Method and device for cutting tying bands of stacks or packs of labels or blanks

Abstract: A method for cutting tying bands (whether of paper or plastic film) of stacks or packs of labels foresees that the band (F) is cut according to a transversal cutting line (T). The invention foresees before the execution of the cut of the band the separation of the same from the stack (P) in the area where the cut takes place by laterally deflecting a part of the labels or the blanks, in order to form a groove (G) for the cutting knife (11) to pass through avoiding certainly interferences between the same and the labels or blanks in the area of the cutting line (T). The invention relates to a device for carrying out the said method and for incorporation of the device in a packing machine especially in cigarette packing machines or similar.

Description: The invention relates to a method for cutting tying bands of stacks or packs of labels or blanks by moving a cutting knife transversally to the tying bands along a cutting line, comprising the following steps: a) feeding at least one stack or pack of blanks or labels to a cutting station in a position, in which the cutting line of the tying band is provided in the range of a lateral face of the stack or pack transversally to which the tying band extends, b) distancing the tying band from the stack or pack of blanks or labels by laterally deflecting a part of the labels or blanks of the stack or pack in order to permit the passage of the cutting knife avoiding certainly interferences of the knife with the labels or blanks in the area of the cutting line, c) execution of the cut by means of a relative motion of the cutting knife with regards to the tying band (F) of the stack or pack, according to the pre-characterizing part of claim 1. A method of this kind is known from the document EP 0 381 634 A. According to the method known from the document EP 0 381 634 A the tying band is distanced from the stack or pack of blanks or labels by raising at least one of the two opposite ends of a horizontally positioned stack or pack, so as to deflect laterally the blanks or labels at the raised end and consequently to render concave the upper side of the stack or pack in correspondence with which the tying band is spaced from the blanks or labels. According to the document GB 2 076 355 A, a paper sheet bundle is bent about its longitudinal axis so that a part of the tying band is stretched over a concave portion of the bent paper sheet bundle in the form of a chord. The invention has the aim to create a method for cutting tying bands that ensures a reliable cut, fast and without danger of ruining the labels or blanks of the stack or pack tied by the band, consenting to carry out the method with relatively simple, not cumbersome and low cost means. The invention attains these aims with a method according to the pre-characterizing part of claim 1 and characterized by the fact that that the distancing of the tying band from the stack or pack is effected by pushing the part of the labels or blanks in the area of the cutting line in direction of a rear stop surface which has a recess to house and stop the stroke of deflection of the pushed part of the labels or blanks and retains in place the other labels or blanks thus forming a groove in the stack or pack for the passage of the cutting knife. The method according to the invention is applied to tying bands whether of paper or plastic film or of any other material. The invention relates also to a device for carrying out the said method, comprising: d) a cutting station; e) pick up and feeder means for feeding to the cutting station at least one stack or pack of blanks or labels held together by at least one tying band; f) means for holding said stack or pack in a position, in which the cutting line of the tying band is provided in the range of the lateral face of the stack or pack transversally to which the tying band extends; g) a cutting knife movable relatively and transversally with regards to the tying band of the stack or pack along the cutting line; h) means for distancing the tying band from the stack or pack by a lateral deflection of a part of the labels or blanks in order to permit the passage of the cutting knife avoiding certainly interferences of said knife with the labels or blanks in the area of the cutting line, according to the pre-characterizing part of claim 7. A device of this kind is also known from the aforesaid document EP 0 381 634 A. The device according to the invention is characterized by the fact that the means for distancing the tying band comprise: i) pusher means for pushing the part of the labels or blanks in the area of the cutting line in the direction of the lateral deflection and movable with a reciprocating motion with regards of the stack or pack alternately with the motion of the cutting knife, and j) stopping means provided in a rear stop surface on the side of the stack or pack opposite to the pusher means and formed by a recess to house and stop the stroke of deflection of the part of the labels or blanks that are deflected relative to the stack or pack. The device according to the invention preferably comprises further means of realignment of the stack or of the pack in the initial conditions after the execution of the cut that are formed by mobile plungers of realignment acting in the opposite