The present invention relates to a method of transferring groups of cigarettes on a cigarette packing machine.
On cigarette packing machines, a succession of groups of cigarettes is fed along a packing path defined by a succession of conveyors, each of which is connected to at least one adjacent conveyor at a respective transfer station, where each group of cigarettes is expelled from a relative seat or pocket on the upstream conveyor along the packing path, and is transferred into a relative seat or pocket on the downstream conveyor along the packing path.
When performing the above transfer operation, both the position and configuration of the group of cigarettes being transferred are normally controlled at all times. For which purpose, the group of cigarettes to be transferred is normally gripped between movable push members normally defined by a pusher movable through or with respect to the upstream conveyor, and a counter-pusher movable through or with respect to the downstream conveyor.
In some cases, on account of the design of the seats or pockets and/or conveyors, assembly of the movable push members, and particularly the counter-pusher, is extremely difficult, and involves major mechanical complications and fairly high cost.
It is an object of the present invention to provide a method of transferring groups of cigarettes on a cigarette packing machine, designed to eliminate the aforementioned drawback.
According to the present invention, there is provided a method of transferring groups of cigarettes on a cigarette packing machine, as claimed in the attached Claims.
A non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which:
Number 1 in
Packing wheel 1 comprises a number of pockets 4, each for housing and feeding a relative group 3 of cigarettes in steps along a packing path P1 extending about an axis of rotation (not shown) of packing wheel 1 and through a transfer station 5, where packing path P1 is substantially tangent to a packing path P2, along which travel pockets 6 of a further packing wheel 7 rotating in steps about an axis (not shown) parallel to the axis of rotation (not shown) of packing wheel 1.
Each pocket 6 receives and partly houses a respective known blank 8, which is substantially rectangular and comprises a central portion 9 extending along a longitudinal axis 10, and in turn comprising a front lid panel 11 with a reinforcing flap 12; a top lid panel 13; a rear panel 14; a bottom panel 15; and a front panel 16. Blank 8 also comprises two longitudinal lateral wings 17 located on opposite sides of central portion 9, and each comprising a portion 18 extending along front lid panel 11; a portion 19 extending along rear panel 14; a portion 20 extending along front panel 16; a tab 21 extending from portion 19 towards portion 18; and a tab 22 extending from portion 19 towards portion 20.
Each pocket 6 is substantially U-shaped with its concavity facing outwards of packing wheel 7, and comprises a bottom wall 23 parallel to the axis of rotation (not shown) of packing wheel 7; and two lateral walls 24 perpendicular to bottom wall 23 and also parallel to the axis of rotation (not shown) of packing wheel 7. More specifically, the distance between lateral walls 24 is approximately equal to but no smaller than the width of central portion 9 of blank 8; lateral walls 24 and bottom wall 23 are the same length as rear panel 14 of blank 8; and the height of each lateral wall 24 is greater than the width of each longitudinal lateral wing 17 of blank 8.
Each blank 8 is fed into respective pocket 6, so that rear panel 14 contacts bottom wall 23, and the rest of central panel 9 projects outwards of pocket 6.
As it travels along packing path P2, each blank 8 is gradually folded in known manner with respect to relative pocket 6, so that it reaches transfer station 5 in a partly folded position, in which reinforcing flap 12 is folded onto front lid panel 11; portions 18 are folded squarely with respect to front lid panel 11; portion 19 of each lateral wing 17 is folded squarely with respect to rear panel 14 and contacting the inner surface of relative lateral wall 24; and tabs 21 and 22 are folded squarely with respect to portions 19 of relative lateral wings 17 and to rear panel 14, and are perpendicular to relative longitudinal axis 10. In this partly folded configuration, each blank 8 defines a cup-shaped seat 25, which is bounded by rear panel 14, tabs 21 and 22, and portion 19 of each lateral wing 17, and which receives a respective wrapped group 3 of cigarettes from packing wheel 1 at transfer station 5.
