The present invention relates to a method of transferring blanks.
More specifically, the present invention relates to a method of transferring blanks on an automatic packing machine for producing rigid packets of cigarettes, to which the following description refers purely by way of example.
To produce rigid packets of cigarettes, cardboard blanks must be fed to a pickup station of the packing machine so that each blank is withdrawn individually and folded about a group of cigarettes to form a packet of cigarettes.
The blanks are flat pieces of cardboard cut and notched beforehand to form fold lines, and are supplied in packages comprising a pallet on which the blanks are arranged for optimum transport and packing.
The blanks in each package are divided into side by side stacks to form layers, which in turn are stacked on the pallet and separated from one another by separators. The cigarette packing machine comprises a blank store for supplying the pickup station, where each blank is withdrawn individually by a gripping member and transferred to folding stations on the packing machine. In the store, the blanks are arranged in a seamless succession, and are packed and aligned with one another so as to be picked up by the gripping member in a given position and with a given orientation.
Given the increasingly fast output rate of automatic packing machines, all the blanks in the package must be transferred rapidly to the store to replace the empty pallet with a new package and, at the same time, arrange the blanks in the required orderly succession in the store.
Current transfer methods fail to provide for transferring and simultaneously arranging the blanks in the required orderly succession in the store, in such a manner as to meet the requirements of modern automatic packing machines.
U.S. Pat. No. 5,183,380 discloses a feeding apparatus for automatically transferring stacks of blanks from a pallet to a blank magazine of a high performance packaging machine. The feeding apparatus comprises an endless pocket conveyor between a feed station and the blank magazine; each pocket of the pocket conveyor receives a relevant blank stack in the feed station, transports the blank stack along a feeding path to the supply magazine, in which the stack is automatically pushed out of the conveyor pocket into the blank magazine. The feeding apparatus disclosed by U.S. Pat. No. 5,183,380 has a relatively high fast output rate; however, such feeding apparatus is cumbersome, complicated and expensive.
It is an object of the present invention to provide a method of transferring blanks, designed to eliminate the drawbacks of known methods.
According to the present invention, there is provided a method of transferring blanks, on a packing machine, from a platform supporting a number of blanks divided into stacks, to a store where the blanks are packed successively and seamlessly along a first supply path of a pickup station of the packing machine; the method being characterized by forming, at a loading station and by means of at least one gripping device, a group of blanks defined by at least two stacks superimposed and aligned in a container; feeding the container along a second path to an unloading station at the store; and transferring the group of blanks from the container to the store.
The above method provides for packing the stacks of blanks at the loading station and then transferring a group of packed blanks directly to the store.
Separating pickup of the blanks and transfer of the group provides for selecting, on the one hand, the most suitable gripping device for picking up the stacks on the platform, and, on the other, the most suitable container for forming the group and transferring the group to the store. Moreover, the container so accumulates the blanks as to enable supply of the platform.
The present invention also relates to a unit for transferring blanks.
According to the present invention, there is provided a transfer unit for transferring blanks on a packing machine comprising a blank store; the transfer unit comprising a platform for supporting a number of blanks divided into stacks, and at least one transfer device for transferring said stacks of blanks from the platform to the store, wherein the blanks are packed successively and seamlessly and aligned along a first supply path of a pickup station of the packing machine; and the transfer unit being characterized by comprising a container for housing a group of blanks defined by at least two aligned and superimposed stacks, and which is movable along a second path between a loading station at said gripping device and an unloading station at said store.
The present invention also relates to a packing machine store designed to cooperate with the transfer unit according to the present invention.
According to the present invention, there is provided a blank store forming part of a machine and cooperating with a transfer unit for transferring blanks; characterized by comprising a push device having a supporting wall perpendicular to a first path and movable along said first path to support the blanks in said store.
A number of non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, in which:
a, 7b, 7c show plan views, with parts in section and parts removed for clarity, of a
With reference to
That is, blanks 2 are arranged in side by side stacks 5 to form layers 6, which in turn are stacked on pallet 4 and separated from one another by separators 7. Stacks 5 rest on separators 7 or, in the case of the bottom layer 6, directly on pallet 4, and are unbound, i.e. have no bands or other wrappers, to simplify supply of blanks 2 to machine 1; and each blank 2 extends parallel to a horizontal plane perpendicular to the
Machine 1 comprises a frame 8 supporting a gripping member 9 for withdrawing one blank 2 at a time; a store 10 for storing blanks 2 and feeding blanks 2 along a path P1 to gripping member 9; and a transfer unit 11 for transferring stacks 5 of blanks from pallet 4 to store 10.
