CONTINUOUS CIGARETTE PACKING MACHINE 2298178 The present invention relates
to a continuous cigarette packing machine.
Patent DE-A-35 27 741 relates to a cigarette packing machine wherein a pocket conveyor device is f ed past the output of a cigarette f eedbox by which it is supplied successively with groups of cigarettes which are then fed to respective folding spindles fed along an annular path by a wrapping wheel rotating about an axis. As it travels along said path, each spindle is supplied by a f eed device with a respective sheet of wrapping material, which is f olded about the spindle to f orm. a tubular wrapping.
The above packing machine is a substantially discontinuous type, i.e. wherein a step drive device operates both the pocket conveyor and the device f or feeding the sheets of wrapping material onto the wrapping wheel, while a continuous drive device imparts a substantially constant angular speed to the wrapping wheel. The pocket conveyor travels in steps at the station in which the groups are transf erred to it from the f eedbox, whereas, being connected to the wrapping wheel, the pocket conveyor travels continuously at the station in which the groups are transferred from it to the wrapping wheel.
Known packing machines of the above type present several drawbacks, mainly due to the combined intermittent and continuous movements involved, which result in severe vibration of the machine and, hence, a high noise level and a relatively poor degree of reliability.
It is an object of the present invention to provide a packing machine featuring a wrapping wheel rotating at substantially constant speed, but designed to overcome the aforementioned drawbacks.
According to the present invention, there is provided a continuous cigarette packing machine comprising a f irst wrapping conveyor; a succession of wrapping spindles fitted to the first conveyor and movable continuously with the first conveyor along a first given path; a continuously-moving second feed conveyor for f eeding a group of cigarettes to each said spindle at a first transfer station along said first path; and a f eed device f or f eeding each said spindle with a sheet of wrapping material along a second path and at a second transfer station along said f irst path; characterized in that said second path extends crosswise to and through the f irst path at the second transfer station; the f eed device comprising continuous ly-moving conveying means f or f eeding a succession of sheets of wrapping material to said second transfer station in time with the spindles, and in such a manner that each sheet crosses the first path between two successive spindles, and an intermediate portion of the sheet is engaged by the rear spindle of said two successive spindles; a retaining member, fitted to the first conveyor and associated with each spindle, cooperating with the intermediate portion of the sheet to retain it on said rear spindle and on the first conveyor.
Two non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, in which:
Figure 1 shows a side view, with parts in section and parts removed for clarity, of a first preferred embodiment of the machine according to the present invention; Figure 2 shows an axial section of a detail in Figure 1; Figures 3 to 8 show a detail of Figure 1 in various operating positions; Figure 9 shows a side view, with parts in section and parts removed for clarity, of a second preferred embodiment of the machine according to the present invention; Figures 10 to 15 show a detail of Figure 9 in various operating positions.
Number 1 in Figures 1 and 2 indicates a continuous packing machine f or packing groups 2 of cigarettes 3, and f or f orming, about each group 2 and from a sheet 4 of wrapping material, preferably foil, a tubular cup-shaped wrapping 5 (Figure ac) presenting an end wall Sa crosswise to cigarettes 3.
Machine 1 comprises a supporting f rame 6; a drive shaft 7 extending transversely from frame 6 and presenting a substantially horizontal axis 8; and a wrapping wheel 9 in turn comprising a number of peripheral pockets or spindles 10 equally spaced about axis 8. Wheel 9 is f itted to shaft 7 so as to rotate anticlockwise (in Figure 1) about axis 8 at substantially constant angular speed, and to feed spindles 10 along a substantially circular path P.
Wheel 9 also comprises a central drum 11 in turn comprising a central sleeve 12 fitted to shaft 7, and two annular, substantially circular flanges 13, 14 extending outwards from opposite ends of sleeve 12, and of which flange 14 is fitted along its outer periphery with spindles 10 projecting from flange 14 towards flange 13. Drum 11 also comprises a first and second tubular appendix 15, 16 extending coaxially with axis 8. More specifically, appendix 15 presents a radius smaller than that of appendix 16 and substantially equal to that of flange 13, is connected integral at one end with flange 14, and presents a free end portion extending inside appendix 16 which, on the end facing flange 14, presents an inner annular flange 17 for connecting appendix 16 to an intermediate point of appendix 15.
