Method and apparatus for producing wrappings for smoking articles

Abstract

In a method of producing wrappings for smoking articles, the wrappings advance intermittently along a forming path with several stations, including a sealing station sealing the wrapping. Each wrapping continuously alternates a period of stop in a station with a period of movement between stations. A first predetermined stop time is associated with a first station, and a second predetermined stop time, greater than the first stop time, is associated with a second station, which is a sealing station. The second station has multiple positions for operating simultaneously on wrappings lots. Between stops in the first station, wrappings advance with a single step, with displacement that brings a wrapping to replace the immediately preceding wrapping. Between stops in the second station, wrappings advance with a multiple step, with a displacement that brings a wrappings lot to replace the immediately preceding lot in the positions of the second station.

1 . Method for producing wrappings for smoking articles and the like, comprising advancing the wrappings intermittently along a forming path which includes a plurality of stations, of which at least one station is a sealing station for performing a sealing operation on the wrapping, so that each wrapping continuously alternates a period of stop in a station with a period of movement between one station and a next station, said method wherein:
 a first predetermined stop time is associated with at least a first station of said stations and a second predetermined stop time, greater than said first predetermined stop time, is associated with at least one second station of said stations, which is a sealing station,   said second station has a plurality of positions for operating simultaneously on a lot of the wrappings ,   between one stop and the other in said first station the wrappings advance with a single step, with a displacement that brings a wrapping to replace an immediately adjacent wrapping in the first station, and   between one stop and the next stop in said second station, the wrappings advance with a multiple step, with a displacement that brings a whole lot of the wrappings to replace an immediately adjacent lot of the wrappings in multiple positions of the second station.   
     
     
         2 . Method according to  claim 1 , wherein:
 along the forming path, at least a first lot of the wrappings is transported by a first conveyor device and at least a second lot of the wrappings is transported by a second conveyor device separated from the first conveyor device,   each conveyor device is controlled with different stop times and displacements depending on whether the lots of the wrappings transported by the conveyor device are located at said first station or at said second station,   when a lot transported by the first conveyor device is located at said first station, in the second station a lot is transported by the second conveyor device.   
     
     
         3 . Method according to  claim 2 , wherein said separate conveyor devices are belt conveyors. 
     
     
         4 . Method according to  claim 2 , wherein said separate conveyor devices are wheel conveyors. 
     
     
         5 . Method according to  claim 1 , wherein all the wrappings are transported along the forming path by a same belt conveyor device, and wherein the support structure of the entire belt conveyor device is translatable intermittently with respect to a stationary structure between two extreme operating positions, along a direction parallel to a longitudinal direction of the belt conveyor device, and wherein:
 the first station is located along a first branch of said belt conveyor device, and the second station is located along a second branch of the belt conveyor device.   the belt of the belt conveyor device moves intermittently with a single step, with a movement that brings to the first station a wrapping immediately following the wrapping which was located before in the first station;   movement of the support structure of the belt conveyor device takes place from a first end position to a second end position in an intermittent manner, with steps synchronous to the steps of the belt and of a length equal to length of each step of the belt with respect to the support structure of the belt conveyor device, so that while a plurality of wrappings advance through the first station, the same lot of wrappings remains in the second station,   the movement of the support structure of the belt conveyor device from the second end position to the first end position takes place with a single movement having a length as to cause a replacement of the entire lot of wrappings that was before in the second station with a new lot of wrappings.   
     
     
         6 . Method according to  claim 1 , wherein said second station with multiple positions has a periodic operating step in which it is translated along said forming path so as to accompany a lot of said wrappings with equal speed of displacement in their movement along the forming path, whereby the stop of said lot of wrappings relative to said second station has a longer duration than the stop of each wrapping in the first station. 
     
     
         7 . Apparatus for producing wrappings for smoking articles and the like, comprising a conveyor device for intermittently advancing the wrappings along a forming path which includes a plurality of stations, of which at least one station is a sealing station, for performing a sealing operation on the wrapping, in such a way that each wrapping continuously alternates a period of stop in a station with a period of movement between one station and the other, said apparatus wherein:
 said conveyor device is configured and controlled in such a way that a first predetermined stop time is associated with at least a first station of said stations and a second predetermined stop time, greater than said first predetermined stop time, is associated with at least one second station of said stations, which is a sealing station,   said second station has multiple positions for operating simultaneously on a lot of wrappings,   between one stop and the other in said first station the conveyor device is configured and controlled to advance the wrappings with a single step, that is, with a displacement that brings a wrapping to replace the immediately adjacent wrapping in the first station, and   between one stop and the other in said second station, the conveyor device is configured and controlled to advance the wrappings with a multiple step, that is, with a displacement that brings a whole lot of wrappings to replace an immediately adjacent lot in the multiple positions of the second station.   
     
     
         8 . Apparatus according to  claim 7 , wherein:
 the conveyor system comprises a first conveyor device for transporting at least a first lot of wrappings along the forming path, and a second conveyor device, separated from the first conveyor device, for transporting at least one second lot of wrappings along the forming path,   each of the two conveyor devices is associated with a control device programmed for controlling the respective conveyor device with different stop times and displacements depending on whether the lots of wrappings transported are located at said first station or at said second station,   the two conveyor devices are configured so that when a lot of wrappings transported by the first conveyor device is located at said first station, in the second station a lot of wrappings is transported by the second conveyor device.   
     
     
         9 . Apparatus according to  claim 8 , wherein said separate conveyor devices are belt conveyors. 
     
     
         10 . Apparatus according to  claim 8 , wherein said separate conveyor devices are wheel conveyors. 
     
     
         11 . Apparatus according to  claim 7 , wherein all the wrappings are transported along the forming path by a same belt conveyor device, and wherein the support structure of the entire belt conveyor device is translatable intermittently with respect to a stationary structure between two extreme operating positions, along a direction parallel to the longitudinal direction of the belt conveyor device. 
     
     
         12 . Apparatus according to  claim 7 , wherein said second station with multiple positions is translatable along the forming path to accompany a lot of said wrappings with equal speed of displacement in movement along the forming path, whereby the stop of said lot of wrappings relative to said second station has a longer duration than the stop of each wrapping in the first station. 
     
     
         13 . Apparatus according to  claim 7 , wherein all the wrappings are transported along the forming path by the same conveyor device comprising a linear electric motor, with a stator defining a ring, or an elongated ring, on which a series of equipment move independently. 
     
     
         14 . Apparatus according to  claim 7 , wherein:
 the apparatus comprises a plurality of drawer supports each of the supports receiving and support a respective wrapping containing a respective group of smoking articles during transport along said forming path and through said stations,   each drawer support comprises at least one first wall and at least one second wall parallel to each other and spaced apart, to define a space therebetween for containing the respective group of smoking articles,   said first wall and said second wall have side portions in relief for the lateral containment of the respective group of smoking articles within said containment space,   said walls are configured and arranged so that the containment space defined therebetween is open on two opposite sides and on a third front side, so that said drawer support does not interfere with sealing operations carried out on edges of the respective wrapping which protrude from said sides of the containment space.   
     
     
         15 . Apparatus according to  claim 14 , wherein said first wall is divided into two wall portions separated by a slit which extends over an entire length of the wall.