direction to the one of the deflecting plungers. Advantageously also in this case, the pusher means of realignment of the stack or pack are provided in combination with stop surfaces of realigment on the opposite side, or on the side of the stack or pack on which act the means of deflection. The means of deflection and their means of realignment control and/or the control locator of the deflection and the pusher means of realignment are such that these act alternatively between each other. Apart from the means of realignment of the blanks or of the labels in a position overlapping each other and in a direction transversal to the cutting line the device has advantageously also means of realignment in one or more directions substantially parallel or in any case with a considerable component parallel to the cutting line according to the geometric shape of the layout of the label or the blank. In particular with rectangular, or square labels or blanks or that in any case have edges on the two opposite sides perpendicular to the line of cut, the invention provides means of realignment also in the direction of the actual cutting line. The device can furthermore have in combination with the means described above also means for clamping the stack or pack of labels or blanks in the perfectly realigned condition and that are activated after the realignment sequence and remain active during the sequence of discharge or of exit from the cutting station. According to one preferred form of execution, the stopping or limiting means of the deflection of the part of the labels or blanks in order to generate a groove for passage of the cutting knife, the realignment means of the labels or blanks relatively to the part of the same subjected to deflection for generating the groove for passage of the cutting means and the clamping means in the realigned position of the stack or pack as well as the drive actuators are integrated in the feeding means of the stack or pack at the cutting station. A preferred executive example, provides for said feeding means to be constituted in their more complex form, but not necessarily limitative, as it is possible to provide also subcombinations, from a conveyor stirrup supported movable along guides on at least a twodimensional track, preferably threedimensional and the said stirrup has a ledge for supporting the stack or pack, preferably designed to support the stack or pack in the central area, a series of pressure clamps opposite to the supporting ledge and drivable to move in the two directions in the direction of drawing nearer to and moving away from the said ledge, a supporting wall on the side of the stack or pack opposite to the one along which the band is cut and that has a channel or a groove to house and limit the end of stroke of the deflection of the part of the labels or blanks that is deflected relative to the remaining labels or blanks of the stack or pack and at least one reciprocating pusher, preferably a pair of reciprocating pushers, on the two sides of the supporting wall of the stack or pack on the opposite side of the band cutting area respectively, the said pushers have a flat surface that in the active position extends itself perfectly in line with the said supporting wall also in the area housing and limiting the end of stroke of the part of deflected labels or blanks and which is oscillated back in inactive position and extends itself at least in the area of the said groove, behind the actual groove with regards to the direction of deflection of the corresponding part of labels or blanks. The cutting knife is housed together with the pusher means of deflection and with the alternating stop surface of realignment in direction of the deflection and together with eventual means of alignment in direction transversal to the one of the cut, in a cutting unit that comprises as well all the drive actuators of said means and that in turn is fitted movable between an active position and an inactive position in the cutting area of the band. Such a group is preferably mounted on guides perpendicular to the face of the stack that has the section of the band to be subjected to the cutting, while it is being moved between a position of coming to rest against the said face of the stack or pack and an inactive position moving away from the same. The actuators of all the units in motion provided are preferably of the pneumatic, hydraulic type or of a mechanical type and driven by an electric motor. The invention has further features that are subject of the claims below. The features of the invention and the advantages arising from the same will be better evidenced in the following description of an executive example illustrated as a non limiting claim in the enlcosed drawings, in which: The Fig.s 1 and 2 illustrate in perspective a station for cutting tying bands F of stacks or packs P of blanks, in particular of blanks for making rigid cigarette packets, or similar. The Fig.s 3 to 9 illustrate different views of pick up and feeding means of a stack P of blanks respectively in the various sequences of pick up and feeding of a stack P to the cutting unit and the preperation for cutting of the band itself. The Fig. 10 illustrates an enlarged detail of the stack P during the cutting sequence of the band. The Fig.s 11 and 12 illustrate a transversal cross section of the cutting unit with the means