Machine 1 also comprises two pocket conveyors 18, 19, in turn comprising respective belts 20, 21 looped about respective pulleys 22, 23 fitted respectively to appendix 15 and flange 13. More specifically, conveyor 18 presents a number of pockets 24 for transporting respective groups 2, and which are aligned with relative spindles 10 along the arc of tangency between belt 20 and pulley 22. Similarly, conveyor 19 presents a number of pockets 25 aligned with relative spindles 10 along the arc of tangency between belt 21 and pulley 23.
Machine 1 also comprises a feed device 26 for supplying sheets 4, and which is located in a fixed position outside wheel 9, and provides for successively and continuously feeding sheets 4, duly spaced, along a path F crosswise to path P and extending across path P at a station 27 at which sheets 4 are fed onto wheel 9. More specifically, feed device 26 comprises two counter-rotating conveyor belts 26a facing each other, and the transportation branches of which are positioned f acing each other to grip sheets 4 and f eed them along path F onto wheel 9 in a substantially radial direction. Conveyors 26a are operated by a known drive device (not shown) in time with wheel 9, and in such a manner that each sheet 4 is fed radially onto wheel 9, and the front portion of sheet 4 penetrates inside the gap between a respective pair of adjacent spindles 10 before the rear spindle 10 in the pair contacts sheet 4.
Wheel 9 comprises a transfer unit 28 for successively transferring groups 2 from pockets 24 to spindles 10 at a first transfer station S1, and groups 2 and respective wrappings 5 from spindles 10 to pockets 25 at a second transfer station S2; a folding unit 29, for each spindle 10, fitted to flange 14 and rotating about axis 8 together with wheel 9; and a further folding unit 30 fixed along the periphery of wheel 9 downstream from station 27, and defining a folding station S3 along path P.
For each spindle 10, unit 28 comprises a pusher 31 and a counter-pusher 32 aligned with each other and with respective spindle 10 on either side of the spindle, and respectively fitted to flange 17 and to flanges 13 and 14 so as to rotate with wheel 9 about axis 8. Each pusher 31 comprises a respective rod 33 parallel to axis 8 and presenting a respective tappet roller 34 which positively engages a groove 35 of a cylindrical cam 36 fitted in rotary manner to shaft 7 and inside appendix 16, and so formed as to move pusher 31 axially to and from a position in which it engages pocket 24 and spindle 10. Each counter-pusher 32 comprises a respective rod 37 parallel to axis 8 and presenting a respective tappet roller 38 which positively engages a groove 39 of a cylindrical cam 40 fitted in rotary manner to shaft 7 and inside appendix 15, and so formed as to move counter-pusher 32 axially to and from a position in which it engages pocket 25. Cam 40 presents a f ront wall f acing f lange 14, and which f orms a f ace cam 41 with two annular grooves 42, 43 extending about axis 8, and the function of which is described later on.
Folding unit 29 comprises a retaining member 44, in turn comprising a right-angle rocker arm 45 located between f langes 13 and 14 and f itted to f lange 14 by a hinge pin 46 fitted through a respective hole 47 formed in flange 14. Rocker arm 45 comprises two arms 48, 49 substantially perpendicular to each other and fitted on their respective free ends with a pad 50 and a tappet roller 51. Pad 50 cooperates with respective spindle 10 to retain the intermediate portion of a respective sheet 4 on the outer surface of the front wall 52 of the rear spindle 10 in the pair between which sheet 4 is f ed by device 26; while roller 51 positively engages groove 43 of cam 41.
Folding unit 29 also comprises an articulated parallelogram device 53, in turn comprising a connecting rod 54 positioned substantially radially in relation to wheel 9, and two cranks 55, 56 pivoting respectively at 57 and 58 on flange 14, and for supporting and guiding connecting rod 54. Crank 55 f orms one arm of a rocker arm 59, the second arm 60 of which extends on the opposite side of connecting rod 54 to crank 55, and is fitted on its free end with a tappet roller 61 positively engaging groove 42 of cam 41. Connecting rod 54 projects beyond the pivot connecting it to crank 56, and is fitted, on its free end facing respective spindle 10, with a substantially L-shaped, comb-like folding member 62 which cooperates with respective spindle 10 to fold sheet 4 onto the spindle.
Folding unit 30 comprises two comb-like plates 63 located in a f ixed position, one outwards of the other, immediately downstream from station 27, and defining a channel 64 extending along a portion of path P and of 10 together with respective sheets 4. Plates 63 provide for f olding sheet 4 in a U inside channel 64 and onto the two lateral walls 63a (Figure 3b) crosswise to wall 52 of respective spindle 10, so that sheet 4 presents two parallel free edges 65, 66 (Figure 4b) projecting from the rear of spindle - 10, and an end 67 (Figure 4b) projecting axially from spindle 10 and facing flange 13.
