EP2668104B1

EP2668104B1 - Command and control apparatus to control and command operating units of a packing machine and corresponding method

Info

Publication number: EP2668104B1
Application number: EP12710114.5A
Authority: EP
Inventors: Fiorenzo Draghetti
Original assignee: Gima TT SpA
Current assignee: IMA Industria Macchine Automatiche SpA
Priority date: 2011-01-26
Filing date: 2012-01-23
Publication date: 2017-04-05
Anticipated expiration: 2032-01-23
Also published as: CN103596845B; EP2668104A1; IN2013MN01546A; PL2668104T3; WO2012101493A1; RU2013138623A; CN103596845A; IT1403907B1; ITMI20110092A1; RU2587052C2

Description

FIELD OF THE INVENTION

The present invention concerns a command, control and safety apparatus and corresponding method, to control operating units of a packing machine, suitable to complete groups of smoking articles with the necessary components to make packets practically ready for sale.
The present invention also concerns a packing machine that comprises said command and control apparatus.

BACKGROUND OF THE INVENTION

From the Italian patent applications for industrial invention MO2010A000015 and MO2010A000016 a packing machine is known, comprising operating units suitable to transfer, position or fold groups of smoking articles and corresponding internal and external wrapping sheets and collars, or their parts, in order to pack them in packets which are practically ready for sale.
In particular the known packing machine comprises a central wrapping wheel moved by a single machine motor in order to wrap groups of smoking articles, wrapped by a corresponding first internal wrapping sheet, in a respective collar and in a respective second external wrapping sheet which is substantially flat.
This known machine also comprises at least the following operating units:

movement means to move organized groups of smoking articles already wrapped by the first internal wrapping sheet;
positioning means which position the collar radially and sequentially in peripheral housing drawers of the central wrapping wheel;
transfer means which transfer a group of smoking articles already wrapped in an internal wrapping sheet in a radial direction to the wrapping wheel, removing them from the movement means;
wheel type transfer means which deliver the second external wrapping sheet in a radial direction to holding means, which are present in cooperation with the respective peripheral drawers of the wrapping wheel,
wheel type final packaging and wrapping means which receive radially from the central wrapping wheel the material introduced therein on each occasion so as to form the packets.

In the known packing machine in question, the operating units are positioned on a single plane, vertical or slightly inclined with respect to the vertical and are driven by their own electric step motors. The machine differs from previous known packing machines, which lie on a horizontal plane or on several planes.
In one of the previous known machines, an encoder device is provided associated with the central wrapping wheel moved by the single motor machine. The encoder acts as a time base and therefore has the function of quantifying, determining and conditioning a desired angular movement of the central wrapping wheel and of the associated operating units. This desired angular movement is coordinated with a pre-constituted functioning and work program loaded into a memory of a processor and is intended to condition all the steps of assembling and packaging which lead to the final packet. The connected operating units which serve the central wrapping wheel, or which receive from it the material loaded on each occasion, are driven by programming the intervention of the corresponding movement unit on the basis of the cycle times of the functioning and work program.
An obvious disadvantage of this control configuration is that, in the event of breakage, malfunction, interruption, blockage, interference or other problem or anomaly which might affect one or another of the operating units, or parts of them, the result is that the remaining operating units continue to be subjected to the program, if the time base determined by the encoder does not intervene.
This can entail operations which cannot be carried out or which are missed out, or again situations of interference between devices or parts of these.
This situation is partly overcome traditionally with mechanical, electrical and/or electronic systems distributed in several parts of the packing machine, which perform the task of safety and limitations.
These conditions generate complexity in the machine, lack of safety and certainty along the work line, the need for a greater visual control, and an increase in maintenance requirements and reduction in productivity.
Moreover, from EP-A-0716016 a method and a machine are known for forming a rigid packet, for cigarettes or similar, provided with a cover and a collar, in which the use of a central rotating drum is provided.
From EP-A-0553636 a packing machine for box-like elements is known, having a winding wheel associated with an application wheel, which is made to rotate in synchrony and in an opposite direction to that of the winding wheel.
From EP-A-1396430 a machine and a method are known for the production of packets of cigarettes, which use a central rotary wheel.
From EP-A-0336012 a control device is known for a packaging machine provided with three motors: one associated with a conveyor belt, one to command a series of rollers and a third to command two sealing devices.
However none of the four above-mentioned patent documents describes a suitable control of the motors which optimizes the functions of the different operating units present in the machines.
One purpose of the present invention is to achieve a command, control and safety apparatus, and also to perfect the corresponding method, to manage the operating units in operating safety and in a reliable, precise and manageable way, in an automatic and auto-control manner so as to reduce the costs and times due to the stoppages of the machine, the waste of material and maintenance.
It is also a purpose to provide second intervention security to prevent blockages or interference.
The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.
In accordance with the above purpose, a command and control apparatus according to the present invention can be used to control the drive of at least two operating units, generically of the type described in the Italian patent applications MO2010A000015 and MO2010A000016 , of a packing machine, said operating units being suitable to complete smoking articles with accessories provided to obtain finished packets of smoking articles, in particular cigarettes, practically ready for sale.
According to the present invention, the machine, which extends for example on a single substantially vertical plane, comprises at least a central wrapping wheel suitable to complete one or more organized groups of smoking articles, possibly already wrapped in a first internal wrapping sheet, with at least a collar and at least a second external wrapping sheet, the wrapping wheel comprising peripheral housing drawers.
According to the present invention the command and control apparatus to control the machine comprises at least the following operating units:

a movement unit suitable to feed the smoking articles toward the wrapping wheel;
a positioning unit suitable to position sequentially a plurality of collars moving them in a radial direction with respect to the wrapping wheel, toward peripheral drawers of the wrapping wheel;
a first transfer unit suitable to transfer in a radial direction to the wrapping wheel the smoking articles already wrapped by an internal wrapping sheet, taking it from the movement unit;
a second transfer unit suitable to deliver an external wrapping sheet in a radial direction into the peripheral drawers of the wrapping wheel;
a wheel type final packaging and wrapping unit suitable to receive radially from the central wrapping wheel the material introduced therein on each occasion so as to form the packets;

