ITBO20120115A1 - UNIT AND METHOD OF FEEDING OF A BLEED OF A DRAWER OF A CONVEYOR. - Google Patents

Description

DESCRIPTION

of the industrial invention entitled:

"Unit and method of feeding a blank to a drawer of a conveyor."

TECHNIQUE SECTOR

The present invention relates to a unit and to a method of feeding a blank to a drawer of a conveyor. The present invention finds advantageous application in feeding a blank for a packet of cigarettes to a wrapping conveyor of a cigarette packing machine, to which the following description will make explicit reference without thereby losing generality.

ANTERIOR ART

Some packets of cigarettes require the use of a blank with external panels which are arranged at the ends of the blank and must be folded 180 ° and then glued to corresponding internal panels. In this situation, it has been proposed to preliminarily fold the outer panels of the blank before coupling the blank to the group of cigarettes (i.e. before folding the blank around the group of cigarettes) by means of a preliminary wrapping unit.

A known preliminary wrapping unit comprises a wrapping conveyor which is provided with a plurality of wrapping drawers, each of which is adapted to house a blank for advancing the blank along a wrapping path extending between an insertion station and a transfer station. In correspondence with the insertion station, a hopper is provided, which houses a stack of blanks and cyclically feeds the blanks from a lower extraction opening towards the wrapping drawers of the wrapping conveyor; in particular, each blank arranged in correspondence with the lower extraction opening of the hopper is picked up by a suction head which moves vertically with an alternative movement and is placed on an underlying wrapping drawer of the wrapping conveyor which is stationary in the insertion station in alignment with the lower extraction opening. At least one gumming device is coupled to the wrapping conveyor which is arranged along the wrapping path downstream of the insertion station and deposits glue on at least one external panel; moreover, at least one folding device is coupled to the wrapping conveyor which is arranged downstream of the gumming device along the wrapping path and folds the previously rubberized outer panel to overlap and glue the outer panel to a corresponding inner panel.

According to a preferred embodiment, in the wrapping drawer, the blank is arranged in such a way that at least one outer panel of the blank protrudes from the wrapping drawer; in this way it is possible to simplify the subsequent folding operation of the external panel since, if the external panel protrudes from the drawer, the external panel itself can easily be folded by fixed folding profiles during the advancement of the wrapping drawer along the wrapping path without the need for any mobile folder.

However, it has been observed that in known preliminary wrapping units of the type described above, the folding of the outer panels does not always have the desired precision; moreover, it has been observed that in known preliminary wrapping units of the type described above, the preliminary wrapping unit stops relatively frequently due to flooding caused by an incorrect mechanical interaction between the external panel that protrudes from the drawer and the gumming device and / or the folding device.

DESCRIPTION OF THE INVENTION

The object of the present invention is to provide a unit and a method for feeding a blank to a drawer of a conveyor, which unit and method of feeding are free from the drawbacks described above and, in particular, are simple and economical to make.

According to the present invention, a unit and a method of feeding a blank to a drawer of a conveyor are provided, according to what is claimed in the attached claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described with reference to the attached drawings, which illustrate a non-limiting example of embodiment, in which:

- Figure 1 is a perspective view, schematic and with parts removed for clarity of a preliminary wrapping unit of a cigarette packing machine in which a wrapping conveyor receives blanks in succession by means of a feeding unit made in accordance with the present invention; Figure 2 is a plan view of a blank which is fed to the wrapping conveyor of Figure 1 by the feeding unit;

Figure 3 is a side view, schematic and with parts removed for clarity of the power supply unit of Figure 1;

- Figures 4 and 5 are two perspective views, schematic and with parts removed for clarity of the power supply unit of Figure 1; And

- figure 6 is a sectional view, schematic and with parts removed for clarity of a guide device of the power supply unit of figure 1.

PREFERRED FORMS OF IMPLEMENTATION OF THE INVENTION In figure 1, the number 1 indicates, as a whole, a preliminary wrapping unit which is part of a cigarette packing machine and performs a preliminary folding of a blank 2 (better illustrated in figure 2) which is intended for making a pack 1 of cigarettes.

According to what is illustrated in Figure 2, the blank 2 has internal panels 3, external panels 4 arranged at the left end of the internal panels 3, and an external panel 5 arranged at the right end of the internal panels 3; in other words, the external panels 4 and 5 are arranged at opposite ends of the internal panels 3. The preliminary wrapping unit 1 folds 180 ° and glues part of the external panels 4 and 5 to the corresponding internal panels 3.