of deflection of a part of the blanks provided in the area of the cutting line, in the active position and in the position of rest respectively. The Fig. 13 illustrates a frontal view of the cutting unit. The Fig.s 14 to 18 illustrate different sections of the cutting unit according to a plane parallel to the cutting line and in different sequences of the deflection process of part of the blanks of the stack and of the cutting of the band. The Fig.s 19 and 20 illustrate a plan view from above of the means of alignment of the stack in direction parallel to the cutting line in the position of rest and in the active position respectivley. The Fig.s 21 to 23 illustrate tranversal cross sections in the different operative positions of an executive variant of the means for the deflection of a part of the blanks. The Fig.s 24 and 25 are two frontal views of the group according to the Fig.s 21 and 23 with the means for the deflection of a part of the blanks in the active and inactive positions. With reference to the figures, for example in a cigarette packing machine, or similar, feeding means are provided, for example a pair of conveyor bands 1 parallel and distanced between each other of a sequence of stacks P of blanks, each of these stacks is tied by a band F. The stacks of blanks P are picked up one at the time from the discharge end of the pick up/feeder conveyors 2 that are movable along the guides 3, 7, for example a bridge type structure according to two directions in a vertical plane and that carry one at the time each stack P to the cutting station S arranged laterally deflected with regards to the conveyor 1. After the cutting of the band the pick up/feeder 2 carries the stack P to a feeding station on the manufacturing machine, in this case a packing machine depositing it in a hopper (not shown in detail, but that for example can be arranged beside the cutting station). A cutting group overall indicated with 4 is provided in the cutting station and that is housed in a box 104 movable to-and-fro in position of moving away from and approach to the stack P waiting on the pick up/feeder means 2 that form also the means of support of the pack during the cutting operation itself. The box 104 of the cutting group 4 is mounted on horizontal guides 5 and is moved along the same by an actuator 6 that can be of any type, for example pneumatic or hydraulic or oleodynamic. The pick up/feeder means 2 are formed by a ledge attached overhanging to a carriage 3 movable in particular in direction parallel to the cutting and the horizontal line, the guide 103 of this carriage is in turn mounted vertically slidable on vertical guides 7, in particular at its opposite ends. The ledge of the pick up/feeder means of the stacks P comprises a lower horizontal support plane 102 to which a vertical wall 202 is connected. The vertical wall 202 is intended to form a stop surface for the stack P opposite to the side of the stack P along which the cutting line of the band F is provided, becoming, for simplicity, in the text and in the claims the side of the stack P opposite to the line of cut defined as the back to the one in correspondence to which the cutting line indicated with T is foreseen and defined as front. The lower plane of support 102 and the stop wall 202 form an L shaped stirrup and are rigidly connected to each other. The free end of the rear stop wall 202 is hinged in an oscillatory manner on an axis 8 parallel to the cutting line T at the bottom end of the pick up/feeder 2 structure. An actuator 9 articulated with one extremity to a rear projection 302 of the upper end of articulation of the rear stop wall 202 and with the other end at the lower extremity, provided in the area of the support plane 102, of a stirrup 402 drives the oscillatory motion of the support plane 102 and rear wall 202 asembly. The rear stop wall 202 has a transversal groove 502 that extends itself over the entire extension of the same. The groove 502 is foreseen at a level corresponding to the one of the cutting line T and has a greater depth than the part of the knife or of the cutting means projecting beyond the band F on the side facing the blanks F of the stack P. Two pushers of re-alignment 602 are provided beside the two lateral sides of the rear stop wall 202 that are supported by the rear stop wall 202 itself in an oscillatory manner around an axis parallel to the one of oscillation of the rear stop plate 202. The two pushers of realignment 602 are made in form of an inverted L, with a branch parallel to the rear stop wall 202 and a transversal branch and are fulcrated in the corner area in such a manner as to assume thanks to the linear actuators 802 a position of alignment with the face of the rear stop wall 202 against which the stack P comes into contact and a position angularly displaced to the rear in a measure at least equal to the maximum depth of the groove 502. Obviously the pushers of realignment 602 extend themselves with their vertical branch into the area of the groove 502 and possibly also slightly beyond the same. The width or horizontal extension of the rear stop wall 202, the pushers of re-alignment 602 and the support plane 202 included is inferior to the one of the stack P and extends istself substantially in the central area of the stack P or in any case in the area of the band F. In a position overlapping the support