Transfer unit 11 comprises a container 12 movable along a given path P2 to transfer groups 13 of stacks 5; two gripping devices 14 and 15 for transferring stacks 5 of blanks; and a locating platform 16 for setting pallet 4 in a given position with respect to gripping device 14.
Gripping member 9 comprises a suction-type gripping head for withdrawing a blank 2 extending parallel to a vertical plane at a pickup station S1, and for feeding blank 2 to folding stations (not shown) of machine 1.
Store 10 comprises a conveyor 17 supporting a number of blanks 2 arranged in orderly fashion to assist withdrawal of each blank 2 by gripping member 9. In the orderly arrangement in store 10, blanks 2 are arranged successively, are packed and aligned with one another, extend parallel to said vertical plane, and rest on edge on conveyor 17, which extends a given length in a horizontal direction D1 from pickup station S1 to form a stock of blanks 2 for supply to pickup station S1.
Conveyor 17 comprises two spaced, parallel belts 18 looped about pulleys and which support blanks 2 resting on edge on the conveying branches of belts 18. Store 10 comprises an output gate 19; and a push device 20 for keeping blanks 2 in store 10 in the on-edge position. Gate 19 comprises a central opening (not shown), is located at pickup station S1, and provides for supporting the succession of blanks 2 and, at the same time, enabling gripping member 9 to penetrate output gate 19 to withdraw the blank 2 contacting gate 19.
As shown clearly in
Push device 20 comprises a sleeve 22, which is movable in direction D1 along a guide 21 parallel to conveyor 17, and is connected to a worm 23 activated by a motor 24. Push device 20 also comprises a supporting wall 25 perpendicular to direction D1 and connected to sleeve 22 by an articulated quadrilateral 26, which comprises a spring 27 extending between two opposite articulations of quadrilateral 26, and a sensor 28 for detecting deformation of spring 27. Sensor 28 is connected to a control unit 29 for operating motor 24, which sets sleeve 22, and therefore wall 25, to such a position as produce constant deformation of spring 27. That is, the position of wall 25 is determined by feedback control as a function of the expansion or contraction of spring 27 with respect to a set deformation value corresponding to a given pressure exerted by wall 25 on blanks 2 in store 10.
Wall 25 is connected to articulated quadrilateral 26 by means of a hinge 30, which has an axis parallel to direction D1 and is controlled by an actuator 31 to move wall 25 between a work position (shown by the continuous line in
With reference to
With reference to
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As shown in
With reference to
With reference to
Carriage 32 is connected to chain 51, as shown clearly in
As shown clearly in
With reference to
With reference to
Once blade 65 is inserted beneath a stack 5, jaw 66 is closed onto the stack 5 to withdraw it from package 3 and transfer it to gripping device 15. Gripping device 14 provides for adjusting the position of gripper 64 with respect to plane PA in direction D2, but has substantially no movement in direction D2.
With reference to
With reference to
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In actual use, store 10 and transfer unit 11 are controlled by control unit 29 shown schematically in
A package 3 of blanks is placed on platform 16 in the position defined by locators 61, and lifting device 62 positions package 3 so that the top separator 7 coincides with plane PA, which is determined by the position of sensor SL, and the top layer 6 of package 3 ideally rests on plane PA. Gripping device 14 takes one stack 5 at a time off the top layer 6 by means of gripper 64, and transfers each stack 5 to gripping device 15. When the whole layer 6 has been removed from package 3 by gripping device 14, separator 7 is removed and platform 16 is raised to move the next separator up to plane PA and sensor SL.
With reference to
The respective bottom portions of L-shaped lateral walls 71 provide for supporting stack 5, are coincident with plane PA, and are spaced apart; and, when transferring stack 5 from gripper 64 to transfer member 68, blade 65 is inserted between the bottom portions of lateral walls 71.
In the event stack 5 or even only one of blanks 2 in stack 5 is not aligned with gripper 64, lateral walls 71 flex by being mounted elastically. When gripper 64 releases stack 5, lateral walls 71 exert pressure on the misaligned stack 5 or blank 2 to position stack 5 correctly inside transfer member 68 and align any misaligned blanks 2 with the other blanks 2 in stack 5 by means of springs 76, which position walls 71 parallel and aligned with each other.
