Method and device for producing a cigarette packet

Abstract

A method and device for producing a cigarette packet having an inner wrapping, which is defined by a sheet of heat-seal material folded about a group of cigarettes, and has an opening closed by an adhesive patch; the correct position of the patch is determined after the patch is applied to the sheet of heat-seal material.

1 ) A method of producing a cigarette packet comprising an inner wrapping ( 3 ), in turn comprising a sheet ( 3 ′) of heat-seal material folded about a group (G) of cigarettes to form a wrapped group ( 4 ) of cigarettes; and an outer container ( 5 ), preferably of thin cardboard, folded about the wrapped group ( 4 ) of cigarettes; the method comprising: 
 a feed step to feed a strip ( 9 ) of heat-seal material along a feed path (P);    a step of forming a slit ( 6 ) in the strip ( 9 );    a first application step to apply an adhesive patch ( 7 ) onto the slit ( 6 );    a cutting step to cut said sheet ( 3 ′), complete with the slit ( 6 ) and the patch ( 7 ), off the strip ( 9 );    a folding step to fold the sheet ( 3 ′) about the group (G) of cigarettes to form the wrapped group ( 4 ) of cigarettes;    a sealing step to seal superimposed portions (T) of the sheet ( 3 ′) folded about the group (G) of cigarettes;    an insertion step to insert the wrapped group ( 4 ) of cigarettes inside the outer container ( 5 );    the method being characterized by comprising a control step to determine correct positioning of the applied patch ( 7 ); the control step preceding the folding step.    
   
   
       2 ) A method as claimed in  claim 1 , wherein the control step precedes the cutting step.  
   
   
       3 ) A method as claimed in  claim 1 , wherein the control step comprises illuminating an area about the slit ( 6 ) with diffused light.  
   
   
       4 ) A method as claimed in  claim 1 , wherein the control step comprises comparing the position of a first edge ( 33 ) of the patch ( 7 ), substantially parallel to the feed path (P), with the position of an edge ( 32 ) of the strip ( 9 ).  
   
   
       5 ) A method as claimed in  claim 4 , wherein the position of the first edge ( 33 ) is determined in at least two separate areas (L 1 , L 2 ) of the first edge ( 33 ).  
   
   
       6 ) A method as claimed in  claim 1 , wherein the control step comprises comparing the position of a second edge ( 34 ) of the patch ( 7 ), crosswise to the feed path (P), with an element ( 31 ) printed on the strip ( 9 ).  
   
   
       7 ) A method as claimed in  claim 1 , wherein, at the feed step, the strip ( 9 ) is fed along the feed path (P) by a conveyor ( 8 ) comprising a suction belt ( 35 ); the first application step being performed at a first application station ( 12 ), through which the suction belt ( 35 ) travels.  
   
   
       8 ) A method as claimed in  claim 1 , and comprising a reject step to reject the sheet ( 3 ′) in the event the patch ( 7 ) is found to be positioned incorrectly at the control step.  
   
   
       9 ) A method as claimed in  claim 8 , wherein the reject step precedes the folding step.  
   
   
       10 ) A method as claimed in  claim 8 , wherein the reject step precedes the sealing step.  
   
   
       11 ) A method as claimed in  claim 1 , and comprising a detecting step, after the first application step, to determine the presence of the patch ( 7 ) on the strip ( 9 ); and a second application step to apply a patch ( 7 ) on the slit ( 6 ) in the event no patch ( 7 ) is detected on the slit ( 6 ) at the detecting step; the second application step preceding the cutting step and following the detecting step.  
   
   
       12 ) A method as claimed in  claim 11 , wherein, at the feed step, the strip ( 9 ) is fed along the feed path (P) by a conveyor ( 8 ) comprising a suction belt ( 35 ); the first and second application step being performed respectively at a first and second application station ( 12 ,  13 ) located along the feed path (P) at the suction belt ( 35 ).  
   
   
       13 ) A method as claimed in  claim 1 , wherein at least one further strip ( 39 ), removably supporting at least one patch ( 7 ), is fed to the feed path (P) in a direction substantially crosswise to the feed path (P).  
   
