Drum conveyor and method to rotate rod-shaped articles

Abstract

The invention relates to a drum conveyor defining a drum rotational axis and an outer peripheral surface, the drum conveyor comprising: o a first seat and a second seat, each of the first seat and second seat being adapted to transport a rod-shaped article, the first seat and the second seat being located at the outer peripheral surface of the drum conveyor; o a first shaft and a second shaft, wherein the first shaft defines a first shaft longitudinal axis and the second shaft defines a second shaft longitudinal axis, the first shaft longitudinal axis and the second shaft longitudinal axis being substantially perpendicular to the drum rotational axis, the first seat being attached to the first shaft and the second seat being attached to the second shaft, so that a rotation of the first shaft around the first shaft longitudinal axis and of the second shaft around the second shaft longitudinal axis cause the first seat and the second seat to rotate; o a pusher coupled with the first shaft and the second shaft by mechanical coupling, the pusher being adapted to linearly move along a pusher direction and engage with the first shaft and second shaft while moving; o an actuator adapted to move the pusher along the pusher direction while the drum conveyor rotates around the drum rotational axis so as to rotate the first shaft and the second shaft and the attached first seat and second seat at the same time. The invention also relates to a method to rotate rod-shaped articles.

1 . A drum conveyor defining a drum rotational axis and an outer peripheral surface, the drum conveyor comprising:
 a first seat and a second seat, each of the first seat and second seat being adapted to transport a rod-shaped article, the first seat and the second seat being located at the outer peripheral surface of the drum conveyor;   a first shaft and a second shaft, wherein the first shaft defines a first shaft longitudinal axis and the second shaft defines a second shaft longitudinal axis, the first shaft longitudinal axis and the second shaft longitudinal axis being substantially perpendicular to the drum rotational axis, the first seat being attached to the first shaft and the second seat being attached to the second shaft, so that a rotation of the first shaft around the first shaft longitudinal axis and a rotation of the second shaft around the second shaft longitudinal axis cause the first seat and the second seat to rotate;   a pusher coupled with the first shaft and the second shaft by mechanical coupling, the pusher being adapted to linearly move along a pusher direction and engage with the first shaft and second shaft while moving;   an actuator adapted to move the pusher along the pusher direction while the drum conveyor rotates around the drum rotational axis so as to rotate the first shaft and the second shaft and the attached first seat and second seat at the same time.   
     
     
         2 . The drum conveyor according to  claim 1 , wherein the actuator comprises a cam, the cam pushing the pusher along the pusher direction while the drum conveyor rotates around the drum rotational axis. 
     
     
         3 . The drum conveyor according to  claim 2 , wherein the drum conveyor comprises a first wall and a second wall, located at two opposite sides of the outer peripheral surface, and wherein the cam is defined by a portion of the first wall. 
     
     
         4 . The drum conveyor according to  claim 3 , wherein the first wall is stationary. 
     
     
         5 . The drum conveyor according to  claim 1 , wherein the pusher comprises a first end and a second end, and the first end of pusher is adapted to engage with the actuator. 
     
     
         6 . The drum conveyor according to  claim 1 , wherein the pusher is provided with an elastic element. 
     
     
         7 . The drum conveyor according to  claim 5 , wherein the actuator comprises a cam, the cam pushing the pusher along the pusher direction while the drum conveyor rotates around the drum rotational axis, and 
       wherein the elastic element is adapted to bias the pusher towards the cam for maintaining a contact between the pusher and the cam. 
     
     
         8 . The drum conveyor according to  claim 1 , wherein the pusher is telescopic and comprises an inner tubular element and an outer tubular element, the inner tubular element being slidable in the outer tubular element along the pusher direction. 
     
     
         9 . The drum conveyor according to  claim 1 , wherein the mechanical coupling between the first shaft and second shaft and the pusher comprises a rack and a pinion. 
     
     
         10 . The drum conveyor according to  claim 9 , wherein the pusher comprises a first rack and a second rack, and the first shaft comprises a first pinion and the second shaft comprises a second pinion; the pusher being positioned so that the first rack engages with the first pinion and the second rack engages with the second pinion. 
     
     
         11 . The drum conveyor according to  claim 1 , wherein the linear movement of the pusher defines an amplitude and wherein the amplitude is so selected that the first seat and the second seat rotate at least of 90 degrees. 
     
     
         12 . The drum conveyor according to  claim 1 , comprising a plurality of N seats and a plurality of N shafts, and N/2 pushers, wherein each k-th, where k=1 . . . N/2, pusher of the N/2 pusher is coupled to two nearest neighbour shafts (i, i+1), where i=1, 3, 5 . . . N−1 according to one or more of the preceding claims. 
     
     
         13 . A system for turning rod-shaped articles, the system comprising:
 a drum conveyor according to  claim 1 ;   an inspection apparatus adapted to inspect rod-shaped articles positioned on the first seat or on the second seat.   
     
     
         14 . A method to rotate rod-shaped articles having a longitudinal axis, the method comprising:
 providing a drum conveyor defining a drum rotational axis and an outer peripheral surface, the drum conveyor comprising:
 a first seat and a second seat located at the outer peripheral surface of the drum conveyor; 
 a first shaft and a second shaft, wherein the first shaft defines a first shaft longitudinal axis and the second shaft defines a second shaft longitudinal axis, the first shaft longitudinal axis and the second shaft longitudinal axis being substantially perpendicular to the drum rotational axis, the first seat being attached to the first shaft and the second seat being attached to the second shaft; 
 a pusher forming a mechanical coupling with the first shaft and the second shaft; 
   positioning a rod-shaped article in the first seat and in the second seat;   rotating the drum conveyor around the drum conveyor rotational axis;   moving the pusher linearly along a pusher direction while rotating the drum conveyor;   transforming the linear movement of the pusher into a rotational movement of the first shaft and of the second shaft around the first shaft longitudinal axis and the second shaft longitudinal axis so as to rotate the longitudinal axes of the rod-shaped articles in the first seat and second seat.   
     
     
         15 . The method according to  claim 14 , wherein the step of rotating the drum conveyor comprises:
 rotating the drum conveyor around the drum rotational axis by 360 degrees; and wherein, in the same 360 degrees rotation of the drum conveyor, the step of rotating the first shaft and the second shaft comprises:   rotating the first shaft and the second shaft from a configuration where the longitudinal axes of the rod-shaped articles in the first seat and in the second seat are perpendicular to the drum rotational axis to a configuration where the longitudinal axes of the rod-shaped articles in the first seat and in the second seat are parallel to the drum rotational axis;   rotating the first shaft and the second shaft from the configuration where the longitudinal axes of the rod-shaped articles in the first seat and in the second seat are parallel to the drum rotational axis back to the configuration where the longitudinal axes of the rod-shaped articles in the first seat and in the second seat are parallel to the drum rotational axis.