Device and procedure for the batch transfer of tobacco products

Abstract

Cigarettes are transferred in batches adopting a procedure that includes the steps of feeding loose cigarettes en masse into a hopper with a back wall and two side walls delimiting a top inlet and a bottom outlet, also a shutter by which the bottom outlet is opened or closed, and actively varying the geometry of the side walls so that the internal volume of the hopper is adapted to accommodate the quantity of cigarettes admitted through the inlet, by means of an actuator mechanism connected to the side walls. Thus, it becomes possible to monitor and control both the rate at which the cigarettes flow into the hopper, and the pressure to which the single cigarettes are subjected while occupying the hopper and during the process of filling a tray.

1 . A device for the batch transfer of tobacco products, comprising: 
 a hopper furnished with a back wall and two side walls combining to delimit a top inlet opening through which tobacco products are admitted, and a bottom opening from which the tobacco products are discharged;    a shutter by which the bottom opening is opened or closed;    a motion-inducing mechanism connected to the side walls, such as will actively vary the geometry of the side walls so as to adapt the internal volume of the hopper to the quantity of tobacco products admitted through the top opening.    
   
   
       2 . A device as in  claim 1 , wherein the motion-inducing mechanism comprises at least one sensor able to monitor a parameter indicating the quantity of tobacco products admitted to the hopper, an actuator connected to the side walls, and a control unit connected to the at least one sensor and to the actuator in such a way that it can receive a signal from the sensor representative of the parameter indicating the quantity of tobacco products admitted to the hopper and generate a signal by which the actuator is piloted to vary the geometry of the side walls.  
   
   
       3 . A device as in  claim 2 , further comprising a support element carrying a container to be filled with tobacco products, and a motor by which the support element is set in motion vertically between a first position of proximity to the bottom opening of the hopper and a second position distanced from the selfsame bottom opening, in such a way that the container can be filled during the movement of the support element from the first position toward the second position.  
   
   
       4 . A device as in  claim 3 , wherein the motor is connected to the control unit in such a way that the rate of descent of the support element can be varied in response to the signal received from the sensor representative of the parameter indicating the quantity of tobacco products admitted to the hopper.  
   
   
       5 . A device as in  claim 4 , wherein each of the side walls of the hopper comprises a flexible leaf.  
   
   
       6 . A device as in  claim 5 , wherein each of the side walls comprises a terminal portion associated pivotably with a fixed frame near the top inlet opening, and the leaf presents a first end inserted slidably in the terminal portion and a second end associated pivotably with the fixed frame near the bottom discharge opening.  
   
   
       7 . A device as in  claim 6 , wherein the actuator comprises a pair of levers, each presenting a first end hinged to the fixed frame and a second end linked to one respective side wall, and at least one motor by which each lever is caused to rotate about the relative first end.  
   
   
       8 . A device as in  claim 7 , wherein the at least one motor of the actuator comprises a double acting pneumatic or fluid power cylinder.  
   
   
       9 . A device as in  claim 1 , further comprising a conveyor extending along a predetermined direction between a first unit and a second unit by which the tobacco products are processed, and presenting an intermediate opening positioned facing the top inlet opening of the hopper, by way of which the tobacco products are caused to drop into the hopper.  
   
   
       10 . A device as in  claim 9 , wherein the at least one sensor is located near the conveyor at a point along the predetermined direction.  
   
   
       11 . A device as in  claim 10 , wherein the at least one sensor is located above the inlet opening of the hopper.  
   
   
       12 . A device as in  claim 10 , wherein the at least one sensor comprises a feeler able to sense the depth of the flow of tobacco products advancing on the conveyor in the predetermined direction.  
   
   
       13 . A procedure for the batch transfer of tobacco products, comprising the steps of: 
 feeding a flow of tobacco products into a hopper furnished with a back wall and two side walls combining to delimit a top inlet opening, and a bottom opening from which the tobacco products are discharged, also a shutter by which the bottom opening is opened or closed;    actively varying the geometry of the side walls and the internal volume of the hopper, according to the quantity of tobacco products admitted to the hopper, by means of a motion-inducing mechanism linked to the side walls.    
   
   
       14 . A procedure as in  claim 13 , further comprising the steps of positioning a container in alignment with the bottom discharge opening of the hopper, operating the shutter to open the bottom opening, lowering the container to allow the passage of the tobacco products from the hopper into the container and controlling the rate of descent of the container on the basis of a parameter indicating the quantity of tobacco products entering the hopper.  
   
   
       15 . A procedure as in  claim 14 , wherein the step of feeding a flow of tobacco products into the hopper includes the step of directing the products along a predetermined direction on a conveyor that extends between a first unit and a second unit by which the tobacco products are processed, and presents an intermediate opening positioned facing the top inlet opening of the hopper, by way of which the tobacco products are caused to drop into the hopper.  
   
   
       16 . A procedure as in  claim 15 , wherein the parameter indicating the quantity of tobacco products admitted to the hopper is given by the rate of flow of the tobacco products advancing on the conveyor.  
   
   
       17 . A procedure as in  claim 16 , wherein the step of actively varying the geometry of the side walls includes the steps of deforming the side walls according to a prescribed law of deformation corresponding to a reference flow rate of the tobacco products advancing on the conveyor, sensing the effective flow rate of the tobacco products advancing on the conveyor, comparing the effective flow rate with the reference flow rate, and varying the law of deformation in the event that the effective rate differs from the reference rate.  
   
   
       18 . A procedure as in  claim 17 , wherein the step of controlling the rate of descent of the container includes the steps of lowering the container according to a prescribed law of motion corresponding to a reference flow rate of the tobacco products advancing on the conveyor, sensing the effective flow rate of the tobacco products advancing on the conveyor, comparing the effective flow rate with the reference flow rate, and varying the law of motion in the event that the effective rate differs from the reference rate.  
   
   
       19 . A device as in  claim 1 , wherein each of the side walls of the hopper comprises a flexible leaf.  
   
   
       20 . A device as in  claim 5 , wherein the actuator comprises a pair of levers, each presenting a first end hinged to the fixed frame and a second end linked to one respective side wall, and at least one motor by which each lever is caused to rotate about the relative first end.