   
       14 ) A method as claimed in  claim 1 , wherein said superimposed portions (T) are sealed by electromagnetic induction produced by an oscillating electromagnetic field produced by a substantially fixed generator ( 47 ); at the sealing step, movable members ( 48 ) of nonconducting material being brought into contact with the superimposed portions (T) to keep the superimposed portions (T) correctly superimposed; and the sheet ( 3 ′) being made of at least partly conducting material.  
   
   
       15 ) A method as claimed in  claim 1 , wherein the patch ( 7 ) is applied to the strip ( 9 ) by at least one air jet crosswise to the feed path (P) and to a surface ( 25 ) of the strip ( 9 ).  
   
   
       16 ) A method as claimed in  claim 15 , wherein the patch ( 7 ) is maintained parallel to the strip ( 9 ) by suction immediately prior to being applied to the strip ( 9 ).  
   
   
       17 ) A method as claimed in  claim 16 , wherein the patch is held over the strip ( 9 ) by suction, and the air jet blows the patch ( 7 ) downwards onto the slit ( 6 ); the air jet being substantially vertical.  
   
   
       18 ) A method of producing a cigarette packet comprising an inner wrapping ( 3 ), in turn comprising a sheet ( 3 ′) of heat-seal material folded about a group (G) of cigarettes to form a wrapped group ( 4 ) of cigarettes; and an outer container ( 5 ), preferably of thin cardboard, folded about the wrapped group of cigarettes; the method comprising: 
 a feed step to feed a strip ( 9 ) of heat-seal material along a feed path (P);    a step of forming a slit ( 6 ) in the strip ( 9 );    a first application step to apply an adhesive patch ( 7 ) onto the slit ( 6 );    a cutting step to cut the sheet ( 3 ′), complete with the slit ( 6 ) and the patch ( 7 ), off the strip ( 9 );    a folding step to fold the sheet ( 3 ′) about the group (G) of cigarettes to form the wrapped group ( 4 ) of cigarettes;    a sealing step to seal superimposed portions (T) of the sheet ( 3 ′) folded about the group (G) of cigarettes;    an insertion step to insert the wrapped group ( 4 ) of cigarettes inside the outer container ( 5 );    the method being characterized by comprising a detecting step, after the first application step, to determine the presence of the patch ( 7 ) on the slit ( 6 ); and a second application step to apply a patch ( 7 ) on the slit ( 6 ) in the event no patch ( 7 ) is detected on the slit ( 6 ) at the detecting step; the second application step preceding the cutting step and following the detecting step.    
   
   
       19 ) A method of producing a cigarette packet comprising an inner wrapping ( 3 ), in turn comprising a sheet ( 3 ′) of heat-seal material folded about a group (G) of cigarettes; the method comprising: 
 a feed step to feed a strip ( 9 ) of heat-seal material along a feed path (P);    a step of forming a slit ( 6 ) in the strip ( 9 );    an application step to apply an adhesive patch ( 7 ) onto the slit ( 6 );    a cutting step to cut said sheet ( 3 ′), complete with the slit ( 6 ) and the patch ( 7 ), off the strip ( 9 );    a folding step to fold the sheet about the group (G) of cigarettes to form a wrapped group ( 4 ) of cigarettes;    a sealing step to seal superimposed portions (T) of the sheet folded about the group (G) of cigarettes;    the method being characterized in that, at the feed step, the strip is fed along the feed path (P) by a conveyor ( 8 ) comprising a suction belt ( 35 ); the application step being performed at an application station ( 12 ) located along the feed path (P) at the suction belt ( 35 ).    
   
   
       20 ) A method of producing a cigarette packet comprising a wrapping ( 3 ) of heat-seal material; the method comprising: 
 a folding step to fold a sheet ( 3 ′) of at least partly conductive heat-seal material about an article, in particular a group (G) of cigarettes;    a sealing step to seal superimposed portions (T) of the sheet ( 3 ′) folded about the group (G) of cigarettes;    the method being characterized in that said superimposed portions (T) are sealed by electromagnetic induction produced by a variable electromagnetic field produced by a substantially fixed generator ( 47 ); at the sealing step, movable members ( 48 ) of nonconducting material being brought into contact with the superimposed portions (T) to keep the superimposed portions (T) correctly superimposed.    
   