plane 102, the pick up/feeder means 2 have a support ledge 20 of one or more, pushers 21 that act perpendicularly at the top end of the stack P, clamping the same into position. The pusher 21 drivable by linear, pneumatic, hydraulic or other type of pushers can be raised from a position distanced from the top end of the stack P and can be lowered against the stack P on which they can exert a preset pressure to clamp the stack between the same and the support plane 102. Preferably the pushers act in the area of the band F, in that they hold the same against the stack P after the cut. The cutting unit 4 comprises a box 104 inside of which are provided a first carriage group, slide guide and drive actuator 10 that carries a knife 11. The group carriage-slide guide-actuator 10 is of the integrated type and easily found commercially. The carriage 110 of the same carries the rotyary drive motor 111 of a rotary knife 211 and a fork 311 provided with a central pass-through slot for the knife blade 211 and that has a certain inclination in the horizontal plane relative to the line of cut and is intended to overlap behind the band F during the actual cutting forming a surface of support of the area of the band along which the cut T is applied. Advantageously the fork extends itself according to a secant plane relative to the knife 211 the peripheral area of which passes through the central slot of the same. Furthermore the fork is made wedge-shaped, forming a surface of silght tension and progressive conveyance with the advancement of the knife 211 in an angled area between the cutter and the wall of the fork 311 itself. The knife 11 is movable outwards from a position of rest in which it is completely covered into an active position, in which it projects outwards towards the stack P that is facing towards a slot 204 of the box 104 that extends itself in a front stop wall 304 of the said box 4 for the entire length of the active stroke of the knife. In the box 104 of the cutting unit 4 further pushers 12 are provided for the deflection of a part of the blanks of the stack P which is contained within a certain tollerance in the area of the cutting line above and below the same. Preferably two or more deflection pushers 12 are provided that are distanced between each other parallel to the direction of the cut and to the groove 502 of the pick up/feeder means of the stack P. The distance of the deflection pushers 12 is such that in the presence of stacks P of blanks of different size, at least one of the deflection pushers 12 comes to engage with the stack P. The pushers 12 are equipped with a pusheer head 112 with a shape substantially corresponding to the transversal cross section of the groove 502 in the stop wall 202 of the pick up/feeder means 2. Advantageously the curvature or radial bend of the pusher head 12 is such as to obtain a minimum relative motion of the blanks one with regards to the other. Thanks to this, also blanks with particular paddings do not risk sticking to each other. In an alternate or intermediate position between two or more deflection pushers 12 a stop wall of realignment 13 is foreseen that is movable into active position and inactive position and that in the said inactive position is aligned with the front stop wall 204 of the box 104 of the cutting unit 4. The deflection pushers 12 and the stop wall of realignment 13 are mounted movable in active and inactive position. In the active postion these extend themselves beyond and in line with the front stop wall 204 of the box 104, while they are retracted in the inactive position into the box in position of nonengagement with the knife 11. This is carried out thanks to the actuators 14. It is possible to make the deflection pushers 12 and the stop wall of realignment to carry out different types of motions. In the executive forms of Fig.s 11 to 18, the deflection pushers 12 and the stop wall of realignment 13 are mounted on the same linear actuators 14 and are permanently mounted in a position coinciding with the slot 304. The stroke of the actuators is such, whereby in the inactive position completely retracted into the box 104, the deflection pushers 12 and the stop wall of realignment 13 are outside of the sliding path of the knife 11 and do not engage with the same. In the executive form of the Fig.s 21 to 25, in order to reduce the stroke of the linear actuators in perpendicular direction to the facing side of the stack P, the actuators are mounted on a ledge 15 fitted on vertical guides 11 and projecting staggered in the area of passage of the knife 11, the said ledge is alternatively raised and lowered into a position in where the deflection plungers 12 and the stop wall of realignment 13 are coincident with the slot 304 and in a position in which said parts 12, 13 are raised relative to the slot 304 in a distanced position of noninterference with the stroke of the knife 11. The raising and lowering of the ledge 15 takes place thanks to linear actuators that can be like the ones used for the parts 12 and 13 or for the motion of the knife 11. Two parts of realignment of the stack P according to the direction parallel to the cutting line T are carried staggered from above in front of the front stop wall 304 of the box 4. The parts of realignment consist of vertical elements 18 that extend themselves for the entire height of the stack P and the