Assembly for loading and unloading products, comprising a balanced loading and unloading arm installed at a first location and having a compass-style duct system mounted by one of its ends on a base and provided at the other of its ends with a connection system suitable for connecting the compass-style duct system to a coupling means installed at the second location, this assembly comprising, in addition, a cable joined on the one hand to means integral with the base and suitable for subjecting this cable to a constant tension and suitable for being joined, on the other hand, to the second location, the assembly also comprising guiding means capable of co-operating with the cable so as to guide the connection system along a trajectory materialized by the said cable until the connection system is brought into a position of connection to the coupling means.