According to a characteristic feature of the present invention, the command and control apparatus to control the machine also comprises a first step-wise servomotor associated with the wrapping wheel and at least two second step-wise servomotors each associated to one of at least two operating units, wherein each of the first and second step-wise servomotors is provided with a position transducer and is controlled by the central command and control unit of the programmable type, so that the first step-wise servomotor associated with the wrapping wheel is associated for the purposes of control and command in a bidirectional and independent manner with at least one of the two second step-wise servomotors of the operating units. Moreover, the central unit is configured to determine, for each pair that is created between the first step-wise servomotor and one of the second step-wise servomotors, a univocal and bidirectional dialog, which is assisted by the central unit, on the basis of the data and times memorized in the electronic memory and the information supplied by the position transducers of the step-wise servomotors involved, so that the information supplied by the transducers and associated to the dialog are compared by the central unit with the information contained in the electronic memory in order to verify they are in conformity with the corresponding work cycle to be carried out.
The control method according to the present invention to control the operations performed by two or more operating units of a packing machine for finished packets of smoking articles, provides to wrap at least partly, by means of a central wrapping wheel, at least an organized group of smoking articles, previously wrapped by a corresponding first internal wrapping sheet in a respective collar and in a respective second external wrapping sheet, and also provides at least one or more of the following operations performed by the operating units:

feeding the at least one organized group of smoking articles;
positioning the collar sequentially, moving it in a radial direction to the wrapping wheel by means of an operating positioning unit, in peripheral drawers of the wrapping wheel;
transferring, in a radial direction to the wrapping wheel, a group of smoking articles already wrapped by the internal wrapping sheet, taking it from a movement operating unit, by means of a first transfer operating unit;
delivering, in a radial direction to the wrapping wheel, the second external wrapping sheet by means of a second operating transfer unit;
packaging and wrapping, by means of wheel type final packaging and wrapping operating unit, the material received radially on each occasion from the central wrapping wheel so as to form the packets.

According to a characteristic feature, the control method of the present invention also provides both to use a first step-wise servomotor in order to drive the wrapping wheel and at least two second step-wise servomotors each associated with one of the operating units, wherein each of the step-wise servomotors is provided with a position transducer, and also to subordinate the functioning of the step-wise servomotors to a central command and control unit of the programmable type associated to an electronic memory containing a programmable data and times base which contains information relating at least to one or more work cycles to be carried out, the method also providing, for the purposes of control and command:

to associate, in a bidirectional and independent manner, the first step-wise servomotor of the wrapping wheel with at least one of the second step-wise servomotors of the operating units controlled by the central unit;
to determine, by means of the central unit, for each pair of step-wise servomotors, combined with each other, a univocal and bidirectional dialog, on the basis of the data and times memorized in the electronic memory and the information provided by the position transducers of the step-wise servomotors concerned, so that the information supplied by the transducers and associated to the dialog are compared by the central unit with the information contained in the electronic memory in order to verify they are in conformity with the corresponding cycle of work to be carried out;
to introduce possible corrections to the step-wise servomotors when the central unit finds any possible anomaly.

So, continuously and advantageously for every work cycle, a contemporary dialog is created, but only bidirectional between the servomotor which drives the central wrapping wheel and each of the servomotors which drive the operating units, in an independent manner even if everything is controlled and managed by the central unit.
This means that, for example, the servomotor which drives the central wrapping wheel dialogs bidirectionally with the servomotor which drives the movement means, at the same time and in an independent manner, it also dialogs with the servomotor which drives the positioning means, with the servomotor which drives transfer means, of the wheel or linear type, and with the servomotor which drives the wheel type final packaging and wrapping means and so on, and the results of the dialog and the corresponding information are received by the central control and command unit.
As a result the central unit continuously recognizes the exact reciprocal position of each of the operating units with respect to the central wrapping wheel and vice versa and, by derivation, the reciprocal position of all the operating units and of the wrapping wheel.
Moreover, the central unit, once it has recognized the precise position of all the operating units and of the wrapping wheel, verifies, on the basis of its own data and times base means, if this position is reciprocally correct and if it is in synchrony with data and times of the work program to be carried out, memorized in the data and times base means.
The command and control apparatus and method of the present invention, which impose advantageously for every work cycle a continuous and bidirectional dialog between the servomotor of the central wrapping wheel and on each occasion and in an independent way with each servomotor of the individual operating units, means that an angular positioning anomaly of the servomotor of one operating unit with respect to the angular positioning of the servomotor of the central wrapping wheel, and vice versa, conditions either one or the other of the servomotors and possibly even one or more of the other servomotors, slowing it/them down, accelerating or stopping it/them.
The invention also concerns economizing the cycle times, so that, for example, there is the problem of starting the functioning of one operating unit before the wrapping wheel is correctly positioned. According to the invention, the central unit constantly controls the reciprocal position of the operating unit and of the wrapping wheel, conditioning the step-wise servomotor of the operating unit so that at the desired moment the two units concerned are in phase.
The invention also concerns the preparation of safety systems which control the absorption of electric current of the individual servomotors and, through the central unit provided with electronic comparison and control means, compare it with electric current values ranges, which define safety thresholds, associated, by means of data and times base means, to the specific operating sub-step in progress in each individual operating unit and in the wrapping wheel. In this way, for example, if the sub-step provides a stoppage while an absorption of electric current lower than the minimum threshold is in progress, or is still in progress, the control system identifies this as an anomaly. In the same way, if in determinate operating sub-steps, an absorption of electric current beyond the maximum threshold is detected, this may indicate an interference or mechanical blockage, and in this case too the control identifies this as an anomaly and acts accordingly. In this way we obtain an accurate and direct control of every single working step associated with and involving the central wrapping wheel and in cascade all the connected steps, both upstream and downstream, as they are performed in and in relation to the packing machine.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein:

- Fig. 1: is a front schematic view of a command and control apparatus according to the present invention associated to a packing machine;
- Fig. 2: is a schematic view from above, with some details removed to better highlight others, of the packing machine in fig. 1;
- Fig. 3: schematically shows the architecture of the apparatus and control method of the present invention;
- Figs. 4 and 5: schematically show two cases of absolute interference between operating units;
- Fig. 6: shows a case of relative interference;
- Fig. 7: shows a block diagram of the safety systems actuated by the control of the present invention;
- Figs. 8 and 9: schematically show two cases of intervention of the control according to the present invention;
- Fig. 10: shows a block diagram of the alternate functioning logic of the present invention.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one form of embodiment can conveniently be incorporated into other forms of embodiment without further clarifications.

DETAILED DESCRIPTION OF SOME PREFERENTIAL FORMS OF EMBODIMENT

Fig.1 shows a command and control apparatus 50 according to the present invention which can be used in a packing machine 1 of the type in question, to pack smoking articles, in particular cigarettes, in packets 3 ready for sale.
The packets 3, of the rigid type, once made comprise:

a first internal wrapping sheet 4, for example a sheet of foil or metallized paper, housing and wrapping a group, or composition of cigarettes;
a collar 6, made of cardboard for example, possibly coupled with a metal sheet, at least partly wrapping the first internal wrapping sheet 4, for example to form an internal packaging of the final packet 3 and disposed, among other things, to stiffen the packet 3 and keep a lid of the latter closed;
a second external wrapping sheet 8 or punched piece, intended to form the external walls of the packets 3 and therefore to wrap the collar 6 and the group of cigarettes wrapped in the first internal wrapping sheet 4.