Folding unit 30 also comprises a folding device 68 located radially outwards of outer plate 63, and presenting a number of combs 69 (two in the example shown), each of which is positioned substantially radially in relation to axis 8, penetrates inside channel 64 through outer plate 63, and moves along channel 64 in contact with the rear end of a respective spindle 10 also traveling along channel 64. Combs 69 are moved successively along channel 64 by a pair of conveyor belts 70 looped about respective pulleys 71 and supporting combs 69 by means of respective pins 72 parallel to the axis of pulleys 71 and so connected to combs 69 as to keep them constantly parallel to such a width as to permit the passage of "spindles themselves.
Folding unit 30 also comprises a further folding device 73 located along path P, downstream from channel 64, to the side of wheel 9 on the f lange 13 side, and which provides f or f olding end 67 of each sheet 4 to f orm, a respective cup-shaped wrapping 5, and comprises, in succession, a folding wheel 74, a fixed folding plate 75, and two known folding screws 76, 77.
In actual use, conveyors 18, 19 and wheel 9 f eed respective pockets 24, 25 and spindles 10 continuously and at the same surf ace speed along path P, so that a pocket 24 and a respective pocket 25 and spindle 10 are maintained constantly aligned.
operation of machine 1 will now be described with reference to one spindle 10, and as of the instant in which spindle 10, together with respective pockets 24 and 25, begins traveling along a portion of path P common to the path of pockets 24 and extending along station S1.
At this point, a transfer unit 28 transfers a group 2 of cigarettes 3 from the relative pocket 24 into spindle 10, while device 26 feeds a sheet 4 to station 27 so that the intermediate, substantially central portion of sheet 4 is positioned crosswise to path P.
As spindle 10 intercepts sheet 4, retaining member 44 is moved backwards in relation to wheel 9 by respective roller 51, and moves respective pad 50 up to spindle 10 so as to retain said central portion of sheet - 10 4 on wall 52 of spindle 10 (Figures 3a, 3b). At this point, wheel 9 moves spindle 10, together with respective pad 50, along channel 64 to fold sheet 4 in a U onto walls 63a of spindle 10 (Figures 4a, 4b), while folding device 68 moves respective comb 69 to fold the f ree edge 66 of sheet 4 (Figures 5a, 5b) squarely onto the rear wall 52a, crosswise to walls 63a, of spindle 10.
once edge 66 is folded, comb 69 withdraws from channel 64, which is then engaged by respective f olding member 62 activated by respective connecting rod 54 in turn activated by respective roller 61. Folding member 62 folds edge 65 about spindle 10 and onto edge 66 to form a tubular wrapping 78 (Figures 6a, 6b) fully surrounding spindle 10, and projecting from spindle 10 towards flange 13 with two facing radial tabs 79 and two facing tabs 80 perpendicular to tabs 79.
At this point, wheel 9 feeds spindle 10, with folding member 62 and pad 50, through together folding device 73. More specifically, wheel 74 and plate 75 fold tabs 79 squarely towards each other (Figures 7a, 7b, 7c); and screws 76 and 77 then fold tabs 80 squarely towards each other to close wrapping 78 and form wrapping 5 (Figures Sa, 8b, 8c).
At this point, folding member 62 and pad 50 release spindle 10 to enable transfer unit 28 to transfer wrapping 5, together with group 2, from spindle 10 into relative pocket 25.
The variation in Figures 9 to 15 relates to a wheel 81 similar to wheel 9, except that outer plate 63 and channel 64 are dispensed with, and folding device 68 is replaced by a folding roller 82 located along the periphery of wheel 81 upstream from wheel 74, and by a f ixed plate 83 tangent to the periphery of wheel 81 at wheel 74.
on wheel 81, each sheet 4 is fed to station 27 so that an intermediate portion close to the rear end of the sheet is intercepted by spindle 10, and wrapping 78 is therefore closed onto the part of spindle 10 facing outwards in relation to wheel 81. More specifically, edge 66 is positioned substantially contacting spindle 10 (Figures 11, 12) and is stabilized by plate 83 (Figures 13, 14), while edge 65, following operation of folding member 62 (Figure 12), is positioned radially in relation to wheel- 81, and is folded onto spindle 10 (Figures 14, 15) by roller 82, which is mounted for rotation about an axis parallel to axis 8, and presents a projecting sector 84 cooperating with edge 65 to fold it as described.