Driving apparatus for driving operative units of a packaging machine

Abstract

A driving apparatus ( 70 ) for driving an operative unit ( 24 ) of a packaging machine comprises an electric motor ( 71 ) including a rotor ( 72 ). The driving apparatus ( 70 ) also comprises an articulated quadrilateral ( 75 ) interposed between and connecting the rotor ( 72 ) and the operative unit ( 24 ) in order to transform a rotational motion of the rotor ( 72 ) into an alternate motion of the operative unit ( 24 ), thus rendering the driving apparatus ( 70 ) safer and more reliable.

1 . A driving apparatus for driving at least an operative unit of a packaging machine suitable to complete, in particular to transfer, position or fold groups of smoking articles and relative wrap sheets and inner containing elements, or collars, or their parts, in order to package them in packets, comprising electric step motor means and linearization means suitable to convert a rotational motion into a linear motion, acting on said operative unit, characterized in that said electric step motor mean comprises, solid with the drive shaft, a rotor radially carrying an eccentric pin, said eccentric pin acting on said linearization means, wherein the movement of the eccentric pin which acts on the linearization means corresponds to about 180° determined by an alternate to-and-fro rotation of the rotor wherein the rotor is associated to a bearing which absorbs thrusts, said bearing being positioned in a support mean, said support mean being solid with a bearing structure. 
     
     
         2 . (canceled) 
     
     
         3 . (canceled) 
     
     
         4 . The apparatus as in  claim 1 , wherein the support mean supports and positions the electric step motor. 
     
     
         5 . The apparatus as in  claim 1 , wherein said linearization means comprise an articulated quadrilateral. 
     
     
         6 . The apparatus as in  claim 5 , wherein said articulated quadrilateral comprises a connecting rod hinged on said pin. 
     
     
         7 . The apparatus as in  claim 6 , wherein said articulated quadrilateral comprises a rocker arm hinged at a free end of said connecting rod. 
     
     
         8 . The apparatus as in  claim 7 , wherein said articulated rocker arm performs a respective work travel along a further circumference arc (α). 
     
     
         9 . The apparatus as in  claim 5 , and comprising a plurality of levers, or a further articulated quadrilateral, interposed between and connecting said articulated quadrilateral and said operative unit. 
     
     
         10 . The apparatus as in  claim 6 , and comprising a damper acting on said connecting rod to damp oscillations of said connecting rod beyond said work travel. 
     
     
         11 . A packaging machine for forming packets of smoking articles, in particular cigarettes, comprising a driving apparatus as defined in  claim 1 .