Collection unit spare wheels

Collection unit spare wheels, comprising a gear assembly (50) which allows transmission of a torque, the gear assembly (50) comprising a cam (10) having a movement of wobble when transmitting the set gear (50) the torque, and at least one stop (1) which limits the travel of said cam (10) in the movement of wobble, where the unit (100) comprises at least one guide surface (110 ) interacting with a contact surface (2) of the stop (1) and determines the path of said stop (1) when the cam (10) acts on the stop (1), acting as the stop (1) on the cam ( 10) from an edge (12) of said cam (10).