The packing machine 1 extends along a single substantially vertical plane and comprises a formation conveyor, not shown as it is of a known type, to at least partly wrap the groups of cigarettes in corresponding first internal wrapping sheets 4.
The packing machine 1 also includes movement means 9 (fig. 2) driven by an electric motor 71, advantageously a step motor of the brushless type, in order to move the groups of wrapped cigarettes, at least partly, in their corresponding internal wrapping sheets 4, along a substantially horizontal direction of movement M. In this case, the movement means 9 comprise an endless belt 10 closed in a ring around two pulleys, not shown, rotating around respective horizontal axes, and advancing with varied motion along the direction of movement M. In the solution shown, the movement means 9 also comprise a plurality of abutment elements 11, attached to the endless belt 10 and which extend transversely with respect to the direction of movement M, disposed to abut on a smaller side of the group of cigarettes wrapped in the corresponding internal wrapping sheets 4 so as to move the latter along the direction of movement M.
The machine 1 also comprises a central wrapping wheel 13, to complete at least one organized group of smoking articles, previously wrapped by a corresponding first internal wrapping sheet 4, with at least a collar 6 and at least a respective second external wrapping sheet 8 and comprising peripheral drawers 14 with housing compartments.
The machine 1 also comprises, in this case, at least the following operating units, disposed around the central wrapping wheel 13 in a substantially circular configuration:

positioning means 25 which positions the collar 6 sequentially, moving it in a radial direction with respect to the wrapping wheel 13, in the peripheral drawers 14;
transfer means 22 which transfer in a radial direction to the wrapping wheel 13 a group of smoking articles already wrapped by the first internal wrapping sheet 4, taking it from the movement means 9;
transfer means, in this case a transfer wheel 27, although they could be linear, like conveyor belts, which deliver the second external wrapping sheet 8 in a radial direction into the peripheral drawers 14 of the wrapping wheel 13;
wheel type final packaging and wrapping means 34 which receive radially from the central wrapping wheel 13 the material introduced therein on each occasion so as to form the packets 3.