top end of which is fixed to the projecting end of a support arm 116 that links with or is formed by a lateral extension of a respective sliding carriage 216 mounted slidable on two guides 17 parallel to each other and with regards to the cutting line. Between the two guides 17 in the intermediate area between the two carriages 216 two linear actuators 18 are foreseen that drive the motion of the two vertical elements 16, in such a manner that the same are moved away from or moved towards each other symmetrically relative to the median transversal axis of the stack P. The two vertical elements, have stop walls 306 with the end sides of the stack P perpendicular to the cutting line T and parallel to each other that are oriented correspondingly to the areas of contact with said end sides of the stack P. The stroke of the parts of realignment 16 in direction of the cut is such, whereby they can be distanced in a measure larger than the maximum dimension of the blanks in direction of the cutting line and can be brought to abut against the corresponding end sides of the stack P with minimum dimensions in direction of the cutting line T. The operation of the device becomes evident from the sequences shown in the figures. A stack P tied with a band F is picked up from the double band type conveyor 1, by bringing the pick up/feeder 2 with the rear stop wall 202 and the support plane 102 between the two bands at a level of vertical alignment with a stack P at the discharge end of the conveyor 1 and in a position behind the said stack with reference to the direction of advance on the conveyor 1. The support plane 102 with the rear stop plate 202 oscillates from said inclined rear position into the forward position the stack P is picked up in a position with its rear side resting against the rear stop wall 202 and placed on the support plane 102. By activating the pushers 21, the stack P is clamped and then the pick up/feeder means 2 carry the same in a preset position with the vertical side free in front of the front stop plate 204 of the box 104 of the cutting unit 4. The box is made to advance and brought to abut against the corresponding side of the stack P, then the pushers 21 are moved away, or the pressure applied by the same is reduced to the extend that it allows for the activation of the deflection pushers 12 which are pushed through the slot 304 against the side of the stack P. The deflection pushers move laterally a group of blanks contained astride the cutting line T and that abut on the opposite side against the groove 502 in the rear stop wall 202 thus forming a throat G in the stack of blanks along which the band F is free on the back and that is of such dimensions as to allow for the knife 11 and its associated fork to pass through without the said two parts coming to interfere with the blanks themselves. The Fig. 10 and the Fig. 18 illustrate the cutting condition on an enlarged scale. The deflection pushers 12 are withdrawn into position of nonengagement with the knife, therefore the pushers 21 are eventually reactivated and the knife 11 carries out the cutting stroke as shown in Fig.s 16 and 18, rerturning at the end to the starting position. Subsequently, releasing again the pressure of the pushers 21 they are oscillated into active position of realignment, that is in a position aligned level with the rear stop wall 202 of the pick up/feeder means 2, the associated realignment pushers 602, while the stop plate of realignment 13 is pushed against the opposite side. In this manner the deflection of the blanks of the stack P is recovered in a direction perpendicular to the cutting line T and thanks to which a through channel was created for the knife 11 and for the associated means. At the same time or in succession the vertical elements of realignment 16 of the stack P are brought nearer in direction parallel to the one of the cut T against the head of the stack P. The stack is again perfectly realigned and after having reactivated the clamping pushers, the pick up/feeder means carry the stack P to the subsequent station feeding the same to the manufacturing machine, which is in this example a cigarette packing machine. The procedure is repeated for each stack P, as all the individual units are returned to their corresponding starting positions. From the description above the great simplicity of the means and of the units used for carrying out the cutting method are clearly evident. Such simplicity guarantees low manufacturing costs and reliable operation as well as a considerable speed of execution of the procedures. The simple cutting procedure of the band has been advantageously integrated with the functions of realignment and setting the stack that renders the subsequent feeding steps of the stack to the manufacturing machine more reliable and less subject to jams. The cut is carried out without the danger of damaging the blanks and therefore reduce the quantity of rejects, while the realignment avoids blanks incorrectly positioned that can lead to jams or stops in the feeding cycle in which the blanks are generally separated one after the other from the stack itself. Naturally the invention is not limited to the executive forms herein described and illustrated but can be amply variated above all constructively without for this abandoning the scope of the invention as defined by the appended claims.