   
       21 ) A method of producing a cigarette packet comprising an inner wrapping ( 3 ), in turn comprising a sheet ( 3 ′) of heat-seal material folded about a group (G) of cigarettes; the method comprising: 
 a feed step to feed a strip ( 9 ) of heat-seal material along a feed path (P);    a step of forming a slit ( 6 ) in the strip ( 9 );    an application step to apply an adhesive patch ( 7 ) onto the slit ( 6 );    a cutting step to cut said sheet, complete with the slit ( 6 ) and the adhesive patch ( 7 ), off the strip ( 9 );    a folding step to fold the sheet ( 3 ′) about the group (G) of cigarettes to form a wrapped group ( 4 ) of cigarettes;    a sealing step to seal superimposed portions (T) of the sheet ( 3 ′) folded about the group (G) of cigarettes;    the method being characterized in that the patch ( 7 ) is applied to the strip ( 9 ) by at least one air jet crosswise to the feed path (P) and to a surface ( 25 ) of the strip ( 9 ).    
   
   
       22 ) A device for producing a cigarette packet comprising an inner wrapping, in turn comprising a sheet of heat-seal material folded about a group (G) of cigarettes to form a wrapped group ( 4 ) of cigarettes; and an outer container ( 5 ), preferably of thin cardboard, folded about the wrapped group ( 4 ) of cigarettes; the device ( 1 ) comprising: 
 a conveyor ( 8 ) for feeding a strip ( 9 ) of heat-seal material along a feed path (P) through a slitting station ( 11 ) and a first application station ( 12 ) to a cutting station ( 10 );    an operating unit ( 15 ) located at the slitting station ( 11 ) to form a slit ( 6 ) in the strip ( 9 );    a first application unit ( 16 ) located at the first application station ( 12 ) to apply an adhesive patch ( 7 ) onto the slit ( 6 );    a cutting assembly ( 42 ) located at the cutting station ( 10 ) to cut said sheet ( 3 ′), complete with the slit ( 6 ) and the patch ( 7 ), off the strip ( 9 );    a folding assembly ( 43 ) for folding the sheet about the group (G) of cigarettes to form the wrapped group ( 4 ) of cigarettes;    a sealing assembly ( 44 ) for sealing superimposed portions (T) of the sheet ( 3 ′) folded about the group (G) of cigarettes; and    a packing assembly ( 50 ) for inserting the wrapped group ( 4 ) of cigarettes inside the outer container ( 5 );    the device ( 1 ) being characterized by comprising a control unit ( 23 ) for determining correct positioning of the patch ( 7 ) on the slit ( 6 ); the control unit ( 23 ) being located upstream from the folding assembly ( 43 ).    
   
   
       23 ) A device as claimed in  claim 22 , wherein the control unit ( 23 ) is located upstream from the cutting assembly ( 42 ) along the feed path (P).  
   
   
       24 ) A device as claimed in  claim 22 , wherein the control unit ( 23 ) comprises a detector ( 24 ); and lighting means ( 26 ,  27 ) for illuminating a surface ( 25 ) of the strip ( 9 ) with diffused light.  
   
   
       25 ) A device as claimed in  claim 24 , wherein the lighting means ( 26 ,  27 ) comprise a cover ( 27 ), a concave surface ( 28 ) of which is positioned facing the feed path (P); and at least two light sources ( 26 ) located on opposite sides of the feed path (P), and which direct light onto the concave surface ( 28 ), which reflects the light to illuminate, in use, the surface ( 25 ) of the strip ( 9 ).  
   
   
       26 ) A device as claimed in  claim 25 , wherein the cover ( 27 ) and the detector ( 24 ) are located over the feed path (P).  
   
   
       27 ) A device as claimed in  claim 24 , wherein the detector ( 24 ) determines the position of edges ( 33 ,  34 ) of the patch ( 7 ).  
   
   
       28 ) A device as claimed in  claim 22 , wherein the control unit ( 23 ) determines the presence of the slit ( 6 ).  
   
   
       29 ) A device as claimed in  claim 22 , and comprising a lighting device ( 29 ) and a detector ( 24 ); the lighting device ( 29 ) and the detector being located on opposite sides of the feed path (P); and the detector ( 24 ) detecting the light travelling through the slit ( 6 ).  
   