In particular the wrapping wheel 13 comprises a disc-shaped body 15, supporting a plurality of the peripheral drawers 14, positioned radially.
The wrapping wheel 13 is driven in rotation, by steps, by an electric step-wise servomotor 71, advantageously of the brushless type (shown only schematically in fig. 1), around a axis of rotation R substantially parallel to the direction of movement along a circular wrapping path P shown with a line of dots and dashes in fig. 1.
In variant solutions the transfer means 22 comprise a first thruster 24 and a second thruster 24 cooperating with each other to hold and insert in succession into the peripheral drawers 14 one of the groups of cigarettes wrapped by the first internal wrapping sheet 4.
The first thruster 23 and the second thruster 24, mutually facing each other, are slidingly supported respectively by the movement means 9 described above, and by the wrapping wheel 13, and are positioned in correspondence to a first loading station PSC of the wrapping wheel 13.
The first thruster 23 and the second thruster 24 are driven, by steps, by an electric step-wise servomotor 71, advantageously of the brushless type (shown only schematically in fig.1).
In accordance with some forms of embodiment of the present invention, the positioning means 25, disposed in correspondence to a second loading station SSC of the wrapping wheel 13, are driven with an alternate motion by a step-wise servomotor not shown in fig. 1, and move the collars 6 along a direction D, substantially rectilinear and radial with respect to the wrapping path P.
In particular, the second loading station SSC is positioned upstream of the first loading station PSC with respect to the wrapping path P.
In some variants, the positioning means 25 include a punch element 41 conformed so as to be able to be inserted, at least partly, in one compartment of the peripheral drawers 14, and provided with one or more suckers, not shown, in order to hold and move the collars 6, one at a time.
According to variants of the invention, the packing machine 1 also comprises other transport means 26 (fig.1) in order to transfer each second wrapping sheet 8 in succession onto a corresponding peripheral drawer 14 above a respective group of cigarettes packed in a first internal wrapping sheet 4 and wrapped, at least partly, by a collar 6.
In particular, the other transfer means 26 are positioned in correspondence to a third loading station TSC of eh wrapping wheel 13, the third loading station TSC being positioned downstream of the first loading station PSC with respect to the wrapping path P.
The other transfer means 26 comprise the transfer wheel 27, which is provided radially with a plurality of holding elements 27 in order to each hold, a respective second wrapping sheet 8.
In particular, the transfer wheel 27 is able to move the second wrapping sheets 8, by means of the holding elements 28, along a movement path PM, shown with a line of dots and dashes in fig. 1, substantially circular and substantially coplanar to the wrapping path P.
Moreover, the transfer wheel 27 is driven in rotation, by steps, by an electric step-wise servomotor 71, advantageously of the brushless type (shown only schematically in fig.1), around an axis W substantially parallel to the axis of rotation R, with direction of rotation opposite to the direction of rotation of the wrapping wheel 13.
The other transfer means 26 also comprise a first transfer arm 29 in order to transfer, in succession, the second wrapping sheets 8 between a store 30 of second wrapping sheets 8 and one of the holding elements 28.
In particular the first transfer arm 29 is driven with alternate motion and rotates around a first axis of rotation A1 substantially parallel to the axis W.
The other transfer means 26 are also provided with a second transfer arm 31 in order to transfer in succession the second wrapping sheets 8 between one of the holding elements 28 and a corresponding peripheral drawer 14 above a group of cigarettes 5 packed in the internal wrapping sheet 4 and wrapped, at least partly, by a collar 6.
In particular the second transfer arm 31 is driven with alternate motion and rotates around a second axis of rotation A2 substantially parallel to the axis W.
More precisely, the second transfer arm 31 moves the second wrapping sheets 8 along a transfer trajectory TT, shown with a line of dots and dashes in fig. 1, substantially rectilinear and radial with respect to the wrapping path P.
Moreover, the second transfer arm 31 comprises an end portion 32, having a profile like a "C", in order to fold toward the inside peripheral zones of each second wrapping sheet 8 and make them abut against respective lateral walls of a corresponding peripheral drawer 14.
The wheel type final packaging and wrapping means comprise, in this case, another wrapping wheel 34 (fig. 1), of the known type and therefore not described in detail, in order to complete the folding of the second wrapping sheets 8 around the organized groups of cigarettes, previously wrapped in the internal wrapping sheets 4 and collars 6, so as to form packets 3.
In particular, the other wrapping wheel 34 is able to move the organized groups of cigarettes, packaged in the internal wrapping sheets 4 and wrapped in the collars 6 and at least partly in the second wrapping sheets 8, along another wrapping path UP, substantially circular and shown with a line of dots and dashes in fig. 1, along which, around each group of cigarettes previously wrapped in a corresponding first internal wrapping sheet 4 and a collar 6, a corresponding second wrapping sheet 8 is folded to form the packet 3.
In particular, the other wrapping wheel 34 is driven in rotation, by steps, by an electric step-wise servomotor 71, advantageously of the brushless type (shown only schematically in fig. 1), around another axis of rotation UR substantially parallel to the axis of rotation R, the direction of rotation of the other wrapping wheel 34 being opposite the direction of rotation of the wrapping wheel 13.
The other wrapping wheel 34 is substantially coplanar to the wrapping wheel 13 and to the transfer wheel 27.
The other wrapping wheel 34 comprises another disc-shaped body 35, supporting a plurality of other peripheral drawers 36 positioned radially to receive the groups of cigarettes 5 packaged in the internal wrapping sheets 4 and wrapped by the collars 6 and by the second wrapping sheets 8.
In variant solutions, the packing machine 1 also comprises other transfer means 37 (fig. 1) to transfer, in succession, along another transfer direction UT, radial with respect to the wrapping path P, from each of the peripheral drawers 14 to each of the other peripheral drawers 36, a corresponding group of cigarettes packaged in a first internal wrapping sheet 4 and wrapped, at least partly, by a collar 6 and by a second external wrapping sheet 8.
In particular, the other transfer direction UT is transverse to the direction of movement M and is substantially coplanar to the transfer direction T.
The other transfer means 37 comprise another first thruster 38 and another second thruster 39 cooperating with each other to hold and to insert in succession in each other peripheral drawer 36 a corresponding group of cigarettes 5 packaged in an internal wrapping sheet 4 and wrapped, at least partly, by a collar 6 and a second wrapping sheet 8.
In particular the other first thruster 38 and the other second thruster 39 are driven with alternate motion by a step-wise servomotor, not shown in fig. 1, and in plane have a shape such that they can be inserted into, without knocking against the walls of, passages, not shown, made inside the peripheral drawers 14 and the other peripheral drawers 36.
The groups of cigarettes wrapped by the internal wrapping sheet 4 are inserted into a corresponding other peripheral drawer 36 so that the corresponding second wrapping sheet 8 faces with one face a corresponding other peripheral drawer 36, another face of the second wrapping sheet 8, opposite the above face, facing another and bigger opposite side, of the groups of cigarettes wrapped in the corresponding internal wrapping sheets 4.
The other first thruster 38 and the other second thruster 39, mutually facing each other, are slidingly supported respectively by the wrapping wheel 13 and by the other wrapping wheel 34 and are positioned in correspondence to an unloading station SS of the wrapping wheel 13.
The unloading station SS is positioned downstream of the third loading station TSC along the wrapping path P.
In variant embodiments, the packing machine 1 also comprises an unloading conveyor 40 (fig. 1), of a known type and therefore not described in detail, so as to remove the packets 3 formed by the other wrapping wheel 34 and to unload them radially from the packing machine 1.
When working, the positioning means 25 radially position a respective collar 6 in succession, into each empty peripheral drawer 14, in correspondence to the second loading station SSC.
Subsequently, the collars 6 are moved along the wrapping path P and are stopped in succession in correspondence to the first loading station PSC.
In the first loading station PSC the transfer means 22 radially transfer, in succession, each group of cigarettes previously at least partly packaged in a corresponding internal wrapping sheet 4, by movement means 9 to the wrapping wheel 13 in a respective compartment holding a collar 6. In this way, each group of cigarettes packaged in a corresponding internal wrapping sheet 4 is wrapped on three sides by a respective collar 6.
Subsequently, the groups of cigarettes packaged in the internal wrapping sheets 4 and wrapped, at least partly, by the collars 6, are moved along the wrapping path P and are stopped in succession in correspondence to the third loading station TSC. In the third loading station TSC the other transfer means 26 transfer radially, in succession, each second external wrapping sheet 8 on a corresponding peripheral drawer 14 above a corresponding group of cigarettes 5 packaged in an internal wrapping sheet 4 and wrapped, at least partly, by a respective collar 6.
In correspondence with the third loading station TSC, the holding means of the peripheral drawer 14, positioned in correspondence with the lateral walls 18, are driven so as to hold the second wrapping sheet 8 anchored to the peripheral drawer 14.