Claims: Method for cutting tying bands (F) of stacks or packs (P) of labels or blanks by moving a cutting knife (11, 111, 211, 311) transversally to the tying bands (F) along a cutting line (T), comprising the following steps: a) feeding at least one stack or pack (P) of blanks or labels to a cutting station (S) in a position, in which the cutting line (T) of the tying band (F) is provided in the range of a lateral face of the stack or pack (P) transversally to which the tying band (F) extends, b) distancing the tying band (F) from the stack or pack (P) of blanks or labels by laterally deflecting a part of the labels or blanks of the stack or pack (P) in order to permit the passage of the cutting knife (11) avoiding certainly interferences of the knife with the labels or blanks in the area of the cutting line (T), c) execution of the cut by means of a relative motion of the cutting knife (11) with regards to the tying band (F) of the stack or pack (P), characterized by the fact that the distancing of the tying band (F) from the stack or pack (P) is effected by pushing the part of the labels or blanks in the area of the cutting line (T) in direction of a rear stop surface (202) which has a recess (502) to house and stop the stroke of deflection of the pushed part of the labels or blanks and retains in place the other labels or blanks thus forming a groove (G) in the stack or pack (P) for the passage of the cutting knife (11). Method according to claim 1, characterized by the fact that it provides for the realignment (602, 13) of the stack or pack (P) after the cut of the band (F) has been carried out. Method according to claim 2, characterized by the fact that it foresees the clamping (20, 21) of the stack or pack (P) in the realigned condition and the discharge from the cutting station (S). Method according to one or more of the preceding claims, characterized by the fact that the band (F) is at least supported on the two sides of the cutting line (T) on the side opposite to the one of the cutting knife (11). Method according to one or more of the preceding claims, characterized by the fact that the band (F) is progressively slightly tensioned and guided (311) against the knife (211) with the advancement of the knife (211) along the cutting line (T), being supported at the back by a part (311). Method according to one or more of the preceding claims 2 to 5, characterized by the fact that the realignment is carried out also according to directions transversal to the one of deflection, in particular in the direction parallel to the cutting line (T). Device for carrying out the method according to one or more of the preceding claims, comprising: d) a cutting station (S) ; e) pick up and feeder means (2) for feeding to the cutting station (S) at least one stack or pack (P) of blanks or labels held together by at least one tying band (F) ; f) means for holding said stack or pack (P) in a position, in which the cutting line (T) of the tying band (F) is provided in the range of the lateral face of the stack or pack (P) transversally to which the tying band (F) extends; g) a cutting knife (11, 111, 211, 311) movable relatively and transversally with regards to the tying band (F) of the stack or pack (P) along the cutting line (T) ; h) means for distancing the tying band (F) from the stack or pack (P) by a lateral deflection of a part of the labels or blanks in order to permit the passage of the cutting knife (11, 111, 211, 311) avoiding certainly interferences of said knife with the labels or blanks in the area of the cutting line (T), characterized by the fact that the means for distancing the tying band (F) comprise: i) pusher means (12, 112, 14, 15, 115) for pushing the part of the labels or blanks in the area of the cutting line (T) in the direction of the lateral deflection and movable with a reciprocating motion with regards of the stack or pack (P) alternately with the motion of the cutting knife (11, 111, 211, 311), and j) stopping means (505) provided in a rear stop surface (202) on the side of the stack or pack (P) opposite to the pusher means (12, 112, 14, 15, 115) and formed by a recess to house and stop the stroke of deflection of the part of the labels or blanks that are deflected relative to the stack or pack (P). Device according to claim 7, characterized by the fact that it comprises further means of realignment (602) of the deflected part of blanks of the stack or pack (P) to the starting condition after the cut has been carried out and that are formed by moving realignment pushers acting in the opposite direction of the deflection pushers (12, 212). Device according to claim 8, characterized by the fact that the pusher means of realignment (602) of the stack or pack (P) are provided in combination with stop surfaces of realignment (13) on the opposite side, or on the side of the stack or pack (P) on which act the means of deflection (12, 112). Device according to one or more of the preceding claims 7 to 9, characterized by the fact that the means of deflection (12) and the stop means of realignment (13) and/or the deflection stops (502) and the pusher means of realignment (602) are such that they act alternately between each other. Device according to one or more of the preceding claims 7 to 10, characterized by the fact that apart from the means (602, 13) of realignment of the blanks or labels in a position overlapping each other and in a direction transversal to cutting line (T) means (16, 17, 18) are provided for realignment in one or more directions transversal to the direction of deflection, according to the geometric shape of the label or blank layout. Device according to claim 11, characterized by the fact that it is provided in combination with rectangular, or square blanks, or that anyhow present perpendicular edges to the cutting line (T) at the two opposed extremities, and has means of realignment (16, 17, 18) also in direction of the cutting line (T) itself. Device according to one or more of the preceding claims 7 to 12, characterized by the fact that it has adjustable means (20,21) for clamping the stack or pack (P) of labels or blanks in the condition of perfect realignment and that are activated at least after the realignment cycle and remain active during the discharge or exit cycle from the cutting station (S). Device according to one or more of the preceding claims 7 to 13, characterized by the fact that the stopping means to limit the deflection (502) of part of the labels or blanks to create a groove (G) for passage of the cutting knife (11, 211, 311), the means of realignment (602) of the labels or blanks relative to the part of the same subjected to deflection to generate the groove of passage (G) and the clamping means (20, 21) in position of realignment of the stack or pack (P) as well as the drive actuators (9, 802) are integrated with the feeding means (2) of the pack or stack (P) at the cutting station (S). Device according to one or more of the preceding claims 7 to 14, chracterized by the fact the the pickup/feeder means comprise a conveyor stirrup supported movable along a guide on a at least bidimensional track and the said stirrup has a supporting ledge (102) of the stack or pack (P) preferebly intended to support said pack or stack (P) in the middle section or in correspondence of the band (F), the said ledge has a series of clamping pushers (20, 21) opposite to the support ledge and can be driven moving in two directions of moving nearer to and away from the said ledge (102), a stop wall (202) of the side of the stack or pack (P) opposite to the one along which the band (F) is cut and the same wall (202) has a channel or a groove (502) for housing and stopping the stroke of deflection of the part of the labels or blanks on which act the deflection plungers (12, 112) and at least one plunger, preferably a pair of realignment plungers (602, 802). Device according to claim 15, chracterized by the fact that the realignment plungers (602, 802) are supported by the rear stop plate (202) of the pick up/feeder means (2) and are provided each on one of the two sides of the stop wall (202). Device according to claim 16, characterized by the fact that the realignment plungers (602, 802) are supported oscillating and have a flat surface that in active position extends perfectly aligned with said stop plate (202) and extends itself also in the area of the groove stopping the deflection (502), while in the inactive position they are angularly moved into such a position that the full surface of the same extends itself in line or recessed with regards to the bottom of the groove or of the recess (502) for stopping the deflection. Device according to one or more of the preceding claims 7 to 17, characterized by the fact that the pick up/feeder means (2) of the stack or pack (P) take up a position of presenting the stack to the cutting unit (4) in the cutting station (S) , while the cutting unit is movable in position of rest and in position of work moving away from and against the stack (P) supported by the pick up/feeder means (2) and has a front stop side (204) that in position of work adheres against the facing side of the stack (P) and which has a slot (304) extending itself in direction of the cut (T) and through which the deflection pushers (12, 112), the stop walls of realignment (13) and the cutting knife (11, 111, 211, 311) come into contact with the stack (P) and/or the band (F). Device according to one or more of