel to each other and inclined with respect to direction D1. Branch 80 extends towards, until it is substantially tangent to, conveyor 11; branch 81 extends away from conveyor 11 and is substantially tangent to pockets 58 of orienting device 56; and belts 79 and 78 respectively support pushers 74 and counter-pushers 75, and provide for feeding pushers 74 and counter-pushers 75 along branch P1 of path PI.
Finally, gumming and folding station S3 comprises two elongated section elements 82 located on opposite sides of conveying branch 52 of conveyor 49, and each having an L-shaped cross section so that a horizontal flat portion 83 of each element 82 is coplanar with branch 52, and a vertical flat portion 84, crosswise to respective horizontal portion 83, is located alongside branch 52 to prevent any displacement of tabs 30 of packets 2a just withdrawn from respective pockets 58. Station S3 also comprises a control plate 85, which extends along branch P3 substantially from station S2, is located over and parallel to branch 52, and provides for maintaining panels 28 and 29 of each packet 2a just withdrawn from respective pocket 58 in contact with respective wrapping 6.
Plate 85, elements 82, and conveying branch 52 together define a channel 86 for the passage of packets 2a just withdrawn from respective pockets 58, and vertical flat portions 84 of elements 82 are interrupted downstream from two known gumming rollers 87, which form part of station S3, are located on opposite sides of channel 86, and provide for gumming respective bottom surfaces 88 of panels 32 and tabs 35 projecting laterally, in use, from portions 84 along the portion extending between station S2 and rollers 87.
Finally, station S3 also comprises two helical plates 89 formed by gradually forming respective longitudinal lateral portions of plate 85 into a given spiral, and which provide for squarely folding panels 32 and tabs 35 onto respective panels 30 to complete the folding of packets 2a and form respective small lateral walls 31 of packets 2.
Operation of packing machine 1 will now be described with reference to one blank 5 in the prefolding position and to a respective wrapping 6, both housed inside a respective packing pocket 14 fed continuously by pocket conveyor 11 in direction D1 at speed V1.
Along branch P1 of path PI, blank 5 is folded gradually by plates 36 and 42 as described previously to form, shortly upstream from end plate 48 in direction D1, a packet 2a housed inside respective seat 16 with panels 30 contacting inner lateral surfaces 21, panel 25 contacting upper bottom surface 19, panels 26 and 27 facing respective openings 23 and 24 and retained by portions 39 and 47 of plates 36 and 42, panels 32 and tabs 35 contacting upper outer surfaces 22 of walls 20, and panels 25 and 29 compressed between wrapping 6 and plate 48. Packet 2a is thus fully retained inside pocket 14, and, at station S1 where portions 39 and 47 of plates 36 and 42 are interrupted, is immediately engaged by a pusher 74 and respective counter-pusher 75, which travel parallel to themselves in direction D1 at speed V1 and at the same time are moved crosswise to direction D1 by respective belts 79 and 78.
More specifically, when packet 2a is fed by pocket 14 to station S1, seat 16 of pocket 14 is aligned longitudinally with seat 63 of a pocket 58, i.e. with outlet opening 24 of seat 16 directly facing central portion 64 of seat 63, and with upper surfaces 22 of seat 16 coplanar with lateral portions 65 of seat 63. Once pockets 14 and 58 are aligned, a pusher 74 and respective counter-pusher 75 - the latter by now inside seat 63 - engage end surfaces 76 and 77 of packet 2a and, moving crosswise to direction D1, transfer packet 2a from seat 16 into seat 63 so that panels 32 and tabs 35 are inserted inside lateral portions 65 of seat 63, inside which packet 2a is retained fully on all sides.
At this point, pocket 58, after traveling along portion 70 of path PA with panels 32 of packet 2a crosswise to direction D1, and after being released by pusher 74 and respective counter-pusher 75, maintains the same orientation along portion 70 until respective shaft 67 travels along portion 72, along which said orienting device rotates supporting portion 68 through 90° about respective axis B and with respect to conveying portion 69 to position panels 32 inside pocket 58 parallel to direction D2, i.e. crosswise to direction D1. The end portion of portion 72 of branch P2 is so formed that pocket 58, on gradually approaching belt 50, permits insertion of belt 50 inside opening 66, and, as panel 25 contacts upper surface 55 of conveying branch 52, i.e. as pocket 58 begins traveling along portion 71 of branch P3, a transverse projection 54 collides with surface 76 of packet 2a at a speed V2 greater than the traveling speed V1 of packet 2a.
The difference in speed between pocket 58 and projection 54 provides for extracting packet 2a longitudinally from seat 63, and for inserting packet 2a inside a conveying pocket 53 and inside channel 86 the instant packet 2a is withdrawn fully from seat 63. Along channel 86, packet 2a is retained laterally by vertical flat portions 84 of elements 82, by control plate 85, and by horizontal flat portions 83 of elements 82, and is retained at the rear by projection 54, which pushes packet 2a in direction D2. As packet 2a travels through station S3, the bottom surfaces 88 of panels 32 and tabs 35 are gummed by gumming rollers 87, and, immediately downstream from rollers 87, panels 32 and tabs 35 are folded squarely onto respective panels 30 to form small lateral walls 31 of packet 2 and so obtain a complete packet 2.
Machine 1 as described above therefore provides for continuously forming rigid hinged-lid packets 2 of cigarettes, and for straightforward rapid transfer of incomplete packets 2a from one conveyor to the other with no step-operated devices and, above all, without ever releasing packets 2a in any way before they are finally closed.