Subsequently, the groups of cigarettes packaged in the internal wrapping sheets 4 and wrapped, at least partly, by the collars 6 and by the second wrapping sheets, are moved along the wrapping path P and are stopped in succession in correspondence to the unloading station SS.
In the unloading station SS the holding means of the peripheral drawer 14 are released, so as to allow the other transfer means 37 to transfer radially, in succession, from each of the peripheral drawers 14 to each of the other peripheral drawers 36 a corresponding group of cigarettes packaged in a first internal wrapping sheet 4 and at least partly wrapped by a collar 6 and a second external wrapping sheet 8.
Subsequently again, each group of cigarettes packaged in an internal wrapping sheet 4 and at least partly wrapped by a collar 6 and a second wrapping sheet 8, is moved by the other wrapping wheel 34 along the other wrapping path UP along which, around each of the groups of cigarettes a corresponding second wrapping sheet 8 is folded to form the packet 3.
Subsequently, the packets 3 thus formed are transferred radially to the discharge conveyor 40 and discharged from the packing machine 1.
According to the present invention, the command and control apparatus 50 comprises the step-wise servomotors 71 each of which is provided with a corresponding position transducer, such as an encoder or other mean functioning as an encoder, in this case electric step motors of the brushless type, and are controlled by a central command and control unit 100 of the programmable type (shown only schematically in fig. 1). As we said, each of the servomotors 71 is directly and univocally associated with a corresponding operating unit including at least the movement means 9, the wrapping wheel 13, the positioning means 25, the transfer means, wheel type or linear, such as conveyor belts 27, and the wheel type final packaging and wrapping means 34.
It should be noted that the present invention, exploiting the use of servomotors 71 on the various operating units as above and the presence of a position transducer inside them, directly connected to the shaft and hence to the load, has the effect of preventing play and friction, with the advantage of lower energy consumption and of being able to manage the safety, friction and interferences on an electronic level, in an efficient and reliable manner.
In some forms of embodiment, the servomotors 71 comprise or are associated with current sensor means suitable to detect a signal indicative of the electric current absorbed by the servomotors 71, which is transmitted to the central command and control unit 100 to control the functioning thereof, as described in more detail hereafter.
It is understood that the various operating units can be provided, in advantageous solutions of the present invention, with one or more presence sensor means, not shown, for example optical sensors, such as photocells, mechanical sensors such as sensitive edges, pressure sensors or other, suitable to detect the presence or absence of material, that is, groups of cigarettes, wrapping sheets 4, 8 and collars 6, on the various operating units and/or the presence/absence of a specific operating part of a determinate operating unit, and to transmit the corresponding signal to the central command and control unit 100.
In some forms of embodiment, the presence sensor means may be disposed both on one, the other or on several of the operating units that serve upstream the central wrapping wheel 13, for example the movement means 9, the positioning means 25, the transfer means 27, both on the central wrapping wheel 13 itself and also on the operating units downstream of it, in this case at least the wheel type final packaging and wrapping means 34.
The central command and control unit 100 facilitates the control and automation of the machine 1 and may comprise a central processing unit (CPU) 102, which can perform the function of electronic comparison and control means, a memory (not shown) and auxiliary circuits (or I/O) (not shown).
In particular, the central command and control unit 100 comprises or is associated with an electronic data and times base 101 of the programmable type.
The CPU 102 of the central command and control unit 100 may be any type of processor for computers that are used in industrial regulations to control different processes and hardware devices (such as conveyors, detectors, motors etc.) and to monitor the system and operations performed. The memory is connected to the CPU and may be one or more of those available, like a random access memory (RAM), a read-only memory (ROM), floppy disc, hard disc or any other form of digital local or remote storage. The software instructions and the data may be encoded and memorized in the memory to command the CPU 102. The auxiliary circuits too are connected to the CPU 102 to help the processor in a conventional manner. The auxiliary circuits may include cache circuits, feed circuits, clock circuits, input/output circuits, sub-systems and suchlike.
A program (or computer instructions) legible by the central command and control unit 100 determines which functions can be carried out on each occasion in the operating units as above. Preferably, the program is a software legible by the central command and control unit 100, which comprises a code to generate and memorize at least information of the angular position of the various operating units, which correspond to information on the position of the groups 5 of smoking articles 2 wrapped in the first internal wrapping sheet 4, the collar 6 and the second external wrapping sheet 8, the sequence of movement of the various components controlled, and any other corresponding combination.
Consequently, the programmable central command and control unit 100 is configured to manage and command one or more of the following electric motors 71 of the first thruster 23 and the second thruster 24 of the transfer means 22, of the other first thruster 38 and the other second thruster 39 of the other transfer means 37, of the positioning means 25, of the first transfer arm 29, the second transfer arm 31 of the other transfer means 26, of the movement means 9, the central wrapping wheel 13, the transfer wheel 27 of the other transfer means 26 and the other wrapping wheel 34.
Thanks to this, a control architecture of the command and control apparatus 50 according to the present invention is created, which is based on the thorough identification of pairs of operating units to be managed by the machine 1, of which a first component is generally the central wrapping wheel 13 and the second component is a remaining operating unit. These pairs of operating units are configured to communicate with each other at least the information detected by the position transducers of the associated servomotors 71 and to transmit the corresponding information to the central command and control unit 100.
According to the present invention, the control architecture of the command and control apparatus 50 is thus suitable to effect a univocal and bidirectional dialog between the servomotor 71 that controls the central wrapping wheel 13 and each of the servomotors 71 that control at least the movement means 9, the transfer means 22, the positioning means 25, the transfer wheel 27 and the other wrapping wheel 34 and possibly the other transfer means 37.
The bidirectional dialog takes place continuously and simultaneously between the components cited above and is assisted by the central command and control unit 100, involving the position transducer of the servomotors 71 involved on each occasion.
In this way a dialog is created, continuously and simultaneously, but only bidirectional, between the servomotor 71 that drives the central wrapping wheel 13 and each of the servomotors that drive the operating units. The result of the dialog is transmitted to the central command and control unit 100 which compares it with the information memorized in its data and time base means 101, to verify both the reciprocal coordination of the two units involved and also the coordination of the two units with the remaining units, the coordination of the two units and, by derivation, of the two remaining units with the work program set.
A possible malfunction or anomaly is identified according to the signals transmitted, for each pair of operating units, by the corresponding servomotor 71, and by a comparison with the data and time base means 101 by the central command and control unit 100 which suitably commands the servomotor 71 for the correct functioning of the packing machine 1, providing braking, acceleration or stoppages in the movement of the various units.
In particular, the present invention provides to obtain a command and control apparatus 50 with pairs of the various operating units as above, in which the pairs each refer to the central command and control unit 100, transmitting the data and information of the corresponding position transducers present in the servomotors 71.
Fig. 3 shows a diagram of the control architecture of the command and control apparatus 50 according to the present invention in which, for a selected pair of operating units indicated for convenience by A and B, the biunivocal relation is identified between a first component A, which is generally the central wrapping wheel 13 and a second component B, and how this relation is managed by the central command and control unit 100, by means of the corresponding data and times base means 101, also in ratio with the analogous relations simultaneously occurring between the first component A and the other remaining operating units, indicated by B 1, B2, B3, B4.
The control according to the present invention provides to effect, for a selected pair of operating units A and B, A and B1, A and B2, A and B2, A and B3, A and B4, a reciprocal control of the angular position of the corresponding servomotors 71 by means of the associated position transducers and, at the same time, an analogous control between the remaining pairs of operating units, to send the information relating to the controls carried out by the central unit 100 and to verify the correctness of the angular positions detected with respect to the provisions in the data and times base means 101, possibly as a consequence accelerating, braking or stopping the movement of one or more of the operating units, according to the anomaly identified.
In particular, with the present invention it is possible to implement at least two types of controls for each pair A and B, A and B1, A and B2, A and B2, A and B3, A and B4, of operating units as defined above, that is:

