Method and unit for forming a tobacco bead

Abstract

A method and unit for forming a tobacco bead, whereby a forming conveyor conveying the tobacco bead cooperates with a pressing device for compacting portions of the tobacco bead equally spaced with a given spacing, and cooperates with a shaving device; and whereby a distance between the pressing device and the forming conveyor is regulated independently of a distance between the shaving device and the forming conveyor, and as a function of a linear travelling speed of the forming conveyor or a physical quantity related to it.

1 ) A method of forming a tobacco bead by means of a forming conveyor ( 3 ) for conveying the tobacco bead ( 2 ); a pressing device ( 11 ) for compacting portions ( 14 ), equally spaced-with a given spacing ( 15 ), of the tobacco bead ( 2 ) conveyed on the forming conveyor ( 3 ); and a shaving device ( 21 ) coordinated with the forming conveyor ( 3 ) and for removing a surplus tobacco portion ( 22 ) off the tobacco bead ( 2 ); the method providing for regulating a first distance (D2) between said shaving device ( 21 ) and said forming conveyor ( 3 ) as a function of the characteristics of the tobacco bead ( 2 ); and the method being characterized by estimating a linear travelling speed (VL) of the forming conveyor ( 3 ), and regulating a second distance (D1) between said pressing device ( 11 ) and said forming conveyor ( 3 ) as a function of said linear travelling speed (VL) of the forming conveyor ( 3 ).  
     
     
         2 ) A method as claimed in  claim 1 , and further reducing said second distance (D1) alongside an increase in said linear travelling speed (VL) of the forming conveyor ( 3 ).  
     
     
         3 ) A method as claimed in  claim 1 , and further regulating said second distance (D1) substantially independently of said first distance (D2).  
     
     
         4 ) A method as claimed in  claim 3 , and further regulating said first distance (D2) by means of a first actuator ( 36 ), and regulating said second distance (D1) by means of a second actuator ( 19 ) independent of said first actuator ( 36 ).  
     
     
         5 ) A method as claimed in  claim 1 , and further estimating the linear travelling speed (VL) of said forming conveyor ( 3 ) by direct measurement of the linear travelling speed (VL).  
     
     
         6 ) A method as claimed in  claim 1 , and further estimating the linear travelling speed (VL) of said forming conveyor ( 3 ) by measuring a physical quantity related to the linear travelling speed (VL).  
     
     
         7 ) A method as claimed in  claim 6 , and further estimating the linear travelling speed (VL) of said forming conveyor ( 3 ) by means of a measurement of said tobacco bead ( 2 ).  
     
     
         8 ) A method as claimed in  claim 7 , and further estimating the linear travelling speed (VL) of said forming conveyor ( 3 ) by measuring a height (H) of said tobacco bead ( 2 ).  
     
     
         9 ) A method of forming a tobacco bead by means of a forming conveyor ( 3 ) for conveying the tobacco bead ( 2 ); a pressing device ( 11 ) for compacting portions ( 14 ) of the tobacco bead ( 2 ) equally spaced with a given spacing ( 15 ); and a shaving device ( 21 ) coordinated with said forming conveyor ( 3 ) and for removing a surplus tobacco portion ( 22 ) off the tobacco bead ( 2 ); the method providing for regulating a first distance (D2) between the shaving device ( 21 ) and the forming conveyor ( 3 ) as a function of the characteristics of the tobacco bead ( 2 ); and the method being characterized by regulating a second distance (D1) between the pressing device ( 11 ) and the forming conveyor ( 3 ), and regulating the second distance (D1) independently of the first distance (D2).  
     
     
         10 ) A method as claimed in  claim 9 , and further regulating said first distance (D2) by means of a first actuator ( 36 ), and regulating said second distance (D1) by means of a second actuator ( 19 ) independent of said first actuator ( 36 ).  
     
     
         11 ) A method as claimed in  claim 9 , and further estimating a linear travelling speed (VL) of the forming conveyor ( 3 ), and regulating a second distance (D1) between said pressing device ( 11 ) and said forming conveyor ( 3 ) as a function of said linear travelling speed (VL) of the forming conveyor ( 3 ).  
     