According to what is illustrated in Figure 1, the wrapping unit 1 comprises a wrapping conveyor 6 which advances step by step (that is, alternating cyclical motion phases and resting phases) along a wrapping path P. The wrapping conveyor 6 is provided with a plurality of wrapping drawers 7, each of which is adapted to house a blank 2 to advance the blank 2 along the wrapping path P which extends between an insertion station S1, in in which a feeding unit 8 inserts the blanks 2 in succession into the wrapping drawers 7, and a transfer station S2, in which the partially folded blanks 2 are extracted from the wrapping drawers 7 and then advanced towards a subsequent wrapping unit. The wrapping conveyor 6 is a belt and comprises a flexible belt 9 which carries the wrapping drawers 7 and is closed in a loop around two end pulleys 10.

The feeding unit 8 is arranged in correspondence with the insertion station S1 and comprises a hopper 11, which houses a stack of blanks 2 and has a lower extraction opening facing the wrapping drawer 7 of the wrapping conveyor 6 which is parked in the insertion station S1. Furthermore, according to what is illustrated in Figure 3, the feeding unit 8 comprises a transfer device 12 which picks up each blank 2 arranged in correspondence with the lower extraction opening of the hopper 11 and then inserts the blank 2 into an underlying drawer 7 of wrapping the wrapping conveyor 6 which is stationary in the insertion station S1 in alignment with the lower extraction opening. The transfer device 12 comprises a plurality of suction gripping heads 13 which are mounted on a common support which reciprocates along a vertical transfer direction D which is perpendicular to the wrapping path P. In other words, the suction gripping heads 13 of the transfer device 12 are alternatively movable along the transfer direction D between the insertion station S1 and a withdrawal station which is arranged above the insertion station S1 and consists of the lower extraction opening of the hopper 11.

As illustrated in Figure 2, a gumming device 14 is coupled to the wrapping conveyor 6 which is arranged along the wrapping path P downstream of the insertion station S1 and deposits glue on some external panels 4 and 5 of each blank. 2; furthermore, a folding device 15 is coupled to the wrapping conveyor 6 which is arranged downstream of the gumming device 14 along the wrapping path P and folds some external panels 4 and 5 of each blank 2 previously gummed to overlap by 180 ° and glue said external panels 4 and 5 on corresponding internal panels 3.

As illustrated in Figures 3 and 5, in each wrapping drawer 7, the corresponding blank 2 is arranged in such a way that the outer panels 4 and 5 of the blank 2 (which constitute opposite ends of the blank 2) protrude from opposite sides. of the wrapping drawer 7; in this way it is possible to simplify the subsequent folding operation of the external panels 4 and 5 since, if the external panels 4 and 5 protrude from the drawer 7, the external panels 4 and 5 themselves can easily be folded by fixed folding profiles during the advancement of the wrapping drawer 7 along the wrapping path P without the need for any mobile folder. As illustrated in figures 3-6, the feeding unit 1 comprises two guiding devices 16, which are arranged in the insertion station S1 in a fixed position on opposite sides of the parked drawer 7 and maintain the corresponding external panels 4 and 5 of the blank 2 (which constitute opposite ends of the blank 2) which protrude from the drawer 7 when the conveyor 6 moves the drawer 7 out of the insertion station S1. In other words, each guiding device 16 is arranged in a fixed position immediately downstream of the insertion station S1 along the wrapping path P of the conveyor 6 and keeps the corresponding external panels 4 or 5 of the blank 2 in a predetermined position cantilevered from the drawer 7 when the conveyor 6 moves the drawer 7 out of the insertion station S1.

Each guiding device 16 comprises an upper guiding element 17 which is arranged above the wrapping path P of the conveyor 6 and prevents the corresponding outer panels 4 or 5 of the blank 2 which protrude from the drawer 7 from rising with respect to the path P wrapping of the conveyor 6 when the conveyor 6 moves the drawer 7 out of the insertion station S1. Furthermore, each guiding device 16 comprises a lower guiding element 18 which is arranged under the wrapping path P of the conveyor 6 and prevents the corresponding outer panels 4 or 5 of the blank 2 which protrude from the drawer 7 from lowering with respect to the wrapping path P of the conveyor 6 when the conveyor 6 moves the drawer 7 out of the insertion station S1. In each guiding device 16, the upper guiding element 17 and the lower guiding element 18 are arranged above and below the wrapping path P of the conveyor 6 and define a slot 19 through which the corresponding panels 4 pass or 5 external parts of the blank 2 which protrude from the drawer 7 when the conveyor 6 moves the drawer 7 out of the insertion station S1.