a) control of interference between the various axes (absolute and relative);
b) control of torque overload (evolved electronic friction).

Control a) works on pairs of movements associated with the two operating units of the pair of units to be controlled.
Depending on the actual initial dynamics and on pre-set reference or threshold dynamic parameters, the central command and control unit 100 calculates the guaranteed braking space and time of the movement that is entering into interference.
Subsequently, the central command and control unit 100 compares the values calculated with the position where the rotation shaft of the other operating unit involved will be after the braking time.
If the positions are interfering, the central command and control unit 100 emits a controlled stoppage signal, stopping the movements before the interference between the units. When the stoppage time has passed the torque will be removed from the servomotors concerned in order to restart operations.
The control inverts the roles of the two movements depending on the position inside the work cycle memorized in the data and times base means 101, according to which drive shaft of the two operating units could enter into interference. In particular, hereafter the present invention is illustrated with reference to two operating units as described above, indicated as A and B for convenience, the following description being extendible to any other pair of two operating units A and B1, A and B2, A and B3, A and B4 of the machine 1 described above, with the provision that the first component A is generally the central wrapping wheel 13.
Fig. 4 illustrates the interference between two units A and B, in particular the instant when unit A starts moving and unit B is exiting from interference, indicating with W and V the respective representative speed vectors, angular and linear.
The central command and control unit 100 controls that in the minimum time in which it will be possible to stop A outside the interference with B (TstopA), B has already left the zone of interference. Time TstopA is a function of the actual dynamics of unit A, and also of the pre-set threshold dynamic parameters.
This control is based on the calculation of the stop coordinates or position of unit A (YstopA), function of TstopA, and the coordinates or actual position of unit B, function of the actual dynamics of unit B and Tstop A.
Fig. 5 shows the interference between unit B and unit A, in particular the instant when unit B starts moving and unit A is exiting from interference.
The central command and control unit 100 controls that in the minimum time in which it will be possible to stop B outside the interference with A (TstopB), A has already left the zone of interference. Time TstopB is a function of the actual dynamics of unit B, and also of the pre-set threshold dynamic parameters.
This control is based on the calculation of the stop coordinates or position of unit B (YstopB), function of TstopB, and the coordinates or actual position of unit A, function of the actual dynamics of unit A and Tstop B.
In both cases the control is carried out with every cycle so as to be rapid in the event of instantaneous changes in the dynamics.
In general, the interferences can be absolute (as in figs. 4 or 5) in the case of movements whose trajectories form an angle other than zero, or relative (fig. 7) if the trajectories are on the same directrix. The management is the same with the difference that in the second case the central command and control unit 100 operates on a difference in position between the movements and not on a fixed amount of non-interference.
Control mode b) of the torque overload as above refers in particular to a torque reference curve provided at movement (C=I*α) on which a tolerance window or range is opened. If the torque does not come within this window, the central command and control unit 100 will emit the same immediate stoppage signal cited above.
In particular, having identified a range of values of current absorbed by the servomotors 71 and detected by the current sensor means, it is verified whether, in position YactualA or YactualB, the instantaneous current value absorbed by the servomotors 71 is outside the reference range. If positive, the command and control apparatus 50 stops the units A and B concerned. To this purpose, the electric current sensor means of the servomotors 71 communicate the respective signals to the central command and control unit 100 with every control cycle, exploiting the control architecture described with regard to fig. 3. This control gives protection both against torque overloads and also against mechanical breakages (lower torque required to move the user machine).
Fig. 7 shows a block diagram of the safety measures enacted by the command and control apparatus 50 according to the present invention, as described briefly above in relation to a pair of units A and B, and can be extended to any pair whatsoever of units A and B1, A and B2, A and B3, A and B4 of the machine 1 shown above.
The main conditions why the command and control apparatus 50 is suitable to stop the movements before a mechanical interference included in the following events signaled in the block diagram in fig. 7 as serious errors: failure in activation, break-down in activation, breakage of the cable on the bus propagating the positions, broken encoder on the motor, broken motor, broken CPU.
The control logic of the command and control apparatus 50 according to the present invention provides that the automation, being developed modularly between pairs of operating units A and B 1, A and B2, A and B3, A and B4 of the machine 1 shown above and completely motorized, makes it possible to stop, for one or more cycles, the operating units or pairs of units that do not have any anomalies, so that it is possible to proceed with the units or pairs of units that, on the contrary, have shown anomalies in the corresponding cycle. This allows to keep the machine productive and prevents the discard of any product or material. The command and control apparatus 50 in general provides to exploit the positioning of the presence sensor means described above, and in the event of an absence of material in a given controlled position of a determinate operating unit, or in the event of an absence, or unexpected presence, of a specific operating part of one of the operating units, it can actuate:

an overall stoppage of the machine 1, or
a stoppage of the operating unit controlled and the units upstream thereof, while the operating units downstream and the wrapping wheel are made to operate until the subsequent units downstream of the unit controlled are emptied.

This also applies to the movement means 9 which deliver to the central wrapping wheel 13 the organized groups of smoking articles already wrapped in the first internal wrapping sheet 4. In this specific case, the presence sensor means may be disposed on the movement means 9, or in correspondence with the entrance to the wrapping wheel 13, or again in each of the peripheral drawers 14 of the central wrapping wheel 13 or in all these positions, to alternatively verify the presence of material and/or the specific part of the operating unit.
With reference to figs. 8 and 9, some examples will now be shown of cases where the actuation of the control according to the present invention intervenes, assisted by the use of the presence sensor means as above, to verify the presence of the necessary material and the accessories on the operating units.
Fig. 8 in particular shows the case where no material is picked up at the step signaled by arrow VII. In this situation, at the appropriate time, the motorization indicated by III will proceed to recoup the missing position, while the motorizations I, II, IV, V, VI will stop in the case of continuous functioning or will remain stationary in the case of alternate functioning for the duration of one cycle. This allows to leave the automation functioning, not discarding any product or material. This logic can be extended to every unit of the automation of the machine 1, achieving very high efficiency compared with a mechanical automation.
Furthermore, the control logic of the command and control apparatus 50 according to the present invention provides that the automation makes it possible to immediately stop the individual unit in the event of flooding, allowing to stop the previous units in phase and to empty the subsequent units, thus reducing to a minimum the discards at the subsequent re-start after the flooding has been remedied (in most cases eliminating the discard completely).
Fig. 9 in particular shows the case of flooding on working the product in box XII. The command and control apparatus 50 will automatically stop the unit indicated by IX with an immediate stoppage, group VIII and X in phase and the subsequent units not displayed will be able to empty.
Upon the subsequent re-start after the flooding has been remedied and the products damaged inside the box have been removed, units VIII and X will remain stationary for a step, while unit IX will perform one step, taking a product XI to be worked and not leaving any empty spaces on unit VIII and thus it is possible to re-start without having to discard any product or material afterward.
The command and control apparatus 50 is therefore able to implement an "intelligent" sequential logic that guarantees that an automation speed set by the operator is respected, precisely and not constrained to the sequential consents that are expected, and in any case guaranteeing the safety of the mechanical parts in the event of error of any motorized movement.
Fig. 10 shows a block diagram of the alternate functioning logic which allows to easily put into practice what is described above, and provides a verification step to verify, by means of the corresponding presence sensor means, if the material is present on the unit to be controlled and, in cascade, a step to verify the presence of the materials on the other units, by means of the respective presence sensor means. If both verifications are positive, the work cycle is carried out, otherwise the method provides to repeat the control from the beginning.