     
         12 ) A method as claimed in  claim 11 , and further reducing said second distance (D1) alongside an increase in said linear travelling speed (VL) of the forming conveyor ( 3 ).  
     
     
         13 ) A method as claimed in  claim 11 , and further estimating the linear travelling speed (VL) of said forming conveyor ( 3 ) by direct measurement of the linear travelling speed (VL).  
     
     
         14 ) A method as claimed in  claim 11 , and further estimating the linear travelling speed (VL) of said forming conveyor ( 3 ) by measuring a physical quantity related to the linear travelling speed (VL).  
     
     
         15 ) A method as claimed in  claim 14 , and further estimating the linear travelling speed (VL) of said forming conveyor ( 3 ) by means of a measurement of said tobacco bead ( 2 ).  
     
     
         16 ) A method as claimed in  claim 15 , and further estimating the linear travelling speed (VL) of said forming conveyor ( 3 ) by measuring a height (H) of said tobacco bead ( 2 ).  
     
     
         17 ) A method as claimed in  claim 15 , and further estimating the linear travelling speed (VL) of said forming conveyor ( 3 ) by measuring the density of said tobacco bead ( 2 ).  
     
     
         18 ) A method as claimed in  claim 15 , and further estimating the linear travelling speed (VL) of said forming conveyor ( 3 ) by measuring the mass of tobacco per unit of length of said tobacco bead ( 2 ).  
     
     
         19 ) A method as claimed in  claim 9 , and further measuring the density of said tobacco bead ( 2 ), and regulating said second distance (D1) as a function of said density of the tobacco bead ( 2 ).  
     
     
         20 ) A method as claimed in  claim 19 , and further increasing said second distance (D1) alongside an increase in said density of the tobacco bead ( 2 ).  
     
     
         21 ) A method as claimed in  claim 9 , and further measuring, downstream from said shaving device ( 21 ), a mass of tobacco per unit of length of said tobacco bead ( 2 ), and regulating said second distance (D1) as a function of said mass of tobacco per unit of length of the tobacco bead ( 2 ).  
     
     
         22 ) A method as claimed in  claim 21 , and further increasing said second distance (D1) alongside an increase in said mass of tobacco per unit of length of the tobacco bead ( 2 ).  
     
     
         23 ) A method as claimed in  claim 9 , and further measuring a height (H) of said tobacco bead ( 2 ), and regulating said second distance (D1) as a function of said height (H) of the tobacco bead ( 2 ).  
     
     
         24 ) A method as claimed in  claim 23 , and further increasing said second distance (D1) alongside a reduction in said height (H) of the tobacco bead ( 2 ).  
     
     
         25 ) A unit for forming a tobacco bead, the unit ( 1 ) comprising a forming conveyor ( 3 ) for conveying the tobacco bead ( 2 ) at a given linear speed (VL); a pressing device ( 11 ) for compacting portions ( 14 ), equally spaced with a given spacing ( 15 ), of the tobacco bead ( 2 ); a shaving device ( 21 ) coordinated with said forming conveyor ( 3 ) and for removing a surplus tobacco portion ( 22 ) off the tobacco bead ( 2 ); and first regulating means ( 36 ) for regulating a first distance (D2) between the shaving device ( 21 ) and the forming conveyor ( 3 ) as a function of the characteristics of the tobacco bead ( 2 ); and the unit ( 1 ) being characterized by comprising second regulating means ( 19 ) for regulating a second distance (D1) between the pressing device ( 11 ) and the forming conveyor ( 3 ) substantially independently with respect to said first regulating means ( 36 ).  
     
     
         26 ) A unit as claimed in  claim 25 , wherein said first regulating means ( 36 ) comprise a first actuator ( 36 ), and said second regulating means ( 19 ) comprise a second actuator ( 19 ) independent of the first actuator ( 36 ).  
     