Claims

A method of producing rigid hinged-lid packets of cigarettes having respective small lateral walls (31), each defined by two superimposed longitudinal portions (30; 32, 35), the method comprising the steps of feeding a succession of blanks (5) of packing material along a given path (PI) and in a given traveling direction (D1, D2) by means of first conveying means (11), each blank (5) comprising a central panel (25), two longitudinal lateral panels (30) connected to the central panel (25) and defining a first of said two longitudinal portions (30; 32, 35), two transverse end panels (26, 27) connected to the central panel (25), two front panels (28, 29) connected to the end panels (26, 27), and, for each front panel (28, 29), a further two longitudinal lateral panels (32, 35) defining a second of said two longitudinal portions (30; 32, 35), and each blank being fed along said path (PI) with the longitudinal lateral panels (30; 32, 35) crosswise to said traveling direction (D1, D2); folding each blank (5) to form a respective incomplete packet (2a) having said front panels (28, 29) parallel to said central panel (25), the respective first longitudinal portions (30) folded squarely with respect to the central panel (25), and the respective second longitudinal portions (32, 35) coplanar with the front panels (28, 29) and projecting laterally with respect to the respective first longitudinal portions (30), the first and second longitudinal portions (30; 32, 35) of each incomplete packet (2a) being arranged crosswise to said traveling direction (D1, D2); transferring each incomplete packet (2a) from said first conveying means (11) to second conveying means (49, 56), located along said path (PI), by means of transfer means (57) movable across said path (PI) and crosswise to said traveling direction (D1, D2) to engage each incomplete packet (2a) by at least one respective end (76, 77) defined by a respective said end panel (26, 27); rotating each incomplete packet (2a) 90° about a respective axis (B) of rotation crosswise to said front panels (28, 29) to position the incomplete packet (2a) with the respective first and respective second longitudinal portions (30; 32, 35) crosswise to said traveling direction (D1, D2); and feeding each incomplete packet (2a), by means of said second conveying means (49, 56), through a gumming and folding station (S3) located along said path (PI), to gum a bottom surface (88) of the respective second longitudinal portions (32, 35), and to fold the second longitudinal portions (32, 35) squarely onto the respective first longitudinal portions (30) to form said small lateral walls (31); the method being characterized by said first and second conveying means (11, 56, 49) being conveying means moving continuously along said path (PI), and by said transfer means (57) being movable continuously, and parallel to said traveling direction (D1, D2), along a transfer station (S1) of said path (PI) common to the first and second conveying means (11, 56, 49).
A method as claimed in Claim 1, characterized in that said first conveying means (11) comprise a number of packing pockets (14) movable along said path (PI) and each containing a respective blank (5) and a respective inner wrapping (6) defining the content of a respective packet (2) of cigarettes; each packing pocket (14) having respective supporting means (22) for supporting the second longitudinal portions (32, 35) of the respective incomplete packet (2a) in a position coplanar with the respective front panels (28, 29), and being engaged longitudinally by said transfer means (57).
A method as claimed in Claim 2, characterized in that said second conveying means (49, 56) comprise a respective number of transfer pockets (58) alignable longitudinally with the packing pockets (14) along said transfer station (S1), and engageable longitudinally by said transfer means (57) to receive respective incomplete packets (2a) from the packing pockets (14).
A method as claimed in Claim 3, characterized in that said transfer pockets (58) each comprise a respective retaining seat (63) for a respective incomplete packet (2a); the retaining seat (63) having a central portion (64), and two lateral portions (65) on opposite sides of the central portion (64) to receive and maintain said second longitudinal portions (32, 35) coplanar with the respective front panels (28, 29).
A method as claimed in Claim 3 or 4, characterized in that, along said path (PI), said first conveying means (11) define an input branch (P1), and said second conveying means (49, 56) define an output branch (P3) and a connecting branch (P2) connecting the input and output branches (P1, P3); the input and output branches (P1, P3) being parallel to each other and to said traveling direction (D1, D2); and the input branch (P1) and the output branch (P3) extending respectively through said transfer station (S1) and said gumming and folding station (S3).
A method as claimed in Claim 5, characterized in that said transfer pockets (58) are movable continuously along said input, output and connecting branches (P1, P2, P3), and rotate 90° about said axis (B) of rotation at least along the connecting branch (P3).
A method as claimed in Claim 5 or 6, characterized in that said second conveying means (49, 56) comprise extracting means (54) movable continuously along said output branch (P3) to engage said transfer pockets (58) and extract the incomplete packets (2a) from the transfer pockets (58), and to feed the incomplete packets (2a) through said gumming and folding station (S3).
A method as claimed in any one of the foregoing Claims from 4 to 7, characterized in that said transfer means (57) comprise a number of pusher elements (74) and respective counter-pusher elements (75) movable parallel to themselves and to said traveling direction (D1, D2), and movable crosswise to said traveling direction (D1, D2) to longitudinally engage said packing pockets (14) and said transfer pockets (58) respectively.
A method as claimed in Claim 8, characterized in that each pair of pusher and counter-pusher elements (74, 75) engages a respective incomplete packet (2a) by respective ends (76, 77) to transfer the incomplete packet (2a) from the respective packing pocket (14) to the respective transfer pocket (58).
A method as claimed in Claim 9, characterized in that, during transfer of an incomplete packet (2a) from a packing pocket (14) to a respective transfer pocket (58), said supporting means (22) of the packing pocket (14) and said lateral portions (65) of the retaining seat (63) are coplanar and aligned longitudinally with one another; said second longitudinal portions (32, 35) being detached gradually from the respective supporting means (22) and being gradually engaged inside the respective lateral portions (65).
A method as claimed in any one of the foregoing Claims from 5 to 10, characterized in that said input branch (P1) and said output branch (P3) extend on a given first and a given second level (L1, L2) respectively; the first level (L1) being higher than the second level (L2); and said connecting branch (P2) being substantially circular.