Claims

Control method to control the operations performed by two or more operating units (22, 25, 26, 27, 34, 37) of a packing machine (1) for finished packets of smoking articles, extending along a single substantially vertical plane, which provides to wrap at least partly, by means of a central wrapping wheel (13), at least one organized group of smoking articles, previously wrapped by a corresponding first internal wrapping sheet (4) in a respective collar (6) and in a respective second external wrapping sheet (8);
and which provides at least one or more of the following operations performed by said operating units (22, 25, 26, 27, 34, 37):
- feeding said at least one organized group of smoking articles along a substantially horizontal direction of movement (M) parallel to an axis of rotation (R) of said wrapping wheel (13);

- positioning the collar (6), moving it in a radial direction to said wrapping wheel (13) by means of a positioning operating unit (25), sequentially in peripheral drawers (14) of said wrapping wheel (13);

- transferring, in a radial direction to said wrapping wheel (13), a group of smoking articles already wrapped by the internal wrapping sheet (4), taking it from a movement unit (9), by means of a first transfer unit (22);

- delivering in a radial direction to said wrapping wheel (13) the second external wrapping sheet (8) by means of a second transfer unit (27);

- packaging and wrapping, by means of a wheel type final packaging and wrapping unit (34), the material received radially on each occasion from said central wrapping wheel (13) so as to form the packets (3);
characterized in that it also provides to use both a first step-wise servomotor (71 A) in order to drive said wrapping wheel (13) and at least two second step-wise servomotors (71B) each associated with one of said operating units (22, 25, 26, 27, 34, 37), wherein each of said step-wise servomotors (71A, 71B) is provided with a position transducer, and also to subordinate the functioning of said step-wise servomotors (71 A, 71B) to a central command and control unit (100) of the programmable type associated to an electronic memory containing a programmable data and times base (101) which contains information relating to one or more work cycles to be carried out, said method also providing, for the purposes of control and command:
- to combine, in a bidirectional and independent manner, said first step-wise servomotor (71 A) of said wrapping wheel (13) with at least one of said second step-wise servomotors (71B) of said operating units (22, 25, 26, 27, 34, 37) controlled by said central unit (100);

- to determine, by means of said central unit (100), for each pair (A-B1; A-B2; A-B3; A-B4; A-Bn) of step-wise servomotors (71 A, 71B), combined with each other, a univocal and bidirectional dialog, on the basis of the data and times memorized in said electronic memory containing the programmable data and times base (101) and the information provided by the position transducers of the step-wise servomotors (71 A, 71B) concerned, so that the information supplied by said transducers and associated to said dialog are compared by the said central unit (100) with the information contained in said electronic memory containing the programmable data and times base (101) in order to verify their conformity with the corresponding work cycle to be carried out;

- to introduce possible corrections to said step-wise servomotors (71 A, 71B) when said central unit (100) finds any possible anomaly;
wherein said method provides to effect, by means of said central unit (100) and presence sensor means, for each of said pairs (A-B1; A-B2; A-B3; A-B4, A-Bn) of step-wise servomotors, a first verification of the presence of a determinate material selected from among one or the other of said organized group of smoking articles, first (4) and second (8) wrapping sheet and collar (6) on a first component (A) of the pair of step-wise servomotors and/or the presence or absence of a specific operating part of one of said operating units (22, 25, 26, 27, 34, 37) and/or said central wrapping wheel (13) and, if positive, a second verification of the presence of a coordinated material selected from one or the other of said organized group of smoking articles, first (4) and second (8) wrapping sheet and collar (6) on a second step-wise servomotor (B1, B2, B3, B4, Bn) of the pair and/or the presence or absence of a specific operating part of one of said operating units (22, 25, 26, 27, 34, 37) and/or said central wrapping wheel (13) and in a further positive case to start the work cycle, whereas in a negative case for the first or the second verification to repeat the control cycle from the start.
Method as in claim 1, characterized in that it provides:
- to effect, for a selected pair (A-B1; A-B2; A-B3; A-B4; A-Bn) of the step-wise servomotors (71 A, 71B) a reciprocal control of the angular position of the corresponding step-wise servomotors (71 A, 71B) by means of the associated position transducers;

- to simultaneously effect a similar control of the remaining pairs (A-B1; A-B2; A-B3; A-B4; A-Bn) of the step-wise servomotors (71 A, 71B);

- to transmit the information relating to the controls carried out to said central unit (100);

- to compare and verify the correctness of the angular positions detected with respect to what was expected in the data and times memorized in said electronic memory containing the programmable data and times base (101).
Method as in claim 1 or 2, characterized in that it provides to effect by means of said central unit (100) and based on the information associated with said angular position values and detected in the course of the control and on the information of the data and times memorized in said electronic memory containing the programmable data and times base (101):
I) a verification, for each of said pairs (A-B1; A-B2; A-B3; A-B4; A-Bn) of step-wise servomotors (71A, 71B), if in a reciprocal start movement of a first (A) of the step-wise servomotors of the pair and exit of a second (B1, B2, B3, B4, Bn) of the step-wise servomotors of the pair there is interference and, if positive:
I.a) a comparison between the stop position (YstopA) of the first step-wise servomotor (A) with the expected position of the second step-wise servomotor (B1, B2, B3, B4, Bn) of the pair after a minimum stop time (TstopA) of the first step-wise servomotor (A) and, if the positions are interfering, to stop the two step-wise servomotors or, if the positions are not interfering, to repeat the cycle from the start;
whereas, if negative,
I.b) a verification for said pair of step-wise servomotors, if in a reciprocal start movement of the second (B1, B2, B3, B4, Bn) of the step-wise servomotors of the pair and exit of the first (A) of the step-wise servomotors of the pair there is interference and, if positive,
I.b.i) a comparison between the stop position (YstopB) of the second step-wise servomotor (B1, B2, B3, B4, Bn) with the expected position of the first step-wise servomotor (A) of the pair after a minimum stop time (TstopB) of the second step-wise servomotor (B1, B2, B3, B4, Bn) and, if the positions are interfering, to stop the two step-wise servomotors or, if the positions are not interfering, to repeat the cycle from the start;
whereas, if negative:
I.b.ii) a comparison between the stop position (YstopB) of the second step-wise servomotor (B1, B2, B3, B4, Bn) with the actual position (YactualA) of the first component (A) of the pair after a minimum stop time (TstopB) of the second step-wise servomotor (B1, B2, B3, B4, Bn) and, if the positions are interfering, to stop the two step-wise servomotors, or, if the positions are not interfering, to repeat the cycle from the start.
Method as in claim 1, 2 or 3, characterized in that it provides to effect by means of said central unit (100) and according to information on the electric current received by current sensor means associated with each servomotor (71 A, 71B) and on the information on data and times memorized in said electronic memory containing the programmable data and times base (101):
II) a verification, by means of electronic comparison and control means (102) for each of said pairs (A-B1; A-B2; A-B3; A-B4, A-Bn) of step-wise servomotors if the electric current absorbed by a corresponding servomotor (71) of the pair in the respective actual positions (YactualA, YactualB) of the first (A) and the second (B1, B2, B3, B4, Bn) step-wise servomotor is outside a predetermined threshold range and, if positive, to stop the two step-wise servomotors or, if negative, to repeat the cycle.
Method as in any claim from 1 to 4, characterized in that it provides to effect, by means of said central unit (100):
III) a verification for each of said pairs (A-B1; A-B2; A-B3; A-B4, A-Bn) of step-wise servomotors if serious errors have occurred in the first step-wise servomotor of the pair and in the second step-wise servomotor of the pair, said serious errors being selected from a group comprising: failure in activation, break-down in activation, breakage of the cable on the bus propagating the positions, breakage of the transducer on the servomotor, breakdown of the servomotor, breakdown of the central unit (100).
Method as in any claim from 1 to 5, characterized in that in the event of an absence of said material in a given controlled position of a determinate operating unit (22, 25, 26, 27, 34, 37), or in the event of an absence, or unexpected presence, of a specific operating part of one of the operating units (22, 25, 26, 27, 34, 37), said method actuates:
- an overall stoppage of the machine (1), or