In addition to pockets 4, packing wheel 1 also comprises two coaxial disks 26 separated by a distance equal to the length of pockets 4, and supporting respective ends of each pocket 4. More specifically, each pocket 4 is positioned with its longitudinal axis 34a parallel to the axis of rotation (not shown) of wheel 1 and to the cigarettes in relative group 3 of cigarettes, and comprises two end cross members 27 and 28, which are located at the periphery of respective disks 26, and define a bottom wall 29 having a central opening 30 between disks 26. Each pocket 4 also comprises two lateral walls 31 parallel to each other and to the axis of rotation (not shown) of packing wheel 1, and projecting radially outwards of disks 26; and an outer cross member 32 connected integrally to the free edges of lateral walls 31 and facing cross member 28. Outer cross member 32 is parallel to cross member 28, is relatively narrow, measured parallel to longitudinal axis 34a of relative pocket 4, with respect to the length of pocket 4, and is divided into two equal parts by an intermediate slit 33.
Outer cross member 32 defines, on pocket 4, a tubular portion 34 coaxial with longitudinal axis 34a of pocket 4 (coincident, in use, with longitudinal axis 3a of relative group 3 of cigarettes); and a portion 35, which is aligned with tubular portion 34 along longitudinal axis 34a, is C-shaped with its concavity facing radially outwards, and defines, with tubular portion 34, a seat 36 for housing a respective group 3 of cigarettes positioned with the cigarettes parallel to the axis of packing wheel 1 and to longitudinal axis 34a. A further seat (not shown) is formed inside seat 36, is located inside C-shaped portion 35 of pocket 4, flush with outer cross member 32, houses a U-folded collar 37, and is designed so that each collar 37, when inserted inside pocket 4, is locked axially inside pocket 4, is kept outside relative seat 36, and partly surrounds group 3 of cigarettes when this is housed inside seat 36.
At transfer station 5, each pocket 4, housing a respective group 3 of cigarettes and a respective collar 37, is arrested substantially facing—along a radial axis 38, but offset laterally with respect to radial axis 38 by a distance equal to the width of outer cross member 32—a relative pocket 6, also arrested at transfer station 5. Pocket 6 houses a blank 8, the seat 25 of which is coaxial with radial axis 38 and positioned with its concavity facing relative pocket 4 and a funnel-shaped intermediate spindle 39, which is mounted inside transfer station 5 and is moved back and forth along radial axis 38 and between packing wheels 1 and 7 by a known actuating device not shown.
Spindle 39 comprises an annular, substantially rectangular frame 40 defining an inner passage 41, which is coaxial with radial axis 38 and has a rectangular cross section of approximately the same shape as and no smaller than rear panel 14 of blank 8, and substantially the same shape as the cross section of seat 25. Frame 40 has two long sides 42 crosswise to paths P1 and P2; and two short sides 43 parallel to paths P1 and P2, and one of which, located on the same side as outer cross members 32 of pockets 4, has an intermediate slit 44 of at least the same width as intermediate slits 33.
A respective tab 45 is connected integrally to the inner surface of each long side 42 of frame 40, is made of relatively elastic material, converges slightly with the other tab 45, and projects from relative long side 42 towards packing wheel 7 by a distance at most equal to the width of longitudinal lateral wings 17 of blank 8, and therefore to the depth of seat 25.
Spindle 39 moves along radial axis 38 to and from a work position (not shown), in which tabs 45 engage seat 25 defined by a blank 8 inside a pocket 6 arrested at transfer station 5, and each tab 45 is positioned contacting the inner surface of portion 19 of relative longitudinal lateral wing 17 of blank 8.
Each group 3 of cigarettes is transferred in controlled manner from a stationary pocket 4 at transfer station 5 to seat 25, defined by relative blank 8 inside the relative stationary pocket 6 at transfer station 5, by means of a gripper device 46 located at transfer station 5 and comprising two jaws 47 and 48; jaw 47 performs a first reciprocating movement in a direction 49 parallel to axis 34a, and a second reciprocating movement to and from seat 25 in a radial direction 50; and jaw 48 performs one reciprocating movement in direction 50 to and from seat 25 and at least partly through opening 30 of relative pocket 4.