   
       30 ) A device as claimed in  claim 22 , wherein the conveyor ( 8 ) comprises a suction belt ( 35 ) for feeding the strip ( 9 ) through the first application station ( 12 ).  
   
   
       31 ) A device as claimed in  claim 22 , and comprising a reject unit ( 52 ) for rejecting the sheet ( 3 ′) on the basis of the findings of the control unit ( 23 ).  
   
   
       32 ) A device as claimed in  claim 22 , and comprising a second application unit ( 17 ) located downstream from the first application unit ( 16 ) along the feed path (P), and which applies the patch ( 7 ) onto the slit ( 6 ) in the event no patch ( 7 ) is applied onto the slit ( 6 ) by the first application unit ( 16 ).  
   
   
       33 ) A device as claimed in  claim 32 , and comprising a detecting unit ( 18 ) located downstream from the first application station ( 12 ) along the feed path (P) to detect the presence of the patch ( 7 ) on the strip ( 9 ); the second application unit ( 17 ) being located downstream from the detecting unit ( 18 ) along the feed path (P), and applying a patch ( 7 ) onto the slit ( 6 ) in the event the detecting unit ( 18 ), in use, detects no patch on the slit.  
   
   
       34 ) A device as claimed in  claim 22 , wherein the first application unit ( 16 ) comprises a feed assembly ( 38 ) for feeding a further strip ( 39 ), removably supporting at least one patch ( 7 ), to the first application station ( 12 ) in a direction substantially crosswise to the feed path (P).  
   
   
       35 ) A device as claimed in  claim 22 , wherein the sealing assembly ( 44 ) comprises at least one oscillating electromagnetic field generator ( 47 ); at least one movable member ( 48 ) of nonconducting material; and actuating means ( 49 ) which move the movable member ( 48 ) into contact with said superimposed portions (T) to keep the superimposed portions (T) correctly superimposed; the generator ( 47 ) being substantially fixed.  
   
   
       36 ) A device as claimed in  claim 22 , wherein the first application unit ( 16 ) comprises blow means for blowing the patch ( 7 ) onto the strip ( 9 ) by emitting at least one air jet crosswise to the feed path (P) and to a surface ( 25 ) of the strip ( 9 ).  
   
   
       37 ) A device as claimed in  claim 36 , wherein the first application unit ( 16 ) comprises suction means for maintaining the patch ( 7 ) parallel to the strip ( 9 ) at the first application station ( 12 ).  
   
   
       38 ) A device as claimed in  claim 36 , wherein the air jet is substantially vertical.  
   
   
       39 ) A device for producing a cigarette packet comprising an inner wrapping ( 3 ), in turn comprising a sheet ( 3 ′) of heat-seal material folded about a group (G) of cigarettes to form a wrapped group ( 4 ) of cigarettes; and an outer container ( 5 ), preferably of thin cardboard, folded about the wrapped group ( 4 ) of cigarettes; the device ( 1 ) comprising: 
 a conveyor ( 8 ) for feeding a strip ( 9 ) of heat-seal material along a feed path (P) through a slitting station ( 11 ) and a first application station ( 12 ) to a cutting station ( 10 );    an operating unit ( 15 ) located at the slitting station ( 11 ) to form a slit ( 6 ) in the strip ( 9 );    a first application unit ( 16 ) located at the first application station ( 12 ) to apply an adhesive patch ( 7 ) onto the slit ( 6 );    a cutting assembly ( 42 ) located at the cutting station ( 10 ) to cut said sheet ( 3 ′), complete with the slit ( 6 ) and the patch ( 7 ), off the strip ( 9 );    a folding assembly ( 43 ) for folding the sheet ( 3 ′) about the group (G) of cigarettes to form the wrapped group ( 4 ) of cigarettes;    a sealing assembly ( 44 ) for sealing superimposed portions (T) of the sheet ( 3 ′) folded about the group (G) of cigarettes; and    a packing assembly ( 50 ) for inserting the wrapped group ( 4 ) of cigarettes inside the outer container ( 5 );    the device ( 1 ) being characterized by comprising a detecting unit ( 18 ) located downstream from the first application station ( 12 ) along the feed path (P) to detect the presence of the patch ( 7 ) on the strip ( 9 ); and a second application unit ( 17 ) located downstream from the detecting unit ( 18 ) along the feed path (P) to apply a patch ( 7 ) onto the slit ( 6 ) in the event the detecting unit ( 18 ), in use, detects no patch ( 7 ) on the slit ( 6 ).    
   