     
         27 ) A unit as claimed in  claim 25 , and further comprising estimating means ( 38 ) for estimating a linear travelling speed (VL) of the forming conveyor ( 3 ); said second regulating means ( 19 ) regulating said second distance (D1) as a function of said linear travelling speed (VL) of the forming conveyor ( 3 ).  
     
     
         28 ) A unit as claimed in  claim 27 , and further comprising sensor means ( 41 ) for measuring said linear travelling speed (VL) of the forming conveyor ( 3 ); said estimating means ( 38 ) being connected to the sensor means ( 41 ) to estimate the linear travelling speed (VL) of said forming conveyor ( 3 ) by direct measurement of the linear travelling speed (VL).  
     
     
         29 ) A unit as claimed in  claim 27 , and further comprising further sensor means ( 40 ;  42 ) for measuring a physical quantity related to said linear travelling speed (VL) of the forming conveyor ( 3 ); said estimating means ( 38 ) being connected to the further sensor means ( 40 ;  42 ) to estimate the linear travelling speed (VL) of said forming conveyor ( 3 ) by means of the measurement of said physical quantity related to the linear travelling speed (VL).  
     
     
         30 ) A unit as claimed in  claim 29 , wherein said further sensor means ( 40 ;  42 ) effect a measurement of said tobacco bead ( 2 ).  
     
     
         31 ) A unit as claimed in  claim 30 , wherein said further sensor means ( 42 ) measure a vertical height (H) of said tobacco bead ( 2 ).  
     
     
         32 ) A unit for forming a tobacco bead, the unit ( 1 ) comprising a forming conveyor ( 3 ) for conveying a tobacco bead ( 2 ); and a shaving device ( 21 ) coordinated with said forming conveyor ( 3 ) to remove a surplus tobacco portion ( 22 ) off the tobacco bead ( 2 ), and comprising two mutually cooperating, rotary shaving disks ( 23 ); the unit ( 1 ) being characterized in that the shaving device ( 21 ) comprises a frame supporting two independent electric motors ( 32 ), each of which comprises a respective shaft ( 29 ) supporting and operating a respective said shaving disk ( 23 ); and a control unit ( 38 ) for activating the two said electric motors ( 32 ) to impart a respective given angular speed to each said shaving disk ( 23 ).  
     
     
         33 ) A unit as claimed in  claim 32 , wherein control unit ( 38 ) activates the two said electric motors ( 32 ) to impart the same angular speed to said shaving disks ( 23 ).  
     
     
         34 ) A unit as claimed in  claim 32 , wherein said control unit ( 38 ) activates the two said electric motors ( 32 ) to impart two different angular speeds to said shaving disks ( 23 ).  
     
     
         35 ) A unit as claimed in  claim 32 , and further comprising first sensor means for determining the density of the tobacco in said tobacco bead ( 2 ); said control unit ( 38 ) activating the two said electric motors ( 32 ) to impart to each said shaving disk ( 23 ) a respective given angular speed which is a function of said density of the tobacco.  
     
     
         36 ) A unit as claimed in  claim 32 , and further comprising second sensor means ( 41 ) for determining the linear travelling speed (VL) of said forming conveyor ( 3 ); said control unit ( 38 ) activating the two said electric motors ( 32 ) to impart to each said shaving disk ( 23 ) a respective given angular speed which is a function of said linear travelling speed (VL).  
     
     
         37 ) A unit as claimed in  claim 32 , and further comprising third sensor means ( 40 ) for determining the mass of tobacco per unit of length of said tobacco bead ( 2 ); said control unit ( 38 ) activating the two said electric motors ( 32 ) to impart to each said shaving disk ( 23 ) a respective given angular speed which is a function of said mass of tobacco per unit of length of said tobacco bead ( 2 ).  
     
     
         38 ) A unit as claimed in  claim 32 , and further comprising a pressing device ( 11 ) for compacting portions ( 14 ) of the tobacco bead ( 2 ) equally spaced with a given spacing ( 15 ); said pressing device ( 11 ) comprising a lobed wheel ( 11 ), and a further electric motor ( 17 ) for rotating the lobed wheel ( 11 ) at a given angular speed (VA).