In the event walls 71 fail, under the action of springs 76, to position stack 5 or blanks 2 correctly with respect to transfer member 68, sensors 77 detect persistent deformation of springs 76 with respect to an optimum or threshold value, and control unit 29 sets transfer member 68 to reject position E to expel stack 5 by extending arms 70 to move end wall 69 forward.
Conversely, if the signal received by control unit 29 indicates no persistent deformation of springs 76 with respect to the optimum or threshold value, transfer member 68 is moved into the transfer position to transfer stack 5 to container 12. In other words, lateral walls 71 define a reference system for the blanks in each stack 5 transferred to transfer member 68, and at the same time provide for correcting the position of the blanks with respect to lateral walls 71 themselves.
Container 12 is moved into loading station S3 by means of carriage 32 activated by chain 51 and drive pulley 53. At loading station S3, bottom wall 38 of the carriage is perpendicular to direction D1; walls 39 and 40 are perpendicular to direction D2; and the empty container 12 is positioned so that wall 39 is practically coincident with plane PA. At this stage, and with reference to
Stacks 5 are placed one on top of the other inside container 12 until the top stack 5 nears wall 40. As container 12 is lowered one step further, wall 40 contacts stop member 79, which, in the meantime, has been set to the work position by actuator 80 and, at each step of carriage 32, moves wall 40 away from wall 39 and the superimposed stacks 5 to enable further stacks 5 to be placed one on top of the other to form a group 13 of blanks comprising a given N number of superimposed, aligned stacks 5.
In other words, at each step of carriage 32, carriage 32 positions container 12 at loading station S3 so that a supporting surface of container 12 is perpendicular to direction D2 and substantially aligned with plane PA. The supporting surface is defined by front wall 39 when container 12 is empty, and by the top blank 2 in container 12 when container 12 is partly filled.
The blanks 2 resting on the platform and on carriage 32 at loading station S3 extend perpendicularly to direction D2, while the blanks 2 housed in store 10 and container 12 at unloading station S2 extend perpendicularly to direction D1.
Once group 13 of blanks is completed, actuator 80 resets stop member 79 to the rest position, and wall 40 is positioned contacting the top blank 2 in group 13 by means of spring 50 (
Carriage 32 and container 12 are fed along path P2 and oriented so that bottom wall 38 of container 12 is parallel to direction D1, and blanks 2 are parallel to the blanks 2 in store 10, i.e. perpendicular to direction D1. Group 13 of blanks is transferred from container 12 to conveyor 17 along portion T.
Frame 41 of carriage 32 is so formed as to penetrate between belts 18 of conveyor 17 and superimpose paths P1 and P2. Carriage 32 is arrested upon container 12 contacting wall 25, which is moved by container 12 in direction D1. The movement of wall 25 is detected by sensor 28, which detects deformation of quadrilateral 26 and spring 27. As a result, control unit 29 successively stops chain 51, rotates wall 25 about hinge 30 into the rest position, and moves wall 25 in direction D1 into a position aligned with rear wall 40 of container 12. Wall 25 is then moved back into the work position shown by the continuous line in
As wall 25 is performing the above movements, wall 39 is lowered into the
A layer 6 of stacks is defined by an M number of side by side stacks, while each group is defined by an N number of superimposed stacks; and the relation between M and N may conveniently be selected so that M is a whole multiple of N, and so that a separator 7 can be removed and an empty pallet 4 replaced with a new package 3 as carriage 32 travels both ways between loading station S3 and unloading station S2.
Number | Date | Country | Kind |
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BO2000A0740 | Dec 2000 | IT | national |
Number | Name | Date | Kind |
---|---|---|---|
4907941 | Focke et al. | Mar 1990 | A |
4911608 | Krappitz et al. | Mar 1990 | A |
5074745 | Neri | Dec 1991 | A |
5183380 | Focke et al. | Feb 1993 | A |
5336040 | Focke et al. | Aug 1994 | A |
5340263 | Neri et al. | Aug 1994 | A |
5411362 | Neri et al. | May 1995 | A |
5417543 | Focke et al. | May 1995 | A |
5426921 | Beckmann | Jun 1995 | A |
5533854 | Focke et al. | Jul 1996 | A |
5582504 | Cestonaro | Dec 1996 | A |
5970834 | Garofano et al. | Oct 1999 | A |
6155775 | Depinet et al. | Dec 2000 | A |
6238173 | Corsini | May 2001 | B1 |
6546698 | Focke et al. | Apr 2003 | B1 |
Number | Date | Country | |
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20020090290 A1 | Jul 2002 | US |