   
       40 ) A device for producing a cigarette packet comprising an inner wrapping ( 3 ), in turn comprising a sheet ( 3 ′) of heat-seal material folded about a group (G) of cigarettes; the device ( 1 ) comprising: 
 a conveyor ( 8 ) for feeding a strip ( 9 ) of heat-seal material along a feed path (P) through a slitting station ( 11 ) and an application station ( 12 ;  13 ) to a cutting station ( 10 );    an operating unit ( 15 ) located at the slitting station ( 11 ) to form a slit ( 6 ) in the strip ( 9 );    an application unit ( 16 ;  17 ) located at the application station ( 12 ;  13 ) to apply an adhesive patch ( 7 ) onto the slit ( 6 );    a cutting assembly ( 42 ) located at the cutting station ( 10 ) to cut said sheet ( 3 ′), complete with the slit ( 6 ) and the patch ( 7 ), off the strip ( 9 );    a folding assembly ( 43 ) for folding the sheet ( 3 ′) about the group (G) of cigarettes to form a wrapped group ( 4 ) of cigarettes; and    a sealing assembly ( 44 ) for sealing superimposed portions (T) of the sheet ( 3 ′) folded about the group (G) of cigarettes;    the device ( 1 ) being characterized in that the conveyor ( 8 ) comprises a suction belt ( 35 ) for feeding the strip ( 9 ) through the application station ( 12 ;  13 ).    
   
   
       41 ) A device for producing a cigarette packet comprising an inner wrapping ( 3 ), in turn comprising a sheet ( 3 ′) of heat-seal material; the device ( 1 ) comprising: 
 a folding assembly ( 43 ) for folding the sheet ( 3 ′) about a group (G) of cigarettes to form the wrapped group ( 4 ) of cigarettes; and    a sealing assembly ( 44 ) for sealing superimposed portions (T) of the sheet ( 3 ′) folded about the group (G) of cigarettes;    the device ( 1 ) being characterized in that the sealing assembly ( 44 ) comprises at least one oscillating electromagnetic field generator ( 47 ); at least one movable member ( 48 ) of nonconducting material; and actuating means ( 49 ) which move the movable member ( 48 ) into contact with said superimposed portions (T) to keep the superimposed portions (T) correctly superimposed; the generator ( 47 ) being substantially fixed.    
   
   
       42 ) A device for producing a cigarette packet ( 2 ) comprising an inner wrapping ( 3 ), in turn comprising a sheet ( 3 ′) of heat-seal material folded about a group (G) of cigarettes; the device ( 1 ) comprising: 
 a conveyor ( 8 ) for feeding a strip ( 9 ) of heat-seal material along a feed path (P) through a slitting station ( 11 ) and an application station ( 12 ;  13 ) to a cutting station ( 10 );    an operating unit ( 15 ) located at the slitting station ( 11 ) to form a slit ( 6 ) in the strip ( 9 );    an application unit ( 16 ;  17 ) located at the application station ( 12 ;  13 ) to apply an adhesive patch ( 7 ) onto the slit ( 6 );    a cutting assembly ( 42 ) located at the cutting station ( 10 ) to cut said sheet ( 3 ′), complete with the slit ( 6 ) and the patch ( 7 ), off the strip ( 9 );    a folding assembly ( 43 ) for folding the sheet ( 3 ′) about the group (G) of cigarettes to form a wrapped group ( 4 ) of cigarettes; and    a sealing assembly ( 44 ) for sealing superimposed portions (T) of the sheet ( 3 ′) folded about the group (G) of cigarettes;    the device ( 1 ) being characterized in that the application unit ( 16 ;  17 ) comprises blow means for blowing the patch ( 7 ) onto the strip ( 9 ) by emitting at least one air jet crosswise to the feed path (P) and to a surface ( 25 ) of the strip ( 9 ).