According to a preferred embodiment better illustrated in Figure 6, in each guide device 16 the guide elements 17 and 18 have a triangular shape towards the insertion station S1 to give a progressively decreasing dimension to an inlet portion of the slot 19 ( that is, a `` funnel '' shape) so as to have a self-centering function of the corresponding external panels 4 or 5 of the blank 2 which protrude from the drawer 7.

According to a preferred embodiment illustrated in Figures 4 and 5, each guide device 16 is shaped like a `` U '', i.e. the two upper and lower guide elements 17 and 18 are shaped like a `` U '' to define each other a slot 19 arranged downstream of the insertion station S1 along the wrapping path P of the conveyor 6 and a slot 19 arranged upstream of the insertion station S1 along the wrapping path P of the conveyor. It is evident that the slot 19 arranged upstream of the insertion station S1 along the wrapping path P of the conveyor is â € œ uselessâ €, since upstream of the insertion station S1 the packing drawers 7 are devoid of blanks 2 However, the U-shape of the guiding devices 16 which confers symmetry to the guiding devices 16 themselves makes it possible to simplify and make more robust the fastening of the guiding devices 16 on the frame of the packing machine.

The operation of the feeding unit 8 for feeding a blank 2 to a wrapping drawer 7 of the wrapping conveyor 6 is described below.

Initially, the wrapping conveyor 6 advances one step along the wrapping path P to bring the wrapping drawer 7 into the insertion station S1 and then stops for a certain time interval to keep the wrapping drawer 7 parked in the station. S1 insertion. When the wrapping drawer 7 is parked in the insertion station S1, the suction gripping heads 13 of the transfer device 12 (which were initially arranged under the wrapping drawer 7 as illustrated in Figures 3 and 4) move together with reciprocating motion along the transfer direction D to pick up the blank 2 from the withdrawal station which is arranged above the insertion station S1 and consists of the lower extraction opening of the hopper 11 and then insert the blank 2 into the drawer 7 of wrapping that is parked in the insertion station S1. When the blank 2 is inserted into the wrapping drawer 7 parked in the insertion station S1, the outer panels 4 and 5 of the blank 2 (which constitute opposite ends of the blank 2) protrude from opposite sides of the wrapping drawer 7 (as shown in Figures 3 and 5).

Once the blank 2 has been inserted into the wrapping drawer 7 parked in the insertion station S1, the wrapping conveyor 6 advances a further step along the wrapping path P to bring out the wrapping tray 7 carrying the blank 2 as soon as it is fed by the insertion station S1 and then to enter another drawer 7 of empty wrapping into the insertion station S1. When the wrapping drawer 7 carrying the blank 2 exits from the insertion station S1, at least part of the outer panels 4 and 5 of the blank 2 (which constitute opposite ends of the blank 2) enter the corresponding slots 19 of the guide devices 16 (the Entry of the external panels 4 and 5 into the slots 19 is facilitated by the â € œfunnelâ € shape of the entrance portions of the slots 19).

It has been observed that in the absence of the guiding devices 16, the outer panels 4 and 5 of the blank 2 (which constitute opposite ends of the blank 2) protruding from opposite sides of the wrapping drawer 7 (and therefore not they are bound to the wrapping drawer 7) they can be subjected to vibrations (oscillations) directed perpendicularly to the wrapping path P (i.e. vertically directed) when they leave the insertion station S1; such vibrations (oscillations) of the external panels 4 and 5 of the blank 2 which protrude from opposite sides of the wrapping drawer 7 can produce negative effects, as they undesirably modify the interaction of the external panels 4 and 5 with the devices 14 gummers and / or with the folding devices 15, consequently causing a worsening of the quality (precision) of the gumming and / or folding or, even, a flooding.

The power supply unit 8 described above has numerous advantages.

In the first place, the feeding unit 8 described above allows to improve the quality (precision) of the gumming and / or folding of the outer panels 4 and 5 of the blank 2 (which constitute opposite ends of the blank 2) which come out at overhang from opposite sides of the wrapping drawer 7. This result is obtained thanks to the presence of the guide devices 16 which prevent the external panels 4 and 5 of the blank 2 from protruding from opposite sides of the wrapping drawer 7 from vibrating (oscillating) at the outlet of the insertion station S1.