- a stoppage of the operating unit (22, 25, 26, 27, 34, 37) controlled and the units upstream thereof, while the operating units (22, 25, 26, 27, 34, 37) downstream and the wrapping wheel (13) are made to operate until the subsequent units downstream of the unit controlled are emptied.
Command and control apparatus to control a packing machine (1) of finished packets (3) of smoking articles, extending along a single substantially vertical plane and having a central wrapping wheel (13) and at least two of the following operating units (22, 25, 26, 27, 34, 37):
- a movement unit (9) suitable to feed said smoking articles toward said wrapping wheel (13) along a substantially horizontal direction of movement (M) parallel to an axis of rotation (R) of said wrapping wheel (13);

- a positioning unit (25) suitable to position sequentially a plurality of small collars (6) moving them in a radial direction with respect to said wrapping wheel (13) toward peripheral drawers (14) of said wrapping wheel (13);

- a first transfer unit (22) suitable to transfer in a radial direction with respect to said wrapping wheel (13) said smoking articles already wrapped by an internal wrapping sheet (4), taking it from said movement unit (9);

- a second transfer unit (27) suitable to deliver an external wrapping sheet (8) in a radial direction into said peripheral drawers (14) of said wrapping wheel (13);

- a wheel type final packaging and wrapping unit (34) suitable to receive radially from said wrapping wheel (13) the material introduced therein on each occasion so as to form said packets (3);
wherein said command and control apparatus comprises a central command and control unit (100) of the programmable type associated to an electronic memory containing a programmable data and times base (101) which contains information relating at least to one or more work cycles to be carried out,
characterized in that it also comprises a first step-wise servomotor (71A) associated with said wrapping wheel (13) and at least two second step-wise servomotors (71B) each associated to one of said at least two operating units (22, 25, 26, 27, 34, 37), wherein each of said first and second step-wise servomotors (71 A, 71B) is provided with a position transducer and is controlled by said central command and control unit (100) of the programmable type, so that said first step-wise servomotor (71 A) associated with said wrapping wheel (13) is combined for the purposes of the control and command in a bidirectional and independent manner with at least one of said two second step-wise servomotors (71B) of said operating units (22, 25, 26, 27, 34, 37), said central unit (100) being configured to determine, for each pair (A-B1; A-B2; A-B3; A-B4; A-Bn) that is created between said first step-wise servomotor (71A) and one of said second step-wise servomotors (71B), a univocal and bidirectional dialog, which is assisted by said central unit (100), on the basis of the data and times memorized in said electronic memory containing the programmable data and times base (101) and the information supplied by the position transducers of the step-wise servomotors (71 A, 71 B) involved, so that the information supplied by said transducers and associated to said dialog are compared by said central unit (100) with the information contained in said electronic memory containing the programmable data and times base (101) in order to verify their conformity with the corresponding work cycle to be carried out,
wherein said operating units (22, 25, 26, 27, 34, 37) comprise one or more presence sensors suitable to detect the presence of material in one or more of said operating units (22, 25, 26, 27, 34, 37) and/or the presence or absence of a specific operating part of one of the operating units (22, 25, 26, 27, 34, 37) and/or of said central wrapping wheel (13), said presence sensor means being associated with said central unit (100),
wherein said central command and control unit (100) is configured to effect, by means of said presence sensors, for each of said pairs (A-B1; A-B2; A-B3; A-B4, A-Bn) of step-wise servomotors, a first verification of the presence of a determinate material selected from among one or the other of said organized group of smoking articles, first (4) and second (8) wrapping sheet and collar (6) on a first component (A) of the pair of step-wise servomotors and/or the presence or absence of a specific operating part of one of said operating units (22, 25, 26, 27, 34, 37) and/or said central wrapping wheel (13) and, if positive, a second verification of the presence of a coordinated material selected from one or the other of said organized group of smoking articles, first (4) and second (8) wrapping sheet and collar (6) on a second step-wise servomotor (B1, B2, B3, B4, Bn) of the pair and/or the presence or absence of a specific operating part of one of said operating units (22, 25, 26, 27, 34, 37) and/or said central wrapping wheel (13) and in a further positive case to start the work cycle, whereas in a negative case for the first or the second verification to repeat the control cycle from the start.
Apparatus as in claim 7, characterized in that each of said step-wise servomotors (71 A, 71B) comprises or is associated with its own current sensor means communicating with said central unit (100), and in that said central unit (100) comprises electronic comparison and control means (102) associated with said electronic memory containing the programmable data and times base (101).
Apparatus as in claim 7 or 8, characterized in that said central command and control unit (100) is configured to actuate, in the event of an absence of said material in a given controlled position of a determinate operating unit (22, 25, 26, 27, 34, 37), or in the event of an absence, or unexpected presence, of a specific operating part of one of the operating units (22, 25, 26, 27, 34, 37):
- an overall stoppage of the machine (1), or

- a stoppage of the operating unit (22, 25, 26, 27, 34, 37) controlled and the units upstream thereof, while the operating units (22, 25, 26, 27, 34, 37) downstream and the wrapping wheel (13) are made to operate until the subsequent units downstream of the operating unit (22, 25, 26, 27, 34, 37) controlled are emptied.
Packing machine comprising a command and control apparatus as claim 7, 8 or 9.