A motive device (4) for shaking rods (31), comprising a support body (43), an arm (41) pivoted on the support body (43) around a pivot axis (410) and intended for bearing a plurality of shaking rods (31), a first motive or motor apparatus (45, 48) including a cam wheel (48) contacting the arm (41), and a second motive or motor apparatus (55). The arm (41) extends in a substantially radial direction relative to the pivot axis (410) and is rotatable in a reciprocating motion between a first angular position and a second angular position relative to the support body (43). The first motor apparatus (45, 48) is configured for implementing a first angular motion of the arm (41) towards the first angular position through a rotation of the cam wheel (48) the second motor apparatus (55) is configured for implementing a second angular motion of the arm (41) towards the second angular position, said second angular motion being in a sense opposite to the first angular motion.