More specifically, jaw 47, at rest (
Jaw 48, at rest, is located radially inwards of the stationary pocket 4 at transfer station 5, and comprises two actuating arms 58 and 59 integral with each other and parallel to radial axis 38. Actuating arm 58 is substantially coaxial with radial axis 38, and is fitted integrally, on the end facing packing wheel 7, with a plate 60, which is perpendicular to radial axis 38, is movable in direction 50 through opening 30, and has a central lateral appendix 61 parallel to radial axis 38 and which slides inside groove 54 in plate 53. Actuating arm 59 is located laterally outwards of the disk 26 opposite the one facing jaw 47 in the rest position, and is fitted integrally, on the end facing packing wheel 7, with a plate 62, which is coplanar with plate 60, moves with plate 60 in direction 50, and is substantially the same shape and size as outer cross member 32.
In actual use, when a pocket 4, housing a respective group 3 of cigarettes, and a pocket 6, housing a respective blank 8 folded to define seat 25, are arrested at transfer station 25, as shown in
At this point, when actuating arm 51 is acted on by a known push device not shown, jaw 47 is moved in direction 49, so that plate 53 engages tubular portion 34 of pocket 4, bracket 57 engages intermediate slit 33 in outer cross member 32, and plate 55 is positioned parallel to and outwards of outer cross member 32 on the side facing spindle 39. Jaw 47 continues moving in direction 49 until the group 3 of cigarettes, moving along axis 34a from an initial stop position at transfer station 5, and sliding over relative collar 37, clears tubular portion 34 of pocket 4 and is positioned in a pickup position directly facing passage 41 in spindle 39 and seat 25 along radial axis 38. In the pickup position, group 3 of cigarettes is positioned partly outwards of pocket 4 and of the disk 26 located at end cross member 27, and plate 55 is positioned substantially contacting the surface of group 3 of cigarettes facing spindle 39.
At this point, jaw 47 stops moving in direction 49, and a known push device (not shown) acts on actuating arms 58 and 59 to move jaw 48 in direction 50, so that plates 60 and 62 contact the surface of group 3 of cigarettes opposite the surface facing spindle 39, and appendix 61 engages groove 54 in plate 53 to close gripper device 46 about group 3 of cigarettes and grip it between jaws 47 and 48.
In connection with the above closing sequence of gripper device 46, it should be pointed out that, during the closing sequence, neither of jaws 47 and 48 crosses packing paths P1 and P2 in direction 50. More specifically, in the rest positions shown in
As shown in FIGS. 2 to 4, when gripper device 46 is in the closed position, the group 3 of cigarettes between jaws 47 and 48 is perfectly controlled as to both position and shape, by virtue of plate 53 being positioned contacting one of the end surfaces of group 3 of cigarettes and so keeping the relative wrapping closed.
Next, gripper device 46, still in the closed position, is moved in direction 50 along radial axis 38 towards seat 25, and, at the same time, spindle 39 is moved in direction 50 to insert tabs 45 inside seat 25. Group 3 of cigarettes, still gripped between jaws 47 and 48, therefore reaches its release position inside seat 25 by passing through spindle 39 and stopping between tabs 45, which squeeze group 3 of cigarettes transversely; and actuating arm 51 first engages slit 44 in frame 40, and then the gap between the opposite ends of tabs 21.
At this point, spindle 39 is moved back into the rest position, releasing group 3 of cigarettes in the release position inside seat 25; jaw 47 is extracted from seat 25 in direction 49, thus outwardly unfolding tabs 21 (which are folded back into the
In other words, when transferring group 3 of cigarettes, jaw 48 moves back and forth in direction 50, and jaw 47 moves along an annular path P3 comprising, as of the
Number | Date | Country | Kind |
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BO2006A000516 | Jul 2006 | IT | national |