the preceding claims 7 to 18, characterized by the fact that the cutting unit (4) has a carriage-guide-actuator (10) with a carriage (110) that is movable in direction of the cut (T) and that carries the knife (211) and the activating means (111) of the same, while the deflection plungers (12, 112) and the stop wall of rialignment (13) ar mounted movable (14, 15, 115) with a motion in one single direction or according to two or three directions from a positon of work readiness to a position of rest, and assume in position of rest a position of non interference with the stroke of the knife (11). Device according to one or more of the preceding claims 7 to 19, characterized by the fact that the cutting knife is of the circular type and rotating (211) and is rotary driven by a motor (111) itself also carried on the carriage (110). Device according to one or more of the preceding claims 7 to 19, characterized by the fact that means of rear support (311) of the area of the band (F) co-operating with the knife (211) itself are connected with the cutting knife (211). Device according to one or more of the preceding claims 7 to 19, characterized by the fact that associated with the knife (211) are means (311) progressively tensioning conveying towards the said knife (211) during the cut the section of the band (F) co-operating with the blade of the knife (211). Device according to claim 21 or 22, characterized by the fact that a fork (311) is associated with the knife (211) that slips with its central slit on the part of the knife (211) destined to engage with the band (F) and that is substantially secant to said knife (211), extending itself in direction of the cut beyond the same in order to overlap the rear of the band (F) at the moment of advancement of the knife (211) and before the same acts on the band (F). Device according to claim 23, characterized by the fact that the knife (211) is circular and the fork (311) is secant to the same and forms on the front side of the knife (211) with reference to the direction of cut (T) an angled area to engage the edge of the band (F). Device according to claim 23 or 24, characterized by the fact that the fork is cuneiform, the peak of the wedge being foreseen in correspondence to the free extremity of the same and the side destined to slide along the rear face of the band (F) made inclined in the direction diverging from the stack (P). Device according to one or more of the preceding claims 7 to 25, characterized by the fact that it has vertical elements (16) of realignment in direction of the cut (T) of the stack (P) which are carried projecting in front of the facing stop plate (204) of the cutting unit (4) by carriages (216) mounted on guides provided above the cutting knife (T) and the deflection plungers (12) and the stop plate of realignment (13), the said guides (17) are parallel with the guides (10) of the knife (11), while said elements (16) carry out a relative motion away from and nearer to that is symmetric with regards to the main axis of the stack (P) in the position of presentation in the cutting station (S). Device according to one or more of the preceding claim 7 to 26, characterized by the fact that the cutting unit (4) is mounted on a carriage sliding on guides (5) and made in shape of a closed box (104). Device according to one or more of the preceding claims 7 to 27, characterized by the fact that deflection plungers (12) and/or more realignment plungers (602) and/or more stop walls of realignment (13) and/or of the strokes of the parts of realigment, are provided, the said elements being arranged or the said strokes being set or can be set in such a manner that stacks of blanks can be handled directly the blanks of which have a shape with substantially identical and different dimensions. Device according to one or more of the preceding claims 7 to 28, characterized by the fact the plunger head (12) has a curvature or radius such to obtain a minimum relative motion of the blanks one relative to the other. Device according to one or more of the preceding claims 7 to 29, characterized by the fact that it is provided in combination with a feeding unit of the blanks of a packing machine, in particular of a cigarette packing machine. Device according to claim 30, characterized by the fact that the feed hopper of the packing machine is provided in a position next to and aligned with the position of presentation of the stack (P) to the cutting unit (4), with reference to one of the directions of translation of the pick up/feeder means (2).

Inventors: MALOSSI STEFANO, SPADA VALTER, MALOSSI, STEFANO, SPADA, VALTER
Applicants: SASIB TOBACCO SPA, SASIB TOBACCO S.P.A.
Application year: 1999
Main classification: B65B69
IPC codes: B65B69