Furthermore, the power supply unit 8 described above is simple and inexpensive to manufacture, since the guiding devices 16 are made up of fixed profiles (i.e. without any moving part) of small size which must be fixed in the station. S1 insertion which is an area of the packing machine that is normally â € œfreeâ € and easy to access.

Claims (10)

R I V E N D I C A Z I O N I 1) Unit (8) for feeding a blank (2) to a drawer (7) of a conveyor (6); the feeding unit (8) comprises: an insertion station (S1) in which the drawer (7) of the conveyor (6) is stopped to receive the blank (2); and a transfer device (12) which transfers along a transfer direction (D) the blank (2) inside the drawer (7) of the conveyor (6) arranged in stop in the insertion station (S1) in such a way that at least one end (4; 5) of the blank (2) protrudes from the drawer (7); the feeding unit (8) is characterized by the fact that it comprises at least one guiding device (16) which is arranged in a fixed position immediately downstream of the insertion station (S1) along the path (P) for the advancement of the conveyor (6) and keeps the end (4; 5) of the blank (2) in a predetermined position which protrudes from the drawer (7) when the conveyor (6) moves the drawer (7) out of the station (S1 ) of insertion. 2) Feeding unit (8) according to claim 1, wherein the guiding device (16) comprises an upper guiding element (17) which is arranged above the path (P) of advancement of the conveyor (6) and prevents at the end (4; 5) of the blank (2) that protrudes from the drawer (7) to rise with respect to the feed path (P) of the conveyor (6). 3) Feeding unit (8) according to claim 1, wherein the guiding device (16) comprises a lower guiding element (18) which is arranged under the path (P) of advancement of the conveyor (6) and prevents at the end (4; 5) of the blank (2) that protrudes from the drawer (7) to lower with respect to the feed path (P) of the conveyor (6). 4) Feeding unit (8) according to claim 1, wherein the guide device (16) comprises an upper guide element (17) and a lower guide element (18) which are arranged above and below the path (P ) of advancement of the conveyor (6) and define a slot (19) through which the end (4; 5) of the blank (2) which protrudes from the drawer (7) passes. 5) Feeding unit (8) according to claim 4, in which the guide elements (17, 18) have a triangular shape towards the insertion station (S1) to give an inlet portion of the slot (19) a dimension progressively decreasing so as to have a self-centering function of the end (4; 5) of the blank (2) which protrudes from the drawer (7). 6) Feeding unit (8) according to claim 4 or 5, in which the upper and lower guide elements (17, 18) are U-shaped and define a first slot (19) arranged downstream of the station (S1) for insertion along the feed path (P) of the conveyor (6) and a second slot (19) arranged upstream of the insertion station (S1) along the feed path (P) of the conveyor (6). 7) Power supply unit (8) according to one of claims 1 to 6, wherein: in the insertion station (S1) two opposite ends (4; 5) of the blank (2) protrude from opposite sides of the drawer (7); and the feeding unit (8) comprises two guiding devices (16), which are arranged in a fixed position on opposite sides of the parked drawer (7) and keep the two corresponding ends (4; 5) in predetermined positions of the blank (2) that protrude from the drawer (7) when the conveyor (6) moves the drawer (7) out of the insertion station (S1). 8) Feeding unit (8) according to one of claims 1 to 7, wherein the transfer device (12) comprises at least one suction gripping head (13) which is alternately movable along the transfer direction (D) between the insertion station (S1) and a withdrawal station arranged above the insertion station (S1). 9) Feeding unit (8) according to claim 8 and comprising a hopper (11) which houses a stack of blanks (2), is arranged above the insertion station (S1), and has a lower extraction opening which defines the pick-up station. 10) Method of feeding a blank (2) to a drawer (7) of a conveyor (6); the feeding method includes the steps of: stop the drawer (7) in an insertion station (S1); and transfer, by means of a transfer device (12) and along a transfer direction (D), the blank (2) inside the drawer (7) of the conveyor (6) parked in the insertion station (S1) in such a way that at least one end (4; 5) of the blank (2) protrudes from the drawer (7); the feeding method is characterized by the fact of including the further step of keeping the end (4; 5) of the blank (2) in a predetermined position which protrudes from the drawer (7) when the conveyor (6 ) moves the drawer (7) out of the insertion station (S1) and by means of at least one guiding device (16) which is arranged in a fixed position immediately downstream of the insertion station (S1) along the feed path (P) of the conveyor (6).